An Overview of Unigraphics

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-An Overview of UnigraphicsThe User Interface and the Sketcher

In this lesson, you will: Learn about the Unigraphics NX user interface. Open a part file. Examine a sketch and make changes to it.

Keep in mind that this course is a very small sample of the functionality of Unigraphics NX. For in-depth treatment of specific functional areas, please see the corresponding CAST courses. NOTE: Most of the illustrations in this course show the Windows user interface. In most respects, the Unix interface is very similar. Where there are significant differences, they are described.

Opening a Part File Start Unigraphics NX. The method you use to start Unigraphics NX will depend on your particular installation and platform. If you do not know how to do this, see your system administrator. Notice that the Unigraphics NX window shows you a "tip" when there are no open part files. You can use the Next Tip button if you want to see more.

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Opening a Part File Open the part file There are two ways to open a part file in Unigraphics NX: Using the menu bar OR Using the Open icon

Either choose the Open icon

in the toolbar...

...OR choose File from the menu bar (#1 below), then choose Open from the pull-down menu (#2). (For the rest of the course, this type of action will be referred to as File Open.)

3 When you are told to "choose" an option, this means move the cursor over it and click the left mouse button (also referred to as mouse button #1 or MB1).

Opening a Part File Opening the Part File (Windows) If you are working on a Unix system, skip this page — go on to the next page. The Open Part File dialog is displayed — the name of the dialog is displayed in the title bar at the top. The "Look in" field tells you which drive or folder is currently selected. In the example below, the current folder is "NX".

Find the ug_overview directory and double-click on it.

...which opens that folder and places its name in the "Look in" field.

Notice that, when a part file is selected, as it is above, a preview picture of it is displayed in the dialog.

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Notice also that you will see this icon file.

any time you see the name of a Unigraphics NX part

Double-click on the ugovrvu_sketch.prt part file.

The part file is opened.

Opening a Part File Opening a Part File (Unix) If you are working on a Windows system, skip this page — go on to the next page. The name of the dialog is displayed in the title bar at the top.

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The Filter field controls what is displayed in the Directories and Files list boxes. In this example, the Filter field is set to /tmp/parts...

The Directories list box shows the subdirectories included in /tmp/parts. The Files list box shows the files contained in /tmp/parts which match the ".prt" extension in the Filter field. In the Filter field, key in the name of the desired directory (the place where your part files are stored), then press Enter. Notice that the File Name field at the bottom of the dialog also shows the name of the current directory.

Select ugovrvu_sketch.prt.

Notice that the name of the part you selected is now also displayed in the File Name field, added onto the end of the directory path.

Choose OK at the bottom of the dialog.

6 The part file is opened.

The User Interface On Windows, notice that the part file name is now displayed in the title bar of the Unigraphics NX window, and that the system automatically appended the file extension .prt to the name you entered.

On Unix, the part file name is displayed at the top of the graphics window.

This illustration will give you a brief overview of some of the main areas of the Unigraphics NX user interface. They are described in more detail on the following pages.

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Notice that several toolbars are displayed when you first start Unigraphics NX. NOTE: The illustrations and instructions in this course assume that you are starting Unigraphics NX for the first time. If you have used Unigraphics NX before, the window sizes, toolbars, etc. may look different, since their status is saved when you exit.

The User Interface User Interface Components The Unigraphics NX interface contains a number of different elements — The menu bar...

Toolbars...

The resource bar (on Windows only)...

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The graphics area...

And the Cue line, which prompts you with instructions about what to do next.

The User Interface Toolbars Toolbars are displayed in different areas of the interface, both horizontally and vertically. They contain "icons" which activate different Unigraphics NX functions. The Utility toolbar is docked just above the Cue line. The work layer number is displayed in the Utility toolbar. This is the layer where newly-created geometry is placed.

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The User Interface More About Toolbars and Icons You can display the names of all the available toolbars. Put the cursor over any toolbar (or blank area next to a toolbar) and right-click (i.e., press mouse button #3, sometimes referred to as MB3, the button on the right). A pop-up menu appears, showing the names of all available toolbars, with check marks next to the ones that are currently displayed.

To turn a toolbar on or off, you can select its name from this pop-up menu. This same function is available using the Toolbars option on the View pull-down menu. Click anywhere away from this menu, to dismiss it. You can see the names of the icons (these are called "tooltips") by holding the cursor over them. Hold the cursor over any icon for a few seconds. The name is displayed.

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The User Interface The Work Coordinate System The Work Coordinate System (WCS) is displayed in the graphics window.

Location values that you key in are usually entered relative to the WCS (although you can also use the absolute coordinate system). You can move and reorient the WCS, and the system sometimes does this for you automatically, such as when you are creating a sketch or a feature.

Entering the Modeling Application

Unigraphics NX contains a number of different applications, which are environments for particular kinds of activities. For the next section, you will use the Modeling application. Choose Application from the menu bar. A pull-down menu displays most of the major functional areas of Unigraphics NX. Notice the key sequences to the right of the menu options. You can use these "shortcuts" to activate that function. For example, Ctrl+M will start the Modeling application. Choose Modeling from the pull-down menu.

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A new set of toolbars are displayed which are specific to the Modeling application.

Sketches A sketch is a drawing of geometry that will be used in some way to create a body. Usually, sketches are created without too much concern for exact size and shape, then they have constraints added (both dimensional and geometric) to determine their exact final shape.

In this section, you will learn how to make changes to a sketch. Later, you will create a solid body using the sketch and other features.

Sketches Activating the Sketch Choose Edit

Sketch from the menu bar.

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The sketch is displayed. The dimensions show the size that has been established for the elements in the sketch.

Notice that the dimension on several elements has been established by a word, rather than a number. These are called "expressions". You can also see that three different elements in the sketch are all defined by the same expression — "Thickness".

Sketches Changing a Dimension You can change the sketch by directly editing one of its dimensions.

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Choose the Dimensions icon

in the toolbar.

The Dimensions dialog is displayed. You can see that it lists all the parameters that you see in the graphics area. Select the p1=7.939 parameter in the list box in the dialog. The parameter and its value are now displayed in the text boxes below.

Key in 8.500 for a new value for p1. When you press Enter, watch the graphics area. The size of the line immediately changes. OK the dialog (either choose OK or press MB2, the middle mouse button). You can also change a size by directly selecting it in the graphics area. Double-click on the p2=18.000 dimension in the graphics area. A "dynamic input box" is displayed, showing the parameter name and its current value.

Notice that, all the time, the Cue line is prompting you with what you should do next. It's telling you to enter a new value for this dimension.

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Key in 20 for the new value, and press Enter. The size of the dimension is immediately changed.

Choose the Finish Sketch icon

to exit from Sketch edit mode.

Sketches Changing an Expression There's one more way you can change the size of a dimension—by changing the expression that defines it. Each time an object is created in Unigraphics NX, expressions (i.e., equations) are created by the system, describing information about the object's size, location, and other information. This is true in the Sketcher and in other operations, such as creating features. You can also create expressions yourself, and then use the names of the expressions in place of actual values as you create geometry. Later, you can change the values of the expressions and the part will automatically update. Choose Tools

Expression from the menu bar.

The Expressions dialog is displayed, showing all the expressions currently defined in the part and their values. Select the Thickness=3.090 expression.

In the text field, change the value to 5, then press Enter.

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The new value is displayed in the list box.

OK the dialog. Look at the graphics area—you can see that the sketch is "thicker" in all three places where the "Thickness" expression defined the size.

Geometric Constraints Besides the dimensional constraints you have already seen, a sketch is defined by its "geometric" constraints. These include characteristics of the geometry; for example: A line is vertical, horizontal, or parallel to another line. Two or more radii are the same size. A line and a circle are tangent. Two circles are concentric. There are many other geometric characteristics that can determine the shape of a sketch. You will not create any geometric constraints in this exercise, but you can examine this sketch to see what constraints already exist. Choose Edit

Sketch once again to display the sketch and its dimensions.

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Choose the Show All Constraints icon. The arrows that you see represent geometric constraints that define the lines as horizontal or vertical.

Choose the Show All Constraints icon

again to turn the arrows off.

Geometric Constraints Displaying and Removing Geometric Constraints There are several ways you can display the geometric constraints — you have already seen one method, where you display all the geometric constraints at once. You can also display the constraints associated with individual objects.

Choose the Show/Remove Constraints icon. The Show/Remove Constraints dialog is displayed. Notice that the Selected Object option is active.

17 Move the cursor over various lines and arcs. Constraint markers are displayed as elements are highlighted. The small circles stand for "tangent", the arrows for "horizontal" and "vertical". Click on All in Active Sketch to turn the option on.

All the constraints in the active sketch are listed in the dialog.

Select LINE4 Horizontal in the list box. The corresponding geometry is highlighted in the graphics area, and the geometry name shown in the list is also displayed.

Once you have highlighted a constraint, you can remove it Choose Remove Highlighted in the dialog, then OK the dialog. The constraint has been removed. You can prove this by changing the line so it is NOT horizontal. Put the cursor over the point on the upper right, hold down MB1, and drag the cursor.

18 Release the mouse button, leaving the line at an angle.

The line can be dragged to be at an angle, because the horizontal constraint has been removed. Notice, however, that the vertical lines did NOT change—they are still constrained and must remain vertical.

Choose the Finish Sketch icon Choose File

Close

to exit from Sketch edit mode.

All Parts.

OK the Question dialog when it asks "are you sure". You will now go on to learn about how to create a feature from a sketch.

Creating and Editing Features

In this lesson, you will: Create a solid body by extruding a sketch. Learn how to change layers. Add a feature to the model and position it correctly. Learn different ways to visualize the part. Open the ugovrvu_extrude.prt part file.

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Notice that this is the same sketch that you saw in the previous part. Start the Modeling application by pressing Ctrl+M or choosing Application

Modeling.

Changing the Work Layer One way to keep your model organized is to keep different types of geometry on different layers. Unigraphics NX lets you put objects on up to 256 separate layers, which can be displayed or not, as you choose. Newly created geometry is assigned to the work layer, which is displayed in the Utilities toolbar. You will change the work layer so that the solid body you are going to create will go on a different layer than the sketch. Key in 2 in the Work Layer box, then press Enter.

You can also use the Layer Settings dialog to control the display of the layers. You can access this dialog using the Layer Settings icon (which is right next to the work layer) or by choosing Format Layer Settings from the menu bar.

Creating a Solid Body

You will now create a solid body by extruding the sketch in a specified direction, then you will add other features to it.

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Choose the Extruded Body icon the menu bar.

or choose Insert

Form Feature

Extrude from

As the Cue line tells you, the first thing you must do is identify the string of curves that will be extruded. Select any curve in the sketch. The entire sketch is selected when you select a curve. OK the dialog to indicate that you are done selecting curves for the string. If you get a message warning you that the "read only" part has been modified and you will not be able to save it, just OK the warning dialog. The Extruded Body dialog is displayed, showing you the different ways you can specify the extent of the feature. Choose Direction_Distance.

Creating a Solid Body Specifying the Direction and Length of the Extrusion The next steps are to define the direction and length of the extrusion. The default direction is along the ZC axis, as shown by the arrow that is displayed. You could use the Vector Constructor dialog options to identify a different vector if needed. OK the Vector Constructor dialog. Key in an End Distance value of 12, then OK the dialog. The solid body is created.

Cancel the dialog.

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Creating a Solid Body Orienting the Model Unigraphics NX contains a number of options that help you visualize the part in space. You can turn the model around...

Use the Rotate icon

to turn the part.

You can move the model...

Use the Pan icon

to move the model around the graphics area.

And you can set the rotation to a predefined view. Choose the Isometric icon from the view menu.

The model is displayed in an isometric view.

Creating a Solid Body Changing the Model's Appearance You can also change the appearance of the model in a number of ways.

22 Choose the Gray Thin Hidden Edges icon (use the small black triangle to bring up the menu of hidden edge choices).

The hidden edges are "obscured", to further aid visualization. (You can also display them as dashed lines, or remove them completely.)

Choose the Shaded icon. Now the part is fully shaded and its shape is even more clearly visible.

Choose the Wireframe icon

to remove the shading.

Changing Layer Settings

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Now that you have created the solid body, you no longer need to have the sketch displayed. By changing layer settings, you can remove the sketch from the display.

Choose the Layer Settings icon bar.

or choose Format

Layer Settings from the menu

The Layer Settings dialog is displayed. Notice that the status of layer 1 is "Selectable".

There are four different settings a layer can have: Work - The work layer. There will always be one and only one work layer. Almost all

new objects you create go on this layer. Objects on this layer are visible and you can select them. Selectable - Objects on a selectable layer are visible and you can select them. Visible Only - Objects on this type of layer are visible, but you cannot select them. Invisible - You cannot see objects on an invisible layer, and you cannot select them. Remember, the sketch is on layer 1 and the solid body is on layer 2. Double-click on layer 1. (You could also select layer 1, then choose Invisible.) The layer status becomes "blank", meaning it now has "invisible" status.

OK the dialog. The sketch is no longer displayed. Close the part file without saving it.

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Adding Features to a Part

To create a completely defined part, you continue to add features to it. This section will show you how to add a form feature to a part. Open part file 10112734.001.prt from the ug_overview subdirectory.

Start the Modeling application. The area of the part shown below was constructed using an extruded body similar to the one you just created.

The extruded body was combined with other features to create the final shape. You will now add one more feature, to create a hole through the center of the large cylinder.

Adding Features to a Part Adding a Hole Feature You will turn off the shading, so that you can see the edges of the part better.

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Choose the Wireframe icon. Now the part should look like this.

If the hidden edges are not gray, choose the Gray Thin Hidden Edges icon.

Adding Features to a Part Starting the Feature Choose the Hole icon. At the top of the dialog, there are three icons, which you can use to create three different kinds of holes—Simple, Counterbore, and Countersink.

Notice that the Placement Face icon, in the Selection Steps section, is active - it looks "pushed in".

Also, the Cue line is asking you to select the "planar placement face."

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This is the face that the hole will start on. However, you should set the values of the parameters first. Enter 10 in the Diameter field. This hole is going to go all the way through the part, so the depth and tip angle are not important. Now you are ready to select the placement face.

Adding Features to a Part Selecting the Faces You must select two faces for a thru hole: The face the hole feature is to be placed on (the placement face), and The face the hole is to go through (the thru face). You will select the top face of the cylindrical portion of the part for the placement face. Hold the cursor over the center of the large cylinder. The cursor changes into a cross with 3 small dots.

This is called the QuickPick cursor—it lets you know that there is more than one object at that location that could be selected. Click MB1.

27 The upper face of the cylinder is highlighted, and the QuickPick dialog appears. Notice that, when the cursor is over the number "1", the upper face is highlighted and the type of geometry is displayed below the dialog.

Move the cursor over the number 2. Now the lower face is highlighted.

In this way, you can see the object that is going to be selected, before you do the actual selection. Move the cursor back over the number 1, then click MB1 to select the top face. An image of the hole is displayed where you selected.

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Adding Features to a Part Selecting the Thru Face Now that the placement face has been specified, the Thru Face icon is automatically active in the Selection Steps area.

Also, the Cue tells you to select the "thru" face.

What if you did not want to create a thru hole, i.e., if you wanted it to be a specific depth? The Status area is telling you that the "thru face" selection is an optional step.

If you did not want this to be a thru hole, you would use MB2 to progress to the next step without selecting a face. Hold the cursor over the top of the part and click MB1 again. Since the top face has already been selected, it automatically selects the bottom face. Notice that now the Depth and Tip Angle options are grayed out—they are not needed for a thru hole. OK the dialog to accept the settings.

Adding Features to a Part Positioning the Hole The Positioning dialog is displayed, to let you position the feature exactly where you want it. As you can see, there are many ways you can position a feature.

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Choose the Point onto Point icon. Notice that the Status area tells you that the position of the feature is "underspecified." It will continue to display this message until the feature is fully positioned.

The Cue asks you to select the target object. This means an object (usually an edge) on the existing part that you will position the feature to. Select the edge of the upper circular face.

As you can see in the dialog, you can specify that the point you want is the center of this arc, or an end or tangent point. The Arc Center option is selected by default. OK the dialog to accept the Arc Center option. The hole feature is moved into position, and its volume is subtracted from the part.

Choose the Shaded icon. There are many other types of features you can add to parts — pockets, slots, and grooves, primitive features like blocks and cylinders, etc.

Adding Features to a Part End of Lesson Close all part files.

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Working with Assemblies

In this lesson, you will: Examine an assembly. Learn how to use the Assembly Navigator. Blank and unblank assembly components. Working with an Assembly

A Unigraphics NX assembly part file is a collection of components (which are other Unigraphics NX part files), which are located relative to each other using various methods. Open part file throttle.assm.001.prt. (This part is located in the throttle_assm subdirectory, in the ug_overview directory.)

You can see that the part you were just working on is one of the components of the assembly.

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The Assembly Navigator The Assembly Navigator lets you see a graphical display of the "tree structure" of your assembly. It is accessed differently on Windows and Unix. Display the Assembly Navigator. On Unix, choose the Assembly Navigator icon. On Windows, right-click on the Assembly Navigator tab in the resource bar and choose Undock. If necessary, move the Navigator window so it is not obscuring the graphics window or the training material. You must undock the Assembly Navigator on Windows for all CAST courses, if you are displaying CAST in the resource bar—otherwise the Navigator would replace the CAST content! However, under normal circumstances you do not need to undock it—you can display it right in the resource bar. The Assembly Navigator is displayed. (The remaining illustrations will show the Assembly Navigator on Windows. The functionality is identical on Unix.) Each line in the Assembly Navigator window represents one component, or a subassembly, in the assembly. A plus sign ("+") represents a subassembly that is not expanded.

Select the plus sign next to 10136940.assm.001. The plus sign changes to a minus sign, and the components of the subassembly are now listed under its name.

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Select the minus sign to collapse the subassembly.

The Assembly Navigator Blanking and Unblanking Components You can also use the Assembly Navigator to turn the display of assembly components on and off. Select the red check mark next to the 10123741.part.001 part, at the bottom of the Assembly Navigator window.

The red check mark is changed to gray, and the large throttle body part is removed from the display.

Move the cursor over the 10123741.part.001 name in the Assembly Navigator.

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The name of the part is displayed, and so is a box representing the size of the part that you cannot see.

Select the gray check mark. It turns red, and the throttle body is displayed again.

The Assembly Navigator The Assembly Navigator Pop-Up Menu There is a pop-up menu available in the Assembly Navigator that gives you a shortcut to many of the most commonly used functions. In the Assembly Navigator, put the cursor over the throttle body part and right-click. The pop-up menu appears.

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You can see that there are quite a number of items on this menu, allowing you to execute many different commands on the parts displayed in the Assembly Navigator. Choose Blank from the pop-up menu. This has exactly the same effect as selecting the red check mark — the check mark next to the part is changed to gray and the part is removed from the display. Put the cursor over the throttle body part in the Navigator window, then right-click and choose Unblank from the pop-up menu. The part is returned to its original condition. Do not close the part file—go on to the next section.

Working with Drawings In this lesson, you will: Get a brief overview of the Drafting application. Create auxiliary views. Add dimensions to a view.

Creating a Drawing

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In the Drafting application, you can create a drawing, then add dimensions, notes, symbols, etc. to complete a 2D layout of your part. Choose Application

Drafting.

This model already contains one drawing, which is named SH1. Notice also that several new toolbars are displayed, and the Modeling application toolbars have been removed.

You will create a new drawing. Choose Drawing

New.

There is also a New Drawing icon that is available for the Drawing Layout toolbar. As always, you can add and remove icons from your toolbars at any time. The New Drawing dialog is displayed, with options that let you specify the size, name, and units of the drawing. Notice that the default name for the new drawing is SH2, but you could change it. Change the drawing to C size.

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OK the dialog.

Creating a Drawing Adding a View to a Drawing Choose the Add View to Drawing icon

or choose Drawing

Add View.

The Add View dialog is displayed, with the Import View icon selected. This lets you import any of the views from the Modeling application onto your drawing.

Notice also that the TOP view is selected in the list box. This is the view that will be created.

Move the cursor around in the graphics area. You can see a white rectangle where your cursor is. This represents the size of the geometry in the view that will be created.

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Put the cursor in the center of the graphics area and click MB1. The TOP view is created. The status of colors, layers, etc. is determined by preferences that have been set.

Creating a Drawing Creating Orthographic Views Choose the Orthographic View icon

in the dialog.

First you must specify the "parent view", i.e., the view that the orthographic view is projected from. Select the TOP view name in the dialog, or select inside the view in the graphics area. Move the cursor around in the graphics area. As you can see, the view that will be created depends on the location of your cursor. Move the cursor to the right of the Top view and click MB1. The orthographic view is created.

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You can create many other kinds of views - auxiliary views, detail views, and several different types of section views. Cancel the Add View dialog.

Creating a Drawing Adding Dimensions to a Drawing Choose the Zoom icon on the Standard toolbar. Click and drag a rectangle to expand your view of the lower left corner of the Top view.

Click on the small triangle next to the Inferred Dimension icon icon on the menu.

then choose the Hole

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The Hole dialog is displayed. Select the hole on the lower left.

A "ghost" image of the dimension appears. Drag the dimension into place and click MB1 to define its location.

You can continue to add many different kinds of dimensions, notes, and symbols to your drawing, to create a complete blueprint.

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Creating a Drawing Closing the Part Files When you are finished, choose File Close All Parts (if you want to continue to work with Unigraphics NX) or File Exit (to completely exit from Unigraphics NX). It is not necessary to save any of your part files. This has been a very brief, high-level overview of some of the major functions in Unigraphics NX. Please see the CAST Online Library for a more complete description of the many additional capabilities of Unigraphics NX.

-Unigraphics-NX EssentialGetting Started in Unigraphics The Unigraphics NX Essentials course is an overview of the common Unigraphics NX functions that are used in every application. Audience This course is intended for all beginning users of Unigraphics NX. It can also be useful as a reference for those familiar with previous versions of Unigraphics NX. Prerequisites There are no prerequisites for this course. Course Content Getting Started in Unigraphics NX — Starting a Unigraphics NX session, using the mouse,

opening part files, creating new part files, and closing part files. Controlling the Display of Toolbars — How to display (and hide) toolbars and icons on

toolbars. Working With Dialogs — Looking at the various types of options on typical Unigraphics NX

dialogs.

41 Selecting Objects — Different methods of selecting Unigraphics NX objects in the graphics

window. Using zoom, rotate, and pan. Using the resource bar to look at the names of features displayed on the Model Navigator. Manipulating the WCS — Ways to move, rotate and orient the work coordinate system (the

WCS). Organizing Parts — How to use layers to show objects or make them invisible. Displaying Parts — Methods you can use to display the part in various different ways. Using Online Documentation — A look at the different ways to find and display

documentation about specific subjects. Using Common Tools — Using the Class Selection, Point Constructor and Vector

Constructor dialogs. Part Files A number of part files have been supplied with this tutorial. The part files associated with this class are stored in the uge subdirectory and their names also start with uge. You will not be asked to save your parts as you work through this course. Of course, if you wish to, you can. Just be sure you have write access to the directory where you want to keep your personal part files.

Getting Started in Unigraphics NX

This first lesson will get you started with all of the basic file manipulation procedures, window manipulation procedures.

In this lesson, you will learn how to: open, close, save, and reopen Unigraphics NX part files and how to create new part files. recognize the purpose of each object that makes up the Unigraphics NX window. create new part files. end a Unigraphics NX session.

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Working With Part Files In this part of the lesson you will learn: the nomenclature of the mouse. details about opening a part file. how a part is displayed in the graphics window.

Working With Part Files Starting Unigraphics NX There are three different ways you can access the CAST (Computer Assisted Self Teach) online courses: You can use the CAST option to start Unigraphics NX Or you can start Unigraphics NX, then choose CAST from the Help pull-down menu. Or you can point your web browser to the appropriate location.

Unigraphics NX functions are divided into applications of common capabilities: Gateway lets you open part files and do some basic manipulations. Modeling lets you create solid models. Drafting lets you create drawings of solids. Assemblies lets you assemble individual solid models into a large representation. Manufacturing lets you create the programs for NC machines to cut out solids. and so on.

Working With Part Files Buttons on the Mouse These are the names for the mouse buttons that will be used in CAST courses.

43 MB1 = Left button MB2 = Center button MB3 = Right button

There are several different mouse button actions that you will use throughout these lessons: To click, select, or choose means to place the mouse cursor where you want it in the graphics window, then to press and immediately release MB1. To double-click means to press MB1 quickly two times in succession. To click and drag means to press MB1 and hold it down while you move the cursor. If you are using a two-button mouse, you will need to press the left and right buttons together to create the action of the center mouse button on a three-button mouse.

Working With Part Files Opening a Part File Right now the title bar tells you that there is no part open. Right below the names of options on the main menu are just two icons: The icon that looks like a piece of paper is called New and is used to create new part files. The icon that looks like a folder being opened is used to open existing part files.

In the menu bar, place the mouse cursor on the File option, then click MB1 (the left mouse button) one time to display the File menu.

The File menu will give you all the actions that you can use for working with files.

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On the File menu, choose (click on) the Open option. The Open Part File dialog is displayed.

Working With Part Files Choosing the Directory You Need The following instructions will show you how to choose the directory on Windows. If you are on a Unix system, you will see a few differences. Windows uses the standard Windows dialog.

The Look In field displays the name of the directory you are currently in. Below that the list box displays all of the files (folders) that are in that directory. On Unix you won't see folders, just the names of directories.

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Working With Part Files Finding the Parts You Will Need For This Lesson (Using Windows) The subdirectory you need is in the CAST part files directory. If the "parts" directory is not displayed in the Look In field, choose the arrow on the right end of that field to display all of the directories available, then choose the parts directory.

Double-click on the uge directory (folder).

All of the part files in this directory are now displayed in the list box. NOTE to Unix users: To display a directory above or below the currently listed directory, you will need to: double-click the name with the two dots to move UP to the previous directory. double-click the directory name with the one dot to display the parts in that directory.

Working With Part Files The Read-Only Warning Dialog When you open a part that is "read-only" protected, the system will give you a warning dialog that gives you the full name of the part, then lists all the warnings that were issued while loading. The "Read Only" part means you can work on it, but you can not save any of your changes while you are working in the CAST directory.

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If you wanted, you could save this part in a directory where you had write privileges. However, for most of the CAST lessons, you will not need to save a part file. Whenever you get this warning, just choose the OK button on the dialog. The warning will disappear and you can continue.

Working With Part Files Using the Preview Window to Choose the Part File You Want to Open

NOTE to Unix users: You won't see the preview option in Unix. You want to open the part file called uge_intro.prt. Be sure there is a check mark in the box next to the word Preview. (If there isn't, place the cursor in the box, then click MB1 once in the box to turn it on.)

Remember, just OK the Open Warning dialog whenever it appears. Choose uge_intro.prt (place the cursor over this name, then click MB1 so that the name highlights).

The image of the part appears in the preview window so that you can be sure it's the part you want to open.

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Choose OK (at the bottom right corner of the dialog). As your part file is being loaded into working memory, you will see the "Work in Progress" dialog. This dialog appears when an active function is working so that you could stop it if you needed to.

NOTE to Unix users: Instead of the Work In Progress dialog, you'll see a red light while the system is working, and a green light when it has finished.

Working With Part Files The Performance Meter On Windows machines, you will see a little "meter" at the bottom right hand corner of the window called the "performance meter". When the system is working, you'll see a series of little blue moving squares.

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If the system takes longer than a few seconds, you'll see a time displayed in the Status line.

Working With Part Files The Appearance of the Part in the Graphics Window When the part is finished loading, the Work in Progress dialog disappears and the part appears in the graphics window.

In this case, the part was saved with the solid shading. So it displays with that shading when you open it. Leave the part file open as you continue on to the next section in this lesson.

The Unigraphics NX User Interface The Unigraphics NX window uses standard Windows file selection dialogs, toolbars, and so on.

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On Unix the Unigraphics NX window looks slightly different. In this part of the lesson you will learn: about the different parts of the Unigraphics NX window how to change the size of the Unigraphics NX window. about the purpose of the Cue line and Status line.

The Unigraphics NX User Interface The Nomenclature of the Unigraphics NX User Interface You are still working with part file uge_intro.prt. The overall window is called the "Unigraphics NX window" or the "main window" or sometimes the "background window". Included within this overall window are the title bars, the main menu, toolbars, dialogs (as you call them up) and the graphics window.

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NOTE to Unix users: The arrangement of icons on the left side of the graphics window is a little different.

The Unigraphics NX User Interface The Window Title Bar and Menu Bar The title bar of the main Unigraphics NX window shows you the release of Unigraphics NX you are working on and the name of the active application. Right under the title bar are the options on the "main menu" (also called the "action bar").

You've already used the File menu to open the part file.

The Unigraphics NX User Interface Graphics Window The part itself is displayed in the graphics window.

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In later lessons you will work extensively with the various elements of this window.

The Unigraphics NX User Interface Changing the Size of the Graphics Window in Unix and Windows The first time you run Unigraphics NX, the graphics window is, by default, maximized. Choose the Restore Down button to display the graphics window as a separate window.

The icon changes to Maximize so that you return the graphics window to its original size.

You can also grab an edge or corner of the window and drag it to a different size.

You can also move any window by placing the cursor in the title bar of the window, pressing (and holding) MB1, then moving the mouse to drag the window to a different location.

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Unix users can enlarge the graphics window by selecting one of the edges and stretching it larger.

The Unigraphics NX User Interface Graphics Window Title Bar The name of the file you have opened appears in two places in the title bar of the graphics area.

The words "Read Only" tell you that this part can not be saved with its current name. If you did make any changes to this part, you would need to rename it before you could save it. (You'll see how to do this toward the end of this lesson.)

The Unigraphics NX User Interface The Dialog Area of the Graphics Window A dialog (or dialog box) is a moveable window that you use to control the way you shape and change a part. In the Unigraphics NX window the dialogs you use will appear to the left of the graphics window.

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Since dialogs are windows, you can move them to other locations if you need to. If you do move a dialog, the system will remember the new location and place all other dialogs that follow in that same location.

The Unigraphics NX User Interface The Cue Line and the Status Line The Cue line and Status line are located at the bottom of the Unigraphics NX window. The Cue line will give you specific information about the steps you may use in a procedure. Here's an example.

Choose the Open icon

(it's near the top left side of the Unigraphics NX window).

The Open Part File dialog appears, and the Cue line gives you a suggestion on what you can do next.

54 Throughout these lessons, you will see how important it is to refer to the cues in order to better understand the steps of the procedures that you will be using. The information in the Status line will confirm the status of many of the actions you will be using during these lessons or give you additional information about the steps you may use in a procedure (such as using optional steps). In this case (preparing to open a part file), it tells you what the system is doing.

Dismiss the Open Part File window by choosing the Cancel button or by choosing the Close icon at the top right corner of the dialog window.

Creating New Part Files Most of the time you will open an existing part file. But sometimes you will need to start from scratch. In this part of the lesson you will: create a new part display information about the new part change from one part to another when you have more than one part open.

Creating New Part Files Creating a New Part Be sure you are in the uge directory (check the Look In field). Choose the New icon

from the Standard toolbar (or you can choose File

The New Part File dialog is displayed.

New).

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Creating New Part Files Choosing the Units for the New Part You need to define the type of units you want this part to be in - English or metric. In this case you want to create a metric part file. Set the units for this part to Millimeters.

NOTE to Unix users: The Units options look different in Unix.

If you wished, you could use this dialog to change the directory where this new file would be placed if you saved it. (You won't be able to save this part in the CAST uge directory.) You are ready to name this new part. Click in the File Name field to focus it. The insert cursor (a vertical line) must be blinking in this field for you to be able to enter text.

You may use up to 256 characters for a part file name (but this includes the total path name). You can use 128 characters for the actual part file name. The valid characters you may use depends on the operating system and the standards at your company. In this next step you will not need to enter the ".prt" extension after you key in the part name. The system will add it for you automatically. In the File Name field, key your last name (you can use lower case letters but NO spaces). Choose OK on the dialog. The new part file is created but not saved.

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Creating New Part Files The Graphics Window of the New Part The name you keyed in now appears in the title bar of the graphics window

There is nothing in the new part file yet, except: a white border around the graphics area the name of the view (TOP WORK) and the image of the work coordinate system (WCS) in the center of the view.

The orientation of the WCS symbol shows that you are looking directly onto the X-Y plane of the part (thus the name of the view).

Creating New Part Files Displaying Information About the New Part File You can display information about any part. For example, you may want to be sure you have really created a file for metric parts. Choose Information

Part

Loaded Parts.

The Information window is displayed.

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It gives you a great deal of information, but how would you know that the part file is metric? Look under the headings "Units" and "Modifiable Piece Part".

There are several ways you can dismiss the Information window: You can choose File Exit on the window itself. Or you can click the Close button on the window. Or you can choose the Information icon on the Standards toolbar (which is not currently displayed). Choose the Close button on the Information window.

Creating New Part Files Opening Another Part File You can open the same part file you used in the previous lesson, this time using the icon.

Choose the Open icon. On the Open Part File dialog, double-click on uge_wcs.prt. The part appears in the graphics window.

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Creating New Part Files Changing the Displayed Part Using the Window Menu You can work on several parts in one Unigraphics NX session by moving from one part to the other. Click on the Window option on the main menu.

The Window pull-down menu displays the names of two parts: uge_intro the part with your name (that you created) Both are "open" parts (that is, "loaded"), but not currently displayed. You can change the displayed part back to the fitting. Choose uge_intro. The menu disappears. The uge_intro part is displayed again (and has become the active work part).

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Creating New Part Files Trying to Open an Already Displayed Part What would happen if you tried to open a part that was already open? Right now part file uge_intro is the active part file.

Choose the Open icon. On the Open Part File dialog, choose (double-click) uge_intro.prt. You get a warning dialog that gives you three choices.

You could use this dialog to change to another part or reopen the same part. In this case you chose a part that was already displayed, so you can either reopen it or just cancel the dialog. Cancel the dialog.

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Closing, Saving and Reopening Part Files When you open an existing part file, you are actually working on a copy of the file. Your changes will not be kept unless you save the part over the original. (If you open a new part file, nothing really exists until you save it for the first time.) In this part of the lesson, you will: save a part file under a different name. reopen previously opened part files. use the resource bar to open recently opened parts. use the File menu to open recently opened parts. close selected part files. close all part files. You will also see how to end a Unigraphics NX session.

Closing, Saving and Reopening Part Files Saving a Part File Whenever you change a part, the word "Modified" will appear in the title bar of the graphics window to indicate that you have made changes to the part but that you have not yet saved it over the original.

Remember, in CAST you are working in a read-only directory, so you won't be able to actually save any parts. But you can see how it works. Choose File

Save.

Because you are working in a read-only protected directory, you get a "Save Failed" warning. The reason is shown at the end: No write access.

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Choose OK on the warning dialog. After a part is saved, the Status line will say "Part file saved", and the word "Modified" will be removed from the graphics area window title bar.

Closing, Saving and Reopening Part Files Saving a Part Under a Different Name As you saw on the File menu, there are several other ways you can save part files. You can save a part file under its existing name. Or you can save the part file under a different name Or you can use save all open part files at one time. Choose File

Save As.

The Save Part File As dialog is displayed.

To save this part under a new name, you would key the name into the File Name field, then choose OK. Cancel the Save Part File As dialog. To save all open (loaded) parts, you would use File

Save All.

Continue on to the next section in this lesson.

Closing, Saving and Reopening Part Files Closing All Part Files When you close a part file, it clears the part file from working memory, but does not save any changes you have made on it.

62 Choose File

Close.

When you choose Close from the File menu, you get another menu (called a "sub-menu" or "cascade" menu). This menu gives you all of the different ways you can close part files.

The top two options on the cascade menu will let you close only those parts you select or close all parts that are loaded. Choose All Parts. You get a question dialog that asks if you are sure you want to close all open (loaded) parts.

OK the Question the dialog. The graphics window now looks like it did when you first began your Unigraphics NX session.

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Closing, Saving and Reopening Part Files Opening Recently Opened Parts Using the Resource Bar

NOTE to Unix users: There is no resource bar for Unix. After you have closed a part, you often need to open it a little later Instead of using the Open icon (or the File Open menu), you can display all the names of parts you have recently worked with, then choose the part you want to open. On the bar on the right side of the Unigraphics NX window, you would choose the History icon

A page, called the history pallet, would be displayed. It would reveal the names of the part files you had opened in today's session (along with a little picture of the part as it had been saved).

You'll notice that the complete path for the part is included under the part name. If you placed the cursor over any image, you would see the complete path name.

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You can change the amount of history you want the system to keep. The default setting is 20 days.

Closing, Saving and Reopening Part Files Methods For Opening a Part File From the Resource Bar To open a part from the resource bar you can double click on the name of the part or its picture (called "part icon"). You can also place the cursor over the name of the file you want, click MB3, the select Open from the little pop-up menu. A third way you can open a part is to place the cursor on the file name (or picture), press and hold MB1, drag the cursor into the area of the graphics window, then release MB1. You can even use this "drag and drop" method on part files displayed in the Internet Explorer window.

Closing, Saving and Reopening Part Files Opening a Part File From the Resource Bar You can try using the resource bar if you'd like. Since you will be leaving the CASTpage for a moment, you will need to remember this sequence of steps: Click on the History icon on the right side of the window. Double-click on any part file name or picture that you see. Click on the Training icon to return to the CAST instructions.

The part you chose is now displayed in the graphics window.

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Closing, Saving and Reopening Part Files Changing the Display of the Resource Bar In order to display only a list of part file names, you would choose the List icon.

Then you would see a list of recently opened parts.

If you wanted to see the history from yesterday, you would open that folder.

To reveal today's files again, you would close yesterday's folder, and reopen today's.

Closing, Saving and Reopening Part Files Opening a Recently Opened Part Using the File Menu There is yet another way to open a recently opened part. You can choose from a list of recently opened parts that the system maintains. By default, the list will display up to eight parts. And the system will maintain this list even after you leave a Unigraphics NX session. Choose File

Recently Opened Parts.

The Recently Opened Parts cascade menu is displayed. It includes the entire path.

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Choose the name of any part that is not already open: uge_intro.prt or uge_wcs.prt. The part appears in the graphics window.

Closing, Saving and Reopening Part Files Closing Selected Part Files Quite often you will want to close specific part files, perhaps those that you have finished working on. But you will want to keep other files loaded. You can see how this works by closing just the part you created earlier. Choose File

Close

Selected Parts.

The Close Part dialog is displayed.

It lists all parts that are open in your current Unigraphics NX session. Notice that there is a button on this dialog that will let you close all parts. Choose the name of the part you created. Choose OK. Check to see if it is really closed by choosing Window in the main menu.

Closing, Saving and Reopening Part Files Saving a Part File As You Close It If you wanted to, you could save the work part as you closed it. To do this you would choose File

Close

Save and Close.

The "Close" cascade menu would then give you several methods that you could use: You can change the name of the file as you close it. Or you can save all open files and close them. Or you can save all open files and end the Unigraphics NX session.

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Closing, Saving and Reopening Part Files Closing All Part Files At One Time When you are finished with a Unigraphics NX session, you can close all part files that are still open. Choose File

Close

All Parts.

Even though you really haven't changed anything on these parts, you get this question.

OK the dialog. The graphics area goes blank. If you opened the Windows menu, you would see that no parts remain loaded.

Closing, Saving and Reopening Part Files Ending a Unigraphics NX Session Although you probably won't want to do it right now, you will eventually need to end your Unigraphics NX session. If you wanted to end your session now, here is what you would do: First, you would close all of your part files (saving or not saving them as required). Then you would choose File Exit. When the warning dialog came up, you would OK it (or Cancel it to stay in the session). Continue on to the next lesson in this course.

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Controlling the Display of Toolbars A "toolbar" contains icons and commands for commonly used tasks.

Unigraphics NX has many toolbars available for the various applications. Since many are application dependent, they will be available when you are running a particular application. In this lesson, you will learn how to: display (and hide) the toolbars you need. customize your toolbars by adding icons and removing them.

The Gateway Toolbars Because they apply to all Unigraphics applications, they are sometimes referred to as the "Gateway toolbars". These include: the Standard toolbar. the View toolbar. the Application toolbar. the Utility toolbar. and the Selection toolbar.

In this section of the lesson you will learn how to: display the name of a toolbar move (undock) a toolbar

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The Gateway Toolbars Docked and Undocked Toolbars A toolbar is "docked" when it appears to be attached to an edge of the Unigraphics NX window.

A toolbar is "undocked" when it appears all by itself anywhere in your screen area. Since it is then a separate little window, its name appears in the title bar.

The Gateway Toolbars Opening the Part File As you saw in the last lesson, when you first open Unigraphics NX, the title bar has no part name and only two icons are displayed on the one toolbar.

Choose the Open icon. On the Open Part File dialog, double-click on uge_intro.prt. OK the warning message. The part is displayed in the graphics window. The title bar of the graphics window reminds you that this is a "read only" part.

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When you open a part file, you automatically enter the Gateway application. You can see the various default toolbars scattered around the Unigraphics window.

It is possible for the systems people to choose which toolbars and which icons will be displayed by default.

The Gateway Toolbars Displaying the Names of Docked Toolbars When a toolbar is undocked, its name appears in the title bar. You can, however, reveal the name of any docked toolbar. (The name will appear in a little box called the "tooltip".) Place the cursor over the "grip handle" (the ridges) at the left end of the toolbar. The name of the tool bar is displayed under the cursor.

The Gateway Toolbars Checking the Names of the Default Gateway Toolbars Use the tooltips to reveal the names of the various default toolbars docked at the top of the window.

Check the name of the toolbar docked along the bottom of the Unigraphics NX window.

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The Gateway Toolbars The Standard Toolbar The default Standard toolbar gives you selected icons for any work you can do in the Gateway application. Just as you displayed the names of the various toolbars, you can use the same technique to display the names of the icons themselves. Run the cursor over the various icons on the Standard toolbar.

These commands also can be found on one of the pull-down menus on the menu bar. You can see that some icons are grayed out (like the Delete icon). This is because you are not allowed to perform these actions in the Gateway application.

The Gateway Toolbars Undocking a Toolbar All of the toolbars you have seen so far are "docked", i.e., they are "attached" to the menu bar. But you can "undock" or "dock" toolbars at any time. To see how this is done, you can undock the Standard toolbar. Place the cursor over the "grip handle" at the left end of the docked Standard toolbar.

Press (and hold) MB1, drag the toolbar to a location just below the other toolbars, then

72 release the mouse button.

You can dock toolbars horizontally at the top or bottom of the Unigraphics NXwindow; or vertically at the left or right. Toolbars can be docked on Unix in the same fashion as on Windows. You don't need to close this part if you are continuing on to the next section. If, however, you aren't going on, go ahead and close it by: Choosing File Close All Parts Choosing OK on the Question dialog.

Customizing Toolbars In this part of the lesson you will learn how to: display or not display toolbars undock and dock toolbars. display only selected icons on a specific toolbar. rearrange the order of docked toolbars.

Customizing Toolbars Displaying a Hidden Toolbar As you work in the different applications, you will often need to display a toolbar that is available but not displayed. For example, you might need to show the Smart Models toolbar.

73 You should still be working in part file uge_intro.prt. Place your cursor anywhere in the toolbar area (the area above the graphics window). Click MB3 on the mouse (and leave the pop-up menu displayed for a while). (You can also use View

Toolbars to display this same menu.)

The pop-up menu displays the names of all the toolbars you can choose. All of the toolbars that are currently displayed have check marks by their names.

Choose Smart Models from the pop-up menu. The Smart Models toolbar is displayed (and it is undocked).

Customizing Toolbars Hiding a Toolbar By Using the Close Button on the Toolbar There are two ways you turn a toolbar off: If it is docked, you should use the MB3 pop-up menu. If it is undocked, you can use either the MB3 pop-up menu or the following procedure.

74 Place the cursor over the Close button (icon) at the top right corner of the Smart Models toolbar, then click MB1.

The toolbar disappears.

Customizing Toolbars Customizing the Icons Displayed on a Toolbar You can choose which icons you want to have displayed on any toolbar. (This is a procedure that you will use many times in CASTlessons.) Use MB3 (with the cursor in the toolbar area) to display the pop-up menu again. Choose Customize (at the bottom of the menu).

The Customize dialog is displayed. (You can also use Tools dialog.)

Customize to display this

There are four tabs at the top, representing different functions you can perform with this dialog. Be sure the Toolbars tab is selected (that is, it should be standing in front of the other tabs).

On the left side of the dialog is a list of all the toolbars that you can show. Just like the pop-up menu, each has a check mark by its name if it is currently displayed.

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If you wanted to display only the default toolbars, you would choose the Reset All option.

Customizing Toolbars Hiding Icons on a Toolbar Choose the Commands tab on the Customize dialog.

The left side of the Commands pane lists the available toolbars (regardless of whether they are currently visible or not). You may have to scroll to see all of the names in the Toolbars list. Right now the Standard toolbar is selected.

To the right is a list of all the possible icons and commands for the selected toolbar. The options that are currently displayed on the toolbar will have a check in the box preceding the command. You won't need to use several icons on this toolbar in these lessons, so you can hide (remove) them. In the list of commands on the right, scroll down then choose Properties to turn this option off. (You can select the check box or the name itself.)

The icon is immediately removed from the toolbar.

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Customizing Toolbars Adding Icons to a Toolbar There are other icons that you will want to have displayed on this toolbar. If you need to, use the Customize dialog and the options in the Commands box to turn on these icons: On Context Help Documentation Adding these icons has probably expanded the dialog in a vertical direction.

NOTE to Unix users: Toolbars on Unix always appear as one line of icons.

Customizing Toolbars Removing Icons From a Toolbar

You can remove icons by turning them off on the Customize toolbar. Remove these icons from the Standard toolbar. Cut Cop y Past e Also, remove the first two separators. Choose Close on the Customize dialog.

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Customizing Toolbars Changing the Length of a Toolbar You can change the size of a toolbar much as you would change the size of a window. Move the cursor over the right edge of the toolbar until it turns into a two-ended arrow.

Press (and hold) MB1, then drag the end of the toolbar to the right until the preview image shows that it has achieved its full length, then release MB1.

Customizing Toolbars Docking a Toolbar Most of the time you will want toolbars to be docked. You can practice this procedure by docking the Standard toolbar in the position you undocked it from. Place you cursor on the Standard title bar.

Press (and hold) MB1, drag the preview outline of the toolbar up into the docking area under the menu, then release MB1 when the outline looks correct.

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The toolbar is locked in place (and the other toolbars in this line are pushed to the right to make room).

Sometimes you may want the toolbar near the docking area but not want it to dock. To prevent a toolbar from docking, you can press the Control key and MB1 while you are dragging the toolbar.

Customizing Toolbars Rearranging the Order of Docked Toolbars You can also change the order of the toolbars. To do this you would select the grip handle of one of the docked toolbars, press MB1 and drag the toolbar over to another location in the docking area, then release MB1 If you drag a toolbar (horizontally) over or in front of one of the other docked toolbars, the toolbar you are dragging will be docked to the left of the already docked toolbar. To dock to the right, drag a toolbar to the right of an existing docked toolbar. This is true both horizontally and vertically. If you would like the toolbar to be docked horizontally below all the others, drag it to the very bottom left of the docking area. When this docks, it will usually increase the size of the docking area. You'll get the feel of these motions as you practice more with moving and customizing toolbars.

Customizing Toolbars Other Customize Options Use MB3 to display the Customize dialog.

79 Choose the Options tab.

You can use the options on this pane to: Make icons smaller and larger. Picture icons in color or shades of gray. On Windows (but not on Unix), at the bottom of the dialog you will see two options that will let you: Display the Cue and Status lines at the top or bottom of the screen. Change the toolbar docking priority between horizontal and vertical.

When Docking Priority is set to Horizontal, any horizontal toolbars will span all the way to the left and right edges of the main windows, in which case they may cover up vertical toolbars. When Docking Priority is set to Vertical, the horizontal toolbars and docked windows will not cover up anything docked vertically. Close the Customize dialog.

Customizing Toolbars Looking at the Application Menu Click on the Application option in the main menu (and leave it up for a moment). You can see the number of different applications that are available.

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Check out which applications have an icon available for them. (These icons are all on the Applications toolbar.) When you have finished, just place the cursor anywhere away from the menu then click MB1 to dismiss the drop-down menu.

Customizing Toolbars Descriptions of Some Unigraphics NX Applications Gateway (the application you are working in right now) lets you open existing part files, create new part files, save part files, plot drawings and screen layouts, import and export various types of files, and other general functions. It also provides consolidated view display operations, screen layout and layer functions, WCS manipulation, object information and analysis, and access to online help. Gateway is the prerequisite for all other interactive applications, and is the first application you enter when you open Unigraphics. Modeling lets you create solids. To do this you can use 2D and 3D wireframe models, swept and revolved bodies, Boolean operations, and basic associative editing. Feature-based modeling application supports the creation and associative edit of standard design features such as holes, slots, and pockets. It allows you to hollow out solid models and create thin walled objects. A feature can be located relative to any other feature or object and can be instanced to establish associative sets of features. Shape Studio is a separately licensed Unigraphics application that provides additional modeling and analysis tools tailored to aid the conceptual designer. This includes basic options for the initial concept stages, such as the creation and visualization of proposed designs, and progressing through to the production of primary and secondary surfaces.

81 Drafting lets you create engineering drawings from either 3D models created in a modeling application, or 2D designs created from curves. Drafting supports automatic creation of drawing layouts, including orthographic view projection, sectioning, auxiliary and detail views, and isometric drafting. View-dependent and automatic hidden line editing are also supported. Manufacturing lets you take solids you have modeled and create the NC machine cutting paths that would be required to manufacture the part. Assemblies lets you pull together all the parts that would be required for a complete assembly (such as the motor for an automobile). This application supports both "top-down" and "bottom-up" assembly modeling. It supports the "design in context" approach in which changes can be made to the design model of any component while working in the context of the assembly. Knowledge Fusion lets you create/edit/view knowledge fusion objects or adopt Unigraphics NX objects into Knowledge Fusion interactively through a series of dialogs. It's not on this menu, but the Spreadsheet program provides an intelligent interface between the Xess (Unix spreadsheet application) or Excel (Windows spreadsheet application) and Unigraphics.

Customizing Toolbars Displaying the Application Toolbar You won't need to use the Applications toolbar too often in this course, but it would be a good idea to see what is available on it. Use MB3

Customize to display the Customize dialog.

Be sure the Toolbars pane is displayed.

If you need to, display the Application toolbar.

Choose the Commands tab. Choose the Application option in the Toolbars list box.

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Display only these icons on the toolbar (and remove all the separators): Modeling Shape Studio Drafting Assemblies Knowledge Fusion Gateway Close the Customize dialog when you have finished. You can close the part, then go on to the next lesson in this course. Choose File

Close

All Parts.

Choose OK on the Question dialog.

Working With Dialogs A dialog is a collection of buttons, icons, and/or text fields and other options arranged within a window. In this lesson you will practice using these different types of options that will be found on dialogs.

In this lesson, you will learn about: dialogs; what they are for and how to use them. the ways you can display parts in the graphics window.

83 the ways you can control color. using layouts that include more than one view of the part.

Options on Dialogs It will be very important to know how to use the various types of options that are present on Unigraphics NXdialogs.

In this part of the lesson you will discover the purpose and use of: check boxes radio buttons navigation buttons scales and sliders default action buttons.

Options on Dialogs Opening the Part File Open

part file uge_dialogs.prt from the uge subdirectory.

This is a model of a simple rocker device.

Options on Dialogs Opening the Part File

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Open

part file uge_dialogs.prt from the uge subdirectory.

This is a model of a simple rocker device.

Options on Dialogs Check Boxes Choose the Names/Borders tab at the top of the dialog.

This pane has options that let you set your preferences for the display of object names, character size, view names, and view borders. On the Unix platform, you will see some slight differences in the way some of the options are displayed. Check boxes are options that can only be "on" or "off". They are independent of any other option. Right now the two check boxes on this pane are turned on.

85 Click on the check box (or the text itself) to turn the Show View Borders option off

Options on Dialogs Radio Buttons Sometimes options on dialogs look like buttons, sometimes not. However they appear, the word "option" will often be used to describe them. Radio buttons always come in a group of two or more. (Their name comes from the radios found in 1950s cars.) When you choose one option, it is turned on and all other options in the group are automatically turned off. Depending on your system, they may be round or diamond-shaped. In the Object Name Display area of the dialog, choose the Work View option.

The Work View option is selected (turned on) while the other two options are turned off.

Options on Dialogs Navigation Buttons These are standard action buttons that appear at the bottom of most dialogs.

Here are the exact actions each of these buttons perform: The OK button lets you accept all the settings on the dialog and dismiss the dialog. The Apply button lets you accept any changes that you've made on the dialog, but keep the dialog up, available for other changes.

86 The Cancel button lets you cancel any changes you've made on the dialog and dismiss it. (This is especially handy when you discover that you've made mistakes!) When you are opening a series of dialogs, you often get the Back button among the navigation buttons.

This option lets you cancel whatever changes you've made and return to the previous dialog.

Options on Dialogs Scales and Sliders Many times when you can apply a range of values, the dialog will give you a "scale" or "slider" to use rather than a text box. Choose the Screen tab to display the Screen pane.

This pane lets you choose the apparent size that the part will be displayed at within the borders of the graphics window. The range of values is shown beneath the slider. In this case the range goes from 50 percent to 100 percent. You change the fit percentage by moving the slider knob back and forth. The current value is shown just above the slider knob.

Choose the Fit icon

from the View toolbar.

The system fits the image of the part into the area of the graphics window so that it fills it to 100%. Put your cursor on the little slider knob, press and hold MB1, then move the cursor (the slider) to the left until you see a value of 60 or so. Then, release the mouse button.

87 Choose the Apply option at the bottom of the dialog to apply this change but keep the dialog up. You've reset the fit percentage, but nothing changes yet in the graphics window.

Choose the Fit icon

again.

Now the image of the part changes to match the new fit percentage instruction.

Options on Dialogs Moving the Slider By Increments You can also move sliders by set increments by clicking on either side of the slider knob. Place the cursor to the right of the slider knob and press MB1 several times to the value changes to 80 or so. (Your actual increment values will probably be slightly different.)

On some dialogs you will be able to define the increment value you want to use.

Options on Dialogs Default Action Buttons Default action buttons are buttons that you can "press" by using the middle mouse button (the OK mouse button). On Windows these action buttons will have a blue border around them. On Unix they will have a green rectangle around them. For example, the OK button at the bottom of the dialog is the current default action button.

Press MB2 to OK the dialog. The dialog disappears.

88 This button also established the two changes that you made on the dialog: The border around the graphics window is not displayed (but the name of the view is still displayed). The fit percentage is now set to 80% (or so).

Choose the Fit icon. The image gets a little larger.

Options on Dialogs Displaying the Visualization Toolbar There is a Visualization toolbar that you might find useful. Place the cursor in any toolbar area. Click MB3, then choose Visualization from the popup menu. The default icons are displayed on the toolbar. There are quite a few that you won't need to use in these lessons. Place the cursor in a toolbar area again. Click MB3, then choose Customize from the popup menu. Be sure the Commands pane is displayed. In the Toolbars list box, choose Visualization. There are many icons available for this toolbar, but you'll only need a few of them for this introductory course. The names of all the icons that can be placed on this toolbar are displayed in the Commands list box. Remove all icons from the toolbar (by turning options off), except for these three. (Scroll the list box as you need to). 1. Visualization Preferences 2. Use System Render Color Palette 3. Use System Wireframe Color Palette

89 You can dock this toolbar or leave it undocked. Choose the Visualization Preferences icon. The Visualization Preferences dialog is displayed. And the Screen pane is displayed because it was the pane that was up when you last OKed this dialog.

Options on Dialogs Drop-Down Menus Choose the Visual tab.

As you can see on this pane, some options include an arrow. The arrow lets you display the "drop-down menu" (sometimes called a "combo box") so you can select one of several possible options.

All the options you can use for a specific option will be displayed in the drop-down menu (and the current option will be highlighted). Click on the arrow in the option opposite the Display Mode label, then choose the Wireframe option from the drop-down menu.

Watch the image in the graphics window as you do this next step. Choose Apply to apply this change. Use the same technique to change the Hidden Edges option to Invisible. Again, watch the graphics window as you Apply this change.

Options on Dialogs

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Applying Perspective to the Part Choose the Perspective tab.

This pane lets you control various aspects of the view in the graphics window. Click the Perspective option to turn it on.

Watch the image of the part as you choose Apply. Now the part is displayed with some perspective so that it looks more natural.

Options on Dialogs Replacing All Values in a Field When you turned on the Perspective option, the Distance field for that option became active. Move the arrow cursor into the Distance text field that is under the Perspective label. The cursor changes into the I-beam display to show that you can use it to indicate a specific insertion point in the text. Double-click in the Distance text field. All of the characters are highlighted (even characters that can't be seen in the field). Key in 300 (but DON'T press the Enter key!). Choose Apply. Now only the characters you keyed in determine the perspective distance. Since you have placed your "eye" closer to the part, it is like looking at it through a wide angle lens.

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Options on Dialogs Inserting Characters in Between Text and Deleting Text Move the I-beam cursor to a position between the decimal point and the zero on its right, then click MB1. The field is focused and the blinking vertical line shows you where text will be inserted.

The blinking insert cursor (the vertical line) shows you exactly where text will be inserted. On the keyboard, type the number 25. The characters are inserted into the string of numbers.

Place the insert cursor to the right of the 5, then press the Backspace key one time. The 5 is removed from the field.

Options on Dialogs Changing Highlighted Text Using the Overstrike Method You can also use the "click and drag" technique to highlight just one or two characters in the text field, then key in new characters to overstrike them. Place the I-beam cursor to the left of the point. Press (and hold) MB1, then drag the highlighting across all the characters on the left.

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When you begin typing, all the highlighted characters will disappear and be replaced by those you are keying in. Key in 945. Only the highlighted numbers are replaced.

Apply this perspective distance value. Since this moves the viewpoint much closer to the part, it is like looking through a wide angle lens.

Options on Dialogs Focusing a Window You need to be aware of another focus signal. You can check the borders around the windows as you move the mouse cursor and click into each different window you have open. The title bar will be "grayed out". Here is a widow with focus.

Here is a window without focus.

Options on Dialogs Accelerators An "accelerator" is a short cut that you can use to execute Unigraphics commands. Click on the View option on the menu bar to display the pull-down menu. Notice the characters at the right side of this pull-down menu. These are the accelerators.

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A few accelerators are a single key (such as F5 for Refresh), but most accelerators are a combination of the Control key and a character. One often used accelerator is the one that will display the Rotate View dialog. Press (and hold down) the Control key, then press the R key.

The Rotate View dialog is displayed.

Cancel the dialog.

Options on Dialogs Closing the Part File You don't want to save any of the changes that you have made on the Visualization Preferences dialog. So you can just close the part file without saving it. Close the part file (with File this lesson.

Close

All Parts), then continue on to the next section of

Controlling the Display of Hidden Edges In any view, you can make hidden edges invisible or display them as dashed or as thin gray lines. You will want to choose various ways to display your part in order to make it easier to select edges.

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In this part of the lesson, you will learn how to: display a part as shaded or as a wireframe image. display a part with hidden edges invisible (to create a realistic looking wireframe image of the part). quickly switch between the different types of images.

Controlling the Display of Hidden Edges Opening the Part File Open

part file uge_image.prt from the uge subdirectory.

This part models a control arm. The right side can be clamped around a shaft. Then, as the shaft rotates, the arm will move a rod that goes through the slot in the left side of the part.

Right now the part is displayed as a shaded solid.

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Controlling the Display of Hidden Edges Displaying More Icons on the View Toolbar To make this exercise a little easier, you can be sure that certain icons are displayed on the View toolbar. Use MB3 to display the Customize dialog (or choose Tools the Commands pane.

Customize), then display

In the Toolbars list box, choose View. In the Commands section, turn on the first seven icons (but leave Navigate off).

The toolbar should now look like this.

Controlling the Display of Hidden Edges Displaying the Shading and Wireframe Icons Scroll down, then be sure that these four icons on (including the separator).

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Close the Customize dialog. Run the cursor over these icons to see their names.

You'll notice that three of these icons have little arrows next to them. You'll use these arrows to open up palettes of icons that will let you set those on the toolbar.

Controlling the Display of Hidden Edges Displaying the Part as a Wireframe "Wireframe" is the name for the type of image that displays all of the edges of a part. Choose the Visible Hidden Edges icon (the current wireframe icon).

Now you can see all of the edges in the part. The system also displays edges of cylinders (which are properly called "silhouettes").

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Controlling the Display of Hidden Edges Displaying the Part With Hidden Edges Invisible Sometimes you want to see the part with only the visible edges displayed (so the part looks like a realistic drawing). Choose the arrow next to the current wireframe icon to display all of the wireframe choices. Then, while this palette is up, use the cursor to display the name of each type of wireframe image.

Choose the Invisible Hidden Edges icon. The system now displays the image with only those edges that are visible.

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Controlling the Display of Hidden Edges Displaying the Part With Gray Thin Hidden Edges Click on the drop-down arrow again, then choose the Gray Thin Hidden Edges icon from the palette of wireframe choices. Many users find that this is the best type of view to work with since you can differentiate between visible and hidden edges, yet select whichever you need.

There is another type of hidden edges available, dashed hidden edges. But it's not used as much as the others.

Controlling the Display of Hidden Edges Going Back and Forth Between a Display of Hidden Edges or Shaded Once you have chosen the type of display of hidden edges that you would like to use, you can quickly change back and forth between that and the shaded image.

Choose the Shaded icon

from the View toolbar.

99 The image is displayed in its shaded version.

If you always use the same wireframe image (like gray thin hidden edges), you can hide the set of wireframe icons from the toolbar and just use the Wireframe icon.

Choose the Wireframe icon. The part is displayed with gray thin hidden edges (the version you were using last).

This is set up this way so you could just switch quickly between shaded and whatever your favorite wireframe image was.

Controlling the Display of Hidden Edges Other Shaded Options You can look at some of the other shaded options that are available. (You will use them in other CAST courses.) Choose the arrow next to the Shaded icon to display the palette with the other shaded options, then use the cursor to reveal their names.

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You can find more information about these shaded functions in the online documentation.

Controlling the Display of Hidden Edges Closing the Part File Close the part file, then continue on to the next section of this lesson.

Controlling Color The Visualization Preferences dialog gave you an opportunity to look at the many different kinds of options that appear on dialogs. At the same time, you can use this dialog to learn more about controlling color.

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In this part of the lesson, you will learn how to: check the color definition file associated with a part file. choose the color you want to use for a background for shaded views and wireframe views. change colors back to the default colors.

Controlling Color Opening the Part File Open

part file uge_color.prt from the uge subdirectory.

This is a small fitting.

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Controlling Color Displaying the Visualization Preferences Dialog Choose the Visualization Preferences icon can choose Preferences Visualization).

from the Visualization toolbar (or you

The Visualization Preferences dialog is displayed. Choose the Color Palette tab.

On the Unix platform, you will see some slight differences in the slider bars, check boxes, etc.

Controlling Color The Color Definition File That Was Used For This Part File The Color Palette pane of this dialog displays all the colors you can use for the display of parts and the background.

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Right under the tabs are some icons that would let you create a new Color Definition File (CDF), open a saved CDF, or save a CDF that you have created.

For this lesson you'll just stay with the default colors.

Controlling Color The Background Color for Shaded Views In this part file, the color behind the part is graduated--dark blue near the top growing lighter toward the bottom. Choose Edit Background (the option near the bottom of the dialog).

The Edit Background dialog is displayed. It lets you control the background color for shaded views and wireframe views.

104 In the Shaded Views section of this dialog, choose Plain.

The background in the graphics window immediately changes to black (that is, no color).

Controlling Color Changing the Color of the Plain Shaded Background Color If you wanted a background color different from black, you could do this. Choose the Plain Color icon near the bottom of the dialog.

The Color dialog is displayed. It gives you 48 basic colors you can choose from along with devices that let you "mix" any color. You can see that the current plain color is highlighted with a dashed box around that icon.

Choose the dark red color above the current color.

OK the dialog. The background immediately changes to the color you selected.

105 Change back to a Graduated shaded view. Cancel the dialog.

Controlling Color The Background Color for Wireframe Views How does the background for wireframe views differ from that for shaded views? Watch the change in the background color as you do this next step.

Choose the Invisible Hidden Edges icon

on the View toolbar.

The background color is now much darker (but still graduated).

Controlling Color Changing the Background Color for Wireframe Views Choose the Visualization Preferences icon can choose Preferences Visualization).

from the Visualization toolbar (or you

On the Color Palette pane, choose Edit Background. The Edit Background dialog is displayed. The default wireframe color is graduated.

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Controlling Color Changing the Luminosity of the Bottom Wireframe Color In the Wireframe Views section of the dialog, choose the Bottom icon.

Change the luminosity of this color by sliding the Luminosity slider upward until the luminosity field reads 120 or so (and watch the color change in the Color/Solid field). — OK the dialog when you have reached the new value.

In Unix, the RGB Editor looks like this.

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Controlling Color Changing Back to the Default Background Colors You can change all of the colors on the Edit Background color to the defaults. On the Edit Background dialog, choose the Default Graduated Colors option near the bottom of the dialog.

The background graduated colors instantly change back to the original graduated colors.

Controlling Color Changing the Plain Color You'll notice, however, that the plain color option did not change. You'll have to do this by hand. Choose the Plain Color icon.

On the Color dialog, choose the Black color icon.

OK the Color dialog. Change the wireframe views to Plain. You can tell from the background of the Visualization Preferences dialog that you are back to a black color for the plain background. OK the Edit Background dialog. OK the Visualization Preferences dialog.

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Controlling Color Displaying the Edit Object Icon on the Utility Toolbar There is another icon that you will find handy to have available. It is located on the Utility toolbar (which is the first toolbar located at the bottom of the window).

Use MB3 to display the Customize dialog. Display the Commands pane. In the Toolbars list box, choose Utility.

In the Toolbars box, scroll down and select Edit Object Display.

Close the Customize dialog. The Edit Object Display icon is now displayed on the Utility toolbar.

Controlling Color Using the Quick Color Palette to Change the Color of an Object The color of the solid in this part file is green. But you can change the colors of objects whenever you need to. First, however, you can display the part as shaded.

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Be sure the part is Shaded. Choose the Edit Object Display icon

(or you can choose Edit

Object Display).

The Class Selection dialog appears.

You'll use this dialog many times in your work to select just the object or objects you need. In this case, you want to select the solid. Choose the Select All option. The part turns white (to show that everything in the graphics window has been selected).

Click MB2 to choose the default action button (the OK button) on the Class Selection dialog. The Edit Object Display dialog is displayed.

You can see that this dialog will let you change many things about the display of objects, including color.

Controlling Color Displaying the Quick Color Palette Choose the Color icon (the green bar) on the Edit Object Display dialog.

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The Color dialog is displayed. The series of colors are called the "Quick Color Palette".

This dialog lets you choose from a set of 30 colors. Notice that the bottom row of colors is the series in a gray scale. The current color of the object you selected is displayed in the large rectangle at the bottom of the color palette. Choose the Yellow icon.

You are immediately returned to the Edit Object Display dialog, which now displays the color you chose.

Apply the Edit Object Display dialog (you want to apply the change but keep the dialog up). The part is now displayed in yellow.

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Controlling Color Changing Back to the Default Color Perhaps you decide that you really don't want the part yellow. You'd rather have it displayed with its original green color. Choose the current Color icon on the Edit Object Display dialog.

You could choose the color you want from the Quick Color palette. But sometimes you may need to choose a color that's not on this palette. Choose More on the Color dialog. The complete color dialog is displayed. You can see at the bottom of the dialog the Color Number and Color Name of the current color. It also gives you values of Red, Green, and Blue mixture that defines this color.

Also, the current color is displayed at the bottom of the color selection column, and there is a white box around that color in the color layout.

Controlling Color Changing Back to the Original Green You could select any color from the color patches on this dialog. If you know the number of the color you want or its name, you could even key one or the other into the fields at the bottom of the dialog.

112 In this case you know that you want to use the default green (which is color number 2). Another way to change colors is to step up or down to the number of the color you want. Watch the white box around the color patches as you click the Down Arrow key until you see 2 in the Number field.

Use MB2 to OK the Color dialog. Use MB2 to OK the Edit Object Dialog. The part is returned to its original color.

Controlling Color Displaying the Part in Wireframe Colors You can quickly change the choice of color palettes.

Choose the Use System Wireframe Color Palette icon toolbar on the dialog.

from the Visualization

The part is now displayed in the green taken from the wireframe palette.

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If you compared the two color palettes, you would see that the system colors (on the left) were not as bright as the wireframe colors. This is because wireframe images are generally displayed against a black or very dark background rather than the graduated background.

It is possible to override the existing Unigraphics NX system palette or part's color palette with your own CDF file. Your system manager would need to do this.

Controlling Color Resetting the System Color Before you leave, you can return to the system render color palette.

Choose the Use System Render Color Palette icon the dialog. Now you are back to the original color settings.

from the Visualization toolbar on

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Close the part file, then continue on to the next section of this lesson.

Selecting Objects This lesson lets you practice different methods of changing the view in the graphics window and selecting features.

In this lesson, you will learn how to: zoom, rotate, and pan views. select features on parts. change views in the graphics window. use layouts (two or more views displayed in the graphics window).

Zooming, Rotating, and Panning Views There are many different ways you can change the view of a part so that you can look at it more closely, or from different angles.

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In this part of the lesson, you will learn how to: scale a view to any size. pan a view (that is, move it right-to-left or up-and-down). rotate a view in order to see its different faces.

Zooming, Rotating, and Panning Views Opening the Part Open

part file uge_rotate.prt from the uge subdirectory.

This is a model of a bolt with a hex head. You can use it to try the different view actions.

Zooming, Rotating, and Panning Views Displaying the Icons You Will Need

116 For the activities in this part of the lesson, you will need to have certain icons available on the View toolbar: the Refresh icon the Fit icon the Zoom icon the Zoom In/Out icon the Rotate icon the Pan icon the Perspective icon. and the Restore icon.

Remember, you can use MB3 and Customize to display the Customize dialog. Use the Commands tab on the Customize dialog to display any missing icons on the View toolbar and to remove the Fit View to Selection icon. Close the dialog.

Zooming, Rotating, and Panning Views Changing the Fit Percentage You'll need to fit the part in the graphics window many times during this lesson. But you won't want the part to fill the entire graphics window. Instead, you'd rather have it fill about 80%.

Choose the Visualization Preferences icon dialog.

to display the Visualization Preferences

Choose the Screen tab. Set the Fit Percentage to 80 or so. HINT: Click four times to the left of the slider knob.

Use MB2 to OK the dialog. Fit the view.

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Zooming, Rotating, and Panning Views Zooming In on Any Portion of a View Using the Zoom Cursor Quite often you will need to get in close on a specific portion of the part. For example, you might want to get a close look at the head of the bolt.

Choose the Zoom icon.

The cursor changes into a little magnifying glass

with a little plus sign in it.

This means to signal that you can now use a "drag rectangle" to define any part of the view you want to zoom in on. Place the cursor above and to the left of the head of the bolt. Press (and hold) MB1, drag the cursor to the bottom right corner to trap all of the head within the drag rectangle, then release MB1.

Now only the area you designated appears in the graphics window.

Fit the view. Click MB2 to dismiss the Zoom option.

Zooming, Rotating, and Panning Views Zooming Out on a View to Make It Smaller You can shrink the part in the graphics window by zooming out (like you would with a zoom lens on a camera). You can also enlarge it by zooming in.

Choose the Zoom In/Out icon.

The cursor changes to a magnifying glass

with both a plus sign and minus sign in it.

118 Place the Zoom In/Out cursor in the center of the shaft, press (and hold) MB1 then move the cursor upward. The image gets smaller.

The little line from the Zoom In/Out cursor gives you an idea of the amount of the zoom.

Zooming, Rotating, and Panning Views Zooming In on a View to Make It Larger This time place the Zoom In/Out cursor in the center of the bolt head, press (and hold) MB1, then move the cursor downward. This time the image gets larger.

Did you notice that the origin of the little line from the Zoom In/Out cursor shows you the center of the enlargement? Generally you will want to place the Zoom In/Out cursor on the object you want to make larger or smaller.

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Fit the view. You'll notice that the cursor has remained the Zoom In/Out cursor (just in case you want to do more zooming). Click MB2 (the OK button) to release the cursor back to its normal graphics window version.

Did you notice that the Zoom In/Out icon also turned off?

Zooming, Rotating, and Panning Views Quick Zooming There is a quicker way to zoom a view either larger or smaller. Place the cursor in the center of the part. On the mouse, press (and hold) MB2 then MB1. Move the mouse vertically. The cursor changes into the Dynamic Zoom In/Out cursor and the part gets smaller or larger depending on your mouse movement.

You can also do this by pressing the Control key along with MB2, then moving the mouse. Zooming In Unix You can use the same method for quick zooming if you are using Unix. But you can also use the slider on the left border of the graphics window to zoom in or out.

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Zooming, Rotating, and Panning Views Panning (Moving) a View You can pan (move) a view in any direction without changing its scale. The word "pan" comes from the word "panorama". It describes the movement of a video camera from side-to-side or up-and-down.

Choose the Pan icon

from the View toolbar.

The graphics window cursor changes into the "panning" cursor (a little hand).

Place the pan cursor over the part, press and hold MB1, then drag the cursor around in the graphics area. Where ever you "grab" the part, it will follow your cursor. This is especially helpful after you enlarge a view then need to move the part you want to work with into the center of the graphics window.

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Fit the view. Click MB2 to change back to the normal graphics cursor.

Zooming, Rotating, and Panning Views Quick Panning Just like quick zooming, you can use the mouse to quickly pan the view. On the mouse, press (and hold) MB2 then MB3. Move the mouse in a circular motion. The cursor turns into the Dynamic Pan cursor, and the part follows your mouse movements.

You can also do this by pressing the Shift key along with MB2, then moving the mouse.

Zooming, Rotating, and Panning Views Rotating a View Many times you will want to look at a part from different angles, especially to see a face that is hidden in the current view.

Choose the Rotate icon

from the View toolbar.

The cursor turns into the Rotate cursor.

Place the cursor near the middle of the part. Press (and hold) MB1, then slowly move the cursor upward and downward. The part rotates around an axis that goes horizontally through the center of the graphic window .

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Place the rotate cursor near the middle of the part again. Press and hold MB1, then move the cursor slowly to the left and right. This time the part rotates around an axis that goes through the graphics window vertically. Experiment with the cursor movements until you can make the part rotate the way you want it to.

Zooming, Rotating, and Panning Views Restoring a View to its Original Orientation If you used the icon to Fit this view, it would remain in its rotated orientation. Instead, you often want to return it to its original state.

Choose the Restore icon Operation Restore).

from the View toolbar (or you can choose View

The part is restored to the view that you had before you changed it.

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If the cursor is still in its Rotate mode, use MB2 to change it back to the normal graphics window cursor.

Zooming, Rotating, and Panning Views Quick Rotation

These techniques may not work with a two-button mouse. There are several different ways you can quickly rotate the view using just the mouse. Move the cursor anywhere into the central area of the graphics window. Press (and hold) MB2, the move the mouse. The cursor turns into the Dynamic Rotate cursor, and the part rotates in various directions depending on your mouse movements.

Restore the view

when you are ready to continue.

Zooming, Rotating, and Panning Views Rotating the View Around the Horizontal Axes of the Graphics Window If you want to limit the rotation of the view to just one screen axis, you can bring up the Dynamic Rotate cursor near an edge of the graphics window.

124 For example, say you wanted to rotate the part around a horizontal screen axis (so the part will appear to rotate end over end). Place the cursor very near the left or right edge of the graphics window. Press MB2 then move the cursor vertically to rotate the part around the horizontal graphics window axis.

Restore the view.

Zooming, Rotating, and Panning Views Rotating the View Around the Vertical Axis of the Graphics Window You can rotate the part around a vertical screen axis with the "vertical screen axis" rotation cursor. Place the cursor very near the bottom edge of the graphics window. Then, keeping MB2 held down, move the mouse back and forth to rotate the part around the vertical graphics window axis.

Restore the view.

Zooming, Rotating, and Panning Views Rotating the View Around the Z Axis of the Graphics Window You can also rotate the part about a screen axis that comes straight out at you (the "Z screen axis" cursor).

125 Place the cursor very near the top edge of the graphics window. Then, keeping MB2 held down, move the mouse back and forth to rotate the part around the graphics window Z axis. Restore the view

when you are ready to continue.

Zooming, Rotating, and Panning Views Using the Special Rotate Cursors Along With the Rotate Icon It's not readily apparent, but once you choose the Rotate icon, you can change from one type of rotation cursor to the next by just placing the cursor in the correct location.

Choose the Rotate icon. Move the cursor near the top edge of the graphics window. You get the Rotate Around Z Axis cursor.

Move the cursor near the left edge of the graphics window. You get the Rotate Around X Axis cursor.

Move the cursor near the bottom edge of the graphics window. You get the Rotate Around Y Axis cursor.

Click MB2 to dismiss the Rotate option.

Zooming, Rotating, and Panning Views

126

The View Pop-Up Menu There is a menu that you can display in the graphics window that contains many of the options you have used up to now. Place the cursor anywhere in the graphics window except directly on the part, then click MB3. The pop-up menu is displayed. You can see it contains the options (commands) you have just been using (Fit, Zoom, and so on).

Sometimes you will find it easier to choose an option from this pop-up menu than to choose an icon from a toolbar. It also contains some options that are not on the toolbar. (There will be an example in this lesson).

Zooming, Rotating, and Panning Views Rotating a Wireframe Image Change the view to Invisible Hidden Edges. You can see that this part file uses a plain (black) background for wireframe images.

127

Choose the Rotate icon

from the View toolbar (or use MB2 and mouse movement).

Move the Rotate cursor diagonally across the graphics window. All of the edges (including the silhouetted edges) of this part remain in place as you rotate it. So the appearance of the bolt becomes quite distorted!

Zooming, Rotating, and Panning Views Updating a Display Whenever a wireframe display becomes distorted, you can have the system update it to a correct image. If you need to, click MB2 to get out of the Rotate cursor. Be sure the cursor is inside the graphics window but NOT on the part, then click MB3 to display the View pop-up menu. Choose the Update Display option.

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The wireframe image is reconstructed to show the correct silhouette in its current orientation.

Zooming, Rotating, and Panning Views Returning to the Original Orientation. Restore the view. The wireframe image is returned to the correct orientation, but its edges are not correctly displayed. Use the MB3 pop-up dialog to Update Display.

Close the part file.

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Selecting Features In Unigraphics NX, the word "feature" means an associative object. It is an object that remembers the inputs and the operations that were used to create it. Features include such things as blocks, holes, slots, pockets, blends, chamfers, and so on. In this lesson, you are going to concentrate on selecting just a few features.

In this part of the lesson, you will learn how to: find the names of features that were used to create a part. use the selection ball to select a specific feature. use "prehighlighting" and "QuickPick" to select the feature you want. use the "dynamic pop-up menu" to change a feature.

Selecting Features Opening the Part File Open

part file uge_features.prt.

This part was chosen for this exercise because it is very simple. The counterbored hole goes all the way through the part. There is a groove on the right side, and the left back corner has been chamfered.

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Selecting Features Using the Model Navigator to Look at the Features in a Unigraphics NX Part As you'll see in a moment, this solid model is made up of five different types of features. Windows users can display the Model Navigator at any time by using the tab on the resource bar. (Unix users can use the Model Navigator icon.) However, in order to see it AND the CAST lesson, you will need to detach it and move it to a location where it doesn't block your view of the lesson or the part. (You move and size it like any window.) You might want to read ahead in these instructions so that you will know what to do with the Model Navigator window in case it covers up some of the CAST window. Place your cursor over the Model Navigator icon (visible on the right edge of the Unigraphics NX window).

Click MB3, then select Undock from the little pop-up menu.

Adjust the size of the Model Navigator window if you need to.

Selecting Features Setting Up the Model Navigator Window First, you need to expand the Feature Names column so that you can read the names of the features.

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You would use a different procedure on Unix. Move the cursor over the column division mark next to the title of the Layer column so it turns into the Move cursor.

Press (and hold) MB1 then move the column mark to the right until you can read all of the feature names.

Shrink the horizontal width of this window from the right side until you can read just the layer numbers.

The BLOCK(0) feature should be at the top of the list of features. If the order is different in your Model Navigator window, click once on the Feature Name title bar to reverse it.

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Selecting Features Moving the Model Navigator Window You will need to move the undocked window to a good location (say at the lower right hand corner of the graphics window). Place the cursor in the title bar of the Model Navigator window. Press (and hold) the Control key with MB1, then move the entire window downward to a good location. When you are satisfied, release MB1 and the Control key.

Selecting Features Features in the Model Navigator The Model Navigator shows that there are five different features in this model (with the Datum Plane feature used twice).

This is how each feature affects the model: The block feature defines the overall shape of the part. The rectangular slot feature was placed on the right face of the block feature. The chamfer feature cuts off the left back corner of the block feature. The counter bored hole feature was created on the bottom face of the block feature. It goes all the way through the block so that the hole appears on the top face and the counterbore on the bottom face.

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There are two features in this part file that you can't see—the two datum planes. These are construction objects that were used to center the counterbored hole, then made invisible. (You'll learn more about this type of feature later.)

Selecting Features Looking At a Different Order on the Model Navigator There are several ways you can look at the relationship between features in a part. Right now you are looking at the order in which features were created (called "timestamp" order). Place the cursor on the Feature Name heading, then click MB3. The Model Navigator pop-up menu is displayed. From the pop-up menu, choose Quick Look.

(In this part file Quick Look and Full Look will be the same.) This arrangement shows the dependency (parent-child) relationships between features: The block feature defines the overall shape of the part. All of the other features were created on the block feature. There are no other dependencies between features.

134 As you begin working with more complex parts, you will find the Quick Look display very helpful in understanding their construction. Use the Close icon on the Model Navigator window to dismiss it.

When you opened the Model Navigator, the system may have displayed the Model Navigator toolbar. But you won't need to use it in this lesson. If you need to, use the Close icon on the Model Navigator toolbar to close it.

Selecting Features The Display of the Solid In order to see and select some of these features, you will want to display the part with thin gray hidden edges.

Choose the Thin Gray Hidden Edges icon. Now you can see the outline of the chamfered face and the counterbore portion of the counterbored hole.

You can also see why a plain black background was chosen for wireframe displays in this part file.

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Selecting Features Preparing to Select Features In this lesson you will begin using the selection ball to select various features. Move the cursor into the graphics area. The selection ball (or more correctly, the "object selection cursor") is a small crosshairs with arc symbols that define a circular area.

You can use the Selection toolbar to filter your selections to specific objects. Be sure the Selection toolbar is displayed. You'll notice that many of the icons on this toolbar are grayed out. (They would become available if you went into another application.)

For this lesson you want to be able to select only features.

Choose the Select Features icon

if you need to.

Selecting Features Prehighlighting In order to help you select the object or feature you want, the system will prehighlight an object before you actually select it. Place the cursor over the groove in the right face of the part.

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The edges of the groove feature turn magenta (the preselection color). If you clicked MB1 when this feature is prehighlighted, it would be selected. The preselection color is set on the Color Settings pane of the Visualization Preferences dialog.

Selecting Features Selecting a Feature You can begin by selecting the block feature Place the cursor on the front face of the block feature so that all of the edges of this feature prehighlight.

Notice that the Status Line at the bottom of the Unigraphics NX window gives you the name of the feature that you are going to select—BLOCK(0).

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The zero in parentheses tells you that this was the first feature created in this part file. Click MB1 to select the block feature. All edges that are on the faces of the block feature turn white to show that you have selected the correct feature.

Selecting Features Deselecting a Selected Feature In case you find that you have selected the wrong feature, how do you "deselect"? Hold down the Shift key as you select the front face of the block feature again. The block feature unhighlights (that is, all of its visible edges are displayed with green again.

This deselection action is often called "Shift-Select". Another way to do this is to use the Escape key.

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Selecting Features Selecting a Feature (Using QuickPick) If you wanted to select the chamfer feature from the graphics window, you would need to select the chamfered face at the left back of the part.

But if you place the cursor on this face, you will also pick up the top face of the block. You must tell the system which face you actually want to select. Move the cursor to the middle of the chamfered face and leave it there until it turns into the "Confirmation" cursor (a cross with three little dots).

This cursor (also called the "Multiple Selectable Objects" cursor) warns you that more than one object lies under the cursor. In this case it's the block feature and the chamfer feature. Press MB1 to display the QuickPick dialog.

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Selecting Features Selecting the Feature You Want Since there were only two possible features under the cursor, you only get two numbers on the QuickPick dialog. Place the arrow cursor over number 1 on the QuickPick (but don't select anything yet). The name of the feature you would select if you clicked the first number appears under the QuickPick. (It also appears in the Status Line.) Also, all of the edges of that feature prehighlight.

Place the arrow cursor over number 2 but don't select anything. Now the object represented by this number (the chamfer feature) is named and prehighlighted.

Click MB1 on number 2 to select the chamfer.

Selecting Features Another Way to Use QuickPick As you get more comfortable with selecting objects on a part, you will want to use the mouse buttons rather than selecting numbers from the QuickPick dialog. Press the Escape key to deselect the object. Move the cursor to the middle of the chamfered face again, and leave it there until it turns into the Confirmation cursor.

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Press MB1 to display the QuickPick dialog.

The first number on the dialog is highlighted. And the outline of the Block feature is prehighlighted. If the Block feature were what you wanted to select, you could OK your pick with MB2. However, if you wanted to see what object would be selected with the second number, you would do this. Click MB1 with the cursor still over the model (outside the QuickPick box). The next object under the cursor is prehighlighted.

Let's say that this is the object you wanted to select. OK the prehighlighted object by clicking MB2. The chamfer feature is highlighted (white, the system color) to show that it is now selected.

141 You can also use the arrow keys to highlight the numbers on the QuickPick dialog. Use the Escape key to deselect the Chamfer feature.

Selecting Features Stopping the QuickPick What if you change your mind while you are in the midst of selecting an object? You can just delete the QuickPick dialog before you select an object. Move the cursor to the middle of the chamfered face again, and leave it there until it turns into the Confirmation cursor.

Click MB1 to display the QuickPick dialog. To dismiss the QuickPick dialog, choose its Close button.

The part is unhighlighted, showing that no object has been selected.

Selecting Features Setting the Preference for the Size of the Selection Ball Some users may find that the size of the selection ball is either a little too small or a little too large. But the system will let you choose any one of three sizes. Choose Preferences

Selection to bring up the Selection Preferences dialog.

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Right now the size (radius) is set to Medium.

Click on the option to display the possible sizes, then choose Small.

OK the dialog. Move the crosshairs around in the graphics window to compare its current size with its previous size.

Selecting Features Returning the Selection Ball to its Default Radius Some of the parameters on the dialogs you have seen are "session dependent". That is, they revert to their default values whenever you quit Unigraphics NX. If you would rather use the default size for the selection ball for the rest of these exercises, you can do this. Use Preferences

Selection to bring up the Selection Preferences dialog again.

Change the Radius back to Medium.

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Selecting Features Using Full Screen Crosshairs It is not often that you will need to line up objects when you are developing your model, but sometimes you will need to, especially if you create dimensions or notes on the drawing of a part. The option that changes the cursor into its full screen version is on this same dialog. Choose the Crosshairs option to turn it on.

OK the dialog. Now the crosshairs fill the graphics window.

Selecting Features Other Settings on the Selection Preferences Dialog You can look at a few other options on the Selection Preferences dialog. Try using the accelerator Control+Shift+T to bring up the Selection Preferences dialog (or just use Preferences Selection).

144 You would use this dialog to turn the preselection action off. You could also change the amount of delay of the appearance of the magenta color as you move your cursor over objects.

You could change the amount of delay that the cursor takes to change into a "multiple objects" cursor.

If you didn't want to see the QuickPick near your cursor, you could have the system place it in the upper left hand corner of the graphics window instead.

There are some other settings on this dialog that will be discussed in other lessons. While you still have this dialog up, you can turn off the full screen crosshairs. Choose the Crosshairs option to turn it off.

OK the dialog.

Selecting Features Selecting General Objects on a Part Sometimes you will need to be able to select very specific objects on a part (like a face or an edge).

Choose the Select General Objects icon. You can take a look at the types of objects you can select. Click on the Type filter to display the possible object types you can select (you will have to scroll to see them all).

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As you saw, there are many different types you can limit your selection to.

In this case you want to limit your selection to just faces. Set the Type Filter option to Face.

Run your cursor over various faces on the part to see how this selection would work. (You will see only the word "Face" appear in the Status Line.)

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Selecting Features Using MB3 to Display the Modeling Pop-Up Menu As you move into the other applications, you will often need to edit specific parameters of a feature. Generally you will call up the dialog you would need. But there is an easier way to edit feature parameters. In order to demonstrate this to yourself, you will need to be in the Modeling application.

Choose the Modeling icon Application Modeling).

from the Application toolbar (or you can choose

Change back to the Select Features icon on the Selection toolbar.

Use the QuickPick to select the counterbored hole.

Place the cursor over the selected feature, then click MB3. The pop-up menu appropriate for this feature appears.

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Selecting Features Choosing an Option from the Modeling Pop-Up Menu This menu allows you to perform various operations on this feature. edit its parameters (to change its size). edit its positioning parameters (to move it to a different location on the part). suppress it (that is, temporarily remove it from the model). copy or delete it. check its properties. Choose Edit Parameters on the menu.

The Edit Parameters dialog is displayed.

Choose Feature Dialog. The dialog changes to display the three parameters that define the size of this part.

Notice that the system has displayed the two datum planes that were used to position this counterbored hole feature along with the values of the three part parameters.

148 Cancel the dialog. Close the part, then continue on to the next section.

Changing Views Up to now you've looked at the part with whatever view the designer chose to use (mostly a trimetric view). The system provides for six standard views plus an isometric view and a trimetric view.

As you know from using the Rotate cursor, you can actually look at a part from any angle. But being able to quickly change to a standard view will often help you visualize the part correctly. In this part of the lesson, you will: orient the view to different standard views. replace the current view with a different standard view.

Changing Views Opening the Part File Open

part file uge_views.prt.

149 This is a part you've worked with before.

It will be a good part for this lesson because you will easily be able to figure out which way each view looks at it.

Changing Views Orienting the Current View to Another Standard View Using the Toolbar At the right end of the View toolbar, there is a symbol of a little cube with a chamfer on its top right edge.

This is the symbol for the view you are currently looking at, a trimetric view. The name of this view appears at the bottom of the graphics window: TFR-TRI.

The TFR stands for "top-front-right". The word "WORK" just tells you that this is the "work" view. This only becomes important when you are using view layouts (which is taught in a later lesson). People like to work with a trimetric view because the edges of a square shape won't overlap as they may in an isometric view.

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Click on the drop-down arrow next to the view icon to display all of the standard views that are available.

Use the cursor to display the name for each view icon.

Changing Views Choosing the View Choose the Isometric icon

from the drop-down menu.

The system visually rotates the part into a trimetric view. However, the view name displayed at the bottom of the graphics window has NOT changed. It still says you are in a trimetric view.

The view has just been oriented into a trimetric view. It has NOT been replaced.

Changing Views Choosing Other Views

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Choose the icon for the Front view. The view rotates into a front view orientation.

Choose the Top icon. The view rotates into a top view orientation.

Changing Views Orienting a View Using the MB3 Pop-Up Menu You can also use the MB3 pop-up window to orient your view. Place the cursor in the graphics window (but not on the part). Click MB3 (and leave the pop-up menu displayed). Place the cursor over Orient View (but don't select it), and leave the menu up.

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This menu has the same icons that you were using on the drop-down menu from the toolbar. Click anywhere in the graphics window to dismiss the menus.

Changing Views Replacing the Current View With a Standard View The Orient View option is especially useful whenever you are working with very large models. It doesn't take too much memory to rotate the view into a different orientation. However, if you replace the view of a large model, it will sometimes take the system a little while to do it. The part you are working with right now is small enough that you won't see any difference between the two methods. But there are some other differences that might be important to you. Click MB3, run the cursor down to Replace View and choose TFR-TRI from the cascade menu. The TFR-TRI view replaces the previous view.

And the name of this view is now displayed in the graphics window.

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Changing Views Replacing the Current View With Another Standard View Use the MB3 pop-up menu to replace the current view with a Right view.

The view changes to a right view, but it is displayed as a wireframe image.

When this part was saved, this standard view was set to gray thin hidden edges.

Changing Views Preparing to Create a Custom View Occasionally you will want to be able to choose a view that is NOT a standard view. Use the MB3 pop-up menu to replace this view with the standard trimetric view. Rotate

the view to an odd angle (it's exact position is not important).

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Changing Views Creating a Custom View You would like to be able to return to this view at any time. Choose View

Operation

Save As.

(The Save Work View icon is available on the View toolbar.) The Save Work View dialog is displayed.

Click in the Name field to highlight all of the characters.

Key in an appropriate name, such as ROTATED. (Use all caps and NO spaces.)

OK the dialog.

155 The name you keyed in now appears at the bottom of the graphics window.

Changing Views Replacing the Current View With a Custom View Use the MB3 pop-up menu to replace the view with a TFR-TRI view. You must be able to select the name you gave to your rotated view. Use MB3 to display the view pop-up menu, then choose Replace View VIEWS.

CUSTOM

The Custom Views dialog is displayed. It has the same standard view icons you used earlier, but it also displays the name of every saved view in this part file.

Choose the name of your own view, ROTATED. You are immediately returned to your saved view. Close the Replace View dialog.

Changing Views Using a Perspective Projection The project method you have been using up to now is called "parallel projection". This method sometimes causes an optical illusions which make square-shaped objects appear a little distorted. When objects are viewed using perspective projection, they appear smaller as they are farther away. All parallel lines have the same "vanishing point." So the part will look like it would in

156 a photograph. This would be especially helpful whenever you were working with large models (such as a motor block). Use the MB3 pop-up menu to replace the view with custom view TFR-ISO-BACK. Due to the perspective, the left end of the part appears larger than the right.

Choose the Perspective

icon on the View toolbar.

Close the Replace View dialog. Now the part looks more like it would in a photograph (with its left end appearing a little smaller than its right end).

Changing Views Closing the Part Close the part file.

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Using Standard Layouts Unigraphics NX gives you various standard layout patterns that you can call up at any time.

In this part of the lesson, you will learn: how to choose a layout. how to replace a view in a layout. about unique view names. about saving a layout that you've changed. about creating new layouts.

Using Standard Layouts Opening the Part Open

part file uge_layouts.prt.

Using Standard Layouts Looking at the Available Layouts A layout is a collection of views. For example, you could display four views at one time in the graphics window. You might want to display a top view, a front view, and right side view and a top-front-right isometric view.

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Choose Format

Layout

Open.

The Open Layout dialog is displayed.

It lists five of the six layouts that are available.

(The layout that is NOT listed displays nine views. It is not included on this dialog because it is so seldom used.) Here is the arrangement of each layout listed on the dialog.

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Using Standard Layouts Choosing the Layout You Want You would like two views of the part displayed side by side. Choose the layout called L2 (side by side).

OK the dialog. In the layout you get a FRONT view in the left frame and a RIGHT view in the right frame. (These are the default views for this standard two view layout because they are so often used together.)

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Using Standard Layouts The WORK View In each layout only one view is labeled as the WORK view. In the current layout, the FRONT view is the work view.

There are some operations that you will use in other applications that are "work view dependent". But you can use the MB3 pop-up menu and the cursor location to rotate, pan, zoom, shade, or fit any view.

Using Standard Layouts Replacing a View in a Layout Using MB3 You can replace any view in a layout.

161 Let's say you would rather have a LEFT view where the FRONT view is now.

Place the cursor in the frame of the FRONT view. Click MB3 to bring up the MB3 pop-up menu, then choose Replace View

LEFT.

View LEFT is now displayed in the lower left frame.

Using Standard Layouts Unique View Names What would happen if you tried to place two LEFT views in a layout? Since the system will not let you create two views with identical names, it would give the duplicated view a unique name (by adding a number after it).

Using Standard Layouts Saving a Revised Layout Under Its Own Name Suppose you thought that the views in a layout that you have changed would be better for your work than the views that were supplied in the standard layout. If you were not concerned about keeping the original views in a layout, you could just save the layout as it is under its current name by using Format Layout Save. However, if you wanted to retain the new version, you would need to save the altered layout under its own name.

162 Choose Format

Layout

Save As

In the Name text field, key in an appropriate name for this layout: left-right (lower case is OK, but NO spaces!).

OK the dialog. Choose Format

Layout

Open.

The Open Layout dialog now displays the name you gave the new layout.

OK the dialog. Your new layout would be saved when you saved the part file.

Using Standard Layouts Creating New Layouts If desired, you can create instructions for your own layout. You would choose Format

Layout

New to display the New Layout dialog.

The system will supply a default name or you can use one of your own. The option menu will give you a choice of six layouts. (There is only one layout you have not already seen—the 9 view layout.)

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The nice thing about this method is that you can assign different types of views to the layout.

Using Standard Layouts Closing the Part Close the part file, then continue on to the next lesson.

Manipulating the WCS In this lesson, you will learn how to manipulate the work coordinate system (WCS) in order to accomplish certain actions. In this lesson you will: work with the dynamic WCS by moving it, rotating it and reorienting it, and repositioning it. work with the work plane by emphasizing it and displaying a grid on it.

Working With the Dynamic WCS The Work Coordinate System (WCS) is the one you will use for construction when you want to determine orientations and angles of features as you build your solid. The "C" on the name for each axis stands for "current".

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Also, each axis is a different color to help you orient it in modeling space. In this part of the lesson, you will: see how the "right hand rule" applies to the WCS. work with the WCS toolbar. turn the display of the WCS on or off. use the various "handles" on the dynamic WCS to rotate it and to move it to any location on the part or in modeling space. align the WCS with edges on the part. discover the importance of the "absolute coordinate system" and learn how to find it.

Working With the Dynamic WCS The Right Hand Rule All coordinate systems in Unigraphics NX are right-hand rule coordinate systems.

This means that if the origin of the coordinate system is in the palm of the right fist, the outward extension of the thumb corresponds to the positive X axis, the upward extension of the index finger corresponds to the positive Y axis, and the outward extension of the middle finger corresponds to the positive Z axis.

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Working With the Dynamic WCS Opening the Part File Open

part file uge_wcs.prt from the uge subdirectory.

This is the same part you were working with in the previous lesson.

Change to Gray Thin Hidden Edges.

Working With the Dynamic WCS Displaying the WCS Icons on the Utility The Utility toolbar contains various WCS icons. For this lesson you'll need to be able to use these icons on the Utility toolbar. 1. WCS Dynamics

166 2. Orient WCS 3. Display WCS

With the cursor in the toolbar area, click MB3 to display the Customize dialog. Choose the Commands tab. Choose the Utility option in the Toolbars list box. Turn on the icons you need. Close the dialog. Be sure the toolbar is in the toolbar area below the graphics window.

Working With the Dynamic WCS Turning the Display of the WCS On or Off Right now the WCS is not displayed, so the Display WCS icon is not "pressed down" (that is, turned on).

Click on the Display WCS icon to turn it on. The WCS appears at the front lower left hand corner of the part.

The WCS was used to define the location and origin of the Block feature (which is the basic feature of this part).

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Working With the Dynamic WCS The Handles on the Dynamic WCS When you choose the Dynamic WCS icon, the WCS will be displayed with its various handles. 1. 2. 3. 4.

The yellow square at the origin of the WCS is the Origin handle. Each colored axis is an Axis handle. The yellow circles at the ends of each axis are the Translation handles. The solid yellow circles on the arcs between each set of axes are the rotation handles.

As you'll see in a moment, you can use these handles to move and rotate the WCS to any location on the part or in modeling space.

Working With the Dynamic WCS The Icon Option for the Point Constructor Dialog As soon as you display the Dynamic WCS, a small icon will appear in the upper left corner of the graphics window.

These specific toolbars are called "icon option" toolbars. They always appear in the same place in the Graphics window. In this case you will use it to display the Point Constructor dialog.

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You can then use this dialog to define an exact location of the WCS on the part or in modeling space.

Working With the Dynamic WCS Using WCS Dynamics Choose the WCS Dynamics icon. The WCS changes into its Dynamic WCS display.

The icon option for the Point Constructor appears along with the Snap Point toolbar. If you don't see the Snap Point toolbar, you will need to display it: Place the cursor in the toolbar area. Click MB3, then turn on Snap Point.

Drag the Snap Point toolbar to a location near the top of the graphics window (but don't dock it).

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You'll use this toolbar to define exactly what type of points you'll be able to choose. Some of its icons are turned on by default. There are symbols on these icons for end points, mid points, control points, and so on. You'll learn more about these icons as you go through this lesson.

Working With the Dynamic WCS Dynamically Moving the WCS to a Specified Point in Modeling Space You want to move the WCS to a location 50 mm along its positive XC axis and 25 mm in front of the part (that is, along its negative YC axis).

Choose the Point Constructor icon (in the upper left hand corner of the graphics window).

The Point Constructor dialog is displayed.

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Working With the Dynamic WCS Keying in the Point Location in Modeling Space You want to move the WCS to a location that is 50 mm along the positive XC field and 25 mm in front of the part. (This will center the WCS in front of the part.) Also, you don't want the origin of the WCS to be above or below its current plane.

In the XC field on the Point Constructor dialog, key in 50. Press the Tab key to focus the next field. In the YC field, key in a negative value, -25. Leave the ZC field set to zero. OK the dialog. The WCS has been moved to the location you defined.

Turn off the WCS Dynamics icon.

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Working With the Dynamic WCS Dynamically Displaying the WCS You can also move the WCS "manually" to any position on the current XC-YC plane. Since you didn't key in a ZC value on the Point Constructor, the WCS is still on the original XC-YC plane. Move the cursor over the WCS. It prehighlights. Double-click on the prehighlighted WCS. It turns into the Dynamic WCS. Did you notice that the WCS Dynamics icon on the WCS toolbar has also been turned on?

Working With the Dynamic WCS Dynamically Dragging the WCS to Another Location on the Current Plane Move the cursor over the Origin handle. The Origin handle prehighlights, and the cursor changes into a "Dragable" cursor. Also, a little "Move In Any Direction" symbol appears near it.

With the cursor over the Origin handle, press (and hold) MB1, then drag the cursor to a location away from the part. If you looked at a front view of the part, you would see that the WCS has remained on the XC-YC plane.

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Working With the Dynamic WCS Control Points on Edges Normally you will want to move the WCS to a specific location on a part rather than keying in a specific distance from its current location. The system creates control points that you can select on each edge you see in a wireframe image. You'll see control points at these locations on edges or curves when you prehighlight an edge.

Also, the Point Constructor dialog will let you filter for a specific type of point. (You'll get more details about this later).

Working With the Dynamic WCS Moving the WCS by Selecting an End Point Let's say you need to have the WCS placed at the top front left corner of the part. But you want to keep it in its current orientation (with its XC axis parallel with the long side of the part).

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On the Snap Point toolbar, turn off every icon, then turn on the End Point icon.

Place the cursor over the Origin handle of the Dynamic WCS. Press (and hold) MB1, then drag the origin of the WCS to an endpoint at the top front corner of the part. When the point is prehighlighted, let go of MB1. When the system detected one of the endpoints at this corner, it displayed the cursor as a "Snap To Point" cursor and you see a little "End Point" symbol next to it.

Working With the Dynamic WCS Snapping the Dynamic WCS to a Selected Point Let's say that you want to move the WCS to the center of the arc in the top face of the part. (But you still want to keep the WCS in its current orientation).

174 On the Snap dialog, turn on the Arc Center icon. (It's OK to leave the End Point icon on.)

Now you are limited to selecting ONLY the arc centers of circular edges on this part and end points. Move the selection cursor over the top circular edge of the counterbored hole feature until you see a "Point" symbol appear near the cursor, then choose MB1.

The WCS moves to the arc center point.

Working With the Dynamic WCS Aligning an Axis of the WCS With an Edge Sometimes the direction of the axes of the WCS becomes very important. For example, you plan to use a procedure that requires the XC axis to be parallel with the top angled edge of the chamfer.

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First you need to define the axis you want to change. Select the XC axis of the Dynamic WCS. The axis turns white. Select the angled edge at the back left of the part. The WCS instantly rotates so that the XC axis is now parallel with the edge you selected.

Working With the Dynamic WCS Flipping the WCS 180 Degrees What if you really needed to have the XC axis pointing in the opposite direction (toward the front of the part but still parallel with the angled edge)?

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You could flip it. Double-click on the open circle at the end of the XC axis. The WCS instantly flips around the ZC axis.

This rotating action also displays a "dynamic input box" near the end of the XC axis. It consists of a little dialog with two values displayed.

Working With the Dynamic WCS Rotating the WCS By Dragging a Handle Move the cursor over the Rotation handle (the solid yellow circle) between the XC axis and the YC axis. The handle prehighlights, and the cursor changes into the Dragable cursor and a little "Rotate" symbol appears near it.

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Press (and hold) MB1, then drag the cursor around the WCS. (It will jump in 45 degree increments to each new orientation.) You can change the snap value at any time. The dynamic input box should still be up. (If it isn't, just rotate the WCS a little more.) Click twice in the Snap value of the dynamic input box so that you select all of the characters (white characters on a dark background).

Key in a value of 10 then press Enter. Now, select the same Rotate handle and rotate the WCS some more. This time the WCS snaps in 10 degree increments as it rotates around the ZC axis.

Working With the Dynamic WCS Rotating the WCS to a Specific Angle You can rotate the dynamic WCS to any specific angle by keying in a value. Right now the rotation handle between the XC and YC axis is highlighted. So the system assumes that you want to rotate the dynamic WCS around the ZC axis. Double-click in the Angle field to focus it and select every character. Key in a value of 25 (and press Enter).

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Working With the Dynamic WCS The Absolute Coordinate System

The Absolute Coordinate System is the coordinate system from which all objects are referenced. Because this coordinate system is a fixed coordinate system, the locations and orientations of every object in Unigraphics NX modeling space are related back to its origin. The Absolute Coordinate System (or "Absolute CSYS") also provides a common frame of reference between part files. This means that an absolute position at X=1, Y=1, and Z=1 in one part file is the same location in any other part file. There are other types of coordinate systems that you will work with occasionally, but the working coordinate system and the absolute coordinate system are the two you will refer to most often.

Working With the Dynamic WCS Finding the Absolute CSYS in the Part Before you move the WCS around some more, you would like to know where the absolute 0,0,0 location of this part is.

Choose the Orient WCS icon. The dynamic WCS is turned off and the CSYS Constructor dialog is displayed. The icons at the top will let you choose different methods for moving and orienting the WCS. Choose the Absolute CSYS icon

on the dialog.

The system gives you a preview image of where the WCS will be placed and how it will be aligned.

179 OK the dialog (use MB2). The WCS appears at the absolute CSYS.

Its location and orientation show that it was used to create the solid block.

Working With the Dynamic WCS Translating the WCS Along an Axis

Sometimes you will need to move the WCS along an edge a certain distance. For example, you might need to have the WCS placed at a location along the top front edge that is 25 mm from the left side of the part.

Since there is no control point at this location, you can drag the WCS along that edge after you place it at a control point.

Choose the Dynamic WCS icon. Move the dynamic WCS to the control point (end point) at the top front corner on the left side of the part.

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Working With the Dynamic WCS Dragging (Translating) the WCS Select the Translation handle (the open circle) at the end of the XC axis. The dynamic input box appears, displaying fields for the translation values Distance and Snap. Also, the cursor turns into the Move cursor and a symbol for movement along an edge appears.

Drag the WCS along its XC axis until the Distance value is 25.

Click MB2 to OK the current position of the WCS (and turn off the WCS Dynamics icon).

181 Another way to have done this would be to just key in the distance value. Remember, you are actually translating the dynamic WCS along an axis, not an edge. Close the part, then continue on to the next section of the lesson.

The Work Plane The XC-YC axes of the WCS define the "work plane". That is, if you created an object it would be placed on the plane defined by these axes.

In this part of the lesson you will learn how to: display just the edges that lie on the work plane (work plane emphasis). display a grid of small dots on the work plane.

The Work Plane Opening the Part

You can work with the part that you were using in the last section of this lesson. If you do, you can skip the step immediately below.

Open

part file uge_work_plane.prt from the uge subdirectory.

This is the same part you were working with in the previous lesson. The only difference is that the WCS is displayed in this part file (at the front bottom corner of the part).

182

Change to Visible Hidden Edges. All edges are displayed in the green color of the part.

The Work Plane Emphasizing the Work Plane Choose Preferences

Work Plane.

The Work Plane Preferences dialog is displayed.

Choose the Display tab.

183

In this case you want only those edges that are on the work plane to be in their normal colors. You want all of the edges that are NOT on the work plane to be dimmed out. Choose the Dim and Selectable option in the Objects Off Work Plane section of the dialog.

OK this change. All of the edges not on the work plane are dimmed (displayed with a gray color).

Use the dynamic WCS to move the WCS upward to the top front left end point on the part. Now only those edges on the XC-YC plane are displayed in the green color All of the others edges are dimmed. In a complex part, this could help you visually separate edges. Because of the option you chose, however, you could still select any edge. (The other option would restrict you to selecting just the control points of those edges on the work plane.)

The Work Plane Resetting the Dialog Use Preferences

Work Plane to display the Work Plane Preferences dialog again.

Choose the Display tab.

184 Choose the Normal Display option.

Apply this change.

The Work Plane Choosing a Grid Choose the Grid tab.

Every once in a while it would be handy for your model creation activities to be able to display a grid on the XC-YC plane. You would use this dialog to set up the spacing for the grid. The default values will create: a rectangular grid a grid displayed in a light blue color. a grid with 6 mm spacing. Be sure that the Show Grid icon is on (depressed).

Apply the dialog. The grid is displayed on the XC-YC plane.

185

The Work Plane Turning the Grid Off If you rotated the WCS, the grid would rotate with it.

Rotate Restore

the part in any direction. the view.

Choose the same icon (now called Hide Grid).

OK the dialog. The grid disappears.

The Work Plane Closing the Part Close the part file, then go on to the next lesson.

186

Organizing Parts There are many different ways you can organize your part file to assist your design work:

In this lesson, you will learn; how you can assign Unigraphics NX objects to different layers. various ways you can manipulate layers. how to move objects from one layer to another. how you can create a unique category for one or more layers. how you can set the color, line font, and line width for new objects. how you can change the color of existing objects.

Working With Layers Layers can be thought of as "transparent overlays" with objects created on different overlays. The ability to place objects on different layers gives you a great deal of control especially if you are working with a complex model. Any object on a layer is three-dimensional. Also objects on different layers can be completely associated with each other. For example, all the objects of the part may be placed on one layer or distributed among many different layers. Your choice will depend on your company standards and the design intent for the part. In this lesson, you will learn: about the purpose of company standards

187 how objects of a part may be distributed onto different layers and why you should use layers. how to determine what objects are on a particular layer. methods of proper layer usage. how to make objects on a particular layer selectable or invisible. how to change the work layer.

Working With Layers Opening the Part File Open

part file uge_layer_1.prt from the uge subdirectory.

This solid model is a plastic molded part with a slotted cover.

The part is a hollowed but has material around the connecting bolt holes. Rotate this part around to see how it is shaped (especially the way the holes are drilled).

It will be a good part to use for this lesson because many different features were used to construct it, and they are distributed across various layers.

188

Restore the view.

Working With Layers Checking the Features Before you continue, you can quickly check the features used to create this part. Use MB3 to undock the Model Navigator icon from the resource bar, then move it to a good location. Resize it if you need to.

NOTE to Unix users: Just select the correct icon on the side of the graphics window.

You can see that many different types of features were used to create this model.

189 Dismiss the Model Navigator by clicking on its Close icon.

Working With Layers Company Standards One very important idea is the idea of "company standards." As you might guess, standards are very helpful when you are looking into a part file that someone else has created. In fact, many companies set up a part file (often called a "seed part") with all of their standards in place—color, layers, units of measure, and so on. Here is an example of layer standards that some companies use: Layers 1-20 Solid geometry Layers 21-40 Sketch geometry Layers 41-60 Curve geometry Layers 61-80 Reference geometry Layers 81-100 Sheet bodies Layers 101-120 Drafting objects Layers 121-150 (open or company specific) Layers 151-180 Manufacturing Layers 181-256 (open or company specific) If a part you are working with has been created following this particular company standard, you would expect to find the solid on layer 1, a sketch on layer 21, reference geometry (datum planes) on layer 61, and so on.

Working With Layers Starting the Modeling Application Up to now you have been working in the Gateway application. That application would let you do some layer work. To be able to work with more layer procedures, however, you will need to be in a different application.

Choose the Modeling icon Application Modeling).

from the Application toolbar (or you can choose

The Unigraphics NXwindow confirms that you are now working in the Modeling application.

190

Working With Layers Displaying Icons on the Utility Toolbar You won't need to work with any of the new modeling oriented toolbars but you will need to add some icons to the Utility toolbar. Right now the Utility toolbar should be docked at the bottom left corner of the Unigraphics NXwindow.

For the activities in this part of the lesson you will need to be able to select these icons on the Utility toolbar. 1. 2. 3. 4.

Layer Settings Layer Visible in View Layer Category Move to Layer

Use MB3 to display the Customize dialog, then choose the Commands tab. In the Toolbars list box, choose Utility. In the Commands section, turn on the first five icons.

191

Working With Layers Displaying the Layer Settings Dialog The Layer Settings dialog will let you manipulate the way you want to use the different layers.

Choose the Layer Settings icon Format Layer Settings).

from the Utility toolbar (or you can choose

The Layer Settings toolbar is displayed.

As you create objects, each one is assigned to the current work layer. The Work text field at the top of the dialog shows that the current work layer is Layer 1.

The number of the work layer is also shown on the Utility toolbar.

Working With Layers Layers with Objects The default setting for the dialog is Layers with Objects.

With this setting on, the dialog will display the numbers of only those layers that have objects on them. In this part file, only the numbers of layers that have objects on them are displayed in the Layer/Status list box.

192

Working With Layers Displaying the Object Count on Each Layer Sometimes it is helpful to know how many objects are on a layer. Choose the Show Object Count option to turn it on.

Now the dialog displays the number of objects on each layer.

A little later you will look at these objects in more detail. Turn the Show Object Count option off.

Working With Layers Displaying the Categories Assigned to Layers You'll notice that the top part of the dialog displays a list of categories.

193

In this part file, five categories have been established. The ALL category lets you choose every layer in the model (256 altogether). You'll notice that the DATUMS category has had a description added to it. Choose SOLIDS from the Category list box.

The system highlights all of the layers assigned to this category. If you scrolled down the highlighted list, you would see that this category ends with layer 20.

Working With Layers Displaying the Category Assigned to Each Layer With Objects Just to check to see that the designer of the part followed the company standards, you can display the category for each layer with objects on it. Choose the Show Category Names option to turn it on.

You can see from the categories assigned to layers in this part file that the designer has indeed followed the standards described earlier.

194

Turn Show Category Names off.

Working With Layers Displaying the Objects on Every Layer It's time to look in more detail at the objects used to create this part. You can do this by making every layer selectable. Choose ALL in the Category list box at the top of the dialog.

The system highlights every category from 1 through 256 (so the list box shows white numbers on a dark background). Toward the bottom of the dialog are four buttons that let you define what you want to do with a highlighted layer.

Choose the Selectable option. Every layer is now designated as "selectable".

195

Apply the dialog. Every object in this part file is now displayed in the graphics window.

Working With Layers Making Only the Work Layer Selectable With every feature shown, the part looks a little complex. But you can simplify the display by making only certain layers selectable.

First, change to Gray Thin Hidden Edges. Choose ALL again, choose Invisible, then Apply the change and OK the dialog. Now you see only the edges that define the solid.

196

Working With Layers Regenerating the Work Because of the complexity of this part, the system is now displaying too many edges in the gray color. But you can regenerate this image. Choose View

Operation

Regenerate Work.

Now the part is displayed correctly.

Working With Layers Selecting Contiguous Layers (With Click and Drag) Perhaps you will like to display all of the sketches that were used.

Use the Layer Settings icon

to display the Layer Settings dialog again.

Place the cursor over the first sketch layer, 21. Press (and hold) MB1; then drag the cursor down until layers 21 through 24 are highlighted.

Choose the Selectable option. Apply this change.

197 The various sketches appear within the solid.

Working With Layers Selecting Contiguous Layers (With Shift-Select) Another way to select contiguous layers is to use a selection procedure called "shift-select". Highlight layer 21. Hold down the Shift key, place the cursor on layer 24, then click MB1. All layers between the two cursor locations are highlighted.

Choose Invisible. Apply this change. Now only the solid is shown.

Working With Layers Selecting Non-Contiguous Layers (With Ctrl-Select) Perhaps you would like to see the datum geometry associated with the first sketch. You know that the sketch is on layer 21 and its associated reference geometry is on layer 61.

198 Choose layer 21 (so that it highlights). Press (and hold) the Control (Ctrl) key, then choose layer 61.

In this case you just want to have it visible but not selectable. Choose the Visible Only option. Apply this change. The sketch geometry and the datum geometry are displayed: The sketch geometry consists of the blue lines under the part. The datum geometry consists of the green square and arrows at the front left corner of the part.

Working With Layers Determining the Layer of an Object Suppose you wanted to find which layer the datum plane was on. In the graphics window, select the edge of the datum plane. (Be sure it highlights white.)

199

The object's associated layer is highlighted in the Layer Settings dialog.

Another way to find an object's associated layer is to use the Model Navigator.

Working With Layers Displaying All Layers in the List Box Sometimes you will want to see all layers, not just those with objects on them. Set the Layers option to All Layers.

Now the number of every layer is displayed in the list box. Before you continue, you can make all layers invisible. In the Category list box, choose ALL. Choose Invisible. Apply this change.

Working With Layers Making a Layer Selectable (Using MB1)

200

If you just want to look at objects on one layer, you can use MB1 to quickly change the status of a layer. For example, you might want to see how the Trim Body feature that is on layer 41 was used to create the curved top of the part. First, change back to displaying only those layers with objects on them.

Double-click on layer 41. With this action the system changes the layer to Selectable.

Apply this change. Now you can see the feature that was used to create the curved top face of this part.

Working With Layers Making a Layer Invisible (Using MB1) You can also use this same technique to change a Selectable layer to Invisible. For example, you might want to see how the other Trim Body feature (on layer 42) was used to create the slots in the curved top face of the part. Double-click on layer 42 to change it to Selectable.

201

Double-click on layer 41 to change it to Invisible (shown by having NO name next to the number).

Apply this change. Layer 41 is made invisible, layer 42 visible and selectable. Now you can see the feature that was used to create the slots in the curved top face of this part.

Working With Layers Changing the Work Layer (Using the List Box) Suppose this solid requires rework. Since the feature is selectable, you could make changes. However, if you wanted to make the solid invisible, you would need to make the work layer (layer 1) invisible. Since the work layer is ALWAYS visible and selectable, you will need to make layer 41 the work layer, then change the status of layer 1. Click on layer 42 to highlight it.

Choose Make Work.

202 The work layer was reassigned to layer 42. At the same time it changed the former work layer into a selectable layer.

Double-click on layer 1 to change it to Invisible. Apply this change. Now only the Trim Body feature is visible.

Working With Layers Changing the Work Layer (Using the Work Field) You can quickly change work layers when the Layer Settings dialog is up. In the Work field at the top of the dialog, key in 1, then press Enter.

The work layer was reassigned to layer 1 and at the same time, the previous work layer (layer 42) was give a selectable status.

203

Apply this change.

Working With Layers Changing the Work Layer (Using the Utility Toolbar) Here is another way to quickly change the work layer. Use the procedure below to change the work layer back to layer 42. Drag the Layer Settings dialog up so the Utility toolbar is visible. In the Utility toolbar, double-click on the number to highlight it. In the Work Layer field, key in 42, then press Enter.

The change is immediately reflected on the Layer Settings dialog.

Use any method to make layer 1 the work layer again. Make layer 42 invisible. OK the Layer Settings dialog. Close the part file.

Manipulating Layers Layers are useful because they give you control over the distribution of the part entities.

204

In this part of the lesson, you will learn how to: find out how the part was constructed. move objects from one layer to another filter for one type of object. deselect and select objects. select objects with a trap rectangle. change the work layer. make a layer visible in certain views but not others. save a view you have changed. create a category for layers and assign layers to that category.

Manipulating Layers Opening the Part For this section of the lesson you can use a part that is a little less complex than the last part.

Open

part uge_layer_2.prt.

This is a part you've seen before, a control arm.

205 You can see that some datum geometry is displayed.

Manipulating Layers Checking the Toolbars Notice that on the Utility toolbar you don't see the icons you added when you were in the Modeling application. This is because the system retains the changes you made on toolbars in different applications.

Choose the Modeling icon on the Application toolbar (or you can choose Application Modeling). Manipulating Layers Checking the Construction of the Part

You can take a look at the different features that were used to construct this part. When the Model Navigator window is displayed you may need to adjust its size and location. Use MB3

Undock to undock the Model Navigator

Manipulating Layers Features Used to Create This Part The features used in this part include: datum planes. datum axes. four sketches (each with a descriptive name). extrusions (extruded from the sketch profiles). a slot feature. a boss feature. a pad feature. a blend feature. two types of hole features (simple and counterbored).

on the resource bar.

206

Manipulating Layers Setting the Display of the Layers Before you continue you can take a quick look at the layers with objects.

Use the Layer Settings icon dialog.

on the Utility toolbar to display the Layer Settings

All of the layers except the work layer (layer 1) are invisible. In the graphics window you can display all of the objects that are on the invisible layers. Make all of the invisible layers selectable: Use Shift-Select or the drag method to highlight all of the invisible layers (layers 21 through 24). Choose Selectable OK the dialog

207

Now every object used to create this part is displayed in the graphics window

This includes some datum geometry that was originally created on layer 21 when the first sketch was created.

Manipulating Layers Preparing to Move Objects From One Layer to Another Before you begin moving objects, you need to change the display of the part.

Change to Invisible Hidden Edges. Use the Layer Settings dialog to make layer 21 the work layer. — Make all other layers Invisible. Be sure the Layer Settings dialog is displayed. Choose layer 21, then choose Make Work.

Use Shift-Select to choose every layer in the list box.

208 Choose Invisible. OK the dialog.

The work layer is unaffected by the "invisible" instruction.

And now only the objects on layer 21 are selectable: the sketch profile (blue curves) and the datum plane and two datum axes.

Manipulating Layers Moving Objects by Selecting Them One By One If you have just a few objects to select, you can do it this way.

Choose the Move to Layer icon Move to Layer).

on the Utility toolbar (or you can choose Format

The Class Selection dialog is displayed.

This dialog offers you many different ways you can select objects in the graphics window. Select each curve in the sketch (blue lines and arcs) until all are highlighted.

209

Press the Escape key to deselect (unhighlight) everything. This action also closes the dialog.

Manipulating Layers Filtering for a Type of Object If you want to select just one type of object, you can have the system filter for only that type.

Display the Move to Layer dialog. Choose Type. The Select By Type dialog is displayed. It lists all the types you can filter for. Scroll up to the top of the list, then select Sketch.

OK the dialog. Choose Select All. Only the sketch objects highlight.

210

Cancel the dialog.

Manipulating Layers Deselecting Certain Objects Another approach to selecting specific objects is to select everything then deselect the objects you don't want.

Display the Move to Layer dialog. Choose Select All. Every object is highlighted. Since you only want to move the sketch curves, you must deselect the datum objects. Press (and hold) the Shift key. Select the datum plane then each datum axis (so they are unhighlighted).

Cancel the dialog.

Manipulating Layers Selecting Objects With a Trap Rectangle

211 Here's another way to select objects. This method is useful whenever you want to select a specific type of object but you don't want to select all of that type in the part. In this case you want to move only the datum geometry to a layer reserved for this type of object.

Display the Move to Layer dialog. Choose Type. Choose Datums from the object list.

OK the dialog. You can use a trap rectangle to select everything in the graphics window. Place the cursor at this location.

Press (and hold) MB1, drag the cursor downward diagonally until every object is within the trap rectangle, then release MB1.

212 Only the datum geometry is highlighted.

Manipulating Layers Choosing the Destination Layer Now that you have selected the objects to move, you are ready to define the destination layer. First you must tell the system you are finished selecting objects. OK the Class Selection dialog. The Layer Move dialog is displayed.

The Category list box displays all of the names of layer categories that have been created in this part file. The Layer list box displays all the layers containing objects.

You want to reassign the selected datum geometry to the first layer reserved for datums (layer 61). In the Destination field, key in 61.

OK the dialog. Nothing seems to happen in the graphics window, but if you looked at the Layer Settings dialog you would see that layer 61 now had objects on it and the system has automatically made it selectable. (It does this so the objects will remain visible in the graphics window).

213

Manipulating Layers Changing the Work Layer (Using the Utility Toolbar) Before you continue, you need to return the work layer to layer 1. You could key in the number of the layer you want, but there is another way to do this. Click the drop-down symbol next to the Work Layer option box on the Utility toolbar. The numbers of all the layers with objects on them are displayed in the "drop-down" menu (only it drops up because there is no room at the bottom of the window).

Choose layer 1.

Manipulating Layers Moving Only the Datum Axes to Another Layer To maintain company standards, you would like to move the datum axes to their own layer. So in this case you can further refine the type of object you want to select.

Display the Move to Layer dialog. Choose Type.

214 Choose Datums.

Choose Detail Filtering (at the bottom of the dialog). You only want to select datum planes. (If there are any datum axes, you would like to have them on a different layer than the datum planes.) On the Datum Filter dialog, choose Datum Axis.

OK the dialog. OK the Select By Type dialog. On the Class Selection dialog, choose Select All. Only datum axes are highlighted. (The Status Line tells you that 2 objects have been selected.) OK the Class Selection dialog. The Layer Move dialog is displayed.

Manipulating Layers Choosing the Layer to Move To You want to move the datum axes to a layer reserved for datum geometry, in this case layer 62. In the Destination Layer field, key in 62, then press Enter. If you looked at the Layer Settings dialog, you would see that layer 62 now has objects on it and has been made selectable.

215

Manipulating Layers Moving All the Other Datum Geometry You can move the remaining datum geometry to an appropriate layer. But you don't want to select and move the datum geometry on layers 61 and 62.

Use the Layer Settings dialog course).

to make every layer invisible (except the work layer, of

Only the datum geometry on layer 1 is still visible.

Use the Move to Layer icon to layer 65.

to select only the remaining datum geometry and move it

Now only the solid on layer 1 is visible.

216

Manipulating Layers Preparing to Make a Layer Visible in a Specific View You may want to display objects in a specific view, but they are assigned to a layer with invisible status. Before you do this, you must set up the views. Use the MB3 pop-up menu to replace the view with the isometric view.

Display the view with Invisible Hidden Edges

if you need to.

Manipulating Layers Making a Layer Visible in a Specific View In this case you would like to see all of the sketch curves displayed in the isometric view but only in this view.

Choose the Layer Visible in View icon Format Visible In View).

from the Utility toolbar (or you can choose

The Visible Layers in View dialog is displayed. (This is the first version of this dialog). Since you have only one view displayed, only one view name is shown in the list box (and it is highlighted).

217

OK the dialog (with MB2) to select the highlighted view name. The second Visible Layers in View dialog is displayed. It gives you a list of the status of every layer in the part file. In this case all layers (except the work layer) are blank, which means they are all invisible.

You want to have all of the layers with sketch geometry displayed in this view. To do this you could scroll down and select those layers. But there is another way to do it. Since you don't care how many layers reserved for sketches are displayed, you can use the sketch category at the top of the dialog. In the Category list box, choose SKETCH_GEOMETRY.

All layers assigned to this category (layers 21 through 40) are highlighted. Choose Visible. The Layer Status list box shows you which layers will be visible in the isometric view.

OK the dialog. Now the sketch curves are displayed.

218

Manipulating Layers Saving a Changed View Now that you have made a change to this view, you must save it if you want to preserve the change. First you can make the relationships between sketch profiles and the edges of the solid a little more clear.

Change to Gray Thin Hidden Edges. Choose View

Operation

Save (be sure you don't select "Save As").

That preserves your changes. Now you can test your work. Use the MB3 pop-up menu to Replace the view with the trimetric view.

No sketch curves are displayed in this view. Replace the view with the isometric (TFR-ISO) view. The sketch curves are displayed only in this view.

219

Manipulating Layers Assigning Layers to a Category At some time you might have to create a new category then assign specific layers to it. Let's say you need to reserve some layers for a category called "Mechanism".

Choose the Layer Category icon. The Layer Category dialog is displayed. The top list box displays all of the existing categories in the part file. (Remember, the ALL category is supplied by the system.) In the Category field, key in mechanism (lower case letters are OK, but no spaces).

Would you like to add a description to this category? In the Description field, key in Mechanism Tools (use upper and lower case here, and spaces are OK).

Manipulating Layers Choosing the Layers That sets up the category and its description. Now you must choose those layers that are to be assigned to this new category. In this case layers 121 through 125 must be reserved for the "MECHANISM" category. Choose Create/Edit. Now the dialog displays all of the layer numbers. You can assign any layer you want to this new category, even layers that have been used in other categories.

220 Scroll down, then select layers 121 through 125 (use Shift-Select).

Choose Add. The system confirms your selections.

OK the dialog. The system has added your new category to the others (in alphabetical order). The next time you display the Layer Settings dialog, you will see the new category in the list box.

Manipulating Layers Closing the Part File Close the part file.

221

Displaying Parts There are many different ways to affect the display of parts. In this lesson you will see just a few of the possibilities.

In this lesson, you will learn; how to blank parts of an object. how to set the color, line font, and line width for new objects. how to change the color of existing objects.

Blanking Objects Sometimes it is difficult to select specific objects in a complex part. Or you may not want a feature to be displayed. In these cases you can "blank" objects (that is, make them invisible in the graphics window). For example, you could blank the datum planes rather than using the Layer Settings dialog to make them invisible.

222

In this part of the lesson, you will learn how to: blank selected objects in the graphics window. unblank selected blanked objects. unblank all blanked objects.

Blanking Objects Opening the Part File One way to do this is to use the Feature Browser dialog. (You used this dialog in the lesson on "selecting features".)

Open

part file uge_blank.prt.

This is a fitting with various holes in its flange and sides. You will recognize that three datum planes are displayed in this trimetric view. The part is displayed with gray thin hidden edges so you can see the edges of the holes and grooves within the part.

223 The developer used these datum planes to position the holes in the part. You will need to be in the Modeling application for this work.

Choose the Modeling icon

from the Application toolbar.

Blanking Objects Setting Up the Utility Toolbar In this part of the lesson you will need to use several icons on the Utility toolbar that are not yet displayed. Use the Customize dialog to display these icons on the toolbar. With the cursor in the toolbar area, click MB3. If you need to, turn on the Utility option to display the Utility toolbar. Choose the Customize option (at the bottom of the pop-up menu). On the Customize dialog, choose the Commands tab. In the Toolbars list box, choose Utility. In the Commands area, scroll down to the bottom of the list, then turn on these icons: — Blank — Reverse Blank All — Unblank Selected — Unblank All of Part

Close the Customize dialog.

Blanking Objects Blanking Objects (Using the Action-Object Method) Say that you need to blank the two datum planes that run through the part from left to right. There are two methods you can use: Object-Action or Action-Object

224 Here's an example of the "action-object" method. First you select the icon (action) then the object you want to affect.

Choose the Blank icon from the Utility toolbar (or you can choose Edit Blank) to display the Class Selection dialog.

Blank

(You can also use the accelerator Ctrl+B to do this.) Select the edge of this datum plane.

OK the Class Selection dialog (use MB2). The selected datum plane disappears.

Blanking Objects Blanking Objects (Using the Object-Action Method) Here's an example of the "object-action" method. In this selection method you first select the object you want to do some action to, then you perform the action by selecting an option or icon. Select the edge of this datum plane.

225

You could select more objects if you needed to.

Choose the Blank icon

from the Utility toolbar.

The selected datum plane disappears.

Did you notice that the Class Selection dialog did not display with this method?

Blanking Objects Reverse Blanking Blanked Objects

If you need to check to see exactly which objects you have blanked, you can do this.

Choose the Reverse Blank All icon Edit Blank Reverse Blank All).

from the Utility toolbar (or you can choose

(You can also use the accelerator Ctrl+Shift+B to do this.) Now the only objects shown in the graphics window are the two blanked objects.

226

You can repeat this procedure to return to the previous display.

Choose the Reverse Blank All icon. Now you are back to where you were with only the datum planes blanked from the part. Blanking Objects Unblanking Selected Objects

If you need to, you can unblank any blanked object. Let's say you need to have just one of the blanked datum planes back (the one that goes through the axis of the vertical cylindrical face).

Choose the Unblank Selected icon Selected).

(or you can choose Edit

Blank

(You can also use the accelerator Ctrl+Shift+K to do this.) The Class Selection dialog is displayed.

In the graphics window the system shows you all of the blanked objects. Select the datum plane that's behind the front one.

Unblank

227

OK the Class Selection dialog. This blanked object you selected is unblanked.

Blanking Objects Unblanking All Blanked Objects This is the icon you'll use most after you've blanked some objects. Generally when you are finished you will want to "clean up" the model by displaying all blanked objects.

Choose the Unblank All of Part icon All of Part).

(or you can choose Edit

(You can also use the accelerator Ctrl+Shift+U to do this.) Every blanked object is immediately displayed again.

Blank

Unblank

228

Blanking Objects Closing the Part File Close the part file, then go on to the next section.

The Appearance of Objects The color of a new object is determined by a preferences dialog. If you don't want to use the default object color, you can choose another. There are also several different ways you can display an object. In this part of the lesson, you will learn: how to choose the color preference for a new part. how to change the color of an existing object. how to display an object with perspective. how to make an object translucent.

The Appearance of Objects Opening the Part File Open

part file uge_objects.prt.

This is the fitting that you have worked with before.

229

When an object is created, its color, line font, and width are determined by the settings in a preferences dialog.

The Appearance of Objects Displaying Icons You Will Need In this part of the lesson you will need to use the Edit Object Display icon that's on the Utility toolbar. (It may already be there from a previous lesson.)

If you need to, use the Customize dialog to first display the list of icons for the Utility toolbar. Then scroll down then turn on the Edit Object Display icon.

You will also need to use an icon on the Standard toolbar that may not be displayed. Use the Customize dialog to display the Properties icon on the Standard toolbar.

230 Be sure the Information icon is displayed on the Standard toolbar.

The Appearance of Objects Displaying Information About the Solid

You can find out quite a bit about objects in a part file. Choose Information

Object.

(You can also use Ctrl+I to do this.) The Class Selection dialog is displayed. In this case you only want to display information about the solid. So you will want to filter your selection (so you don't include edges, datum planes and so on in your search). Choose Type. On the Select By Type dialog, choose Solid Body.

OK the dialog. Choose Select All. The solid is highlighted. OK the dialog. The Information window appears. It includes a great deal of information about the solid. The current location (path name) of the part the layer the part is on (layer 1) the color of the part, green (color number 2) its font, width, when it was modified, created, and so on.

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The Appearance of Objects Dismissing the Information Window There are several ways you can dismiss the information window.

NOTE to Unix users: Your menus will display all of the options. You can choose File

Exit on the Information window.

Or you can choose the Close icon at the top right corner of the Information window.

Or you can choose the Information icon on the Standard toolbar.

Use any one of the three ways to close the Information window.

The Appearance of Objects Making a Part Translucent You can alter the translucency of a solid in order to see internal parts and features, even while the body is shaded. (It's similar to a phantom view.) Follow the two step process below: First turn Translucency ON in the global preferences. Then specify the amount of translucency of the part(s).

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The Appearance of Objects Specifying that a Part May Be Translucent This step is not absolutely necessary because the system would ask if you wanted the translucency option turned on. But you need to know where this option is located.

Choose the Visualization Preferences icon. Choose the Visual tab. Turn on the Translucency option (down at the bottom of the dialog).

OK the dialog (use MB2).

The Appearance of Objects Choosing the Amount of Translucency for the Part Now you are ready to experiment with different levels of translucency to see what might be best to display the holes and grooves in the part.

Choose the Edit Object Display icon Edit Object Display).

on the Utility toolbar (or you can choose

The Class Selection dialog is displayed.

Select the solid in the graphics window. OK the Class Selection dialog. The Edit Object Display dialog is displayed.

Watch the part as you slowly slide the Translucency slider to a value of 50 or so.

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Experiment with the Translucency slider until you find a good pictorial balance that shows the internal objects but still gives the part a feeling of solidity. Then leave it set there.

The Appearance of Objects Turning Translucency Off If you were satisfied with the translucency level of the part, you could turn Translucency OFF in the global preferences. When the Translucency option is turned ON later, the level will be set to the current value.

Display the Visualization Preferences dialog. Be sure the Visual pane is displayed. Turn the Translucency option off.

OK the dialog (use MB2). The part appears solid again even though the Translucency slider remains where it was set.

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The Appearance of Objects Closing the Part File Close the part.

Dynamic Sectioning You can section any part dynamically to see its internal objects.

This can be a useful tool when viewing large parts. In this part of the lesson, you will learn how to dynamically section a part (vertically and horizontally).

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Dynamic Sectioning Opening an Assembly Although dynamic sectioning may be used with any part, it is a tool most often used with an assembly (a collection of parts).

Open

part file uge_assy_plate.prt.

This model is an assembly of five different types of parts: bolts (4), spacers (4), nuts (4), bushings (8), and plates (2).

236 Before you continue, take a look to see how this part would look displayed with perspective.

Dynamic Sectioning Displaying Icons You Will need There is an icon that you will need to use in this section of the lesson. Use the Customize dialog to display the Section icon on the Visualization toolbar.

Dynamic Sectioning Sectioning a Part Dynamically Choose the Section icon Operation Section).

from the Visualization toolbar (or you can choose View

The View Sectioning dialog is displayed.

At the same time, two planes appear above and below the part along with the sectioning manipulation tool (which looks like the dynamic WCS). The top plane is shaded. The origin of the tool sits on the top plane.

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Dynamic Sectioning Expanding the Dialog On the View Sectioning dialog, choose More Options.

Now you can see that only the primary (top) sectioning plane is turned on (and appears shaded) while both sectioning planes are visible.

Dynamic Sectioning Sliding the Section Plane Through the Part The slider on the dialog will let you slide the sectioning plane downward (along the negative Z axis of the sectioning tool). But you can also use the tool to do the same thing. Place the cursor over the double cone head of the Z axis of the slider manipulation tool. The head highlights, the cursor turns into the "Dragable" cursor, and you'll see the "Parallel Move" symbol near it.

Press (and hold) MB1, then watch the results as you slowly slide the sectioning plane downward through the part.

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Use the slide to return the primary sectioning plane to its 100% location above the part.

Dynamic Sectioning Capping the Dynamic Section A cap is an area of solid color drawn onto the cutting surface of the section, creating a dynamic "pseudo" face that fills as you move the section clipping planes. You may find this helpful in more complex parts. Choose Show Cap.

You'll notice that you could change the color of the cap if you wanted to. Slowly move the sectioning plane downward again. This time a magenta "cap" is displayed on parts to show their solidity.

239 Move the sectioning plane back up to its location above the part.

Dynamic Sectioning Sectioning at a Different Angle

You could tilt the sectioning planes if you wanted to section through the part at an angle. There are several ways you can do this: You can manipulate the sectioning tool (much as you would rotate the dynamic WCS). Or you can key in an angle value. Let's say you wanted to tilt the sectioning plane vertically to the part. To do this you can rotate the sectioning tool about its Y axis. Place the cursor over this handle on the tool so that the ball highlights and the Rotation symbol appears next to it.

Rotate the sectioning tool to tip both sectioning planes around the Y axis. You'll notice that this action activated the Angle field on the dialog. Another way to tilt the sectioning plane is to key in an angle. In the Angle field, key in negative 90, then press Enter.

The sectioning planes tip vertically to the part. Use the Z axis to move the primary sectioning plane slowly through the part from left to right.

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Cancel the dialog. Dynamic Sectioning Closing the Part File Close the part.

Colors of Objects

You may control the display color of any object.

In this section of the lesson, you will learn how to: choose a color for newly created objects. change the color of an existing object. find the dialog used to choose a different selection color.

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Colors of Objects Opening the Part File You could use any part to demonstrate these procedures.

Open

part file uge_color.prt.

This is a small fitting with various types of holes in its flange.

Colors of Objects Choosing the Color for New Objects Choose Preferences

Object.

(You can also do this with Ctrl+Shift+J.) The Object Preferences dialog is displayed.

When an object is created, its color, line font, and width are determined by the settings on this dialog (which, in turn, are determined by the customer defaults). You can use this dialog to define the color, line font, and width that you would like to use for new objects. Display the Type options. A list of entity types is displayed.

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OK the dialog.

Colors of Objects The Selection Color The selection color (also called "system color") in Unigraphics NX has many uses: selected (highlighted) objects view names borders around the views other objects you have not yet seen (like temporary display entities, text, coneheads, and so on) The Selection color option is found on the Color Settings pane of the Visualization Preferences dialog.

Colors of Objects Editing the Color of an Existing Object You saw how you can use the Object Preferences dialog to set up the color preference for objects that you are going to create. But you can also change the display of an existing object by editing it.

Choose the Edit Object Display icon.

243 The Class Selection dialog is displayed.

For this task, you will be changing the color of the solid from green to yellow. Select the part in the graphics window. It turns white (the selection color designated for this part file).

OK the class selection dialog. The Edit Object Display dialog is displayed.

The color of this object is green. If you didn't know the exact color you need, you can select it from an object in the graphics window. (You would choose the Inherit option, then select the object that had the correct color.) Choose the Color option.

You get the small Color dialog.

Select the Yellow icon.

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The Edit Object Display dialog confirms your color choice.

OK the Edit Object Display dialog. The part is now displayed with a yellow color.

Colors of Objects Closing the Part File Close the part.

Part Attributes and Object Attributes You can add a great deal of information to any part file to help in the manufacturing process. In this part of the lesson, you will: add a part attribute to a part. learn about object attributes.

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Part Attributes and Object Attributes Opening the Part File Open

part file uge_objects.prt.

This is the fitting that you were working with in other lessons.

As you saw earlier, when an object is created, its color is determined by the settings in a preferences dialog (and the user default file).

Part Attributes and Object Attributes How Could You Use Part Attributes? One common use of part attributes are parts in an assembly (such as a motor or brake system). When building a bill of materials for the assembly, each part attribute could be listed. At the component level, you can add part attributes such as the name of the person who modeled the part, the engineer who designed the part, the engineer who bought off the part, the date it was created, or any other important information relating to the part.

Part Attributes and Object Attributes Adding a Part Attribute to the Part Suppose you wanted to add a description to the material being used for the part. Every part attribute consists of two components—a title and a value.

246 the title must be one group of characters (with no spaces) the value is a string variable so you can type anything you want (upper and lower case, alpha and numeric, spaces, and so on). You would use a part attribute to record any important information about the part. Choose File

Properties.

The Displayed Part Properties dialog is displayed.

Choose the Attributes tab. You see columns for two part attributes, but there are actually three: title, value, and type.

Add a "type of material" attribute to this part: In the Title field, key in material (use lower case letters). In the Value field, key in 4140 Steel (this string will appear just as you type it).

Press Enter (or you can choose Apply). The title and value of this attribute appear in the list box. Notice that the system automatically changes the title characters to upper case. If you stretched the dialog to the right, you would see that the system has also designated the type as a "string".

Now anyone displaying this dialog could view the added information. Cancel the dialog.

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Part Attributes and Object Attributes How Could You Use Object Attributes? Object attributes look very much like part attributes, but have more flexibility. Any time you need to include information about a specific object on a part, you can use an object attribute. You can place specific data regarding the fabrication of the part (such as fabrication information, manufacturing data, or inspection processes) on any object in the model. You have already specified a "type of material" attribute in the current part. But you might also need to include information about processes to be used on specific areas of the part. Perhaps a specific face requires a special process such as painting or plating, or certain edges of the part require deburring. You can also manipulate attributes by deleting, copying, and listing assigned data types.

Part Attributes and Object Attributes How Could You Use Object Names? You can name anything in a model. You could use object names to organize the part file or for quick referencing. For example, if a part contained object names and you wanted to select certain faces on the part, you could simply key in the name. All faces assigned that name would be automatically selected. Object names are advantageous for quick reference when using functions such as delete, blank, layers, etc. Object names may be selected from the list or directly from the graphics screen (if the name is displayed).

Part Attributes and Object Attributes Closing the Part Close the part file, then continue on to the next lesson.

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Using Online Documentation There are various ways to find the documentation you need.

In this lesson, you will learn how to use: on context help. help found in the documentation. search techniques that will let you find the specific help you might be looking for.

Help On Context When a dialog is displayed, you can display help related to the dialog options. In this section of the lesson you will: display the help for a particular dialog. use the index. search for a specific topic.

Help On Context Opening a Part For this exercise you could actually use any part.

Open

part file uge_doc.prt from the uge subdirectory.

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Help On Context Icons You Will Need There are two icons available on the Standard toolbar that will be useful. On the Standard toolbar, be sure that these two icons are displayed: 1. On Context Help 2. Documentation

You will also need the Layer Settings icon on the Utility toolbar.

Help On Context Adjusting the Help Window When the help window comes up, you will probably need to resize it and move it to a location where you can still read these CAST instructions.

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If you do not have the online help installed, you will get this error message.

If this happens, you will need to talk with your system administrator.

Help On Context Displaying On Context Help About the Layer Settings Dialog Just to see how On Context Help works, you can display help about a dialog you've used before, the Layer Settings dialog.

Choose the Layer Settings icon

from the Utility toolbar.

When you ask for "on context help," the system will look at whatever dialog you have up, then select the appropriate help page from the documentation.

Choose the On Context Help icon

on the Standard toolbar.

The Unigraphics NX Help window is displayed. You can also use Help

On Context or just press function key F1.

251 If you are using Windows, you will need to be able to select the Help window after you change a CAST page.

Help On Context The Layout of the Documentation Window The right hand side of the window displays the information about the dialog that is currently displayed.

The left side of the window displays the various types of search methods that are available. Right now, because the Contents pane is displayed, you see the "contents tree" for Format (because the Layer Settings information is in the Format "book"). The page that is displayed, Overview, is highlighted.

NOTE to Unix users: The Favorites tab is not available on Unix. Close the Help window.

Cancel the Layer Settings dialog. Don't close this part if you are continuing on in the lesson.

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Using the Documentation This section will show you how to search the documentation for specific subjects. In this section of the lesson you will: display the complete documentation. use the index to look for specific information. use the search field to look for specific information. sort the list created by a search. review the icons on the documentation toolbar.

Using the Documentation Displaying the Documentation The difference here from On Context Help is that you start from the top when you call up the documentation. You should be working in part file uge_doc.prt. Remember, when the help window comes up, you may need to resize it and move it to a location where you can still read these CAST instructions. Choose the Documentation icon You can also use Help

from the Standard toolbar.

Documentation on the main menu.

The Help window comes up. It is like the one you saw earlier except now you see a complete list of the contents in the left column.

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Using the Documentation Using the Index to Look for Information One way to find the information you need is to use the index. Choose the Index tab at the top of the left hand column. To find the subject you are looking for: You can either scroll through the index listing window until you have reached the topic of choice. Or you can have the system search for a "keyword" in the index. For example, you might want to look for information on "common tools". Click once in the Type in the keyword to find field. Type common but do not press the Enter key yet.

You can see that the word "common" is used in quite a few headings Double-click on the line Common Tools to display the documentation for common tools.

254

Using the Documentation Where Is This Documentation Located? Many times you will want to see exactly where the page that is displayed is located in the documentation tree. Choose the Contents tab. The list box now shows you that this page is the overview page in the Common Tools book.

You can do the same thing using the Locate icon on the Documentation toolbar.

Let's say you wanted to know more about the Class Selection dialog. Click on the plus sign next to the Class Selection Tool book.

The book "opens" and displays its contents.

Using the Documentation Displaying Complete Titles Sometimes some of the longer titles will be cut off if your left window is too narrow. If this happens, you can do this. Find any truncated title, then place your cursor over it.

255 A tooltip appears that displays the complete title.

Using the Documentation Displaying Specific Documentation Pages Perhaps you would like to know more about the Type option on the Class Selection dialog Click on Type. Now the Type page is displayed.

Using the Documentation Searching for a Specific Topic This time you can search all of the documentation for some specific information. Choose the Search tab.

The Search pane looks very much like the Index pane but it operates in a slightly different manner. Make sure the Match similar words option (at the bottom of the Search pane) is turned on.

256

Using the Documentation The Search Method Suppose you want to find information about the view pop-up menu. In the Type in the word(s) to search for field, type in view.

Choose List Topics or just press Enter. While the system is searching the documentation, it gives you the opportunity to stop the search.

If the system cannot find any documentation for the keyword you've used, you will see this message.

If you receive this message, you can OK it then type a new search word.

Using the Documentation Choosing the Name of the Documentation You Want to See When the search is complete, the system lists every page that contains the word you typed in. (It also tells you how many "hits" it found on the selected topic.)

257 Pull the left window larger horizontally so that you can read more of each "Location" description.

NOTE to Unix users: You can not sort a list. Click MB1 in the Location heading to sort all of the listings in alphabetical order according to their locations.

Scroll down the list (about half way) until you see the series of Gateway locations.

Double-click View Popup Menu

The documentation area displays information about your selection.

258 Did you notice that the word "view" is highlighted everywhere the system found it on the page?

Using the Documentation Sorting the List by Title or by Rank You can use the scroll bar or the Page Up and Page Down keys to read the documentation. Also, you can use the Maximize button to fill the screen with the documentation so that it will have a larger display area. Then, when you are finished, you can Minimize it until you need to use it again. You can also sort the list by titles or by ranking. If you clicked MB1 in the Title heading, the system would put all the titles in alphabetical order.

You can also use the same technique to sort by rank if you needed to.

Using the Documentation The Favorites Tab (Only on Windows) You can use Favorites to place document names in a list so that you can quickly return to them later. It acts just like a bookmark. (This tab is only available on Windows.) Choose the Favorites tab. The Favorites pane is displayed. The topic name is displayed in the Current Topic field at the bottom of the dialog.

Choose Add option (at the bottom right of the dialog).

259 Now the topic name appears in the Topics list box.

Since you can select stored topics at any time, it is easy to return to topics you want to look at more than once. this pane and select any topics that you have stored here to go directory to pages You can either double-click on the name of the topic or highlight it; then choose the Display option.

Using the Documentation Removing a Name From the Topic List It's easy to remove any name from the list of topics. Be sure that View Popup Menu is still highlighted in the Topics list box.

Choose the Remove option. The name is removed.

Using the Documentation Documentation Icons

There are several icons that you might find helpful when you are working with documentation.

Back and Forward will let you quickly return to pages you have looked at.

Print will let you print the page you are viewing.

260

EDS PLM Solutions will display a web page about Product Lifecycle Management.

UG Answer will display a web page about our technical support program.

Using the Documentation Exiting Online Help You can exit whenever you are finished looking through the documentation. Windows users choose the "x" at the top right corner of the window. Unix users choose File Exit.

Using the Documentation Closing the Part Close the part, then continue on to the next lesson.

Common Tools You have already seen several of these common dialogs in previous lessons in this course. However additional information on these tools and others will be helpful in preparing you for the modeling course.

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In this lesson, you will learn: how to use some more filtering techniques on the Class Selection dialog. how to use the Point Constructor to create points on a model and in modeling space. what the Vector dialog is used for. how the Transformations dialog and Plane dialog may be used. how spreadsheets may be used to model parts.

The Class Selection Dialog You have seen the Class Selection dialog in many of these lessons. Before you finish this course, you should see a few more ways demonstrating how you can limit (filter) your selections.

In this part of the lesson, you will learn how to use a filter to limit selectable objects by color or layer.

The Class Selection Dialog Opening the Part

262

Open

part file uge_tools_1.prt from the uge subdirectory.

This is the fitting that has holes and grooves. When this part was saved, all layers with objects were visible so you see the datum geometry and the sketch curves (colored yellow) that were used to create the part.

The Class Selection Dialog Displaying the Edit Object Icon on the Utility Dialog In this part of the lesson, you will use the Class Selection dialog. It would be helpful if you had the Edit Object Display icon displayed. If you don't already have it displayed, turn on the Edit Object Display icon on the Utility toolbar.

The Class Selection Dialog Displaying the Class Selection Dialog As you have seen earlier, when you want to change the color of an object the system first gives you the Class Selection dialog so that you can select those objects you want to edit.

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Choose the Edit Object Display icon

(or you can choose Edit

Object Display).

The Class Selection dialog is displayed.

The various filter methods are grouped together (including the option for using a color as a filter and a reset option).

The Class Selection Dialog Filtering by Layer In earlier lessons you filtered by type. But you can also limit your selections to just those objects on specific layers. For example, you might need to select all of the datum objects (which are on layer 61). On the Class Selection dialog, choose Layer. The Select by Layer dialog is displayed. The lower list box displays all layers with objects. Right now they are all highlighted so they would all be selected.

You want to select all the datum geometry on layer 61 but no objects on layers 1 or 41. Choose layer 61 to make it the only selectable layer. OK the dialog (use MB2). Choose Select All. Only the objects on layer 61 (the three datum planes) are highlighted.

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Cancel the dialog.

The Class Selection Dialog Filtering by Color Another way to filter your selection is to define a color. Perhaps you need to select all of the sketch curves (colored yellow in this part file).

Choose the Edit Object Display icon. Choose the Color option (the rainbow colored bar).

Select the Yellow icon on the small Color dialog.

OK the dialog. The Class Selection dialog confirms your color choice.

265 Choose Select All. All of the yellow sketch curves highlight. Cancel the dialog.

The Class Selection Dialog Filtering by Attributes There is a fourth filtering method that you might find useful. If you choose Other on the Class Selection dialog, you will get a list of other types of objects that you can use as a filter: line fonts and widths plus a dialog for user defined attributes.

The Class Selection Dialog Resetting the Dialog You can reset all the filter methods settings at any time by selecting the Reset option.

This will reset all the filter methods back to their defaults. Also, whenever you dismiss the dialog, all settings will be returned to their defaults.

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The Class Selection Dialog Modality Many procedures that you will use in Unigraphics NX are "modal". That is, the system will cycle you to the beginning step of the procedure so you can continue using the procedure. This also means that the current procedure will stay in effect until it is explicitly changed. Most modal parameters on a dialog remain in effect only during the work session—from logon to logoff. When you begin a new work session, the dialogs will appear with their default values.

The Class Selection Dialog Closing the Part Close the part, then continue on to the next section.

Some Selection Methods In this part of the lesson you will be introduced to other selection methods available with the Class Selection dialog.

Some Selection Methods Opening the Part

267

Open

part file uge_tools_2.prt.

This is the part you were just working with. It was saved with a wireframe image with gray thin hidden edges and with all layers selectable.

Some Selection Methods Setting Up the Part In this part of the lesson you will need to be able to select specific lines (yellow curves) from this model. So you will want to make only those curves on layer 41 selectable.

Bring up the Layer Settings dialog.

Here is a technique you could use if you could not remember exactly which layer the curves were on. Choose the yellow phantom line that runs down the axis of the cylinder. Layer 41 highlights on the dialog.

268 Make the highlighted layer the Work layer. Then double-click each of the other layers to make them Invisible.

OK the dialog. Now only yellow curves are visible in the view.

Some Selection Methods Improving the View You will want the curves to fill the graphics window when you fit the view.

Display the Visualization Preferences dialog. Display the Screen pane. Set the Fit Percentage to 90. OK the dialog. Fit the view. You can also make the curves easier to work with by changing to a front view. Use the MB3 pop-up menu to Replace the view with the FRONT view.

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Some Selection Methods Selecting Curves or Edges by Chaining Many times you will want to select contiguous curves or edges. To see how this works, you can use the same edit dialog you used earlier.

Choose the Edit Object Display icon. The Class Selection dialog appears. Choose Chain. (You'll notice that the dialog would now let you cancel the chain procedure.) The cue tells you to select the start of the chain. With this procedure you can select any curve in the profile. Select any line.

270 The cue line now says you can select the end of the chain. Also, the End Chain option has become the default action. Since the profile is made of contiguous lines, you can have the system select all of them. Choose End Chain (use MB2). All the curves in the profile highlight.

Cancel the Class Selection dialog.

Some Selection Methods Partial Chaining of Curves Sometimes you may not want to select every curve in the profile, but still want to use the chain procedure. You would select your curves so that only the ones you wanted would be included in the chain. For example, you might need to select only these curves.

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Choose the Edit Object Display icon. You can define the direction of the selection process by selecting a curve on one side or the other of its midpoint. On the Class Selection dialog, choose Chain. You want to select (chain) in a counterclockwise direction. Select the bottom horizontal line on the right side of its midpoint.

Select the long vertical line on the right (anywhere on the line). Only those curves that are contiguous from your first selection to your second selection highlight. Cancel the Class Selection dialog.

Some Selection Methods Closing the Part File Close the part, then continue on to the next section.

Trap Selection Methods As you just saw, there are several ways that Unigraphics NX will let you select features.

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In this section of the lesson you will learn a few more selection techniques using the trap rectangle and the trap polygon. You will learn how to: use a trap rectangle to select objects. use a trap polygon to select objects.

Trap Selection Methods Opening the Part For this exercise you can work with a belt drive for an automotive supercharger.

Open

part file uge_tools_3.prt.

Rotate the part so that you can see how it is constructed.

If you zoomed in closer to these inner spline teeth, you would see that they do not go all the way through the part.

273

Trap Selection Methods Changing the View To practice selecting objects with a trap rectangle, you will need to display a different view. In this case you will want to look straight down onto the inner spline teeth. Due to the construction methods of this part, the teeth will appear only on the bottom of the part. On the View toolbar, click on the arrow next to the icon of the current view (trimetric).

From the drop-down menu, choose the Bottom view icon.

The view rotates into its bottom view orientation. However, the shading in this view makes it a little difficult to clearly see that the teeth don't go all the way through the part. For your next task it will be better if you displayed the part in a wireframe image.

Change the view to display Invisible Hidden Edges. Now the edges of the teeth are displayed more clearly.

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Trap Selection Methods Using a Trap Rectangle to Select Objects To demonstrate the differences between the rectangular and polygon trap methods, you can select the faces of all the spline teeth and change their color.

Choose the Edit Object Display icon. The Class Selection dialog is displayed. For this part of the exercise, a trap rectangle is used. Notice the Rectangle/Polygon Method option is set to Inside/Crossing.

This means that anything inside or crossing your trap rectangle will be selected. Place the cursor above the part and to its left, press (and hold) MB1, drag the cursor diagonally downward and to the right, then release MB1.

275

Everything inside and outside the trap rectangle are selected. This is not what you want.

Trap Selection Methods Deselecting the Selected Objects If you used Back or Cancel, you would lose the dialog. What you want to do in this case is to deselect the selected objects, then use a different selection method to capture just the faces of these inner teeth. Press (and hold) the Shift key, then select the part.

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Trap Selection Methods Selecting Faces Only Since you want to change the color of just the faces of these inside teeth, you can filter for only faces. In the Filter Methods section of the Class Selection dialog, choose Type. The Select By Type dialog is displayed.

Choose Face.

OK the Select By Type dialog.

Trap Selection Methods Using a Trap Polygon to Select the Faces of the Spline Teeth You want to select only the faces of the spline teeth. The trap polygon method will let you select 11 points instead of 40 separate faces. To avoid selecting too many faces, you can limit your selection to those faces that will be inside the trap polygon. Set the Rectangle/Polygon Method to Inside.

Choose Polygon.

Trap Selection Methods

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Constructing the Trap Polygon You will want to keep the vertices of this trap polygon within the top face of the part, but not miss any spline teeth faces.

Zoom in on the spline teeth. Begin indicating on the top face of this inside tooth construction. You'll notice that the system keeps the trap polygon after each indicate.

Continue indicating around the teeth. When you get to a place where the trap polygon completely surrounds the teeth, click MB2 to choose the End Polygon option.

You can see from the highlighted inner and outer edges that the top face of this inner part was also trapped. Deselect the top face (using Shift+MB1).

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Trap Selection Methods Changing the Color of the Selected Object By Selecting a Color OK the Class Selection dialog. You are ready to assign a different color to the object you selected. On the Edit Object Display dialog, choose the Color option.

On the small Color dialog, choose any one of the Blue icons. The Edit Object display dialog confirms your choice. OK the dialog. You won't be able to see the sides of the spline teeth until you shade this display.

Shade the display. Fit the view. Rotate the view

around until you can see the faces of these spline teeth.

279

Trap Selection Methods Closing the Part File This completes this section of the lesson. Close the part file, then go on to the next section.

The Point Constructor The Point Constructor dialog lets you create or define points either in modeling space or on a part.

280 In this part of the lesson, you will learn how to: create a point by selecting a control point. display information about an object. create a point at an X,Y,Z location. delete an object.

The Point Constructor Opening the Part

Open

part file uge_tools_4.prt.

This is the part you were working with in a previous section of this lesson. Only the sketch curves that are on layer 41 are displayed. Notice the location of the origin of the WCS.

To use the Point Constructor you will need to be in the Modeling application.

Choose the Modeling icon Application Modeling).

on the Application toolbar (or you can choose

The Point Constructor Creating a Point by Selecting the Control Point of a Curve Unigraphics NX does often not require creation of points, but sometimes you need to define specific locations in space or on existing entities. The technique is the same for either task. Choose Insert

Curve

Point.

281 (There is an icon available for this on the Curves toolbar.) The Point Constructor dialog is displayed.

The icons at the top of the dialog represent the methods available for point creation. Run the cursor over the icons to see their names.

Begin by creating a point at the end point of an existing curve. Choose the End Point icon. Select the end point at the end of this vertical line.

The point symbol (a little green plus sign) appears at the end of this curve. This shows that there is now an "existing point" at the location you selected.

Also, the three Base Point text fields give you the location of this new point in modeling space in relation to the current orientation of the WCS (which is at the bottom of the vertical phantom line).

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The Point Constructor Displaying Information about an Object Perhaps you needed to define a point that is a half inch above the end of the phantom line. Before you can create this point, you will need to know the length of the phantom line. Choose Information

Object.

The Class Selection dialog is displayed.

Select the phantom line. OK the Class Selection dialog. The Information window appears. The length of the phantom line is 3.5 inches. Close the Information window.

The Point Constructor Resetting the Base Point Fields In this next exercise you will use the Base Point text fields to create a point in modeling space in relation to the current orientation of the WCS. Since you just used the Point Constructor dialog to create a point, the XC, YC, ZC location of that point is still in the three Base Point fields. Choose Reset to set the three base point fields to zero.

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The Point Constructor Creating a Point by Keying in an XC, YC, ZC Location Now you are ready to create a point in modeling space. The phantom line lies along the current +Z axis. And you now know that it is 3.5 inches long. Choose Existing Point at the top of the dialog. Remember, you need a point a half inch directly above the end of the phantom line. In the ZC field, key in 4, then press Enter.

OK the dialog. Fit

the view.

A point has been created a half inch above the top end of the phantom line.

The Point Constructor Checking the Location of the New Point Check the new point to ensure it was created in the XC-YC plane. Watch the location of the point in relation to the other objects as you use MB2 and cursor placement to rotate the part around the vertical screen axis

284

Use the MB3 pop-up menu to Restore the view.

The Point Constructor Creating a Point by Offsetting it from a Reference Point You can create a point by offsetting it from an existing point. Suppose you want to create a point directly above the vertical line on the left side of the profile and horizontal from the last point you created.

This means that the new point must be 0.8 inch away from the newly created point along the XC axis. The Point Constructor dialog should still be displayed. Leave the position icon set to Inferred.

The Point Constructor Choosing the Offset Method You want to be able to key in an offset distance from your reference point (which will be the point you just created).

285 Display the drop-down menu on the Offset option.

You get the various ways you can define the specific values of the offset. (You can read about each of these methods in the online help.) In this case you want to offset the point along the ZC axis. So you can use the Rectangular offset method. Set the Offset option to Rectangular.

The Point Constructor Defining the Reference Point and Keying in the Offset Values The cue tells you to specify an inferred (reference) point. For the reference point, select the point above the end of the phantom line. An asterisk appears on the control point. Because you are now using the rectangular offset method and have selected a reference point, the system has relabeled the three text fields on the dialog to let you key in delta values for a WCS offset.

The cue tells you to enter the offset in terms of three WCS delta values. In the Delta-XC field, key in a positive .8, then press the Enter key (which OK's the dialog).

286

The offset point appears above the left vertical line of the profile.

You will notice, too, that the Base Point text fields now report the location of the new point in terms of the current location and orientation of the WCS (4 inches directly above its 0,0,0 location).

The Point Constructor Closing the Part File Close the part, then continue on to the next section.

The Vector Constructor The Vector Constructor dialog lets you define a vector in modeling space. A vector has directional components but no magnitude or origin. The Vector Constructor dialog will provide you with many different ways you can define the direction of a vector.

In this part of the lesson, you will: use the Vector Constructor dialog to define the axis of a new cylinder feature.

287 use the Plane dialog to define a plane that can be used to mirror the cylinder.

The Vector Constructor Creating a New Part

For this demonstration, you can start a new part file rather than opening an existing part file.

Choose the New icon

on the Standard toolbar (or you can choose File

New).

You will want this part to be modeled in millimeters.

NOTE to Unix users: Your Units options will be arranged somewhat differently. Turn on the Millimeters option.

For a name, key in vector, then press Enter to OK the dialog and create the part.

You will remember that the system will automatically add the ".prt" extension to your keyed in name.

The Vector Constructor Creating a Cylinder You will want to look at the part you are going to create in an isometric view. Use the MB3 pop-up menu to Replace the view with a TFR-ISO (isometric) view. For this demonstration, you will created a cylinder feature. During the creation you will be asked to define a vector for the axis of the cylinder.

Choose the Modeling icon Application Modeling).

from the Application toolbar (or you can choose

288 One of the procedures for creating a cylindrical solid asks you to define a vector.

Choose the Cylinder icon

(or you can choose Insert

Form Feature

Cylinder).

The Cylinder dialog is displayed.

The cue line prompts you to choose the Cylinder creation method. These methods are described in the Gateway documentation.

Use MB2 to OK the action button, Diameter, Height.

The Vector Constructor is displayed.

The Vector Constructor Using the Vector Constructor You get the Vector Constructor dialog at this point because the system needs to know the direction of the axis of the cylinder in modeling space. It gives you many different methods you can use to define the direction of a vector. Run the cursor over the icons at the top of the dialog to see their names.

289

You want the cylinder axis to be along the ZC axis of the WCS.

Choose the ZC Axis icon

from the dialog.

A vector conehead appears on the WCS to show the direction of the vector. Remember, though, that a vector does not really have an origin.

Use MB2 to OK the dialog. The Cylinder dialog is displayed again, this time with fields for the two values the system needs to create the solid.

290 For this cylinder, you can accept the default values. Use MB2 to OK the dialog. The Point Constructor dialog is displayed.

The Vector Constructor Defining the Origin of the Cylinder The Point Constructor dialog appears at this step in the procedure because the system needs you to define the location of the bottom face of the cylinder. For this solid you can just create it at the origin of the WCS—XC = 0, YC = 0, and ZC = 0. If you need to, Reset all the Base Point fields to zero. OK the dialog (with MB2). Fit

the view.

The cylinder appears in the graphics window with its origin at the origin of the WCS and its axis parallel with the ZC axis.

This is a "modal" procedure. The system assumes you want to create another cylinder, so you are cycled to the first step of the procedure (the Vector Constructor dialog). The DiameterHeight method is still active. Cancel the dialog.

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The Vector Constructor Transformations and Planes Occasionally you will need to specify the location and orientation of a plane in modeling space. For a demonstration of this, you can copy the cylinder by defining a mirror plane across its top end. You will need to edit the existing solid by "transforming" it. Choose Edit

Transform.

The Transform dialog appears. (Actually, it is just like the Class Selection dialog.)

The cue tells you to select the object(s) you want to transform. Select the cylinder anywhere. OK the dialog to end the selection process. The "Transformations" dialog is displayed with all the transforming methods you can use.

Choose the Mirror Through a Plane option. You get the Plane dialog with many different ways you can define a plane.

The Vector Constructor Plane Options For this task you can use a "principal plane" of the WCS to define the mirror plane. (You can learn more about these options in the online help.) Choose Principal Plane.

292 The dialog changes to give you the types of principal planes you can use. Since you built the cylinder parallel to the ZC axis of the WCS, you can define the location and orientation of the mirror plane by keying in a distance along the ZC axis to define a "constant" plane. Choose ZC Constant. You'll remember that you made the cylinder 100 mm high. Key in 100, then press the Enter key.

The plane symbol is displayed on the upper end of the cylinder. Its shape gives you the orientation of the plane (it is a 3-4-5 isosceles triangle).

Also, the Transformations dialog is displayed. You will need to copy the cylinder in order to mirror it. Choose Copy. Fit

the view.

A second cylinder appears over the first. It is an exact mirrored copy of the first. Cancel the dialog.

The Vector Constructor Closing the Part File Close the part, then continue on to the next section.

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Spreadsheets in Unigraphics NX There are several different types of spreadsheets available for more complex parts. One very common use is to set up a spreadsheet with different values for one part so that you can define a "family of parts" using just one solid. You'll see examples of this in the Assembly Modeling course. In this section of the lesson, you will learn: the difference between the Gateway spreadsheet and the Modeling spreadsheet. how a Modeling spreadsheet can be used to modify the model.

Spreadsheets in Unigraphics NX Unigraphics NX Spreadsheets When the spreadsheet is displayed, you may have to adjust its size in order to see the CAST instructions. Also, you will not be able to scroll or change the CAST page as long as the spreadsheet is up.

If you are working in Windows, you will get the Excel spreadsheet. If you are in Unix, you will get the Xess spreadsheet. You won't save any of the spreadsheets you look at.

Spreadsheets in Unigraphics NX Displaying the Gateway Spreadsheet You could use the Gateway spreadsheet to set up any calculations appropriate for spreadsheets.

Open

part file uge_spreadsh.prt.

Choose Tools

Spreadsheet.

294 The Gateway spreadsheet is displayed.

To close this spreadsheet, choose File

Exit.

On the Exit Spreadsheet dialog, choose Discard.

Spreadsheets in Unigraphics NX The Modeling Spreadsheet The difference between the Gateway spreadsheet and the Modeling spreadsheet is that the Modeling spreadsheet can be used to modify the part while the Gateway spreadsheet cannot. One very common use of the Modelingspreadsheet is to assign the cells different values for a single feature. You can continue using the part uge_spreadsh.prt for the following example. First, you will need to be in the Modeling application.

Choose the Modeling icon. Use the MB3 pop-up menu to Replace the view with a FRONT view. This view displays some things differently than the trimetric view. Along with a wireframe view of the part, you see the dimensions (expressions) used to constrain the part. Most of these expressions begin with the small letter "p", but some begin with a capital letter (A = 125.0, for example).

295

The three expressions that begin with a capital letter define the three critical dimensions on this valve: Value A defines the overall length of the valve. Value B defines the diameter of the valve head. Value C defines the diameter of the stem.

Spreadsheets in Unigraphics NX A Typical "Family of Parts" Spreadsheet A "family of parts" spreadsheet was developed for this part. The three key values (the A, B, and C expressions) were given different values on the spreadsheet so that 5 different valves could be created from this solid model just by applying the values in a specific row on the spreadsheet to the model

Choose Tools

Part Families.

296 The Part Families dialog is displayed.

You can see the names of the three critical expressions (A, B, and C) displayed at the top of the upper list box.

Column A is for the names of the five different valves. The next three columns are for the values of the expressions A, B, and C for each valve. If you were to create a family of parts from this spreadsheet, five parts, each with slightly different sizes for length, valve head diameter and stem diameter, would be created.

297

Spreadsheets in Unigraphics NX Looking At the Family of Parts Spreadsheet On the Part Families dialog, choose the Edit option. The system displays the Family of Parts spreadsheet that was developed for this part.

Use File

Exit to close the spreadsheet.

OK the warning dialog. Cancel the Part Families dialog.

Spreadsheets in Unigraphics NX Migrating Spreadsheet Data

If you created a spreadsheet in Unix, you could easily convert it to an Excel spreadsheet and vice versa. You would use File Utilities Migrate Spreadsheet Data. Then, the next time you opened the spreadsheet, it would be in the new format. On Windows, you have the option of using either the Xess or Excel spreadsheet application. If you choose to utilize the Xess spreadsheet, you must have Exceed installed. You can set one of these as the default on the Spreadsheet Preference dialog. You would choose Preferences from the dialog.

Spreadsheet, then choose the preferred type of spreadsheet

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Spreadsheets in Unigraphics NX Closing the Part Close all parts, then continue on to another CAST course.

-CurvesOverview of Curves This course will show you how to create and edit wireframe curves. Audience This course is designed for all Unigraphics NX users. Prerequisites The only prerequisite for this course is that you should be familiar with the Unigraphics NX user interface and basic functions, such as how to open and save part files, change layer settings, use coordinate systems, and use views and layouts. If you are not familiar with the basics of Unigraphics NX, you should complete the Unigraphics NX Essentials course in the CAST Online Library.

299 Course Content This course contains the following lessons: Overview of Curves — a basic overview of curve characteristics and how to select geometry. Points and Point Sets — creating points and sets of points. Basic Curves — creating and editing lines, circles, arcs, and fillets using the Basic Curves

dialog and the dialog bar. Splines and Conics — creating splines and conic curves (ellipses, parabolas, hyperbolas,

and general conics). Additional Curve Options — creating chamfers, rectangles, polygons, offset curves, section

curves, intersection curves, and planes. Also, creating curves by joining, bridging, and simplifying, by wrapping or unwrapping onto a face, by projecting, and by extracting from a face. Editing Curves — editing curves using various techniques, such as changing parameters,

dragging geometry, trimming, dividing, and stretching. Part Files A number of part files have been supplied with this tutorial. Before you start, make sure you know where these part files are located. If you do not know where your part files are located, see your system administrator. The part files associated with this course are stored in the crv directory and their names also start with crv. You will not be asked to save your parts as you work through this course. Of course, if you wish to, you can. Just be sure you have write-access to the directory where you want to keep your personal part files.

Overview of Curves This lesson introduces you to curves in Unigraphics NX. You will learn about some of the characteristics of curves and how to select geometry and define locations. Curves include lines, arcs, circles, conics, and splines (free form curves).

Selecting Geometry

300

Whenever you are asked to select geometry, a cursor appears in the graphics area, with a selection ball at its center, as illustrated here.

It is important that you position the selection ball carefully when you select geometry. The desired object must be within the selection ball when you press MB1. You can change the size of the selection ball to make selecting easier by choosing Preferences Selection and selecting small, medium or large. You may also choose to have full-screen crosshairs displayed

Infer works differently.

Selecting Geometry Location Methods When defining locations for curve creation, you are often presented with the Point Constructor dialog. If you need a refresher on this, please refer to the Unigraphics NX Essentials CAST course. When using Basic Curves (lines, circles, arcs, fillets), you will get the following choices for locations: Inferred Point Cursor Location Existing Point End Point Control Point Intersection Point Arc/Ellipse/Sphere Center Quadrant Point

301

Select Face Point Constructor Most of the options work the same as they do on the Point Constructor dialog, or you can use the Point Constructor dialog itself.

Inferred Selection Infer will allow you to select End Points, Control Points, Arc/Ellipse/Sphere Centers, Cursor Locations, or curves themselves. Selection Principle Geometry must pass through or be inside the selection ball to be selected. If there is no geometry inside the selection ball, a Cursor Location is selected.

When a screen position (or "cursor location") is selected, this procedure is sometimes referred to as indicating, as in "Indicate a location for the center of the circle." Selection Principle If you select a curve such that one of its control points lies within the selection ball, that control point is selected. If a control point is not within the selection ball, the entire curve is selected. (See the following illustration.)

302

Preselection Highlighting Preselection highlighting lets you see what geometry is going to be selected before you actually select it. In the case of basic curves, preselection is on by default; you do not have to explicitly turn it on. You can control the selection and pre-highlight colors through the Visualization Preferences dialog, under the Color Settings tab.

303 Preselection highlighting is based on whatever object is within the selection ball of the crosshairs. Whatever is currently preselected is echoed in the Status area, i.e. Arc Center, End Point, Line, Arc, etc.

Quick Reference Chart: Inferred Selection Summary

Within the Selection Ball

Geometry Selected

Nothing

A cursor location

An existing point

The existing point

An endpoint or midpoint of a line, arc, or partial ellipse

The control point

An endpoint of a hyperbola or parabola

The control point

A knot point of a spline

The control point

A line, arc, circle, conic, or spline, but not one of its control points

The line, arc, circle conic, or spline

The marker at the center of an arc, circle, ellipse, or sphere

The center of the arc, circle, ellipse or sphere

Points and Point Sets In this lesson, you will learn how to create points and sets of points. Point Point Set You can also access the Point and Point Set functions by choosing from the menu bar.

304

Creating Points You can create points to permanently identify a location in space. To create individual points, you specify their location using the Point Constructor dialog. Open part file crv_points_1.prt from the crv subdirectory.

The part is a metric part containing some curves. Start the Modeling application and bring up the Point Constructor dialog. Choose the Modeling icon. Choose the Point icon

Creating Points Creating Individual Points

or Insert

Curve

Point.

305

The Point Constructor dialog is displayed.

Notice that the Infer icon is selected by default, and the name of the active point type is displayed at the top of the dialog.

Creating Points Using the Icons One way to specify a location is to use one of the icons to locate it relative to existing geometry, or to specify a cursor location. These methods extract the location of the selected geometry (or cursor location), and use it. The specified location is NOT associated with the selected geometry. Inferred Point Cursor Location Existing Point End Point Control Point Intersection Point Arc/Ellipse/Sphere Center Angle on Arc/Ellipse Quadrant Point

306 When you use the Cursor Location method, you need to be aware of the orientation of the Work Coordinate System (WCS) because the point is projected onto the XC-YC plane.

Creating Points Defining a Point at a Cursor Location You can specify an approximate location by indicating with the cursor. Be sure you are aware of the position of the WCS when you do this, because the point is projected onto the XC-YC plane. Choose the Cursor Location icon. Put the cursor anywhere in the graphics area and click MB1. A point is created where you indicated, with a ZC value of 0. Point objects are displayed as small "plus" signs. It is actually not necessary in most cases to choose the Cursor Location icon. If you are in the default Infer (or the Control Point) mode, and you indicate in an area where there is no existing geometry, a point is specified just as if you had used the Cursor Location icon. Notice that the XC, YC, and ZC values of the point are shown as the Base Point in the Point Constructor dialog. (Your values will be different than those shown in the illustration.)

Choose Reset at the bottom of the dialog to reset the values to all zeroes.

Creating Points Specifying Points with WCS Coordinates Notice that the WCS button is on.

307 This means that locations will be specified in WCS coordinates. If you wanted to specify a point in absolute coordinates, you would turn on the Absolute option. Key in XC=-32.0, YC=13.0, using the Tab key to move from one field to the next. (Leave ZC set to the default of 0.)

OK the dialog to create the point. It is displayed as a magenta "plus" sign, as shown below.

Creating Points Defining a Point at the Center of an Arc Choose the Arc/Ellipse/Sphere Center icon. Remember, there are two ways you can tell what the active point type is: The icon is highlighted, and The name of the icon is displayed at the top of the dialog.

Select the orange arc (or its center point marker).

308 A point is created at the center of the arc.

Creating Points Defining a Point Offset from a Base Point You can use the Offset option menu to create points that are offset from a specified point. First you will create a point offset from the end of the yellow line. Choose Reset to zero all values on the dialog. Set the Offset option to Rectangular.

Notice that there are five ways you can create an offset point. Rectangular will offset parallel to the coordinate system in use, WCS or Absolute. First, you must specify the base point, which is the point that the offset is measured from. In this case, that is the endpoint of the line. Choose the End Point icon. Select the right end of the yellow line to establish it as the base point.

Creating Points Finishing the Line

309

Now you must specify the distance to offset from the base point. Because you specified a rectangular offset, this is done in delta X, Y, and Z coordinates. Notice that the center of the dialog is now labeled "Enter WCS offset" and the text field names have changed.

Key in the following values: Delta-XC=-12.5 Delta-YC=12.5. OK the dialog. The offset point is created.

If Absolute had been selected instead of WCS, then the Offsets would be relative to the Absolute Coordinate System, and the offset values would be labelled Delta-X, Delta-Y, and Delta-Z. When you are through creating points, Cancel the dialog.

Creating Points Creating Sets of Points A more powerful and potentially useful method of point creation is where you create a set of points on a curve or face.

Choose the Point Set icon

or Insert

Curve

Point Set.

A list of the different ways you can create sets of points is displayed.

310

Notice the last option on the menu, which lets you group the points as you create them. This can be helpful later on, when you can select a group instead of having to select the points one at a time.

Choose Group Points - Off. The menu changes - the Group Points option is now on.

Creating Points Spacing Points Along a Curve You will create five points equally spaced along a selected curve. Choose Points on Curve.

The Points on Curve dialog is displayed. The Spacing Method button gives you the different spacing methods you can use.

311

For this exercise, you will use the default method - Equal Arc Length. First, you must select the curve that the points are to be spaced along. It does not matter where you select it. Select the bottom arc (the white one).

Key in 5 in the Number of Points field. Apply the dialog. Five points are evenly spaced from one end of the arc to the other.

NOTE: These are not related to the control points.

Creating Points Specifying a Start and End Percentage This time you need five points equally spaced along part of a curve. You can do this by defining a start and end percentage. Say you want the first point to begin 10 percent from one end and continue on through 75 percent of the curve.

312 Choose Select New Curve. Select the middle arc (the cyan one), toward the left end, as shown here.

Key in 10 in the Start Percentage field and 75 in the End Percentage field.

Apply the dialog. The five points are evenly spaced along the curve. However, this time the points start at a distance from the beginning of the curve (i.e., the end nearest where you selected it) equal to 10% of its length and stop at a distance from the beginning of the curve equal to 75% of its length.

Creating Points Specifying a Start and End Percentage Using Existing Geometry You can also define the Start Percentage, the End Percentage, or both by selecting geometry. Choose Select New Curve. Select the upper arc (the yellow one).

313

Notice that the cue line says that you can specify parameters or that you can infer the start percentage by selecting geometry. The geometry does not have to be on the curve. Select the blue point, just above the left end of the arc (avoiding its control points).

The point is projected down to the arc. The percentage value is calculated at that spot, and the value is displayed in the Start Percentage field in the dialog.

Creating Points Selecting the Second Limit Select the blue line, avoiding its control points.

The line is intersected with the arc and the percentage value is displayed in the End Percentage field in the dialog.

314

Apply the dialog. The points are evenly spaced between the projection of the selected point and the intersection with the line.

Creating Points Creating Point Sets in a Geometric Progression You can also create points that are spaced in a geometric progression. Set the Spacing Method option to Geometric Progression.

Choose Select New Curve. Select the green spline toward its left end.

315

Creating Points Setting the Parameters In order to space along the entire curve, you must set the Start and End Percentage back to their original values. Key in 0 for the Start Percentage and 100 for the End Percentage. You want each point to be 1.5 times as far along the curve as the last interval. Key in 1.500 in the Ratio field.

Apply the changes. The points are created as shown below. Notice that the distance from one point to the next is 1.5 times the previous distance as you progress along the curve.

Cancel the dialog.

Creating Points Deleting a Group of Points Remember that you turned on the Group option when you began creating point set. Now you will see how easy it is to select all the points from any of the four groups of points you just created.

316

Choose the Delete icon.

.

The Class Selection dialog is displayed. Choose Type. The Select by Type dialog is displayed. Choose Group and OK the Select by Type dialog.

Choose any point on the green spline.

OK the dialog. All the points on the green spline are deleted.

Grouping objects makes them easier to select. Close the part file.

317

Basic Curves In this lesson, you will learn how to create and edit basic curves (lines, circles, arcs, and fillets) using the Basic Curves dialog and the dialog bar to create this profile.

After the profile is created, you will use it to create this extruded body.

In order to do this you will want all the curves in the profile to be contiguous.

About the Profile Here are the overall dimensions of this profile.

318

To create it, you will need to use lines, circles, arcs, and fillets, but not necessarily in order. (You plan to achieve a contiguous profile by carefully trimming various curves that overlap.) All of the curves that define this profile will lie on the XC-YC plane of the current orientation of the WCS. So the ZC value of every curve will be zero. You will find it convenient to begin at the top right corner of this profile. This will mean, however, that you will need to key in negative values along the XC and YC axes.

This exercise is designed to show you as many curve creation and editing procedures as possible for instructional purposes. However, it does not cover every curve creation method. See the Modeling User Manual (online documentation) for more information about curve creation. This is not the only way this shape could be created, and may not even be the "best" way. It is just one example of how you could design this model.

About the Profile Opening a Standard Part File For this lesson, you will use a standard millimeter part file. Open part file crv_profile_1.prt from the crv subdirectory.

319

Choose the Open icon

or File

Open.

This is an empty metric part with the default settings. You will start the Modeling application. However, the curve creation options are available from many other Unigraphics NX applications also.

Choose the Modeling icon.

to start the Modeling application.

About the Profile The Insert Curve Cascade Menu

Before you begin, you should look at the options on the Curve menu. Choose Insert Curve. (If you have the toolbar configured to show it, you can also access the Curve functions by choosing the appropriate icon.) The Curve cascade menu is displayed.

You can see that there is an icon available on the Curves toolbar for every one of these options.

320 Besides Basic Curves, this menu contains items you can use to create: Points, chamfers and splines Rectangles and polygons Conics like ellipses, parabolas, etc. Planes

About the Profile The Basic Curves Dialog

Choose the Basics Curves icon

or Insert

Curve

Basic Curves.

The Basic Curves dialog is displayed, with the Line option selected by default.

The options on the Basic Curves dialog are used to create and edit the most commonly used 2D curves - lines, arcs, circles, and fillets.

About the Profile The Dialog Bar

When the Basic Curves dialog is displayed, the dialog bar is also displayed. The dialog bar is a series of text fields and icons in the form of a toolbar.

The location of the cursor in the graphics area is tracked in the XC, YC, and ZC fields in the dialog bar. These three fields are always available. The other fields vary depending on the active dialog icon. Because the graphics window is usually small when you are using the CAST Online Library, some of the dialog bar may not be visible. The dialog bar is a toolbar, so it can be picked up and moved. To do so, hold down MB1 on the left end of the bar (if it is not docked, you can

321 also select it in the bar above the icons), and drag it so you can see the area you are interested in.

When you key in values in the dialog bar, they are relative to the WCS, unless the Delta option in the Basic Curves dialog is on. In that case, the values you key in are relative to the previous point.

About the Profile Setting Tracking Preferences

Notice how, when you move the cursor around in the graphics area, the fields in the dialog bar are continually updated to reflect the current cursor location. You can turn this cursor tracking off. Choose Preferences

User Interface.

The User Interface Preferences dialog is displayed.

Make sure the General tab is selected and choose Tracking, under the Dialog Bar Options heading, to turn it off (no check mark).

Notice the Decimal Places text field. This lets you control the size of the fields in the dialog bar - generally how many decimal places are displayed. OK the dialog. Check out the difference in the dialog bar.

322 Move the cursor around in the graphics area and watch the text fields in the dialog bar again. Notice that now the XC, YC, and ZC fields do not change as the cursor is moved.

About the Profile Creating Lines

First, you need to create a vertical line downward from the origin of the WCS, with a length of 138 mm. The cue tells you to indicate the start of the line. You want this line to start at the origin of the WCS, so you need to enter XC=0, YC=0 in the dialog bar. In the Unigraphics NX Essentials course, you learned the general rules about entering text in text fields. These rules also apply to the dialog bar. A text field must have focus before you can key text into it. You can click once in a text field to position the cursor and insert characters into the text that is already there. You can double-click in a field, or Tab into it, to highlight all of the text. The characters you type will then replace the current contents of the field.

About the Profile The Dialog Bar During Line Creation

The following icons are available in the dialog bar during line creation (in addition to the XC, YC, and ZC fields, which are always available). Length - The length of the line. Angle - The angle of the line, either from the XC axis or from another line. Offset - The distance to the base line (when creating a parallel line).

About the Profile Creating a Vertical Line

323 You can begin by creating the outermost vertical line that will define the right side of this profile.

Since you want the starting position of this line to be accurate, you can use the dialog bar to define its start position at the origin of the WCS. Double-click in the XC field, so that all the text in the field is highlighted.

This means that the field has focus and, when you start typing, the current contents of the field will be replaced. Key in 0 (zero) - DO NOT PRESS ENTER. Press the Tab key to move to the YC field (all the text will be highlighted) and key in 0 (zero). It is not necessary to enter anything in the ZC field, which is set to zero by default. The only time you need to enter a ZC value is if you are specifying a location off the XC-YC plane. Press Enter.

About the Profile Finishing the Line

You have now specified your first point, and an asterisk is displayed in the graphics area at the origin of the WCS.

324

Move the cursor around in the graphics area. You can see a line "rubber-banding" from the location you specified. The system knows where one end of the line is, but not the other.

If you enter a value in the Angle Increment field in the dialog, the line will rubber-band by angular increments. (This is one way you can get a line at a particular angle.) The cue asks you to indicate the end of the line. Since the XC field is already zero, you only need to key in the length of the line along the negative YC axis. Double-click in the YC field in the dialog bar, key in -139, then press Enter.

Your first line is created.

Use the Fit icon

or MB3

Fitto fit the view.

You have created a vertical green line 139 mm long.

325 You can perform a "fit" at any time during this lesson to help you visualize the curves you are creating.

About the Profile Setting the Fit Percentage

The Fit Percentage lets you have some space around your geometry after you do a Fit.

Choose the Visualization Preferences icon

or Preferences

Visualization.

Choose the Screen tab.

Using the slider bar, set the Fit Percentage to approximately 80, then OK the dialog.

Fit the view again. Now you should have plenty of working space as you create the rest of the curves.

About the Profile String Mode Move the cursor around in the graphics area again. Now you can see that a new line rubber-bands from the end of the line you just created. This is because String Mode is active.

326

Notice in the Basic Curves dialog that the String Mode button is on.

This means each curve you create will be connected to the previous curve, unless you choose Break String.

About the Profile The Snap Angle

The next line needs to be horizontal, but its length is not critical. You can use the snap angle to create lines that are exactly vertical or horizontal. When you indicate the endpoint of a line, and the line falls within the snap angle of being horizontal or vertical, the line "snaps" so that it actually is vertical or horizontal. Because the second point in the example below is within the snap angle, the line snaps to horizontal.

In the next example, however, the second point is outside the snap angle. Therefore, the line goes directly to the second point.

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About the Profile Setting the Snap Angle Preference Choose Preferences

Sketch.

The Sketch Preferences dialog is displayed, showing the current setting of the snap angle, which is 3 degrees by default.

You can set the snap angle to any value between 0 and 20. Change the Snap Angle value to 7 degrees, then OK the dialog. If you do not want your lines to snap to vertical or horizontal, you can set the snap angle to zero. NOTE: The snap angle only affects line creation when the Point Method is set to Inferred

Point.

About the Profile Creating a Horizontal Line

For the next curve in this profile, you can create a horizontal line in the negative XC direction from the lower end of the vertical line.

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Because you know you will edit this line later when you create the large arc, its exact length is not critical. So you can just indicate its end point. However, it must be exactly horizontal, so you want to be sure that you indicate within the snap angle you have defined (7 degrees). Position the cursor as shown here, with the rubber-banding line nearly horizontal, then press MB1.

A horizontal line is created. Since the second point was within the snap angle, the line snapped to horizontal.

More About: Horizontal and Vertical Lines

There are a number of ways you can create vertical and horizontal lines: You can use the snap angle to let the lines "snap" to horizontal or vertical, as shown in the previous exercise. (This only works when the Point Method is set to Infer.) You can specify the first point, then use the XC or YC button in the "Parallel to" section of the Basic Curves dialog.

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You can use the Angle field in the dialog bar to create a line at exactly 0 or 90 degrees (or change the angle immediately after you create the line). You can set the Angle Increment value in the Basic Curves dialog to a non-zero number (such as 90, 45, or 30) and "drag" the rubber- banding line - it will snap to multiples of the angle you key in.

About the Profile Breaking the String

Now you need to create another horizontal line starting at the top of teh vertical line, but first you must break the string. To do this, you could go to the dialog and choose Break String. However, notice that the Break String button has a black outline around it.

This box signifies that Break String is the "default action". This means you can use MB2 to "choose" this button. Press MB2 to break the string. Notice that there is no line rubber-banding now, and that the Break String button is grayed out. Any time you see a black outline like this around a button, in any Unigraphics NX dialog, you can activate the button by pressing MB2. You will not need to use the String Mode for the rest of this lesson. Choose String Mode to turn it off.

330 Notice that the Unbounded option, which was grayed out, is now available. If you turn that option on, the lines you create will go all the way out to the borders of the view.

About the Profile Selecting Existing Objects

Most of the curves that you create will probably be related to existing geometry in some way. There are some basic principles to understand about selecting existing geometry during curve creation. There are three things you can select from existing geometry: Control points, End Points, Arc Centers, Intersection Points, and Quadrant Points Existing curves Edges or faces from solid or sheet bodies When you move the cursor over geometry while the Basic Curves dialog is active, the geometry is highlighted before you select it. (Remember, this is called "preselection highlighting" or "pre-highlighting" - the preselection and selection colors are set on the Selection Preferences dialog.) Geometry is pre-highlighted in Basic Curves mode, regardless of the setting of the Preselection option on the Selection Preferences dialog.

About the Profile Making Selections Move the selection ball of the cursor over the vertical line. Notice that the line is highlighted in the preselection color, similar to what occurs when other types of geometry are pre-highlighted. However, when you are in the Basic Curves dialog, control points are also displayed, as small circles in the system color.

331 The Status area also shows you what is currently preselected.

Move the cursor over the upper endpoint of the vertical line.

Now the Status area shows you that the line endpoint is preselected:

In this way, you can be sure of what you are going to select before you actually select it.

About the Profile The Infer Method

As you learned earlier, the Infer method lets you select many different types of points. The following chart summarizes the points that Infer will find for some common curve types.

332

About the Profile The Point Method Options

The Point Method menu lets you choose how you specify a point location. Click on the Point Method button to display the option menu.

Hold the cursor over each of the options to see their names. The following chart summarizes the Point Method options. Inferred Point

Infers the point from the geometry in the selection ball.

Cursor Location

The next several options work the same as they do on the Point Constructor dialog.

Existing Point End Point Control Point Intersection Point Arc/Ellipse/Sphere Center Quadrant Point Select Face

Use this option when you want to select a face to limit a line.

Point Constructor

This option brings up the Point Constructor dialog.

In almost all cases, you can select the point you want using the Infer option. Some exceptions are intersection points, quadrant points, and offset points.

About the Profile Creating a Horizontal Line Using the Infer Method

333 The next curve you can create for this profile is the upper horizontal line. It is similar to the lower horizontal line in that its exact length is not critical. (You plan to edit it later when you add the arc on the left.) Since this line must be exactly horizontal, you will want to keep its left end within the snap angle.

Move the cursor over the upper endpoint of the vertical line, verify that the Status area says "Line Endpoint", then click MB1 to select the point. Indicate a cursor position to the left, so that the line snaps to horizontal (the length is not important). Another horizontal line is created. Your model should look like this:

About the Profile Offseting a Line from Another Line

For the next curve, you can create the vertical line on the left side of this profile.

334 This line will define the left edge of the profile and must be placed at a specific distance from the right vertical line.

There are several ways you could create this line, but one way to do it is to simply offset the existing vertical line. The offset line is created on the side of the base line where the center of the selection ball is when the base line is selected.

About the Profile Creating an Offset Line Select the vertical line with the center of the selection ball to the left of the line. (Be careful not to select a control point!)

Drag the dialog bar if you need to, to be able to enter text in the Offset field.

335

Be careful! The Offset and Length the far right end of the dialog bar.

icons look very much alike - the Offset field is on

To be sure you are getting the right icon, you can always hold the cursor over the icon and its name will be displayed, as with all Unigraphics NX icons. Highlight the Offset field, key in 130 and press Enter.

When focus is in the XC, YC, or ZC field and you press Enter, you are specifying a location. If focus is in any other field, you are specifying parameter values, not a location. Use Fit so you can see all your geometry.

Leave the part file open.

About the Profile Offsetting Another Line There is a little jog on the right side of the profile.

336 Before you create the small arc that defines this jog, you can create the vertical line that will be used to define the lower right side of the profile.

Using the same method, create another vertical line offset to the left of the first vertical line by 3 mm. Select the vertical line, with the center of the selection ball to the left of the line. (Be careful not to select a control point!) Key in 3 in the Offset field

and press Enter.

Creating Circles When you are in circle creation mode, some of the options on the dialog will change. Unbounded and String Mode will be grayed out - they do not apply in Circle mode. The Multiple Positions option is added. This will become available after creating the first circle. It will be described later.

337

Open part file crv_profile_2.prt. Choose the Open icon

or File

Open.

Start the Modeling application, if necessary. Choose Application

Modeling.

The geometry in this part file continues where you left off in the last section. Display the Basic Curves dialog. Choose the Basic Curves icon

or Insert

Curve

Basic Curves.

If you did not start at the beginning of this lesson, you may need to reset some of the session dependent settings. Turn off String Mode on the Basic Curves dialog. Use Preferences User Interface to turn off tracking. On the Visualization Preferences dialog set the Fit Percentage to 80. Use Preferences Sketch to set the Snap Angle to 7.

Creating Circles Basic Curves Pop-Up Menus

Your next task will be to create a circle, which you will later trim into an arc. You could choose the Circle icon to switch to circle creation mode. However, there is a shortcut you can use.

338 When you are in the Basic Curves dialog (in line, arc, or circle creation, or in Edit Curve Parameters), there are special pop-up menus available. These menus let you bring up frequently used options without moving the cursor out of the graphics window. Put the cursor in the graphics area, hold down the Shift key, and click MB3. The following pop-up menu is displayed.

Choose Circle from the pop-up menu. Notice that the Circle icon

in the dialog is now active, just as if you had selected it.

The options on this pop-up menu will be different, depending on whether you are in line, arc, or circle creation, or in Edit Curve Parameters mode.

Creating Circles The Dialog Bar During Circle Creation

The following icons are available in the dialog bar during circle creation (in addition to the XC, YC, and ZC fields, which are always available). Radius - The radius of the circle. Diameter - The diameter of the circle. The icons for Start Angle and End Angle are greyed out for Circle creation. They are discussed as part of the Arc creation portion of the lesson.

Creating Circles Creating a Circle The next curve you can create on this profile is the smaller arc on the left side of the profile.

339

There are several ways you could do this. In this case, however, a circle that defines the radius of this arc will work fine if you trim the circle later.

You do know that the radius of this arc must be 13 mm. In order to place the circle correctly, its centerpoint must be at this exact location in relation to the origin of the WCS.

Look at the available fields in the dialog bar. You may have to drag the bar location to be able to see them all. (You may notice that there are two other fields in the dialog bar, but they are grayed out. They will be explained in the section on creating arcs.)

Creating Circles Creating the Circle Notice that the cue is prompting you to indicate the center of the circle. This circle's center needs to be 124 mm to the left and 55 mm below the origin of the WCS.

340 Key in XC=-124, YC=-55 in the dialog bar for the center of the circle, then press Enter. An asterisk appears at the specified location.

Move the cursor around in the graphics area; a circle rubber-bands around the position you keyed in.

Creating Circles Inferring the Diameter of a Circle

When a curve is rubber-banding, as the circle is now, it will change in response to whatever is currently inside the selection ball. Move the cursor over the upper horizontal line avoiding the control points, and notice that the circle becomes tangent to the line.

341

Notice also that the Status area tells you that the circle is now tangent to another object. Move the cursor over the endpoint of the line, then over other geometry. Watch the resulting circle, and the feedback in the Status area.

Creating Circles Completing the Circle

The exact size of this circle is not critical at this point, so you can just infer its diameter. Indicate approximately as shown to create the circle - the exact size does not matter.

(Notice that the Multiple Positions option is now available.

If you turned it on, a new circle exactly like the current one would be created at each point you specified.) The circle you just created has an arbitrary radius value. But you need the radius to be exactly 13 mm. In most cases, you can still change a curve by keying in new parameter values in the dialog bar immediately after you create it, while it is still highlighted.

342

Key in 13 in the Radius field

in the dialog bar, then press Enter.

The radius is changed to the specified value. Notice that the circle is still highlighted, which lets you know that you could continue to change parameter values in the dialog bar. However, you could start a new circle by simply specifying a new center point, or you could choose another icon to create a different type of curve.

Creating Circles Creating Arcs Switch to arc creation mode, either by choosing the Arc icon or by using the Shift-MB3 pop-up. When you are in arc creation mode, there are several differences in the dialog. The Creation Method section is added. Full Circle is added. This lets you create a circle using the arc creation methods. Alternate Solution is added. This lets you create the complement of an arc.

Creating Circles The Dialog Bar During Arc Creation

The following icons are available in the dialog bar during arc creation (in addition to the XC, YC, and ZC fields). Radius - The radius of the arc.

343

Diameter - The diameter of the arc. Start Angle - The beginning angle of the arc. End Angle - The ending angle of the arc. The Start Angle and End Angle are measured in a counterclockwise direction from an imaginary line through the center of the new arc and parallel to the +XC axis.

Creating Circles Creating an Arc Using the Center, Start, End Method

The next curve you will create on this profile is the larger arc. (You will notice that you are not creating these curves in a continuous manner. Later you will create the "connecting" curves that will make the profile contiguous.) The larger arc must have a radius of 45.0 mm.

To place the arc at the correct location in this profile, its centerpoint must be placed at the position shown below in relation to the origin of the WCS.

344 To create this curve, you would first define the position of the arc centerpoint, then define the location of each end of the arc.

Creating Circles Locating the Center of the Arc

Notice that the cue is prompting you to indicate the start of the arc. That is because you are using the "Start, End, Point on Arc" method, which is the default. This arc has a specific center point, so you must change the creation method. Choose Center, Start, End.

Now the cue is asking for the center point of the arc. Using the dialog bar, specify the center of the arc at XC=-76, YC=-118 and press Enter.

An asterisk appears at the point you specified, and a line rubber-bands from the point.

Creating Circles Specifying the Arc Start Point

The next point you indicate will establish the start angle and the radius, although either of these can be changed after the arc is created. In this next step the exact location of the arc is not critical because you are going to key in an exact radius for it.

345 Indicate a point approximately as shown here.

Creating Circles Finishing the Arc Move the cursor around. Notice that now an arc is rubber-banding. The radius of the arc is equal to the distance between the two points you have specified.

Drag the arc around until it looks similar to the illustration below, then press MB1.

Use the dialog bar to change the radius to 44 and press Enter. The Arc is now complete. Refresh the view. Choose View

Refresh or press F5.

346

At this point you could change the Start Angle and/or End Angle in the same way that you changed the radius - by keying in new values in the dialog bar. Or you could just start creating a new arc by specifying a new center point.

Using the "Start, End, Point on Arc" Method

You can create an arc by specifying its endpoints and a point on the arc. To do this, you would: Choose the Start, End, Point on Arc creation method. Specify two points. The arc would then rubber-band between the points as shown here.

You would then complete the creation of the arc by: selecting a curve (to make the arc tangent to the curve), or specifying or selecting a point (to make the arc pass through the point).

Creating Circles Creating a Line at an Angle to Another Line

You have established seven curves that outline the profile.

347

You are almost ready to begin trimming these curves to make them contiguous. Before that, however, you need to create an angled line between the smaller and larger arcs on the left side of the profile.

One way to do this is to use an existing line as the reference, then key in the angle between them.

Creating Circles Locating the Arc Center

The angled line must start at the arc center of the circle. Its exact end point is not critical as long as the angle between this line and the left vertical line is 45 degrees.

348

First, you must switch back to line creation mode. Use Shift-MB3 to bring up the pop-up menu, then choose Line. The cue is asking you to specify the start of the line. Select the center of the circle as the start point of the line (the small red cross-hairs will appear at the center of the circle when you move the cursor there).

Creating Circles Selecting the Reference Line

As always, the line rubber-bands from the point you specified. You need to define the line you want to use as a reference. In Unigraphics NX, angles are measured in a counterclockwise direction. Therefore, when you needed an angle to be measured in a clockwise direction, you would use a negative angle value. Key in 45 in the Angle field

then press the Tab key (do not press Enter).

Select the left vertical line, avoiding its control points.

349

Creating Circles Finishing the Line Move the cursor around and watch the graphics area. The line rubber-bands parallel, perpendicular, and at an angle of 45 degrees to the base line you selected, depending on the location of the cursor.

With the line in "angle" mode, click MB1 to establish the length of the line approximately as shown. (Its exact length is not critical.)

What if, for example, I wanted to "fix" a rubber-banding line in perpendicular mode, so that I could move the cursor wherever I wanted and the line would remain perpendicular?

350 When the line is rubber-banding, the Lock Mode command on the dialog is the default action (remember, that means it has the box around it). You would get the line rubberbanding perpendicular to the base line, then press MB2 to activate lock mode. Now you can move the cursor anywhere, and select other geometry, etc. - the line is locked into perpendicular mode. More About: Creating a Line at a Fixed Angle

Besides creating a line at an angle to another line, you can also create a line at a fixed angle relative to the +XC axis. To create a line at a fixed angle, you would: Establish the first point (unless you are in String Mode, in which case the first point of the new line is the last point of the previously created curve). Either key in a length and angle in the dialog bar and press Enter -OR- indicate the endpoint of the line anywhere and then key in the angle. The angle is always measured in a counter- clockwise direction from the +XC axis. For example, the line below is at a negative 45 degrees.

Creating Fillets Your next task will be to trim up your geometry by adding a radius on some corners. To do this, you can create a number of fillets. Open part file crv_profile_3.prt. Choose the Open icon

or File

Start the Modeling application, if necessary. Choose the Modeling icon.

.

Open.

351 The geometry in this part file continues where you left off in the last section. Display the Basic Curves dialog. Choose the Basic Curves icon

orInsert

Curve

Basic Curves.

If you did not start at the beginning of this lesson, you may need to reset some of the session dependent settings. Turn off String Mode on the Basic Curves dialog. Use Preferences User Interface to turn off tracking. On the Visualization Preferences dialog set the Fit Percentage to 80. Use Preferences Sketch to set the Snap Angle to 7. Choose the Fillet icon

or use the Shift-MB3 pop-up to switch to fillet creation mode.

The Curve Fillet dialog is displayed.

Creating Fillets Creating Simple Fillets

Notice that, when you are in fillet creation mode, the dialog bar is not displayed. This is also true when you are in Trim mode. Move the cursor over the icons on the dialog, to see their names. You can begin by creating a fillet at the top and bottom of the right side of the profile.

352

To do this you can use a fillet procedure that will automatically trim the vertical and horizontal lines as you create the fillet. Notice that the Simple Fillet icon is active by default. Simple fillets have several unique characteristics: They can only be created between two lines. You must be able to get both lines in the selection ball at the same time. (Remember, you can change the size of the selection ball using Preferences Selection.) Both lines are trimmed to the arc that is created. If any of these characteristics do not apply to the fillet you are creating, use the 2 curve fillet instead. When you are creating a fillet, you need to specify the radius before you start.

Creating Fillets Creating the First Fillet

The first fillet will be a 6 mm simple fillet between the lower horizontal line and the inside vertical line.

If you need to, key in 6 in the Radius field.

353

(You can also establish the radius by choosing Inherit, then selecting an existing arc, circle or fillet.) Move the cursor to the corner, making sure that both lines are in the selection ball at the same time. (It does not matter which one is highlighted.) Then click MB1.

The fillet is immediately created, and both the lines are trimmed back.

If you get the wrong fillet, just choose MB3

Undo and try again.

Creating Fillets Creating Another Simple Fillet

You need to create one more fillet between the top horizontal line and the outside vertical line.

354 Because you want to trim both lines, you can use the simple fillet procedure again.

Choose the Zoom icon curves.

or MB3

Zoom to zoom in on the upper right corner of the

Creating Fillets Creating the Fillet With both lines in the selection ball, click MB1 to create the fillet. (Be sure that the other vertical line is not in the selection ball too - otherwise, you will get an error message.)

The fillet is created. (Again, if you have created the wrong fillet, just undo it and repeat the procedure.)

Fit all the geometry back in the graphics area by using the Fit icon

or MB3

Fit.

355

Creating Fillets Creating a 2 Curve Fillet The next fillet needs to be between the left end of the larger arc and the lower end of the angled line.

Because one of these curves is an arc, you must use the "2 Curve Fillet" procedures to create this fillet. Choose the 2 Curve Fillet icon. If this fillet had a different radius, you would enter a new radius value now. Since this will also be a 6 mm fillet, like the previous ones, you do not need to change the value. Notice that the Trim First Curve and Trim Second Curve options are no longer grayed out.

If you did not want to trim one of the curves, you would turn that button off. For a 2 curve fillet, it is important to select the curves in the correct order. The fillet is created in a counterclockwise direction from the first curve to the second.

Creating Fillets Creating the Fillet Select the angled line, then the arc.

356

Even though this line and arc do intersect, it is not a requirement. The system will attempt to extend the curves to the fillet if possible. For any two curves, there are four possible fillets. You need to let the system know which one of those fillets you want. Indicate in the approximate center of the fillet.

The fillet is created and both curves are trimmed to the ends of its 6 mm radius.

Creating Fillets Creating a 2 Curve Fillets Between the Larger Arc and the Bottom Line

You need a fillet between the other end of the large arc and the lower horizontal line. Create another 2 curve fillet, between the large arc and the lower horizontal line. (Remember to select the curves in a counterclockwise direction.) Select the arc, then the horizontal line. Indicate in the approximate center of the fillet.

357

Creating Fillets Creating a 2 Curve Fillet Between the Vertical Line and the Circle

You need a fillet between the left vertical line and what will become an arc.

This means you must select the vertical line and the circle, then create a fillet that will trim both the line and the circle.

Remember: Select the curves in a counterclockwise direction. Use Undo if you do not get the fillet you want. Create a 2 curve fillet between the left vertical line and the circle. Indicate the approximate center of the fillet as shown.

358

Refresh the view.

Creating Fillets Creating a 2 Curve Fillet Between the Trimmed Circle and the Angled Line

Your last fillet on this side of the profile needs to be between the small arc (originally a circle) and the angled line.

This means you must select the trimmed circle (now an arc) and the angled line, then indicate where the center of the fillet should be placed (so that the system will correctly trim the arc and the angled line). Create one more 2 curve fillet, this time between the arc and the angled line. Indicate the approximate center of the fillet as shown.

359 Your model should now look like this - you are almost finished.

Editing Curve Parameters Open part file crv_profile_4.prt. Choose the Open icon

or File

Open.

Start the Modeling application, if necessary. Choose the Modeling icon.

The geometry in this part file continues where you left off in the last section. Display the Basic Curves dialog. Choose the Basic Curves icon

or Insert

Curve

Basic Curves.

If you did not start at the beginning of this lesson, you may need to reset some of the session dependent settings. Turn off String Mode on the Basic Curves dialog. Use Preferences User Interface to turn off tracking. On the Visualization Preferences dialog set the Fit Percentage to 80. Use Preferences Sketch to set the Snap Angle to 7. When you are in the Basic Curves dialog, there is an Edit Curve Parameters icon available. This icon works pretty much the same as the corresponding icon on the Edit Curve dialog.

360

The Edit Curve dialog will be discussed in more detail in a later lesson. However, this lesson will show you how to use this option without leaving the Basic Curves dialog.

Editing Curve Parameters Preparing to Change the Length of a Line

Up to now you have ignored the upper horizontal line. When you constructed it, you knew that you would edit it to the required length. This horizontal line will be tangent with an arc at its left end.

Therefore, before you create the arc, you will want to change the length of the horizontal line to its correct value. To do this, you can use the edit function of the Basic Curves dialog. (It looks just like the Edit Curve Parameters dialog.) Choose the Edit Curve Parameters icon

on the Basic Curves dialog.

When you are in edit curve parameters mode, the Basic Curves dialog changes. The curve creation options are grayed out.

361 A section is added for arc/circle editing methods.

The Display Original Spline toggle button is added. This option lets you display the original condition of a spline as you edit it.

A section is added that allows you to choose how to edit associative curves.

These additional options are some of the options that are available when you use Edit Curve Parameters from the Edit Curve dialog. (Again, they will be explained in more detail in a later lesson.)

Editing Curve Parameters Changing the Length of a Line

You must make the top horizontal line 76 mm long (measured from the origin of the WCS). The place where you select the line is important, because the endpoint nearest where you select is the one that moves - the other end remains stationary. Select the top horizontal line to the left of the midpoint, avoiding the control points.

When you select the line, the Length field in the dialog bar is highlighted, so you do not have to double-click in the field.

362

Key in 76 in the Length field

of the dialog bar and press Enter.

The length of the line is changed.

Editing Curve Parameters Creating an Arc Tangent With the Horizontal Line

Since the right end of the arc must be tangent with the left end of the horizontal line, you know that the centerpoint of this arc must be placed directly below the end of the line.

You also know the radius of this arc.

So one way to create this arc is to first define its center point, then its start point, and finally its end point. Choose the Arc icon

or use the Shift-MB3 pop-up to switch to arc creation mode.

If the Center, Start, End creation method is not active, turn it on.

363

Editing Curve Parameters Defining the Centerpoint of the Arc Using the Point Constructor

The cue asks you to indicate the center of the arc. Since this point will be directly below the left endpoint of the top horizontal line, you can use this control point to define the exact location of the arc centerpoint. Choose Point Constructor

from the Point Method menu.

The Point Constructor dialog is displayed, with the Inferred Point icon highlighted. You will use the Rectangular Offset method to define the arc center. Before you start, notice that the heading above the text fields says "Base Point".

Set the Offset option to Rectangular.

Editing Curve Parameters Defining the Offset

The dialog still says "Base Point", but now this has added significance. Since you are in Rectangular Offset mode, the base point is not actually created. The defined point will be measured from the base point. Move your cursor over the left endpoint of the horizontal line.

364 Notice that, even though you are in Infer selection mode, the control points are not highlighted, as they are when you are in the Basic Curves dialog. That special kind of highlighting only occurs when the dialog bar is displayed. Select the endpoint as the base point. The dialog changes - you are now asked to provide delta values from the base point you just specified.

The point you want to specify as the center is 171 mm below the base point (which will also be the radius of the arc). Key in -171 in the Delta-YC field.

OK the dialog.

Editing Curve Parameters Finishing the Arc

The center point is highlighted with an asterisk. If you need to, use Zoom In/Out to see the centerpoint of the arc. Now you must define the first point on the arc. Choose Back to return to the Basic Curves dialog. Notice that a line is rubber-banding from the center point you defined. Also, the Point Method has been set back to Infer, and the cue asks you to define the start point of the arc. Select the left endpoint of the line (the same point you used as your base point). Notice that

365 the control point highlighting is back!

Now the rubber-band image describes the arc itself, and its "open" end follows your cursor. The exact length of this line is not critical because you plan to trim it later. Drag the arc until it looks approximately like the illustration below, then press MB1.

Editing Curve Parameters Adding a Fillet Between the Vertical Line and the Arc

You can finish this side of the profile by creating a fillet between the arc and the vertical line.

Because one of these curves is a line and the other an arc, you will need to use the 2 curve fillet procedure. Switch to fillet creation mode. Either choose the Fillet icon menu.

, or choose Fillet from the Shift-MB3 pop-up

366 Be sure the dialog is still set to the 2 Curve Fillet mode, and the radius should still be set to 6 mm. Create a 2 Curve Fillet with a 6 mm radius, between the new arc and the left vertical line. (Remember, select the curves in a counterclockwise direction.) Indicate the approximate center of the fillet as shown.

Editing Curve Parameters Creating a 2 Curve Fillet Through a Point

There is one more operation you need to do to finish this profile, the jog on the right side.

The arc between the two vertical lines could be treated like the arc you created on the top horizontal line. But there is another way you can create this arc, by creating a fillet that goes through a point. One of the possibilities with the 2 Curve Fillet procedure is to use a point instead of a curve to define one end of the fillet.

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You control the shape of the fillet with its radius value and the point and curve you select. Zoom in on the upper right corner of the model.

Key in 18 in the Radius field.

Editing Curve Parameters Using the Point Constructor to Define One End of the Fillet

The top end of the fillet must be placed this distance below the current top endpoint of the vertical line.

Since the outer vertical line was originally created at the origin of the WCS, it won't be necessary to use a rectangular offset. When you want to define a point rather than select a curve, you use the Point Constructor option.

368 Choose Point Constructor.

Enter -37 in the YC field. (Be sure XC and ZC are set to 0).

OK the dialog. The point, which lies on the vertical line, is defined. The fillet will pass through this point and connect with the line when you trim it later.

Editing Curve Parameters Selecting the Second Object for the Fillet Choose Back to return to the Curve Fillet dialog. The cue tells you to select the second object. Select the inner vertical line.

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Indicate in the approximate location of the center of the fillet.

The fillet is created, and the outer vertical line is trimmed back, but the line is not trimmed because it was not selected as part of the fillet creation.

Choose Back to return to the Basic Curves dialog. You can also create a fillet that is tangent to three curves at once. To find out more, select the link below.

Creating a 3 Curve Fillet

You can also use the 3 Curve Fillet icon

to create a fillet between three curves.

370 To create a 3 curve fillet, choose the icon, select the three curves (#1, 2, and 3 below), and indicate approximately in the center of the fillet (#4 below). If any selected curve is an arc, you are asked to specify the location of the fillet relative to the arc.

When you create a 3 curve fillet, the Radius field is grayed out - the system determines the radius needed to maintain tangency to the three selected objects. The order of selection of the curves is not important, except that you can specify trimming on or off for the first and third curves, and you choose whether to delete the second curve or not, on the Trim Options part of the dialog.

Editing Curve Parameters Trimming a Line

The last thing you need to do is trim the outer vertical line back to the fillet you just created. You can use the Trim icon on the Basic Curves dialog to trim curves. It works the same as the Trim Curve icon on the Edit Curve dialog, which will be discussed in more detail in a later lesson.

Choose the Trim Curve icon. You will need to pick the bottom of the line, so you need to fit the geometry back in the graphics window.

Fit the view.

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Change the Method to Find Intersections option to Shortest 3D Distance.

Be sure that the Associative Output option is off. Be sure that Input Curves is set to Replace.

Editing Curve Parameters Trimming the Line

The cue asks you to "Select objects to define the first trim boundary". This is the object that the line will be trimmed to, which in this case is the fillet. Set Filter to Point, and select the upper end of the fillet between the two vertical lines.

Now the cue asks you to select the objects to define the second trim boundary, which you would use if you wanted to trim both ends of the line at once.

372 Since the other end of the line is already correctly trimmed, you do not need to specify a second bounding object. Choose the last selection step icon, String to Trim

(or use MB2).

The cue line asks you to select the curve you want to trim. Select the outer vertical line near the lower end.

The line is trimmed, and your model is complete.

Cancel the Trim Curve dialog.

Editing Curve Parameters Extruding the Profile

Now that the profile is created, you will use it to create this extruded body.

373 Choose MB3

Orient View

Isometric.

Choose the Extrude Body icon. The Extruded Body dialog displays. Choose the Chain Curves option. The Chaining dialog displays. Select any one curve. OK the Chaining dialog twice. OK the Extruded Body dialog. Editing Curve Parameters Creating the Extrusion Use MB2 to accept the Direction_Distance option. You can accept the direction of the vector arrow (pointing upward). Use MB2 to OK the Vector Constructor dialog. Set the Start Distance to 0. Set the End distance to 30. Leave the Frist Offset, Second Offset, and Taper Angle fields set to zero. OK the Extruded Body dialog. The extruded body is created.

If you wish, Shade and Rotate the extruded body. Cancel the Extruded Body dialog. Close all part files.

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Splines and Conics This section gives you an overview of spline curves in Unigraphics NX.

Degree of a Spline Every spline has a degree, which refers to the degree of the polynomial that defines the curve. The degree is generally one less than the number of points in a spline segment. For this reason you cannot have a spline with less points than its degree. If you choose to create a single segment spline, the curve's degree depends on the number of points you specify. Therefore, you cannot supply the degree and the option is unavailable. The minimum number of points required for all splines is one more than the degree of the spline. The following sections compare the advantages and disadvantages of low-degree and highdegree splines.

Degree of a Spline Low Degree Splines It is recommended that you use cubic splines (a degree of 3) whenever possible.

Why should you use cubic splines? They are more flexible. They follow their poles more closely.

375 They result in faster performance during subsequent operations (such as machining, display, etc.). Many systems only accept cubics, therefore, the use of cubics makes it more likely that you can transfer data to other systems.

Degree of a Spline High Degree Splines

What are the characteristics of high degree curves? They are "stiffer" (you have to move poles further to produce any appreciable change) They may introduce unwanted oscillations in the curve They reduce the chance of transferring data to other systems which may not support them They can result in slower performance during subsequent operations

Degree of a Spline Spline Data The following data is stored for a spline: The degree of the curve An array of poles (vertices) for the curve Parameter values which define the segments of the curve Defining Points (if so created) Fit weight (if so created) All Unigraphics NX splines are Non-Uniform Rational B-Splines, or NURBS. NURBS can also be thought of as free form curves. Defining Points vs. Knotpoints There are two types of points associated with splines:

376 Defining Points - These are the points used to define the spline. If a spline is created through poles, it does not have any defining points. Knotpoints - These are the endpoints of the spline segments. Single segment splines have only two knotpoints (at each end of the spline). For a spline with a degree of 3 (a cubic spline), the defining points and knotpoints are the same. Certain kinds of editing procedures will remove the defining points on a spline. This will be covered in a later section.

Creating Splines There are four different methods you can use to create a spline.

Open part file crv_splines_1.prt from the crv subdirectory.

Start the Modeling application. Choose the Spline icon The Spline dialog appears.

or Insert

Curve

Spline to bring up the Spline dialog.

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Creating Splines Creating a Spline By Poles When a spline is defined "By Poles", it gravitates toward the points you select (referred to as poles), but does not pass through them (except at the endpoints).

Choose By Poles from the dialog. The Spline By Poles dialog is displayed. For both By Poles and Through Points splines, you are allowed to control whether the spline has one segment or multiple segments. Since each spline segment is limited to 25 points (i.e., degree=24), you are allowed to create splines in segments, so that you can create splines with an unlimited number of points.

You will use the default of Multiple Segments.

Creating Splines Creating a Closed Spline If you turn the Closed Curve option on, you can create a closed spline.

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Closed splines connect the first and last points you define.

Creating Splines Controlling the Curve Degree The Curve Degree field lets you control the degree of the spline (only when you are creating a multiple segment spline - for single segment splines, this option is grayed out). As you can see, the default is a cubic spline, i.e. degree=3.

The Spline Display options will be covered in the next section. OK the dialog to accept the settings.

Creating Splines Selecting the Points The Point Constructor dialog is displayed. In this exercise you will be selecting existing points. Choose the Existing Point icon. Select the points at the top of the graphics area (the white points) from left to right. Notice that the control polygon rubber-bands through the points as you select them and the Cue line tells you which point is being specified next.

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If at any time you select the wrong point, choose Back from the MB3 pop-up menu. OK the dialog to specify that you are done selecting points. Choose Yes (use MB2) to confirm that you are done specifying points. The spline is created.

Because a "by poles" spline does not pass through the points you specify, sometimes it can be used to smooth out a curve produced with points that would produce irregular curvature. Refresh the view.

The control polygon display is removed. Now you will check the spline information - you can do this at any time. Choose Information

Object, select the same spline, and OK the dialog.

The poles and the control polygon are highlighted and the Information window displays basic object information (layer, color, etc.) with some spline specific information: degree, number of poles, number of segments, number of each continuity type of knot points, and the spline's polynomial/rational status. Dismiss the Information window.

Creating Splines Creating a Spline Through Points A "Through Points" spline passes through all the points you select (these are the defining points).

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Choose Back twice, to return to the Spline dialog. Choose Through Points. The Spline Through Points dialog is displayed.

Remember you are allowed to control whether the spline has one segment or multiple segments. Since each spline segment is limited to 25 points (i.e., degree=24), you are allowed to create splines in segments, so that you can create splines with an unlimited number of points. OK the Spline Through Points dialog.

Creating Splines Specifying the Points (Using Chain Within Rectangle) You have four different ways you can specify the points that the spline passes through. You can use the Point Constructor or one of the chaining methods shown in the dialog. Choose Chain Within Rectangle.

The Specify Points dialog is displayed. Click MB1 to indicate one corner of the rectangle, then click MB1 again to complete the

381 rectangle so that all of the points in the center of the graphics area (the green points) are trapped within it.

The points within the rectangle are highlighted. The Cue prompts you to select a start point. Select the Start Point and End Point.

The Spline Through Points dialog is displayed.

Creating Splines Applying Constraints to the Defining Points The Cue prompts you to specify constraints, and two more options at the bottom of the dialog become active:

These options let you assign slope and curvature constraints to selected points. You can control the slope of the spline at any of the points. You will define an angular slope constraint at the last point only. Choose Assign Slopes. The Assign Slope dialog is displayed, and the Cue prompts you to select the point you want to assign a slope to.

382 Indicate near the End Point.

The system selects the point nearest to where you indicate. Now the Cue prompts you to specify a slope method. There are 6 different ways you can specify the slope - you will control the slope at this point with an angle. Turn the Angle option on and key in 10 in the Angle field.

OK the dialog to see the vector that displays at the point. OK the dialog two times to create the spline.

Cancel the dialog. Refresh the graphics window.

Creating Splines Spline Display Options The illustration below shows you the various spline display characteristics.

383 You can remove any or all of these spline display objects. Display the Analyze Shape toolbar. Make sure Select General Objects is selected on the Selection toolbar.on, and select the spline you just created. Select the spline you just created. Choose Curve Analysis

Combs icon

or choose Analysis

Curve

Combs.

The curvature comb is displayed.

Creating Splines Curve Analysis - Combs Options Choose the Curve Analysis

Combs Options on the Analyze Shape toolbar.

The Curve Analysis-Combs dialog is displayed.

As you watch the display, change the settings on any of the four sliders. The display of each option is changed as you adjust the sliders. Cancel the Curve Analysis-Combs dialog. Choose the Curvature Analysis-Combs icon off.

on the Analyze Shape toolbar tu turn it

384 You can turn the comb display on and off whenever you wish by selecting the spline and then choosing the Curve Analysis-Combs icon. The curvature analysis display options will be covered in more detail in the Analyzing a Spline section later in this lesson. If you have objects in addition to the spline selected, you may get a Selection dialog displayed as below. You can just ignore this and chose OK.

Creating Splines Creating a Fitted Spline (Using Chain Within Polygon) You can create a fitted spline through a set of points at a given tolerance, using the least squares method.

Choose the Spline icon

or Insert

Curve

Spline.

The Spline dialog is displayed. Choose Fit from the dialog. This time you will select the points by specifying a polygon. Choose Chain Within Polygon. Indicate a series of vertices to enclose the set of points at the bottom of the graphics area (the yellow points).

The first and last points you indicate are automatically connected to create a closed polygon. When you have indicated the last point, OK the dialog.

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Creating Splines Selecting the Specific Points The polygon is closed and all the points inside it are selected. The cue is asking that you select the Start Point. Select the Start Point and End Point.

The Create Spline by Fit dialog is displayed, showing different parameters you can set for the spline.

Creating Splines Defining the Slope with a Vector You will specify the slope at the first and last points. Choose Assign End Slopes. The Cue prompts you to select a point to which the slope assignment will be applied.

386 Indicate near the Start Point.

A series of options shows the different ways you can specify the slope for a selected point. You will define a vector. Toggle the Vector Component option on.

Creating Splines Entering the Values You will enter values so that the vector points to the right and downward. Key in: DXC=1.000 DYC=-1.000 DZC=0, then press Enter.

A vector points from the selected point downward at a 45 degree angle, based on the values you entered.

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Creating Splines Defining the Slope with an Angle Now you will specify the slope at the End Point. This time you will define the slope by an angle. Indicate near the End Point.

Turn the Angle option on and key in -45 in the Angle field, then OK twice.

A direction vector displays at the end point and you are returned to the Create Spline by Fit dialog.

Creating Splines Specifying the Fit Tolerance There are two ways you can specify how close you want the spline to be fitted to the points by a tolerance, or by the number of segments you want the spline to have.

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The By Tolerance fit method is active by default. Key in an allowable error of 0.10 in the Tolerance field. This specifies that the spline will not deviate from any defining point by more than 0.10. If the spline cannot be created to the specified tolerance, an error message is displayed. You can also use Change Weights to change the "weight" of selected points. When a point's weight value is large, the spline will pass through or close to that point. When a point's weight value is zero, the point is essentially ignored. This can be used to eliminate the effect of "bad" points. OK the Create Spline by Fit dialog. The spline is created. A dialog is displayed which shows the maximum error at any particular point and the average error. Notice that the maximum error is less than the 0.10 that you specified.

Refresh the graphics area to remove the control polygon and other temporary display entities.

Close the part file.

Creating Splines Specifying Points from a File The Points From File option lets you specify the points that define a spline using a file containing point definitions. By Poles, Through Points, and Fit allow Points From File.

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Depending on the method of generating your spline, different point formats are used. (For more information about specifying points from a file, see Inputting Points from a File in the Modeling User Manual (in the online or printed documentation).)

Creating a Spline Perpendicular to Planes The Perpendicular to Planes spline creation method lets you create a spline that is perpendicular to each plane in a set.

The maximum number of planes allowed in each set is 100. Open part file crv_splines_2a.prt from the crv directory.

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Start the Modeling application and bring up the Spline dialog. Choose the Modeling icon. Choose the Spline icon. Choose Perpendicular to Planes.

Creating a Spline Perpendicular to Planes Defining an Existing Plane Choose Plane Subfunction.

The Plane dialog is displayed. At this point you can use any of the plane designation options to define your first plane.

391 Choose Existing Plane. Select the plane symbol directly under the WCS.

The Point Constructor is displayed for you to designate the start point on the first plane. Using Control Point or Inferred Point, select at the corner of the plane symbol.

Creating a Spline Perpendicular to Planes Defining a Plane at the WCS Origin You are ready for your second plane designation. Choose Plane Subfunction, then choose Plane of WCS. The second plane is defined, at the XC-YC plane of the WCS and the plane symbol is displayed at the WCS.

Creating a Spline Perpendicular to Planes Defining an Existing Plane

392 You will select another existing plane as the next defining plane for your spline. Choose Plane Subfunction, then choose Existing Plane again. Select the plane symbol directly above the WCS.

The third plane is defined.

Creating a Spline Perpendicular to Planes Defining Planes Through Points and Lines

Now you will define a plane through the three existing points. Choose Plane Subfunction, then choose Three Points. Select the three points in the graphics area.

The fourth plane is defined. You will define the final plane through the two existing lines. Choose Plane Subfunction, then choose Two Lines. Select the two lines in the graphics area.

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Creating a Spline Perpendicular to Planes Creating the Spline You are now ready to generate the spline. OK the dialog to create the spline.

You can see that the spline segments are linear between parallel planes, and circular arcs between non-parallel planes. Reselecting the starting plane as the last plane in the set will not necessarily create a closed spline. Because planes are infinite, the spline is created only to the nearest intersection with the selected plane.

Close all part files.

Analyzing a Spline You can analyze the curvature of splines and detect inflections (reversal of curvature) and peaks. You can display the curvature with a "curvature comb", which is a visual representation of the amount of curvature at various points on your spline. You can also display a graph showing the curvature.

394 Open part file crv_splines_3.prt from the crv subdirectory of the CAST parts directory.

This is a metric part containing one blue spline.

Start the Modleing application. Select the spline. Choose the Curve Analysis - Combs Options icon.

You can also choose Analysis

Curve

Combs Options.

The Curve Analysis-Combs dialog is displayed.

Turn On the Maximum Length option, set it to 93, and then Apply.

(You can also select more than one spline to be analyzed at a time.) The Max Length option defines the maximum length that any of the normals are allowed to reach. Beyond this value, the normals are "capped" with an asterisk. A "curvature comb" is displayed along the spline. Some of the displayed entities were covered earlier in this lesson - now the subject will be covered in more detail.

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Analyzing a Spline The Curvature Comb When curvature distribution is displayed in this way, with normal vectors emanating from the curve, it is called a "curvature comb" because of its appearance. The first option on the Curve Analysis dialog lets you set a Scale, or multiplication factor, for the length of the normals. The Density option sets of number of teeth in the curvature comb, their maximum length, and the percentage of the curve that you want the curvature comb to be displayed on, either from the U-min or U-max direction.

The length of the vector is proportional to the curvature or radius of curvature at that point.

When an individual tooth in the comb exceeds the Maximum Length value, an asterisk is displayed on the end of it; this is called "capping". The tooth is first scaled (using the Scale Factor), then if it exceeds the maximum length, it is "capped".

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U-min and U-max are percentages of the length of the spline. When they are set to 0 and 100, as they are by default, the curvature comb is displayed along the entire spline.

Analyzing a Spline Changing the Curvature Comb Now you will change the values so that fewer teeth are displayed, across a smaller percentage of the curve, and they are no more than 1 inch long. Key in the following values: (Press Enter after entering each value.) Density=50 Max. Length=20

The U-start and U end options are set to 0.0000 and 100.00. This means the teeth of the comb are evenly distributed over the entire spline. Move the U start slider to approximately 25. (Watch the graphics area as you do this.)

397 You can see the beginning of the comb move down the spline. Apply the changes. Now the curvature comb looks as you expect. The comb starts at the 25% point on the spline, and the teeth that are longer than 20 millimeters are "capped" by an asterisk.

Analyzing a Spline The Projection Plane There are three Projection Plane options you can use when analyzing the curvature of a spline.

None - The curve is analyzed 3-dimensionally, that is, it is not projected onto a plane. When you use this option, inflection points are not calculated. Plane of Curve - The spline is analyzed in the plane of the curve (the default). Specified Plane - You specify a plane that the curve is projected onto; then it is analyzed. Work View - The spline is analyzed in the plane of the current Work View. In this case, since this is a planar curve, this option has no effect. You will leave it at the default setting. Cancel the Curves Analysis - Combs dialog.

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Analyzing a Spline Curvature vs. Radius of Curvature You can display either curvature or radius of curvature when the spline is analyzed. This option can be set on the Modeling Preferences dialog. Start the Modeling application. Choose Preferences Free Form tab.

Modeling, and choose the

Curvature and radius of curvature are the inverse of each other. Curvature values are always finite, whereas a radius of curvature value of a straight line is infinitely large. Turn the Radius of Curvature Comb option on.

OK the dialog. As you can see, many of the teeth are longer and capped by an asterisk. The tooth length would be very long in the flatter areas of the spline, since that is where radius of curvature gets very large.

Choose Preferences

Modeling, and return the display to Curvature Comb.

Analyzing a Spline Scale Factor The Scale Factor is applied to the length of the teeth in the curvature comb. You can change the scale factor by using the slider bar or by keying in a new value in the text field.

399 Select the spline. Choose Curve Analysis-Combs Options .

Use the Scale slider control to move the value back and forth. Note the lengths of the comb teeth as you do so.

This capability can help you examine the curvature changes, especially when they are very small or very large, by exaggerating or minimizing them. Cancel the Curves Analysis - Combs dialog.

Analyzing a Spline Inflections and Peaks Inflections (reversals of curvature) are indicated when vectors flip from one side of the curve to the other. If the Inflections option is turned On, an "X" is displayed at each inflection point. Peak points are the points where the curvature is at the local maximum. If the Peaks option is turned On, a small triangle is displayed at each peak point (this may appear as a diamond on some displays).

The Curve Analysis - Inflections display of these.

and Curve Analysis - Peaks icons.

Analyzing a Spline Displaying Information on Curvature Analysis

control

400 You can list all the curvature analysis data to the Information window. Select the spline. Choose Curve Analysis - Output Listing icon choose Analysis Curve Output Listing.

on the Analyze Shpe toolbar or

The Information window gives you detailed information about the vectors: XC, YC, ZC values of the points on the curve. Radius is the radius of curvature at that point. Torsion value is a measure of the angle change as the position deviates from the plane. It will be zero for a planar curve.

Dismiss the Information window. There is another way that you can find information about the spline. You will do this next.

Analyzing a Spline Analyzing the Spline Choose Information

Spline.

Turn the Show Defining Points option on, then OK the dialog.

Select the spline, then OK the dialog.

401 Information about the spline is displayed in the Information window, and special symbols are displayed graphically. The top of the Information window explains what the symbols in the graphics area mean.

Dismiss the Information window and Refresh the view. The Complete listing option gives you much more detailed information about the spline points. Choose Information

Spline, and choose the Complete option.

OK the dialog, select the spline, and OK again. Notice that the spline information is greatly expanded. It includes the continuity and coordinates of each knot point, the weight and coordinates of each pole, and additional information (which may include the coordinates, weight, curvature, tolerance, and/or the number of segments) for each defining point. Dismiss the Information window and close all parts.

Creating a Helical Spline You can create a helical spline by specifying its number of turns, pitch length, turn direction, and orientation, and then specifying a radius method.

402 One way you can use a helix is as the guide geometry for a Tube feature, thereby creating a realistic looking "spring."

Open part file crv_splines_2.prt from the crv directory. Start the Modeling application and bring up the Create Helix dialog. Choose the Modeling icon. Choose Helix icon

.

or choose Insert

Curve

Helix.

The Helix dialog displays.

Creating a Helical Spline Parameters of a Helix Notice that you can specify the number of turns in the helix, the pitch (space between each turn), a method to control the radius, and whether the spiral should have a right or left hand turn.

Number of Turns - The number of helical turns in the spline (must be greater than zero).

403 Pitch - The distance from the start point to the end point of one turn along the helical axis (must be greater than or equal to zero).

Radius Method - You can define the radius as a constant (the Enter Radius option) or with a law function (the Use Law option). For a helix, the value of the law at any point is the helical radius. The illustration above shows a helix defined by a linear law function.

Turn Direction is Right Hand (counterclockwise) or Left Hand (clockwise).

You can use Define Orientation and Point Constructor to define the start point and orientation axis of the helix. If you do not define either of these, the helix will start at the WCS origin and the orientation axis will be the +ZC axis.

Creating a Helical Spline Creating a Helix Using a Linear Law Key in the following values: Number of Turns=4 Pitch=25

Turn the Use Law option on.

404 This dialog displays when you first choose Use Law.

The next section of this lesson covers law curves in much more detail. Choose Linear. The Cue prompts you to define the values for the linear law option. A dialog displays default values.

Key in the following values: Start Value=25 End Value=64

This means that the helical radius will be 25 at the start of the helix and 64 at the end, with a uniform, linear transition from one to the other. OK the dialog.

Creating a Helical Spline Completing the Helix You are returned to the Helix dialog. Notice that the Radius field is grayed out, because you have defined a law to control the radius. You will leave the orientation and start point at the default.

405 If you had selected the wrong law type or wanted to change it from linear to another type, you could choose Use Law again, and the system would give you the option to change the law type, law parameter, or tolerance, from this dialog. You will see this dialog later in this activity.

Apply the Helix dialog. The helix is created. Notice that the +ZC axis is the orientation axis, and the helix starts at the WCS origin.

Cancel the Helix dialog. Use Undo to reject this helical spline. Remember, there are 4 ways to Undo your last action: Choose Edit Undo List from the menu bar and select the feature you wish to undo. Choose the Undo icon on the toolbar. Choose Undo from the MB3 pop-up menu. Key Ctrl-Z.

Creating a Helical Spline Creating a Flat Spiral Helix You can create a flat spiral by using a pitch of zero.

Choose the Helix icon

or choose Insert

Leave Number of Turns set to 4. Key in 0 in the Pitch field.

Curve

Helix.

406 Turn the Use Law option on. Choose Linear. Key in Start Value=25 Key in End Value=64 OK the dialog. Apply the changes. The flat spiral helix is created.

Creating a Helical Spline Creating a Helix Using a Law Curve You will create another helix, this time using a law curve to control the radius. Make layer 5 the work layer and layer 1 invisible. Choose the Layer Settings icon or Format Layer Settings. Key in 5 in the Work field at the top of the dialog, then press Enter. Double-click on layer 1 in the list box to change its status to Invisible. OK the dialog. Fit both views so that you can see all of the geometry.

407 You can see a curve and a line. You will use the line as the helical axis and the curve to guide the radius. Key in 8 in the Number of Turns field. Key in 25 in the Pitch field. NOTE: Even though the Use Law option is still active, you must select it again because you

need to change the law function so that you can use a Law Curve for the next helix. Choose Use Law. Choose Change Law Type. Choose By Law Curve.

Creating a Helical Spline Selecting the Geometry You can select a single curve or a string of contiguous (end-to-end) curves. Select the curve.

OK the dialog to specify that you do not have any more curves in the Law String. Now you must select the Base Line. For a helix, this is the helical axis. If you do not specify one, the current XC axis is used. Select the line. Both arrows must point in the same direction. If they are not, choose Reverse the direction. Otherwise, use OK.

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OK the dialog. The helix is created. Notice that the helical radius follows the shape of the curve.

Close all part files.

Splines Created By Law Law Curve uses a combination of X, Y, and Z components to define a law spline. You can define both two and three-dimensional law splines. Example: A 2-D law spline requires that one plane has a constant value. For example, a Z component defined by a constant law with a value equal to zero results in a curve in the XC-YC plane at Z=0. Similarly, an X component with a constant law value equal to 100 results in a curve in the ZC-YC plane at X=100. You have seven law types available to you to define each of the X, Y, Z components. For more information about the various law types, select the link below.

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More About: Law Types

Here is a brief description of the types of law functions available on this dialog: Linear and Cubic - The function is a linear or cubic rate of change from a start point to an end point. Values Along Spine - Linearand Values long Spine - Cubic; - You define values along a spine curve. By Equation - The function is defined by an expression and an expression variable. By Law Curve - The function is defined by selecting a string of smoothly joined curves and a base line.

Splines Created By Law Creating a Spline by Law Here you will use two of those law types: By Equation: to create a circular spline in X and Y. By Law Curve: to modulate the Z values of the circular spline. Open part file crv_splines_4.prt from the crv directory. This part file contains a spline, which will be used to create a cam-like spline using the law functions.

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Start the Modeling application.

Splines Created By Law Examining Expressions Some special equations have been created in this part file, which you need before you can use the By Law, By Equation options. You will examine these before you create the spline. Choose Tools

Expression.

The Expressions dialog displays. The list box shows the expressions in this part file. To learn more about expressions, see the Expressions CAST Online course. At the top of the Expressions dialog, set the List by option to Creation Order.

You can see the expressions that will be used by the law function.

These expressions are: a=0 - start angle

411 b=360 - end angle n=1 - number of turns r=76 - radius t - an internal system variable that is required with By Equation laws. It defines the parameter space of the function, and its value varies from 0 to 1. s=(1-t)*a+t*b - for calculation of start and end points xt=r*cos(n*s) - X component yt=r*sin(n*s) - Y component OK to dismiss the Expressions dialog.

Splines Created By Law Creating the Spline Choose Insert

Curve

Law Curve.

(You can add the Law Curve icon

to your toolbar by using Tools

Customize.)

The Law Curve dialog displays the law options.

As mentioned, a spline using Law Curve is defined by a set of X, Y, and Z components. You must specify a law for each of these components. Each of the components can be defined by any one of the options on the dialog. You will be using By Equation to specify the X and Y functions. This option is defined by an expression and an expression variable. First you must specify the X component of the law. Choose By Equation. OK the dialog to accept t as the parameter for X, then OK again to accept xt as the function expression for X. Now you must specify the Y component of the law.

412 Choose By Equation again. OK the dialog to accept t as the parameter for Y, then OK again to accept yt as the function expression for Y. Finally, you must specify the Z component of the law. You will use By Law Curve for this purpose, which is defined by selecting a string of smoothly joined curves and a base line. Choose By Law Curve, select the cyan sketch, then OK the dialog.

Splines Created By Law Selecting the Geometry The Cue prompts you to select the Law Base Line. Select the phantom gray line as the base line. If the two arrows are not pointing in the same direction, choose Reverse the direction. Otherwise, use OK.

The Law Curve dialog is displayed. You can use this dialog to specify the base point or orientation. For this exercise, you will just use the current orientation. OK the dialog. The cam-like spline is created, based on the law definitions you have supplied. Fit the view, then Rotate it to see the shape of the spline.

You can see that the shape of the spline, when viewed from the side, follows the shape of the law curve you selected. Restore the view and use Undo to delete the spline you just created.

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Splines Created By Law Orienting Law Curves Next, you will create the same law curve, but this time you will control the orientation of the spline by specifying a coordinate system using datum planes and a datum axis during definition. When creating a law curve based on a coordinate system using datum planes and datum axes, the resulting curve is associative to the planes and axes that positioned them. If the planes or axes are modified, the law curve adjusts accordingly. Make layer 6 Selectable, then Fit the view. Choose Format Layer Settings, double-click on layer 6, then OK the dialog. Choose MB3 Fit.

Choose the Law Curve icon

or choose Insert

Curve

Law Curve.

First you must specify the X component of the law. Choose By Equation. OK the dialog to accept t as the parameter for X, then OK again to accept xt as the function expression for X. Now you must specify the Y component of the law. Choose By Equation again. OK the dialog to accept t as the parameter for Y, then OK again to accept yt as the function expression for Y. Finally, you must specify the Z component of the law. Choose By Law Curve, select the cyan sketch, then OK the dialog. Select the phantom gray line as the Base line.

414 If the two arrows are not pointing in the same direction, choose Reverse the direction otherwise, use OK.

Splines Created By Law Specifying the Coordinate System The Law Curve dialog is displayed. Last time, you accepted the defaults (current WCS). This time you will define a different coordinate system to orient the law curve.

Choose Specify Csys Reference. You are going to use two datum planes and a datum axis to define the coordinate system. The first datum plane selected defines the X-Y placement plane.

The intersection with the second datum plane selected defines the X axis of the local coordinate system.

415 The intersection of the selected datum axis and plane 1 defines the location of the local coordinate system.

Select the datum plane lying in the current XC-ZC plane.

Select the datum plane lying in the current XC-YC plane.

This establishes this datum plane as your horizontal reference plane. Select the datum axis, then OK the dialog.

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OK to dismiss the Law Curve dialog.

Fit the view to see the cam-like spline that you created. Rotate the view to see the way that the spline relates to the coordinate system you defined. Close all part files.

Splines Created By Law Quick Reference: Spline Creation By Law Quick Reference: Creating Spline Circles

X is a By Equation law where xt=r*cos(s). Y is a By Equation law where yt=r*sin(s). Z is a Constant law where the Law Value=0. Constant `r' is used to control the radius. The linear equation: s=(1-t)*a+t*b controls the limits (the start and end angles) of the curve.

417 Constant `a' is the lower limit. Constant `b' is the upper limit. (Although it appears to be a circle/arc, it is not; it is a spline, so the system will not find an arc center for this type of object.)

Splines Created By Law Creating Simple Ellipses Quick Reference: Creating Simple Ellipses X is a By Equation law where xt=r1*cos(s). Y is a By Equation law where yt=r2*sin(s). Z is a Constant law where the Law Value=0. The variables "r1" and "r2" are the minor and major axes, respectively. The linear equation: s=(1-t)*a+t*b controls the limits (the start and end angles) of the curve. Constant `a' is the lower limit. Constant `b' is the upper limit.

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Splines Created By Law Creating Cosine Waves

Quick Reference: Creating Cosine Waves `x' is a Linear law with start value=0 and end value=1. `y' is a By Equation law where yt=a*cos(720*t). `z' is a constant law where the law value=0. Constant `a' is used to control an amplitude of a curve.

Splines Created By Law Creating Involutes of Circles

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Quick Reference: Creating Involutes of a Circle The limits are defined by equation: s=(1-t)*a+t*b. `a' defines the lower limit and is equal to zero. `b' defines the upper limit and is equal to 360. `x' is a By Equation law: xt=r*cos(s)+r*rad(s)*sin(s). `y' is a By Equation law :yt=r*sin(s) - r*rad(s)*cos(s). `z' is a Constant law where the Law Value=0. Constant `r' is used to control the radius. `rad' is the built-in radians conversion function. The `rad' or `deg' must be used with any variables which are specified outside of the built-in trigonometric functions such as Sin or Cos.

Splines Created By Law Creating Simple Parabolas

Quick Reference: Creating Simple Parabolas `x' is a By Equation law where xt=t - 0.5. `y' is a By Equation law where yt=a * xt^2. `z' is a Constant law where the Law Value=0.

420 Constant `a' is used to control an amplitude of a curve.

Splines Created By Law Creating a Uniform Helix

Quick Reference: Creating a Uniform Helix The helix uses the same X and Y laws as the circle in the previous example. However, if you define the Z law as `t', and increase the angle (or number of turns), you can create a helix. X is a By Equation law where xt=r*cos(n*s). Y is a By Equation law where yt=r*sin(n*s). Z is a By Equation law where zt=t. The number of helical turns is `n'. Constant `r' is used to control the radius. The linear equation: s=(1-t)*a+t*b controls the limits (start and end angles) of the curve. Constant `a' is the lower limit; constant `b' is the upper limit.

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Splines Created By Law Creating an Elliptical Helix

Quick Reference: Creating an Elliptical Helix The helical ellipse uses laws similar to the ellipse. However, if you define the Z law as `t' and add `n' to control the number of turns, you can create an elliptical helix. X is a By Equation law where xt=r1*cos(n*s). Y is a By Equation law where yt=r2*sin(n*s). Z is a By Equation law: zt=t. The number of turns is defined by `n'; `r1' controls the major radius; `r2' controls the minor radius. The linear equation: s=(1-t)*a+t*b controls the limits (the start and end angles) of the curve. Constant `a' is the lower limit; `b' is the upper limit.

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Splines Created By Law Creating Catenary Curves Quick Reference: Creating Catenary Curves A catenary curve describes the form assumed by a perfectly flexible, inextensible chain of uniform density hanging from two supports. The general form of equation for a catenary curve is: yt=a*cosh(xt/a) , where cosh = arc cosine. X is a By Equation law where xt=t-0.5. Y is a By Equation law where yt=a*(cosh(xt/a)). Z is a Constant law where the Law Value=0. Constant `a' controls an amplitude of a curve.

Splines Created By Law Spline Types

Quick Reference Chart: Spline Types This chart summarizes the advantages and disadvantages of different spline types. Advantages

Disadvantages

423 Single Segment Spline Useful for low number of points

Number of points fixes the degree of the curve

Can increase degree to get more control vertices (poles) for editing

Can cause problems if used with a high number of points Moving one control point moves every point on the curves (except first and last)

Multiple Segment Spline User-specified degree (between 1 and 24) Cannot decrease the degree Slope control allowed for all points Degree independent of number of points Each control point only affects the portion of the curve near it Can create open and closed curves Fit Spline Keeps amount of data to a minimum

Constructed using approximation - does not pass exactly through points

Produces smooth curves Slope control for first and last points Helix Easy creation of B-curve to approximate a Indirect control over number of points and helix segments Can edit shape by changing parameters Can control radii by law By Law Ability to control splines by expressions

Creating an Ellipse You can create ellipses by specifying the major and minor diameter values and an orientation angle. You can also use the start and end angles to create a partial ellipse. Open part file crv_conics_1.prt from the crv sub-directory of the CAST parts directory. Start the Modeling application and start the ellipse creation process. Choose the Modeling icon

or choose Application

Modeling.

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Choose the Ellipse icon

or choose Insert

Curve

Ellipse.

The Point Constructor dialog is displayed. You will use it to define the center of the ellipse by indicating a point. Indicate a point a little to the left of the WCS. These are some of the parameters you must define for an ellipse.

An ellipse is created in a counter-clockwise direction, beginning at the Start Angle and stopping at the End Angle. For a full ellipse, the Start Angle is 0 and the End Angle is 360.

Remember that an angle of 0 is on the Major axis. In addition, you can rotate the entire ellipse. When the Rotation Angle is 0, the Major axis is parallel to the XC axis.

Key in the following values:

425 Semimajor = 25 Semiminor = 12 Start Angle = 0 End Angle = 360 Rotation Angle = 0 OK the dialog. An ellipse is created and the Ellipse dialog is dialog is displayed again, so that you can create another ellipse with different paramters (if you wish), or choose Back and (to the Point Constructor dialog) and choose a new location for an ellipse. Create as many ellipses as you like, using these steps and experimenting with different values.

Creating Parabolas & Hyperbolas Parabolas and hyperbolas are standard conic curves that you can create in Unigraphics NX. (You should still be in the crv_conics_1.prt part file and in the Modeling application.)

Choose the Parabola icon

or choose Insert

Curve

Parabola.

At any time, if the graphics area becomes too crowded, you can use Edit Delete to delete some or all of the objects you have created, or change to a different layer.

Creating Parabolas & Hyperbolas Creating a Parabola The Point Constructor dialog is displayed. First you must specify the vertex of the parabola. Indicate a point anywhere in the graphics area. These are some of the parameters you must define for a parabola.

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Key in these values in the dialog: Focal Length = 6 Minimum DY = -25 Maximum DY = 25 Rot Angle = 0 OK the dialog. A parabola is created and the Point Constructor dialog is displayed again, so that you can create another parabola. Create as many parabolas as you like, using these steps.

Creating Parabolas & Hyperbolas Creating a Hyperbola By definition, a hyperbola contains two curves on either side of its center. In Unigraphics NX, only one of these curves is constructed.

Choose the Hyperbola icon

or choose Insert

Curve

Hyperbola.

The Point Constructor dialog is displayed. Indicate a point anywhere in the graphics area. These are some of the parameters you must define for a hyperbola. The point you just indicated is "F", the center.

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Key in the following values: Semitransverse = 12 Semiconjugate = 12 Minimum DY = -25 Maximum DY = 25 Rotation Angle = 0 OK the dialog. Fit the view, if necessary. A hyperbola is created and the Point Constructor dialog is displayed again, so that you can create another hyperbola. Create as many hyperbolas as you like, using these steps.

Creating General Conics You can use the General Conic option to create a curve using either one of the various loft conic methods or the general conic equation. The resulting conic is either a circle, an ellipse, a parabola, or a hyperbola; depending upon the mathematical results of the input data. This option is more flexible than the ellipse, parabola, and hyperbola options, since it allows several different methods for defining the curve by selecting geometry. (You should still be in the crv_conics_1.prt part file and in the Modeling application.)

Choose the General Conic icon

or choose Insert

Curve

General Conic.

The General Conic dialog displays the methods you can use to define a general conic.

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For more information about the various methods of defining a general conic, select the link below.

More About: General Conic Types

Here is a brief summary of the methods of creating general conics. 5 Pts - Defines a conic curve using 5 points. This method is illustrated during this exercise. 4 Pts, 1 Slp - Defines a conic curve using 4 points and the slope of the curve at the first point. 3 Pts, 2 Slp - Defines a conic curve using 3 points and the slope of the curve at the first point

and last point. 3 Pts, Anchor - Defines a conic curve using 3 points and an "anchor" point, which is the

intersection of the two end tangent vectors. This method is illustrated during this exercise. 2 Pts, Anchor, Rho - Defines a conic curve using 2 points, an "anchor" point, and a Rho

value. Coefficients - Defines a conic curve using the coefficients of the conic equation. 2 Pts, 2 Slp, Rho - Defines a conic curve using 2 points, the starting and ending slopes, and a

Rho value.

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Creating General Conics Creating a Conic Through 5 Points First, you will switch to another layer.

Choose the Layer Settings icon

or choose Format

Layer Settings.

Choose Fit All Before Displaying to turn the option on.

Make layer 10 the work layer and layer 5 Invisible, then OK the dialog. The graphics area should look like this:

Choose the 5 Points option. The Point Constructor dialog is displayed. Select the points in a counter-clockwise direction as shown.

As soon as the fifth point is selected, the conic is created.

430 Choose Information

Object.

Select the conic you just created, then use OK. The Information window shows you that the conic is a hyperbola. When the general conic is a circle, ellipse, or parabola, it goes through all 5 points, starting at the first and going to the last. If the conic is a hyperbola, the system does not necessarily connect the first and fifth points. Even though points on both branches are defined, only one of the two branches is created.

Dismiss the Information window.

Creating General Conics Creating a Conic Using 3 Points and an Anchor Before you continue, change to another layer. Make layer 11 the Work Layer and layer 10 Invisible. Choose the Layer Settings icon or choose Format Select layer 11 in the list box, then choose Make Work. Double-click on layer 10 to change its status to Invisible. OK the dialog.

The graphics area should look like this:

Layer Settings.

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Choose the General Conic icon Points, Anchor.

or choose Insert

Curve

General Conic

3

The Point Constructor dialog is displayed. To create this conic, you will select some existing points. Choose the Existing Point icon. Select the points as shown below.

As soon as the anchor point is selected, the conic is created. You can see that the tangents on both sides go through the anchor point.

Close all part files.

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Additional Curve Options In this lesson, you will learn how to create curves using several different methods, and how to change curves by joining them together, bridging the gap between curves, and simplifying curves.

Creating Chamfers There are two methods for creating chamfers: Simple Chamfer User-Defined Chamfer A simple chamfer has equal offsets on both of the two selected lines. For example, in a situation where the two coplanar lines are at a 90° orientation to each other (as shown below), the simple chamfer creates a 45° bevel between two lines.

433 A user-defined chamfer can create a bevel using arcs, splines, and conics, as well as lines. You can also specify an offset and an angle or two different offsets to control the size of the bevel. Open part file crv_chamfer_1.prt from the crv subdirectory.

This is a metric part containing several curves. Start the Modeling application and bring up the Chamfer dialog. Choose the Modeling icon

or choose Application

Choose the Curve Chamfer icon

or choose Insert

Modeling. Curve

Chamfer.

Creating Chamfers Creating a Simple Chamfer A simple chamfer creates a bevel between two coplanar intersecting lines (if the lines are perpendicular, the bevel is at 45°) at a given offset. You cannot use curves other than lines, and you must be able to get both lines into the selection ball at the same time. If either of these two conditions cannot be met, use the User Defined Chamfer option instead. Choose Simple Chamfer. Key in 32 in the Offset field, then OK the dialog. Move the cursor so that both lines are inside the selection ball as shown below, then click MB1.

434

The chamfer is created. Select the opposite corner in the same way.

The second chamfer is created. Each time you select a pair of lines, another chamfer is created.

You can choose Undo in the dialog to restore the lines if needed.

Creating Chamfers Creating a User-Defined Chamfer with One Offset and an Angle A user-defined chamfer can create a bevel using lines, arcs, splines, and conics. It also gives you complete control over the size, angle, and trimming of the chamfer. You will create a user-defined chamfer at an offset with a given angle. Choose Back twice to return to the Chamfer dialog. Choose User-Defined Chamfer. A dialog is displayed showing you the trimming options that are available. Choose Automatic Trim.

435 Another dialog is displayed. You can use it to create a chamfer by specifying one offset and an angle. The offset value is measured from the first curve you select, along the second curve. The angle is measured from the second curve. Key in 64 in the Offset field and 30 in the Angle field, then OK the dialog. Select the line, then the arc.

Indicate inside the chamfer.

The chamfer is created.

Notice that the offset dimension (64) was measured along the arc, since it was the second object you selected. Likewise, the 30 degree angle was measured from a line through the chamfer break point and tangent to the arc.

436

Creating Chamfers Creating a User-Defined Chamfer with Two Offsets This time you will create a chamfer between the two yellow lines, using two different offset values.

Choose Back. You are still working with a user-defined chamfer and in automatic trim. Choose Offset Values. Now, instead of an offset and angle, you must specify two offsets. Key in 64 for Offset 1 and 38 for Offset 2, then OK the dialog. Select the curves for the chamfer.

Indicate inside the chamfer.

The chamfer is created. The two offset values are measured along the respective selected curves.

437

Creating Chamfers Creating the Opposite Chamfer Now you will undo the chamfer and reselect the lines in the opposite order to see how this affects the resulting chamfer. Cancel the dialogs. Choose Undo from the dialog. The lines are restored to their original appearance. Using the same curves and function, create another chamfer, but select the curves in the opposite order.

Indicate inside the chamfer. This time the chamfer is created in the opposite direction.

Creating Rectangles and Polygons First you will open a new part file and create a rectangle. Rectangles are created in the XCYC, YC-ZC or XC-ZC plane. Start a new part file, using Millimeters units and any name you wish (you will not save this part). Start the Modeling application.

438

Choose the Modeling icon

Choose the Rectangle icon

or choose Application

orInsert

Curve

Modeling.

Rectangle.

The Point Constructor dialog is displayed, with the Infer icon active. A rectangle is created by defining two corner points. Indicate a location in the graphics area. Notice that, even though the Infer icon is active, a cursor location was inferred. This is what occurs when you click MB1 in the graphics area and there is nothing inside the selection ball, when using Infer or Control Point. If you move the cursor around, you can see the rectangle "rubber-banding" from the point you defined. Indicate another location. The rectangle is created. Cancel the Point Constructor dialog. Undo the rectangle you created. Choose Edit Undo List Use MB3 Undo -ORUse Ctrl-Z.

Rectangle

-OR-

The entire rectangle is deleted. This is the only time that the rectangle is treated as a single object. For all other purposes, the rectangle is actually four independent lines.

Creating Rectangles and Polygons Creating Another Rectangle Choose the Rectangle icon

or Insert

Indicate a location in the graphics area. Indicate another location. Cancel the Point Constructor dialog. Choose Edit

Delete.

Select any of the lines in the rectangle. Notice that only the single line is highlighted.

Curve

Rectangle.

439 OK the dialog. The selected line is deleted, but the other three lines remain.

Creating Rectangles and Polygons Creating Polygons Continue with the same part file. You can change to a different layer, or use MB3 you need more room in the graphics area.

Choose the Polygon icon

or Insert

Curve

Pan if

Polygon.

You must specify how many sides there are in the polygon. OK the dialog to accept the default of 6 sides (a hexagon). There are three methods you can use to define the size of a polygon:

Creating Rectangles and Polygons Creating the Hexagon Choose Inscribed Radius. You must define the radius of the inscribed circle, and an orientation angle. The angle determines the rotation of the polygon:

Key in a radius of 25 and angle of 0, and OK the dialog.

440 The Point Constructor dialog is displayed. The final step is to define the center of the polygon. Indicate a point to define the center point. The polygon is displayed. At this point, you could define additional points and an identical polygon would be created at each one. Choose Back. Key in 30 in the Orientation Angle field, then OK the dialog. Indicate a point. Another polygon is created, this time rotated by 30 degrees. Cancel the dialog.

Creating Offset Curves You can use the Offset icon to offset one or more planar curves. If you select multiple curves, they must be contiguous (end-to-end) and coplanar. Open part file crv_offset_1.prt from the crv subdirectory.

This is, again, a metric part. Start the Modeling application. Choose the Modeling icon

Choose the Offset Curve icon

or choose Application

or Insert

Curve Operation

Modeling.

Offset.

441 The cue prompts you to select the string of curves to be offset. Select the two vertical lines and the spline.

OK the dialog to indicate that you have selected all the objects you want to offset. If you select a single line to offset, you must specify an additional point to define the plane of the offset. The Offset Curves dialog is displayed. A vector is also displayed. It indicates the direction in which the offset curves will be created. (Your display may look different, depending on the order in which you selected the curves.)

If the vector is NOT pointing away from the selected curves (as it is above), choose Reverse Direction. The vector should be pointing out, away from the curves, as shown below.

Creating Offset Curves The Offset Method There are four offset methods available:

442 Distance - The offset curves are created at a constant distance, in the same plane as the original curves. Draft - The offset curves are created in a plane parallel to the plane of the original curves and offset from it by the Draft Height. The distance between the original curves and the offset curves is determined by the Draft Height and Draft Angle values. Law Control - The offset is controlled using the Law Subfunction. The offset in this case, is in the plane of the selected curves. 3D Axial - The offset is along a specified vector, and can be made from 3 curves. First you will use the default Distance option to create offset curves at a constant distance.

Notice that the Draft Height and Draft Angle fields are grayed out. They are only available when you are using the Draft offset method.

Creating Offset Curves Relating the Offset Curves to the Original Curves Notice that the Associative Output option is active.

This means that the offset curves will be associative to the original curves. Any subsequent change to the original curves will be reflected in the offset curves. In addition, notice that the Input Curves option is set to Retain. Display the Input Curves options.

443

This means that, after the offset curves are created, the original curves will still be displayed. The Delete and Replace options are greyed out. When you are in Associative Output mode, the only other available option is Blank. If you use the Blank option, the original curves will be blanked after the offset curves are created. Turn the Associative Output option off.

Display the Input Curves options again.

This time, because Associative Output mode is off, you have two additional options. You can choose to delete the original curves after the offset curves are created, or you can replace the original curves with the offset curves. Turn the Associative Output option back on.

Creating Offset Curves The Trim Method Notice that the default Trim method is Extended Tangents. First you will see what happens when you have no trimming.

444 Change the Trim option to None.

Key in 12 in the Distance field and Apply. The curves are offset. Notice that no trimming took place on the new curves. If you tried to do another offset, it would not work, because the selected curves are no longer contiguous.

The accuracy of the offset from a spline or conic is determined by the Approx Tolerance value. Choose Undo from the MB3 pop-up or use Undo List on the Edit pull-down menu. The offset curves are removed.

Creating Offset Curves Trimming by Extending the Curve Tangents Now you will see what happens with the trimming turned on.

Choose the Offset Curve icon

or Insert

Curve Operation

Offset.

Select the two vertical lines and the spline again. OK the dialog. If the vector is not pointing away from the selected curves, choose Reverse Direction.

445 Change the Trim option back to Extended Tangents.

Apply again. This time the offset curves are extended to their intersections: The lines are simply extended - there is still just one line on each side. The spline has extension lines added on each end. They are tangent to the spline at its endpoints.

Notice also that the direction vector has moved to the new curves. You can continue to use Apply to create additional offsets. Apply again. Another set of offset curves is created, and the direction vector moves to this newest set of curves.

You can also use the Number of Copies field to specify multiple offsets.

Creating Offset Curves Trimming by Creating a Fillet You can also trim the extended curves using a fillet.

446 Change the Trim option to Fillet.

Apply again. This time, instead of the offset curves being extended to their intersection, a fillet is created between them. The radius of this first fillet is equal to the offset Distance value.

Creating Offset Curves Offsetting Curves Using Law Control Choose Law Control as the Offset by option.

The Law Subfunction menu is displayed. This function will be demonstrated using a simple linear law, but you can use any of the usual Unigraphics NX law methods. Choose Linear. Change the Start Value to 12 and the End Value to 25. OK, then Apply. Now the offset starts at a distance of 12 and ends at a distance of 25 from the string of curves.

447

Creating Offset Curves Offset Curve Associativity You will move one of the spline's defining points to change the shape of the spline. You will see how this affects the associative offset curves. Choose the Edit Curve Parameters icon

or Edit

Curve

Select the original spline.

The Edit Spline dialog is displayed. Choose Edit Point. The spline's defining points are displayed. Make sure the Move Point option is on in the Edit Point dialog.

Indicate near the second point from the left.

The nearest spline defining point is selected.

Parameters.

448 Indicate a new position above the selected point, approximately as shown here.

A temporary display of the new spline is highlighted.

Cancel the dialog. All splines offset from the original are updated, because they are associated to the original.

Creating Offset Curves Editing Offset Curve Parameters Besides editing the original curves, you can also change offset curves by editing the offset parameters.

449

Choose the Edit Curve Parameters icon

or Edit

Curve

Parameters.

Select anywhere on the outer-most set of offset curves. The entire set of curves is selected and the Edit Offset Curves dialog is displayed.

You can also display this dialog by choosing Edit Feature Edit Parameters, then selecting an offset curve or the OFFSET_CURVE feature from the Feature Selection dialog. As you can see, the Edit Offset Curves dialog looks almost the same as the dialog you used to create the offset curves originally. One new option is Redefine String, which you can use to add or remove curves from the string of original curves. You will change the offset method from Law Control to Distance. Change the Offset by option to Distance. Enter 12 in the Distance field. OK twice. The offset curves are changed. Now the final string of offset curves is at a constant distance from the previous string of curves.

450

Creating Offset Curves Rough Offset This option is more robust in handling such things as self-intersections. Open the part file crv_offset_2.prt from the crv directory and start the Modeling application.

First you are going to create an offset curve inward without using Rough Offset. This will produce a self-intersecting set of curves. You will then use Rough Offset and compare the results.

Creating Offset Curves Creating the Offset Choose the Offset Curve icon

or choose Insert

Curve Operation

Offset.

Select all four splines and OK the dialog. Set Offset by to Distance, and enter a distance of 2.0.

Make sure Associative Output is on, Rough Offset is off, and Input Curves is set to Retain.

Make sure the direction arrow is pointing inwards (Use Reverse Direction if needed). and then OK the dialog. Notice the self-intersection in the offset curves.

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You would rather have the system ignore this degree of accuracy, and simply stop the curves where they intersect. Rough Offset will do that.

Creating Offset Curves Creating a Rough Offset Undo the offset feature you just created.

Choose the Offset Curve icon

or choose Insert

Curve Operation

Offset.

Select all four splines and OK the dialog. Set Offset by to Distance, and enter a distance of 2.0.

Make sure Associative Output is on, Rough Offset is on, and Input Curves is set to Retain.

Make sure the direction arrow is pointing inwards (Use Reverse Direction if needed). and then OK the dialog. Notice how the self-intersection was handled.

452 Close the part file.

Creating Offset Curves 3D Axial Offset This is an offset method that allows offsetting 3D curves along a specified axis. Open the part file crv_offset_3.prt from the crv directory and start the Modeling application.

What you see is a Helix and a associative Bridging Curve. You are going to offset them in a specified direction, and then edit the parent helix.

Choose the Offset Curve icon

or choose Insert

Curve Operation

Offset.

Select the two curves and OK the dialog. Choose Axis Vector

Vector Constructor.

Set the I J K components as below:

OK the Vector Constructor dialog.

Creating Offset Curves Completing the Offset Offset by will automatically be set to 3D Axial, since you selected three-dimensional curves.

Set the 3D Offset Value to 20.0.

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Make sure Associative Output is on. OK the dialog.

Creating Offset Curves Editing the Offset With Select Features active, double-click (with MB1) on the helix, to get the Edit Helix dialog. Change the radius to 22.0.

Apply the dialog.

Leave the part file open.

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Creating Offset Curves Editing the Offset Direction You now want to make the offset direction vertical (parallel to the ZC axis). Choose the Inferred Vector icon on the dialog, and select +ZC.

OK the dialog.

Cancel the dialogs and Close the part file.

Projecting Points and Curves You can project points, lines, arcs, conics, and splines onto faces and planes. You can project these curves in a number of different ways, and the projected curves can be associative to the original curves. Open part file crv_project_1.prt from the crv subdirectory. You see a free form feature (a sheet body, with one face). Above it, on the XC-YC plane, there is a circle and a spline. You will project these objects down onto the sheet body.

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Start the Modeling application. Choose the Modeling icon.

Choose the Project icon

or Insert

.

Curve Operation

Project.

Projecting Points and Curves Projecting a Curve Along a Vector The Project Curve dialog is displayed.

Notice that you have three different Copy Method options. This option determines what happens to the original curves.

Associate - The original curves are retained, and projected copies are created. The projected curves remain associated to the originals. (This is the default.) Copy - The original curves are retained, and projected copies are created. The projected curves are not associated to the originals. Move - The curves are projected, and the original curves are not retained. For this exercise, you will not retain the original curve.

456 Choose Move. You can project the curve in a number of different ways, using the Direction Method menu:

If you use the Toward a Point or Toward a Line method, and the point or line is later moved, the projected curves are updated accordingly. Change the Direction Method to Along Vector. The Vector Constructor dialog is displayed. Choose ZC Axis as the projection vector, and then choose Cycle Vector Direction (so it is pointing down). OK the dialog. Now you must select the geometry you want to project. Select the spline.

This is the only curve you want to project. OK the dialog. The cue prompts you to select faces and planes. Select the face, and then choose Apply.

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The spline is projected. Notice that the color of the projected spline is magenta (the color preference setting for new objects). Also notice that the original spline has been deleted.

As you can see (especially if you rotate the view), the projected spline is trimmed at the edges of the face. When a curve is projected onto a face, it is trimmed at the edges of the face and at any holes.

Projecting Points and Curves Projecting a Curve and Retaining the Original Curve This time you will project the circle onto the face, but maintain the original. You should still have the Project Curves dialog up if not, bring it up. Choose the Project icon

or Insert

Curve Operation

Project.

This time you are going to retain the original curve. The projected curve and the original will be associated. Make sure the Associate option is on. Select the circle, then OK the dialog.

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Select the face. Change the Direction Method to Along Vector. Choose ZC Axis, and then choose Cycle Vector Direction, and OK the dialog. OK the dialog again. The Circle is projected onto the face.

Because you used the Associate copy method, the original curve has been retained and remains associated to the projected curve. Bring up the Edit Curve Parameters dialog and change the radius of the original circle to 30. Choose the Edit Curve Parameters icon or Edit Curve Parameters. Select the original (green) circle. (Make sure you select the edge of the circle, not its center.) In the dialog bar, change the radius to 30 and press Enter. OK to dismiss the Edit Curve Parameters dialog. The projected curve is automatically updated when the Edit Curve dialog is removed.

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Projecting Points and Curves Projecting Along Face Normals This time, you will project the circle again, but along the face normals. First, you will change the default object color, so that you can see the difference between the two curves projected from the circle. Change the new object preference color to White. Choose Preferences Object. Choose the Color option. With MB1 select the color white from one of the layers of the cube or from the Quick Access Colors section, then OK the dialog.

Now you can project the circle onto the face.

Choose the Project icon

or Insert

Curve Operation

Project.

Make sure the Associate option is on. Set the Direction Method to Along Face Normals if necessary. Select the circle, then OK the dialog. (Make sure you select the green circle, not the magenta curve that was created with the previous projection.)

Select the face, then OK the dialog. The circle is projected onto the face along the face normals. You can see that this projected curve is different than when you projected along the ZC axis.

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Projecting Points and Curves Editing Projected Curves as Features Associated projected curves can be edited as features in some cases.

Choose the Edit Feature Parameters icon

or Edit

Feature

Parameters.

Notice the "CPROJ" features in the Edit Parameters dialog. These are the curve projection features you just created. This feature type is only created when you use the Associate copy method.

Double-click on the first CPROJ feature. The Edit Projection Curve Feature dialog is displayed. It looks very much like the dialog you used to create the feature. NOTE: You can also display this dialog by choosing the Edit Curve icon on the Create Curve

dialog, then selecting the projected curve. You can also double-click on the feature itself on the graphics screen. Change the Direction Method to Angle to Vector. Choose ZC Axis, and then choose Cycle Vector Direction. OK the dialog. Enter 20 in the Angle field, then OK the dialogs until the part updates. The projected curve is changed.

461 You can perform other Edit Feature operations on curve projection features also - reorder, delete, suppress, and unsuppress.

Combine Curve Projections You can also create a curve by projecting two other strings of curves and combining the two projections. Open part file crv_project_2.prt from the crv subdirectory of the CAST parts directory. This metric part contains an arc in one plane and a string of curves in another plane. These curves need to be projected and combined.

Start the Modeling application. Choose the Modeling icon.

Choose the Combined Projection icon Combined Projection.

.

or choose Insert

The Combined Curve Projection dialog is displayed.

Notice the Associative Output option.

Curve Operation

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If you turn this option off, the resulting curve will not be associated to the original curves. If it is on (as it is here - "on" is the default), any change to the original curves will be reflected in the combined curve.

Combine Curve Projections Selecting the Geometry You must select the two strings of curves to be combined, then specify the projection vector for each string.

Notice that the First Curve String selection step is selected. Select the line and arc on the upper plane, confirm this on the QuickPick dialog if necessary, then use MB2 to specify that you are done defining the first string.

Both the line and the arc in the string are selected at once because they are both part of a single sketch. Selection assumes that you want to use all components of this sketch feature. Now the Second Curve String selection step is selected.

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Select the arc on the lower plane and press MB2.

Combine Curve Projections Specifying the Projection Direction Notice that now the Third Projection Vector selection step is selected. You can define a projection direction for one string or the other, or both.

You can also see that the default projection direction is normal to the plane of the curves, and you can see the vector describing this displayed in the graphics area.

464 Since you want to project both curve strings normal to the plane of the curves, you do not need to specify a direction for either string of curves. NOTE: The projection direction is associative - you can change it later with Edit Curve or

Edit Feature. OK the dialog to create the combined projected string.

If you use Info and a spline.

Object on these new curves, you will see that the system created an ellipse

Join, Bridge, and Simplify These three options act on curves in the following ways: Join creates a spline from a chain of continuous curves. Bridge creates a tangent or curvature continuous spline between two given curves. Simplify creates a string of best fit lines and arcs from a string of chosen curves.

Joining Curves If you have a chain contiguous curves, you can use Join to turn them into a single spline. Joining curves is a convenient way to create a spline. Once an object is converted to a spline, you have more freedom to edit its shape.

465 Open part file crv_join_1.prt from the crv subdirectory. The part contains 3 green lines and 2 cyan arcs. The lines and arcs are different colors so you can see that they are all separate objects.

Start the Modeling application. Choose the Modeling icon.

Choose the Join icon

or Insert

.

Curve Operation

Join.

First, you must select the curves to be joined. Choose Chain Curves. Using chaining is a good way to make sure the curves are contiguous. If they are not, Join will not work! The cue prompts you to select the chain start. Select the first curve (to the right of the midpoint), then select the last curve (to the left of the midpoint).

All the curves should now be highlighted. OK twice. The Join Curves dialog is displayed.

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Joining Curves Controlling the Status of the Original Curves The Input Curves option controls what happens to the original curves after the spline is created. This option can be set to: Retain - The original curves are not changed (the default). Blank - The original curves are blanked. This lets you use Unblank to redisplay them later if you wish. Delete - The original curves are deleted from the part. Replace - The original curves are replaced by the joined curve. NOTE: The Delete and Replace options are not available if you are creating an associative

joined curve. You will keep the original curves, but remove them from the screen by blanking them. Change the Input Curves option to Blank.

Joining Curves Controlling the Resulting Curve Type

The Resulting Curve Type area lets you choose which type of spline you want to create from the selected curves: Polynomial - a spline that approximates the original chain (to a tolerance) General Spline - a spline that exactly represents the original chain of curves

467 Where an approximate representation is acceptable, a polynomial cubic is preferred over a general spline. Polynomial cubic (degree of 3) curves are easier to transfer to other systems than higher degree curves, and they are easier to edit. Make sure the Resulting Curve Type is set to Polynomial. OK the dialog to accept. Notice that the curve is now all one color - the lines and arcs have been replaced by a single spline.

You can look at the blanked original curves and see that they still exist. Choose Edit

Blank

Reverse Blank All.

The original curves are displayed.

Creating a Bridge Curve The Bridge option creates a curve between two selected curves to bridge the gap between them. Open part file crv_bridge_1.prt from the crv subdirectory. The part is composed of 2 splines.

468 Start the Modeling application. Choose the Modeling icon.

Choose the Bridge Curve icon

.

or choose Insert

Curve Operation

Bridge.

The Bridge Curve dialog is displayed.

Below the selection steps, there are two Continuity Methods.

The Continuity Method options let you match the new curve to the existing curves in one of the following ways: Tangent - A cubic Bezier curve is created. It matches the tangents at the corresponding points of the selected curves. Curvature - A quintic Bezier curve is created. It matches the tangents and the curvatures at the corresponding points of the selected curves. The number of selection steps at the top of the dialog depends on the Continuity Method chosen.

First Curve Second Curve Reference Shape Curve- only for tangent continuity At the bottom of the dialog, you can choose to create Associative Output.

469

If this is chosen, the system will create a BRIDGE_CURVE feature. This will associate the bridge curve with the selected input curves - if they change, the bridge curve will update. Bridge Curve features can be edited using Edit Feature Parameters.

Creating a Bridge Curve Matching Tangents Make sure the Tangent Continuity Method option is on. Select the first curve near the top end. Select the second curve near the top end.

The gap is bridged with a new spline curve. This is a temporary display. If you like the curve, you can choose Apply and the curve will be created. Do NOT choose Apply yet.

Creating a Bridge Curve Changing the Bridge Curve

Now you are going to change the start and end locations of the curve. Choose the First Curve selection step.

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The first curve you selected should highlight and the Start/End Location slider becomes available.

Using the slider, set the Start/End Location to 0.00. Notice how the end point of the bridge curve slides along the first curve, with the slope changing to maintain tangency. Choose the Second Curve selection step.

The second curve you selected should highlight. Using the slider, set the Start/End Location to 100.00. Again, notice how the end point of the bridge curve slides along the second curve with the slope changing to maintain tangency. Now the bridge curve is at the opposite end of both the selected curves.

You can also reverse the direction of the tangent vector on the bridge curve.

471 Choose Reverse Direction. (This affects the end slope of curve 2.) Choose the first selection step and the first curve will again highlight. Choose Reverse Direction again. The direction of the curve is reversed at both ends of the bridge.

As you can see, you have a great deal of flexibility in controlling how the bridging curve will connect two curves.

Creating a Bridge Curve Shape Control

In the middle portion of the dialog, there is a Shape Control area. You can control the shape of the bridge curve at either its ends, or in the middle. If you choose End Points, the dialog appears as below:

Move the First Curve slider bar left and right, and notice the affect on the bridge curve. Try the same thing with the Second Curve slider bar. OK twice when you are done adjusting the shape of the curve.

472 Choose MB3

Undo to delete the curve.

Creating a Bridge Curve Matching Curvatures

You will create another bridge curve, this time using the Curvature Continuity method. Choose Insert

Curve Operation

Bridge.

Choose Curvature Continuity Method. Select the original curves again, this time in the opposite order.

The new bridge curve is temporarily created.

Choose the Peak Point Shape Control option.

The options now displayed in the middle of the dialog let you change the shape of your curve at its peak point. Notice that Bridge Depth and Bridge Skew are both set to 50% by default.

473

Slide the Bridge Depth and Bridge Skew buttons back and forth to observe the effect of changing these options. When you have the shape you want, OK the dialog. Close the part file.

Simplifying a Spline You can use Simplify to approximate a spline by converting it into arcs and lines. It is the "opposite" of Join. Open part file crv_simplify_1.prt from the crv subdirectory. This metric part contains one spline, which is on layer 10. You will create the new curves on layer 1.

Start the Modeling application. Choose the Modeling icon.

.

The Distance Tolerance has been changed so that the new curves are not too close to the shape of the original curve. This will help you see the effects of this option more clearly. (Normally this option is set to a small value, 0.0254 by default in a new metric part.) You must set the Distance Tolerance before you start the procedure.

474 Choose Preferences

Modeling.

Make sure the General tab is selected. Note that the Distance Tolerance is set to 1.000.

OK the dialog. Choose the Simplify Curve icon

or choose Insert

Curve Operation

Simplify.

You must specify what to do with the selected curve once it has been simplified. These options work the same as they do with Join. Choose Maintain.

The Select curves to approximate dialog is displayed. Select the spline and OK the dialog. The new curves (in magenta) are created to approximate the shape of the spline. Because you set the Distance Tolerance to .1.0 (an unnaturally large tolerance!), you can see gaps between the spline and the new curves.

Use the Layer Settings icon to make layer 10 Invisible, then use Information Object to examine the curves the system created. The shape of the spline has been approximated by 10 contiguous arcs.

475

Close the Information window when you are finished.

Wrapping and Unwrapping Curves You can use the Wrap/Unwrap option to wrap curves from a plane onto a cylindrical or conical face or unwrap curves from a face onto a plane or face. The plane must be tangent to the cylindrical or conical face. The resulting curves are 3rd degree B-splines and are associative to the input curves, the defining face and the defining plane. Wrap/Unwrap Terminology

Open part file crv_wrap_1.prt from the crv subdirectory of the CAST parts directory. This metric part consists of one large tube that is intersected by a smaller tube at a 45 degree angle, and a datum plane that is tangent to the back face of the large cylinder. Also, curves have been created at the intersection of the outer faces of the two bodies.

476

Start the Modeling application. Choose the Modeling icon.

.

Wrapping and Unwrapping Curves The Wrap/Unwrap Dialog

Choose the Wrap/Unwrap icon

or Insert

Curve Operation

Wrap/Unwrap.

The Wrap/Unwrap Curve dialog is displayed.

There are three Selection Steps for wrapping or unwrapping curves: Wrap Face - to specify the face you are wrapping curves to or unwrapping curves from. Wrap Plane - to specify the plane that holds the curves that are to be wrapped or the curves that have been unwrapped. Curves - to specify the curves that are to be wrapped or unwrapped.

477

Wrapping and Unwrapping Curves Unwrapping Curves You are going to unwrap the large tube edges to the datum plane. Turn On the Unwrap option.

You are prompted to select the cylindrical / conical wrap face(s). Select the outer face of the large cylinder.

At this point, you have the ability to select more wrap faces. Use MB2 to specify that you are done selecting wrap faces. Note that the Wrap Plane icon is now highlighted, and you are prompted to select the tangent datum plane or planar face that will hold the unwrapped curves. Select the datum plane.

Use MB2 to specify that you are done selecting tangent planes.

478

Wrapping and Unwrapping Curves Selecting the Curves to Unwrap

Now the Curves icon is highlighted, and you are prompted to select the curves that you will unwrap. Select the end edges of the large cylinder and the entry and exit curves (yellow) of the intersecting cylinder.

Apply to unwrap the curves.

If you want to see the unwrapped curves without the other curves, make only the work layer visible. Undo the Unwrap. Choose Edit Undo List Use MB3 Undo -ORUse Ctrl-Z.

Wrap/Unwrap Curve-OR-

479

Wrapping and Unwrapping Curves Wrapping Curves Wrap works much like Unwrap, using cones, cylinders and datum planes.

Next you will go through the procedure to wrap a spline onto a large cylinder.

Wrapping and Unwrapping Curves Setting Up the Model

Change the Object Preferences color to red. Choose Preferences

Object.

Set the Color option to red.

Select the color red from one of the layers of the cube or from the Quick Access colors section, or Choose More to expand the Color dialog, enter the color ID number in the Number text field and press Enter, or Type red in the Color Name text field and press Enter. OK both dialogs. Make layer 11 the Work Layerwork layer, layer 3 Selectable, and layer 10 Invisible.

480

Choose the Layer Settings icon or choose Format Key in 11 in the Work field and press Enter. Double-click on layer 3 to change its status to Selectable. Double-click on layer 10 to change its status to Invisible. OK the dialog.

Layer Settings.

A white rectangle is displayed, which lies on the datum plane. This represents a label that has to be applied to the large cylinder.

It will be easier to work in the front view. Use MB3

Replace View

Front.

Wrapping and Unwrapping Curves Wrapping the Rectangle Turn on the Wrap option.

First you must select the body you will wrap the curves onto.

481 Select the large cylinder's outer face, then MB2 to signal that you are done selecting wrap faces. Select the datum plane, then MB2 to signal that you are done selecting tangent planes. Select the 4 lines that make up the white rectangle. Apply to wrap the curves.

The rectangle is "wrapped" from the datum plane onto the large cylinder. Remember that wrapped/unwrapped geometry is associative. Any edits made to the white rectangle at this point would be reflected in the mapped spline on the cylinder. Rotate the part to check out the results from other angles. Close the part file. Effects of Cut Line Rotations on Unwrap

This illustration shows how different Cut Line Rotation values can affect the result of an Unwrap operation.

482

Creating Section Curves You can use the Section option to create geometry that defines the intersection between faces or curves and specified planes. The intersection of a curve and a plane creates a point; the intersection of a face and a plane creates a curve. The accuracy of the section cut is determined by the Distance Tolerance value on the Modeling Preferences dialog.

483 Open part file crv_section_1.prt from the crv subdirectory.

Start theModeling application. Choose the Modeling icon.

Choose the Section Curve icon

or Insert

Curve Operation

Section.

The Section Curve dialog is displayed.

Creating Section Curves Using the Section Dialog

At the top of the dialog are options that let you specify the planes to be used for sectioning.

Select Planes - Select individual planes or groups of planes. If Associative Output is off, the Plane Subfunction is available for specifying planes. Parallel Planes - Specify a base plane, then specify incremental distances from it. Radial Planes - Specify an axis, then specify planes at angles around the axis. Planes Perpendicular to Curve - You select a curve, then section curves are created perpendicular to it. You control the spacing of the planes along the curve. Also at the top of the dialog are Selection Steps which prompt you to select Objects, Planes and other entities depending on the selected Plane Method.

484

Choose the Filter option.

You can limit your selection with this menu. Note that not all filtering options are available with each Plane Method. If the Group Section Data option is on, the curves and/or points created for each plane are grouped. This means that, if you have multiple objects to be intersected, and/or multiple section planes, the resulting section curves will be put into a group.

The Join Options let you choose whether or not to join curves that are created across faces or planes.

No Join creates a separate section curve across each face or plane when multiple faces/planes are selected. Join-Polynomial Cubic creates a cubic spline (recommended for most applications). Join-General Spline can be used if the section curve must have a degree other than three. At the bottom of the dialog is the Tolerance option, which allows you to specify how closely the section curves should lie to the objects and planes.

Also at the bottom of the dialog is the Confirm Upon Apply option. If this is on, you can decide whether or not to accept the results of the sectioning operation when Apply is pressed.

485

Creating Section Curves Creating Individual Section Curves

You will intersect a plane with the face. Check that the Join option is set to No. Make sure the Section Method is set to Select Planes. You must specify the geometry that the section planes intersect. Select the sheet body and confirm if necessary, then OK the dialog.

The Section Plane step

becomes active. You need to select the plane for sectioning.

Select the first plane symbol.

Apply the dialog. The plane is intersected with the face and the section curve is created.

486 Notice that the section curve you created goes all the way from one edge of the face to the other.

Creating Section Curves Specifying a Plane

You will create a plane 25 millimeters from and parallel to an existing plane and intersect the plane with the face. Turn the Associative Output option off.

Check that the Join option is set to No. Make sure the Section Method is set to Select Planes. You need to specify the geometry to be sectioned. Select the sheet body and confirm if necessary, then OK the dialog.

Choose Plane Subfunction. The Plane dialog is displayed. You can define the section plane using any of these options. Choose Parallel at Distance. The Offset Plane dialog is displayed. You want this 25 millimeters from and parallel to an existing plane. Choose Existing Plane. Choose the last plane.

487

The Point Constructor dialog appears. You will need to pick which side of the base plane that you would like the new plane to appear. Choose a point on the right side of the plane you just selected. The Plane Par at Dist dialog appears. You need to specify a distance from the existing plane. Change the distance to 25 and OK the dialog. The plane appears 25 millimeters from the selected plane. Apply the Section Curve dialog. The section curve is created on the face.

Creating Section Curves Creating Section Curves with Planes Perpendicular to a Curve

You can intersect a face with planes spaced along a selected curve (or a specified portion of it) and perpendicular to the curve (or a projection of it). You will intersect this part with four planes evenly spaced along the entire length of a selected curve.

488 Make layer 20 the work layer and layer 10 Invisible. Choose the Layer Settings icon or Format Layer Settings. Key in 20 in the Work field and press Enter. Double-click on layer 10 in the list box to change its status to Invisible. OK the dialog.

A spline is now displayed, along with the surface. Choose the Planes Perpendicular to Curve icon. Select the sheet body again, then OK the dialog. The Section Curve dialog changes. You can use the Spacing menu to control the spacing of the section planes along the curve (this menu contains the same options as the ones that are used for spacing points along a curve with the Point Set icon).

You can use the default Equal Arc Length. Key in 4 in the Number field and press Enter. Select the green spline. Plane symbols are displayed on the spline and you are returned to the Section dialog. As you can see in the TOP view, the planes are spaced evenly along the spline and are perpendicular to it.

OK the dialog. The section curves are created.

489

Close the part file.

Associative Section Curves Section Curves can be made associative. Associativity ties together (links) objects. You can automatically update a cross section curve if the object(s) being sectioned change and/or the sectioning plane(s) change. Open part file crv_section_2.prt from the crv subdirectory. Start the Modeling application. Choose the Modeling icon.

.

You will create an associative section curve, and then change the shape of the bottle.

Choose the Section Curve icon The Section Curve dialog displays.

or Insert

Curve Operation

Section.

490

Make sure the Select Planes method is chosen.

Turn on the Associative Output option.

Select the bottle (solid body) as the Object to Section, and use MB2 to move to the next selection step. Select the datum plane as the Section Plane, and OK the dialog. The associative section curve is created.

To change the shape of the bottle, you will need to edit one of the expression values. Choose Tools

Expression.

The Expressions are listed.

491

The expression named "a" controls the height of the bottle, and indirectly controls the location of all the sketches that control the shape of the bottle at different heights. Change the expression named "a" to be equal to 65.0. Choose a=88.9 from the list and change the value to 65.0 and press Enter.

OK the Expressions dialog.

Notice that the section curve updated. Leave the part open for the next section.

Associative Section Curves Removing Parameters

You can remove parameters from curves that are associated with features, making them nonassociative.

Choose the Remove Parameters icon

or Edit

Feature

Remove Parameters.

492 The Remove Parameters dialog displays. Set the filter to Curve. You need to select the objects whose parameters you wish to remove. Select all the white section curves by dragging a rectangle around them and OK the dialog. OK the warning message, and Cancel the Remove Parameters dialog. Choose Tools

Expression.

Now edit the expression "a", to be equal to 88.0, and OK the Expressions dialog.

Notice that the section curves did not update only the bottle. Close the part file.

Extracting Curves You can use Extract to create curves from bodies in your model. This activity will show you how to create curves from the edges of a face and how to create a "shadow outline" of a part. Open part file crv_extract_1.prt from the crv subdirectory.

493 This part consists of a sheet body with a single face. You will create curves along each of the edges of the face. Start the Modeling application. Choose the Modeling icon.

Choose the Extract icon

or Insert

.

Curve Operation

Extract.

Extracting Curves Curve Extraction Methods

A dialog displays the methods you can use for extracting curves. Edge Curves - Creates curves along the edges of a body. Isoparametric Curves - Creates curves along given U/V parameters on a face. Silhouette Curves - Creates an outline (silhouette) of the body. Silhouette curves are created as view dependent curves in the work view. All in Work View - Creates all edge curves, including any silhouettes from the visible edges of the bodies in the work view. Isocline Curves - Creates curves along which the draft angle on a set of faces is constant. Shadow Outline - Creates curves that show the outline of the bodies in the work view. You can choose to make Isocline curves associative to the geometry they are created from. Other extracted curves are not associative.

Extracting Curves Extracting Edge Curves

First you will create curves along the edges of this face. Choose Edge Curves. You can create curves from individual edges of a face, or you can use the dialog options to create curves from all the edges on a face, all the edges on a solid, or all the edges with a particular name.

494 Choose All in Face. Select anywhere on the sheet body. OK the dialog. The edges of the face are highlighted. OK the dialog again. The curves are created.

Extracting Curves Creating Isocline Curves

Isocline curves are used to trace along selected faces where the draft angle is constant. They can be used to split a surface, to create a "draft angle map" of a face, or to help in the construction of parting surfaces on a mold or casting. Turn the grid display of the face off to help you see the isocline curves more clearly. Choose the Edit Object Display icon or choose Edit Select the sheet body, then OK the dialog. Set both of the Grid Count fields to 0, then OK the dialog.

Object Display.

Turn the display of the WCS on. Choose the Display WCS icon

or WCS

Display.

You can see that the YC axis is pointing up. You will use the +YC axis as the isocline direction vector.

495 Choose Isocline Curves. The Vector Constructor dialog is displayed.

The cue line prompts you to select the isocline direction. The angles will be measured off this vector. Choose YC Axis, and OK the dialog. The Isocline Angle(s) dialog is displayed. Notice that the Associate option is on by default. This means your isocline curves will be associated to the geometry they are created from. If you do not want the curves associated to the geometry, you can turn this option off.

Notice also that the Angle field lets you key in one angle if you want to create a single isocline curve. However, you will create a family of isocline curves over a range of angles.

Turn On the Family option. Now the Angle field is grayed out, and the text fields in the center of the dialog are available, so that you can specify a range of angles and a step size.

496

You will leave the start and end angles at their default values, but increase the step size. Enter 5 for the Step value, then OK the dialog. Select the face, then OK the dialog. The isocline curves are created. Each curve represents the trace along the sheet body at an angle from the +YC axis, starting at -90 degrees and ending at +90 degrees, at every 5 degrees.

Extracting Curves Editing Associative Isocline Curves

When you create associative isocline curves, a feature is created, which you can edit.

Choose the Edit Feature Parameters icon

or Edit

Feature

Parameters.

You can also edit the isocline feature using Edit Curve, selecting any of the isocline curves, and then choosing Feature Parameters. In the Edit Parameters dialog, you can see the ISOCLINE_CURVE feature.

497 Select the isocline curve feature, either in the dialog or in the graphics area, then OK the dialog. A dialog is displayed, showing you the things you can change about an isocline feature. You can change the direction vector, replace the selected faces, or change the parameters you used to create the feature. Choose Feature Parameters. Change the Step value to 8, then OK three times. The part is updated.

Creating a Shadow Outline

The Shadow Outline option lets you create view-dependent curves that outline the bodies displayed in the work view. These curves are not associated to the body they were created from. Open part file crv_shadow_1.prt from the crv subdirectory.

Notice that the hidden edges have been removed in this view. This option will only work when hidden edges have been set to Invisible.

498 Start the Modeling application. Choose the Modeling icon.

Choose the Extract icon

or Insert

.

Curve Operation

Extract.

Choose Shadow Outline. Cancel the dialog. Layer 10 contains the solid body - you will make that layer invisible so that you can see the shadow outline curves. Make layer 10 Invisible. Choose the Layer Settings icon click on layer 10, and OK the dialog.

or Format

Layer Settings and double-

You can see that the shadow outline curves have been created.

The curves are not associative to the body they were created from. However, if you create a shadow outline in the Drafting application, when the bodies are changed, the old shadow outline is deleted and a new shadow outline is created as part of the drawing view update process. The accuracy of the extracted curves is affected by the Distance Tolerance on the Modeling Preferences dialog. If the curves are not accurate, you can try making the distance tolerance smaller and repeating the procedure. Close the part file.

Creating Intersection Curves Sometimes you need to create intersection geometry between faces and/or planes.

499 Analytic curves (lines, arcs, and ellipses) are created when possible. Otherwise, a spline is created. The curves that are created are associative to the bodies from which they were derived. Open part file crv_intersect_1.prt from the crv subdirectory.

This part consists of two tubes that intersect each other. You need to create curves at the intersections of the two outer cylindrical faces. Start the Modeling application. Choose the Modeling icon.

Choose the Intersection Curve icon Intersect.

.

or choose Insert

Curve Operations

The Intersection Curve dialog appears.

The accuracy of the intersection curve is determined by the value in the Distance Tolerance field.

Display the Filter options.

500 As you can see from the option list, you can intersect the following: Faces Datum planes (if you intersect two datum planes, the result is a single non-associative line) Sheet bodies Solid bodies Make sure the First Set selection step of the tubes.

is highlighted, then select the outer face of one

All objects selected as part of the first set will be intersected with all objects in the second set. Use MB2 to signal that you are done specifying the first set. The Second Set selection step automatically becomes active. Select the outer face of the other tube. Turn the Confirm Upon Apply option On. The Confirm Upon Apply option lets you accept, reject or analyze the intersection curve without leaving the Intersection Curve dialog. Choose Apply. The intersection curves were created along the intersection of the two selected faces.

A list of options appear. Feel free to explore some of these options for the spline generated. OK the Confirm Upon Apply dialog to accept the results. Close the part file.

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Offsetting a Curve on a Face Sometimes you need a curve that is offset from another curve, where the offset distance is measured along a face. Open part file crv_offset_face_1.prt from the crv subdirectory.

The part consists of a sheet body and a curve, which is on the face of the sheet body. Start the Modeling application. Choose the Modeling icon.

Choose the Offset In Face icon Face.

.

or choose Insert

Curve Operation

Offset in

Select the face of the sheet body. Select the curve (called the base curve). A vector is displayed, showing the direction of the offset along the face. If you want the offset to go in the direction opposite to the arrow, you can key in a negative Distance value. Key in 40 in the Distance field, then OK the dialog. Offset points are created, using the specified Distance value and the Modeling distance tolerance, then the offset curve is created through the points. Cancel the dialog and refresh the screen.

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Creating Planes You can create planes in Unigraphics NX, which can be used to create section cuts, project other entities onto, and to define limits of surfaces. A plane is represented by a triangle symbol with the right angle vertex on the origin point of the plane. The short leg is oriented along the implied X axis and the long leg along the implied Y axis. The scale of the symbol is fixed and the display of the plane object is permanent. It can be deleted, blanked and unblanked, and transformed just like any other object. (You should still be in part file crv_offset_face_1.prt and in the Modeling application.)

In any part file, choose the Plane icon

or choose Insert

Curve

Plane.

The Plane dialog is displayed.

Quick Reference: Plane Creation Options

This chart summarizes the Unigraphics NX Plane creation methods. Method Three Points Two Lines Point, Perpendicular Curve Plane of Curve Plane of WCS

Description Through 3 points specified using the Point Constructor Through the first line and parallel to the second (if they are coplanar, the plane contains both lines) Through a point and perpendicular to a curve The plane of an existing planar curve The XC-YC plane

503 Plane of CSYS Principal Plane Existing Plane Two Tangent Faces Point, Tangent Face Coefficients Parallel Thru Point Parallel at Distance Perpendicular, through Line

The X-Y plane of an existing coordinate system One of the planes of the WCS or parallel to one of the WCS planes Containing an existing plane Tangent to two solid faces (spheres or cylinders) Through a point and tangent to a face (sphere or cylinder) Specify A, B, C, and D in Ax+By+Cz+D=0 equation Through a point and parallel to a reference plane Parallel to a reference plane at a specified distance Through a line and perpendicular to a reference plane

Creating Planes Creating Planes Choose Principal Plane. Choose YC Constant. Key in 2 and OK the dialog. The Plane symbol (a triangle) is displayed. The Plane dialog is also displayed, and you could continue to create planes. Close all part files.

Editing Curves In this lesson, you will learn about some basic curve editing operations. You will learn how to: Edit lines, arcs, ellipses, fillets, and splines Trim objects and corners Divide and stretch curves These functions are found on the Edit Curve toolbar.

504

They are also found using Edit

Curve on the main menu bar.

Editing Curve Parameters Open part file crv_edit_1.prt from the crv subdirectory.

Start the Modeling application and bring up the Edit Curve Parameters dialog. Choose the Modeling icon

or choose Application

Choose Edit Curve Parameters icon

or Edit

Curve

Modeling. Parameters.

The Edit Curve Parameters dialog is displayed.

You use the Edit Curve Parameters icon to edit most types of curves, including:

505 Lines Circles and arcs Splines Ellipses and other conics Parametric curves such as helixes, offset curves, projected curves, etc. Notice that the dialog bar is displayed when you are in Edit Curve Parameters mode, just as it is when you are in the Basic Curves dialog. Move the cursor around in the graphics area. If the cursor position is being tracked in the dialog bar, turn the Tracking option off. Choose Preferences User Interface. Turn the Tracking option off, then OK the dialog.

Editing Curve Parameters Updating the Model

If you use curves to create a solid body or sheet body, and then you perform certain kinds of editing actions on the curves, you can use Update to force the body to be updated.

It is not necessary to use this option. When you leave the Edit Curve dialog, the body is updated automatically.

Editing Curve Parameters Editing Lines

The Status area will give you feedback about what is inside the selection ball as you move the cursor over the geometry. Move your cursor over the yellow line. Move the cursor up and down the line, and watch the Status area. Notice that, even though the entire line and all three control points are highlighted when any part of the line is in the selection ball, the status area tells you whether the system has detected a line, line midpoint, or line endpoint.

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The editing options you will have are directly dependent on what you select. In other words, if you select a line, you will have different editing options than if you select a line endpoint. This is true for all curve types when using Edit Curve Parameters. There are two ways you can edit a line: Select an endpoint and move it, or Select the line and change its parameters.

Editing Curve Parameters Moving the Endpoint of a Line Select the endpoint on the right end of the yellow line. (Make sure the endpoint dot is inside the selection ball. Otherwise, the line itself is selected.)

Rubber-banding is in effect. Key in XC=0, YC=50 in the dialog bar, then press Enter. The line adjusts immediately. The selected end of the line moves to the position you specified, while the other end remains stationary. Cancel the Edit Curve Parameters dialog. If you want to reverse the change, you can use MB3 Ctrl-Z, or you can use Edit Undo List.

Editing Curve Parameters Editing Line Parameters

You can also edit the length and/or angle of a line.

Undo in the graphics area or press

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Choose Edit Curve Parameters icon

or Edit

Curve

Parameters.

Select the line again, but this time avoid its endpoints.

Notice the dialog bar. It now contains the Length and Angle fields. Key in 50 in the Length field

and press Enter.

The length of the line is adjusted. The end nearest where you selected moves; the other end remains stationary. You can adjust the angle of a line in the same way.

Editing Curve Parameters Editing Arcs and Circles

There are several ways you can edit an arc or circle. You can: Use the Parameters option to enter a specific radius or diameter, or a new start and/or end angle. Use the Dragging option to change the radius, start angle, and/or end angle, or the location of the arc or circle. Create the complement of an arc.

Editing Curve Parameters Changing the Parameters of a Circle or Arc

One way to change a circle or arc is to just select it and input new parameter values in the dialog bar. Make sure the Parameters option is on.

508 Select the circle (be careful not to select one of its control points).

In the dialog bar, key in 20 in the Radius needed, to get to the radius field.)

field, then press Enter. (Move the toolbar if

The size of the circle is immediately changed.

Editing Curve Parameters Changing a Circle to an Arc

You can change a circle into an arc, by editing the start and end angles of the circle. Select the circle again. Press Tab until the Start Angle field

is highlighted, then key in 30.

Press Tab to move to the End Angle field

, then key in 180 and press Enter.

The circle changes to an arc that starts at 30 degrees and ends at 180 degrees.

Editing Curve Parameters Changing an Arc to Its Complement

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You can also change any arc to its complement. Select the arc, making sure not to select one of the control points. Choose Complement Arc. The arc is changed to its complement.

Editing Curve Parameters Changing an Arc by Dragging

You can use the Dragging option to change an arc by: dragging its endpoints to establish new start and/or end angles dragging its circumference to establish a new radius dragging its center to a new location

Choose the Edit Curve Parameters icon

to initialize the dialog.

Choose Dragging.

You can drag an arc or circle to a new location by selecting its center. Select the center of the arc and release.

510 Move the cursor around. Notice that the arc moves along with you. Click anywhere in the graphics area to establish a new location for the arc. (You could also establish an exact location for the arc by keying in values in the dialog bar or selecting geometry.)

Editing Curve Parameters Dragging the Size and End Points

You can also drag the arc itself, changing its radius. Select the arc, making sure not to select one of the control points.

Move the cursor around. Notice how the radius of the arc changes, while the two endpoints remain stationary. Just as when you are creating arcs, you can select other geometry and the arc will be tangent to it, or select a point and the arc will pass through it. When the arc looks approximately the same as when you started, click MB1. You can also drag the endpoints of an arc, effectively changing its start or end angle. Select the arc again, this time selecting its left endpoint.

Move the cursor around. Notice how the angle of the arc changes. Click MB1 when the arc looks approximately the same as when you started.

Editing Curve Parameters Editing Ellipses

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You can edit any of the values that were used when the ellipse was created. Select the ellipse. The Edit Ellipse dialog is displayed, with the ellipse's parameters in the text fields.

This is a general pattern with many parametric curves - you select the curve and a dialog is displayed that is the same, or nearly the same, as the dialog that was used to create the curve. Key in 30 in the Rotation Angle field, then Apply. The ellipse is turned and deselected. You could now select the same ellipse again, to edit it further, or select a different ellipse. Cancel the Edit Ellipse dialog.

Editing Curve Parameters Editing Fillets The interaction for editing a fillet is similar to the one for creating a fillet. NOTE: You cannot edit a fillet created in a sketch. If you need to edit the radius, you can edit

the associated dimensional constraint. Choose the Edit Fillet icon

or Edit

Curve

Fillet.

Choose Automatic Trim. Select the first line (object 1 as shown below), then the fillet (object 2), then the second line (object 3).

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You must select the lines in a counterclockwise direction, just as you did when the fillet was first created. The Edit Fillet dialog appears. It contains a text field for supplying a new fillet radius, and two other options: Radius Default - This option has two settings: Fillet (the default) - Each time you select a fillet, the value in the Radius field changes to the radius of the selected fillet. Modal - The value in the Radius field does not change when you select a fillet. If you want a new value, you must key it in. New Center - When this is turned on, you must specify a new general quadrant for the center of the fillet. Key in 20 in the Radius field, then OK the dialog. The size of the fillet changes. If you want to reverse the change, you can choose Undo on the dialog. Close the part file.

Editing Splines There are many ways you can edit an existing spline. You can: Move, add, or remove defining points. Change the slope, degree, curvature or stiffness. Move or add poles. Change the fit parameters. Smooth spline segments or whole spline. Change the spline display characteristics Open part file crv_edit_spline_1.prt from the crv subdirectory.

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The upper spline was created through points; the lower one was created through poles (vertices). The lower spline also has its control polygon displayed. The part is in inches. Start the Modeling application. Choose Modeling icon.

Editing Splines Adding a Defining Point to a Spline

Choose the Edit Curve Parameters icon

or Edit

Curve

Parameters.

Turn off the Display Original Spline option.

If you leave this option on, the original spline will continue to be displayed during the edit. Select the upper spline.

The Edit Spline dialog is displayed, showing all the ways you can edit a spline. You will add a point to this spline. Choose Edit Point.

514 The Edit Point dialog is displayed, and the defining points are displayed on the spline.

Editing Splines Adding a Point Turn the Add Point option on.

The cue tells you that you can specify a new point (using cursor location), or you can use the Point Constructor. OK to bring up the Point Constructor dialog. The Point Constructor dialog is displayed. You must specify the point to be added. Choose the Existing Point icon. Select the green point.

The spline immediately changes shape to pass through the new point.

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Choose Back to return to the Edit Point dialog. You could choose Undo from the dialog to reverse the change. Choose Back again to return to the Edit Spline dialog.

Editing Splines Editing the Slope Angle at a Point

Because this is a general spline, you can specify the slope at any defining point. (If this were a "fit" spline, only the end slopes could be specified.) Choose Change Slope. The Change Slopes dialog is displayed, along with the vectors representing the slopes at the two endpoints. (If any interior points have had their slopes defined, arrows will be shown there also.)

The cue prompts you to select the point that will have a changed slope. Indicate near the point on the right end to select it (the spline defining point that is nearest where you indicate is selected).

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The dialog shows different ways you can specify the slope at the selected point. For a brief summary of these options, select the link below.

More About: Slope Definition Options

Here is a brief description of the different ways you can define the slope at a point on a spline. Automatic Slope computes the slope automatically based on the position of nearby points. Vector Component defines the slope by entering WCS values. Direction to Point defines the slope based on a line between the spline definition point and

another point that you specify. Vector to Point - defines the slope at a point by your specifying of another point, using the

Point Constructor. The vector between the two points defines the slope of the curve at that defining point. Also, the distance between the two points (i.e., the magnitude of the vector) determines how strongly the slope affects the shape of the curve. Slope of Curve calculates the slope of the spline using an existing curve. Angle defines the slope using an angle, entered by the user. The angle is measured from the

XC axis in the XC-YC plane; counterclockwise about the ZC axis.

Editing Splines Changing the Slope Angle You will change the angle of the slope at this point. Choose Angle. Key in 45 in the Angle field, then OK the dialog. The shape of the spline changes to match the new slope.

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Cancel the dialog. Refresh the graphics area. Use MB3

Refresh, or press F5.

Unlike most operations, if you want to undo a spline edit, you must use the Undo button on the Change Slopes dialog.

Editing Splines Using Curve Analysis with Spline Editing

You can edit a spline and simultaneously see a graph of the changes you are making to it. The graph is generated from the spreadsheet application. Select the lower (green) spline. (You can select the spline itself or its control polygon.)

Choose the Curve Analysis - Graph Options icon.

(You can also choose Analysis

Curve

Graph Options.)

518 The Curve Analysis-Graph dialog appears. You will make a few changes in this dialog.

Editing Splines Graph Options

The Height and Width slider bars allow you to change the size of the graph window that will be displayed. Move the Height slider bar down to 200.

Move the Width slider bar to approximately 400. and OK the dialog.

This will produce a smaller output window which is more manageable. OK the dialog. (When you choose OK, the curve graph window will fill most of the screen. So, you will want to resize it and move it so you can see all of what you need.) As well as changing the window size and location, you may also want to change the size of the text to approximately 9.

Editing Splines Displaying the Curvature Comb

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The curvature comb provides another graphic display depicting the curvature of the spline.

Choose the Curve Analysis - Combs icon

or choose Analysis

Curve

Combs.

The curvature comb is displayed in the graphics window, and the Curvature Graph pop-up window is also displayed.

Choose Curve Analysis-Combs to turn off the comb display. The comb is persistent and always available. The display of it is turned off or on with the Curve Analysis-Combs icon. It is also associated with the spline - as the spline changes, so will the comb. You will leave the graph up during the next few editing procedures to see how it works.

Editing Splines Moving a Pole

A pole is a vertex of a spline's control polygon. You can change the shape of a spline by moving its poles or adding poles. (All splines have poles, regardless of how they were created.) Choose the Edit Curve Parameters icon

or Edit

Curve

Parameters.

Select the lower spline, by selecting the spline itself or its control polygon.

520

Choose Edit Pole from the Edit Spline dialog. The Edit Pole dialog is displayed. Make sure the Edit Method is set to Move Pole. You can move a pole in three different ways (using the Move Pole By options): To a specified destination point, using the Point Constructor. By dragging. By delta values.

Editing Splines Setting the Options Set the Move Pole By option to Delta Offset. Select the pole you want to move by indicating near it.

You will offset this pole by 1 inch in the +YC direction. Key in 1.0 in the DYC field (leave DXC and DZC at their default values of 0), then OK. The pole moves and the shape of the spline changes.

Editing Splines

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The Curvature Graph

The Curvature Graph also updates.

You could choose the Undo button to return the spline to its previous shape if necessary. If you edit the poles on a spline that was created through points, you can use the Restore Defining Data option (on the Edit Spline dialog) to return the spline to its original shape.

Editing Splines Dragging a Pole Without Changing the Slope at the Endpoint

You can also drag the poles of a spline. In addition, you can use the Constrain End Slopes option to move a pole without changing the slope at the endpoint. You will continue to work with the same spline. The Edit Pole dialog should still be displayed. Choose Back to return to the Edit Pole dialog. Set the Constrain option toEnd Slopes.

Put the cursor on the second pole in the control polygon, then press and hold down MB1.

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Move the cursor around. As you can see, the shape of the control polygon and the spline is changed. However, the slope at the endpoint does not change. Notice that the graph is continually updated as you drag the pole. Release MB1 when the desired shape is displayed. Drag other poles in the same way.

Editing Splines Micro-Positioning

For "fine tuning" a spline, you can use Micro Positioning. This is accessed by holding down the control key while dragging the pole. You can also lock Micro-Positioning on by choosing the Lock icon.

The micro positioning value is a scale. With it set to the default of 0.1, the pole being dragged will move only 1/10 the distance it is dragged. Hold down the Control key and slightly drag any pole. You can see that the amount of movement of the pole is much smaller than before. This lets you do fine adjustments on the shape of the spline. Cancel the Edit Pole dialog. Close the Curvature Graph window.

Editing Splines

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Changing Stiffness

You can use the Change Stiffness option to make a spline more or less sensitive to undulations (reversals of curvature) in its control polygon. The control polygon remains the same - the segmentation changes. Choose the Edit Curve Parameters icon

or Edit

Curve

Parameters.

Select the upper spline.

The Edit Spline dialog is displayed. Choose Change Stiffness. A warning message is displayed that says this operation will remove defining data and associated dimension from the spline. If this is OK with you, continue with the procedure! OK the warning dialog.

Editing Splines Making the Changes

A dialog is displayed, showing you that the current degree of this spline is 3 (the default). You will "stiffen" the spline by increasing its degree. Key in 7 and then OK the dialog. Increasing the degree makes the curve "stiffer" - it follows the control polygon less closely. You can see that it now appears much "flatter".

524 Choose Undo from the dialog. The curve returns to its former shape. This time you will decrease the stiffness of the spline. Choose Change Stiffness again. OK the warning dialog. Key in 2, then OK the dialog. Decreasing the degree reduces the stiffness of the curve, allowing it to follow the control polygon more closely.

Cancel the Edit Spline dialog.

Editing Splines Smoothing Curves

You can smooth out open splines, either the whole spline or a segments of a spline based on defining points. Choose the Edit Curve Parameters icon

or Edit

Curve

Parameters.

Select the upper spline.

Choose Smooth. The Smooth Spline dialog appears. Notice that the Smooth option is grayed out. As the spline is being smoothed, certain points will be held within a tolerance. To determine these points, the spline is divided into segments. The points are at the ends of these segments. The initial "division" is determined by the number of segments in the spline. These segments are determined by equal arclength, not the actual segments of the spline. The segmentation can later be changed, if you wish.

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Editing Splines Some Options

The Source Curve option lets you choose whether you wish to smooth the original spline or a spline that is currently being edited. Change Source Curve to Current.

Choose Approximate to accept the 7 Segments number.

Editing Splines Smoothing Again

The Smooth option becomes available. At this point, you can either smooth the entire spline or the spline at individual points. The spline is partitioned into 7 segments.

The Smooth option is generally most useful at the beginning of the smoothing process; you can further refine the smoothing by smoothing individual points. Choose the Smooth option. The spline is smoothed based on the Threshold factor. The points at the ends of the segments will be moved no more than the Threshold value. Smoothed splines have a degree of 5 after smoothing. The Undo option becomes available after you have modified the spline. If you have made several modifications, Undo will step back through the modifications.

526 Cancel the dialog. More About: The Smoothing Threshold

The Threshold is the maximum distance points can move from the original spline. The smaller the threshold, the closer the new spline will match the original spline.

Change Shape by Template You can transform a spline (or a set of splines) from its current shape to match the shape of another spline while maintaining its original start and end positions of the edited curve. This function is included in the Shape Studio license. Open part file crv_shape_1.prt from the crv subdirectory, then start the Modeling application.

Display the Free Form Shape toolbar. Choose View Toolbars Free Form Shape - OR

Customize. Then from the Toolbars tab, choose

527 Use MB3 in the toolbar area and choose Free Form Shape.

Choose the Shape by Template icon Shape by Template.

or Edit

Free Form Feature

Change Shape by Template Selecting the Spline

The Shape by Template dialog appears.

Visually compare the poles, curvature and general shape of the two splines. You will transform the top curve to have the same segmentation, degree, and shape as the bottom spline. To do this, the Refit Curve option must be on. If you do not wish to directly change the Spline to Shape, you can make a copy of it by turning on the Edit a Copy option. Make sure Refit Curve is on, and the first selection step, Spline to shape, is active. Select to the left of the top spline for the Spline to Shape.

Press MB2 to move to the next selection step, Template Spline. A temporary arrow is placed at the start of the spline to shape. The start is determined by which end you select.

528

You can change the start of a spline by deselecting the curve (Shift + select) and reselecting the spline at the opposite end.

Change Shape by Template Selecting the Template Select to the left of the bottom spline for the Template Spline.

Again a temporary arrow is placed at the start of the spline, the spline to shape is fit to match the template curve's degree and segmentation, and the slider bar on the dialog is set to the far left.

Change Shape by Template Using the Slider

As the slider is moved to the right, the spline comes closer to matching the shape of the template as well. Slowly move the slider all the way to the right, and watch the effect.

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The right-most position of the slider maintained the original start and end positions of the spline to shape, but the rest of the spline was properly adjusted to match the template splines character. Note that the Deviation Analysis option becomes available.

Change Shape by Template Deviation Analysis

You can use the Deviation Analysis option to view the deviation between the original curve and the change curve.

Once selected, the Deviation Check dialog displays for you to make changes to the given options, but selection is disabled. If you were editing multiple curves simultaneously, when the Deviation Check dialog is displayed, the input settings are made to all selected curves to shape.

530 Cancel the dialog. OK the Shape by Template dialog. Close the part file.

Trimming Curves You can trim a curve (line, arc, conic, spline, or string of curves) to its intersection with one or two bounding objects. Bounding objects can be single (or strings of) curves, edges, faces, planes, points, or screen positions (view points). You can also choose to make the trim associative. That means that if the boundaries or curves that were trimmed are changed, the trim will update. Open part file crv_trimcrvs_1.prt from the crv subdirectory.

Start the Modeling application and bring up the Trim Curve dialog. Choose the Modeling icon Choose the Trim Curve icon

or Application or Edit

Curve

(This function is also available on the Basic Curves dialog.)

Trimming Curves Options You are presented with the Trim Curve dialog.

Modeling. Trim.

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There are four methods for finding intersections to trim to. All four options allow you to trim curves or strings to other curves, strings or other objects.

Shortest 3D Distance If the objects are not coplanar, the point that will be trimmed to will be the closest location in 3D space. Relative to WCS It projects the boundaries to the curves being trimmed along the ZC axis. Along a Vector With this, you have the ability to choose how the boundary curves or strings are projected onto the string being trimmed. Along Screen Normal With this, the boundary curves or strings are projected onto the string being trimmed along view normals. Since all the geometry in this file is coplanar, you will use Shortest 3D Distance. Change the Method to Find Intersections to Shortest 3D Distance.

Trimming Curves Trimming Curves to One Bounding Object Make sure Single Selection is on.

This makes simple trims easier by automatically progressing to the next selection step after you have made a selection.

If you want to select strings of curves, this switch should be off.

532 The cue asks you to select the objects that define the first trim boundary. Select the arc for the first trim boundary.

The cue now asks you to select the objects that define the second trim boundary. If you do not have a second bounding object, you can choose MB2 to bypass this step. Use MB2 to specify that you do not have a second bounding string.

Trimming Curves Curve Trim Options

You can choose Associative Output. This switch is found near the bottom of the dialog.

If this is on, when the trim is done the trimmed curve or string will be associated with the original curve and the boundary objects. If any of them change, the trimmed curve will update. The system will also create a TRIM_CURVE feature, which can be edited using Edit Parameters. Make sure Associative Output is off.

You can also specify what will be done with the selected Input Curves. If Associative Output is on, you will get the following options: (Note that Delete and Replace are greyed out.)

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Retain will keep the original curve's blank status. Blank will blank the original (trimmed) curve. If Associative Output is off, you will get the following options:

Retain will keep the original string's blank status. Blank will blank the original (trimmed) string. Delete will delete the original input (trimmed) string, unless the input string was used to generate a feature (such as an extrusion). Replace will replace the input curves with the trimmed curve. Anything associated with the original (input) string will be associated with the output string. Set Input Curves to Replace.

Trimming Curves More Curve Trim Options At the middle of the dialog, there are some more options:

Trim Bounding Objects - When this option is off (which is the default), only the selected string is trimmed. If you turn this option on, both the selected string and the bounding string(s) are trimmed. The bounding strings are also marked with the small circle to tell you which end will be adjusted. Reuse Bounding Objects - If this is turned on, the selected bounding objects will remain selected after the trim, so additional curves can also be trimmed to them. Spline Extension - When you select an object to be trimmed and it does not extend to an intersection with a bounding object, the selected object is extended where possible.

534 For lines, arcs, and conics, this is a simple mathematical extension of the curve. However, for splines, you must specify the correct spline extension shape: Natural - This extends the spline from its end point along the "natural path of the spline." Linear - This extends the spline using a line whose slope is equal to the slope of the curve at the endpoint. Circular - This extends the spline using an arc whose radius matches the radius of curvature at the end of the spline. None - The spline is not extended. Make sure Reuse Bounding Objects is turned on.

Trimming Curves Selecting the Objects to be Trimmed Select LINE1 as the string to trim.

The line is extended and trimmed to the bounding object you defined.

Since you turned on Retain Bounding Objects, you can continue to select more curves and they will all be trimmed to the same bounding object. Select LINE2 as the string to trim.

535 The line is trimmed. Select LINE 3 to be trimmed.

Trimming Curves Specifying the Intersection Point

When there is more than one intersection between the curve and the bounding object (as there is with LINE3), the curve is trimmed to its nearest intersection with the bounding object. However, you can indicate exactly which intersection point you want to trim to. To trim to a specific intersection, turn Use Inferred Intersection off. When you select the curve to be trimmed, you will be prompted to select which point you wish to trim to. This time you will trim LINE3 to its other intersection with the arc. Specify the string to be trimmed. You will trim the lower end of LINE3 to the further intersection point. Select LINE3 near its right end.

The line is trimmed.

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If the trim does not come out the way you want, just choose MB3 -> Undo and try again. Cancel the Trim Curve dialog. Use MB3

Undo (or Ctrl-Z) 2 times, until the part is returned to its original state.

Trimming Curves Trimming a Curve and Bounding Object

This time, you will trim the curve and the bounding object at the same time.

Choose the Trim Curve icon

or Edit

Curve

Trim.

When you are also trimming the bounding objects, it does matter where you select them. The portion that you select is the portion that is trimmed away or lengthened. The end on which you select it will be marked with a small circle. You can change this using the Trim/Extend switch on the dialog. Turn the Trim Bounding Objects option on.

Leave the Associative Output option off, and make sure Input Curves is set to Replace. Select the arc toward the left end.

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Notice the circle on the left end of the arc. That is the end that will be adjusted, in this case. Use MB2 to specify that you do not have a second bounding object.

Trimming Curves Finishing the Trim Select LINE2 near the lower end.

This time, the selected part of the line and bounding curve are both trimmed to the intersection point.

Cancel the Trim Curve dialog.

Trimming Curves Trimming a Curve to Two Bounding Objects

538 You can trim a curve to two bounding objects at the same time. You can trim away the outer portions of the trim curve or the middle of the trim curve. Make layer 2 the Work Layer and layer 1 Invisible. Choose the Layer Settings icon. Key in 2 in the Work field, then press Enter. Double-click on layer 1 to change its status to Invisible. OK the dialog.

The part should now look like this:

Choose the Trim Curve icon Say you need to trim both ends of the arc to the lines. First you need to define both lines as bounding objects. Make sure Reuse Bounding Objects is on, Associative Output is off, and Input Curves is set to Replace. Make sure Trim Bounding Objects is off.

Trimming Curves Selecting the Boundaries Select one of the two lines as first trim boundary. The order of selection is not important. Then select the other line as the second bounding object.

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Trimming Curves Selecting the Curve to Trim Now you need to select the trim curve and specify how you want it trimmed. You do so by where you select it. Select the arc near one end.

Both of the outer segments of the arc are trimmed to the bounding curves.

Trimming Curves Trimming the Inner Portion of the Curve How would you use this same procedure to trim the inner segment of the spline? Remember that the two lines are still defined as the bounding curves and the cue says "Select string to trim."

540 Select the spline between the bounding objects.

The middle segment is removed leaving only the outer segments.

Cancel the dialog.

Trimming Corners You can trim a corner where any two curves intersect. Open part file crv_trimcrnr_1.prt from the crv subdirectory.

Start the Modeling application. Choose the Modeling icon.

Choose the Trim Corner icon

or Edit

Curve

Trim Corner.

541 The Trim Corner dialog is displayed. You need to have both objects inside the selection ball when you select in order for them to trim.

Trimming Corners Trimming Two Lines to a Corner Select the corner intersection of the two green lines as shown below.

If you receive the QuickPick confirmation toolbar, choose either of the two lines. The segment of each object that is closest to the center of the selection ball is trimmed away.

Trimming Corners Trimming a Line and an Arc to a Corner Now you will trim the corner where the line and arc intersect. Select the corner you want to trim.

Again, if you receive the Quick Pick confirmation dialog, choose either 1 or 2. The corner is trimmed.

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Trimming Corners Trimming the Intersection of an Arc and a Spline Next, you will trim the corner where the arc and spline intersect. The zero degree position of a circle is determined when it is created. It is the point where a line through the center of the circle and parallel to the current XC axis would intersect the circumference of the circle.

When you trim circles, the selected portion of the circle trims back from this zero-degree position, as in these examples:

Trimming Corners Trim the Curves Select the corner to be trimmed.

543 Because a spline is involved, a message appears warning you that the spline's defining data will be removed if you continue.

OK the message dialog. The corner is trimmed.

Note that the lower part of the circle was trimmed back from its zero degree position, because that was the portion you selected.

Dividing Curves You can divide a curve into a series of like segments (i.e., line-to-line, arc-to-arc, etc.). The following characteristics apply to this operation: Each segment created is a separate object and is assigned the same font as the original curve. The new objects are placed on the same layer as the original curve. The defining points for splines are deleted. You will use the same part file that you used for the Editing Splines section. Open part file crv_edit_spline_1.prt from the crv subdirectory.

544 If necessary, start the Modeling application. Choose the Modeling icon.

Choose the Divide Curve icon

.

or Edit

Curve

Divide.

The Divide Curve dialog is displayed showing the different methods for dividing a curve. For more information about these methods, select the link below.

More About: Methods of Dividing a Curve

Here is a brief description of the different methods for dividing a curve. Equal Segments - Divides the curve into segments of equal length or into segments determined by the parameters of the curve. Segments by Bounding Entities - The curve is divided at its intersection with bounding entities. These can be points, curves, planes, and/or faces. Input Arclength Segments - Divides a curve based on the arc length defined for each segment. (Arc Length is a mathematical term and should not be confused with arc. Arc length is not only for arcs.) At Knotpoints - Divides a spline at selected knotpoints. At Corners - Divides a spline at corners. A corner is a knotpoint where there is bend in the spline, i.e. when one spline segment end direction is not the same as the start direction of the next segment. Remember, "defining points" and "knotpoints" are not the same thing (although, for a cubic spline with a degree of 3, the defining points and knotpoints are in the same locations). Defining Points are the points used to define the spline. If a spline is created through poles, it does not have any defining points, and you will not get the warning message.

545 Knotpoints are the endpoints of the spline segments. Bezier splines, because they only have one segment, only have two knotpoints (one at each end of the spline).

Dividing Curves Dividing a Spline Choose At Knotpoints.

The Divide at Knotpoints dialog is displayed. Select the upper spline.

Because this procedure will delete the defining points of the spline, you get a warning message.

OK the warning dialog. The spline is highlighted and its knotpoints are displayed.

The dialog gives you three options for selecting the knotpoints where you want to divide the spline. Choose By Screen Position.

546 The cue prompts you to indicate near the desired knotpoint. Indicate near the two knotpoints shown below.

OK the dialog.

Dividing Curves Dividing the Spline There are two options on the Divide Curve dialog at this point. You can choose to either segment the curve or select more points. Segment Curve - allows you to define more division points. Divide Curve - divides the curve. Choose Divide Curve. The spline is divided. Even though the spline looks the same, there are now actually three separate splines. Choose Information

Object.

Place your cursor over each of the three curves.

Each of the 3 curves highlights separately. Cancel the dialogs.

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Stretching Geometry You can use the Stretch option to move objects while simultaneously stretching or shrinking selected lines. You can move most object types, but you can only stretch and shrink lines. Stretch works for all object types except sketch, group, components, solids, faces, and edges. Open part file crv_stretch_1.prt from the crv subdirectory.

If necessary, start the Modeling application. Choose the Modeling icon.

Choose the Stretch icon

or Edit

.

Curve

Stretch.

The Stretch Curve dialog is displayed. You can use the Point to Point option to stretch objects by specifying a reference point and destination point, or you can use the text fields to stretch objects by delta values.

Stretching Geometry Selecting Geometry Individually You first need to specify the geometry to be stretched. You can select objects individually or by using a rectangle. You will select the lines individually this time.

548 Select the two lines towards their upper endpoints.

When you select lines individually, the line endpoint nearest the selection point will be stretched. If the selection point is near the midpoint of the line, the entire line will be moved (and not stretched). There are some other things to be aware of when you stretch a line endpoint: Lines selected with the rectangle method are extended if the rectangle contains one of the line's endpoints. Otherwise, the entire line is moved. If a line to be stretched is contiguous to a fillet, the tangency of the fillet to the line may be lost. Lines stretched to a zero length are deleted. Associated objects are adjusted when the display is updated.

Stretching Geometry Stretching the Selected Geometry

Because you did not choose the Point to Point button, you need to key in delta values. You will stretch the lines upward. Key in 2.5 in the Delta YC field, then Apply the dialog. The selected lines are stretched by 2.5 in the YC direction. The "asterisk" marks the original endpoints of the lines.

549 Apply again. The lines are stretched 2.5 mm farther.

Choose Undo from the dialog.

The most recent stretch is reversed. Choose Undo again. The first stretch is reversed and the option is now grayed out, since you cannot back up any farther.

Stretching Geometry Selecting Geometry Using a Rectangle You can also select objects to stretch using a rectangle. Here is how rectangle selection works: Any line endpoints that are enclosed in the rectangle will be stretched. Any complete objects that are enclosed in the rectangle (including lines) will be moved. If only part of an object (other than a line) is within the rectangle, the object will not be selected. Click and drag a rectangle as shown.

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The graphics area should now look like this:

Notice that the upper endpoints of the lines were selected (because the lines were partially in the selection rectangle) and the entire circle was selected (because it was completely inside the rectangle). Again, you will stretch these curves upward. Key in 7.5 in the Delta YC field, then Apply. This time, the selected lines are stretched by 7.5 in the YC direction and the circle is moved by the same amount. (Remember, only lines can stretch - all other curves are moved.)

Cancel the dialog.

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Surface Update while Editing Curves Surfaces will update as you edit the parent curves. When you edit the points or poles of a spline or edit the endpoints of a line or the end points, radius, or center of an arc, Unigraphics NX performs a local update to the First Level Child features or all features each time the mouse moves or stops moving. Open part file crv_surf_update_1.prt from the crv subdirectory, then start the Modeling application.

Surface Update while Editing Curves Modeling Preference Settings

For this function to work, two settings must be made in Modeling Preferences. Choose Preferences

Modeling.

Set Dynamic Update to Incremental.

Continuous updates the surface as you edit the curve. Incremental updates the surface immediately after you make a specific edit to the curve. Set Immediate Children to First Level.

552 If this is set to All, all features that are driven by the curve (as well as the immediate children) will update as you edit the curve. OK the Modeling Preferences dialog.

Surface Update while Editing Curves Editing the Spline

Choose the Edit Curve Parameters icon Select the middle white spline.

The Edit Spline dialog displays. Choose Edit Pole.

Surface Update while Editing Curves Dragging a Pole

This displays the Edit Pole dialog.

You can leave all the default settings.

or Edit

Curve

Parameters.

553 Select one of the poles and drag it. When you release MB1, watch the surface update. If you had set Dynamic Update to Continuous, the surface would have changed as you dragged the pole. Depending upon which pole you chose, your display might look like this:

Close all part files.

-SketcherSketching in Unigraphics NX A Unigraphics NX sketch is a named set of curves and points located on a specified plane. It may or may not have constraints (rules) attached to it. Any features created from a sketch are associated with it - if the sketch changes, so do the features created from it. Sketches are useful when you want to be able to easily control an outline of a feature. Especially if it may need to be changed in the future. Sketches can be edited very quickly and easily.

554 This model has three sketches in it - each was extruded to create a different feature in the model. The sketch geometry is shown in cyan, and the model in green.

Ways to Use Sketches

There are many ways that you can use sketches. A sketch can be revolved to create a feature, as shown in this illustration.

A sketch can also be extruded (and, optionally, tapered).

555 A sketch can be swept along a guide (and that guide can also be a sketch, as shown below.)

Sketches can be used as generator profiles for free form bodies, as shown below)

A sketch can also be used as a law curve to govern the shape of a model or feature. Remember, when a feature is created from a sketch, the feature is "associated" with the sketch, and is parametrically controlled by the sketch. Therefore, if you edit a sketch, any associated features are updated. In this course, you will access the Sketcher in the Modeling application. However, many other applications also allow you to use the Sketcher.

General Procedure for Using Sketches When you want to use sketches in your model, you should follow this general procedure: Establish the design intent for the feature or part that you want to model. Use your company standards to set up the layers and/or categories for the sketches that you plan to create. (It is usually a good idea to place each sketch on its own layer.) Check and set the sketch preferences. Create the sketch and the sketch geometry.

556 Constrain the sketch according to your design intent. Use the sketch to develop a feature on your model.

Sketches - Pre/Post V13.0 The procedure for creating and editing sketches, as well as the sketch solver, changed in Unigraphics V13.0. If you have any sketches that were created in any version prior to Unigraphics V13.0, the PreV13.0 Sketches lesson explains some of the differences and shows you how to edit these sketches.

The Basics In this lesson, you will learn some of the basic principles of how to create a sketch, as well as how to create geometry in the sketch and create some constraints (rules) for the sketch. You will create a sketch and extrude the sketch into a solid. You will also edit the sketch in several ways, and watch the solid update.

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Creating a Sketch Open part file skt_create_1.prt from the skt subdirectory.

This part file appears to be empty, but it actually has some layer categories defined. You will use the Modeling application for sketch creation in this course. However, you can also create sketches in other applications, like Drafting or Manufacturing. Start the Modeling application. Choose the Modeling icon

or choose Application

Modeling.

Creating a Sketch Examining the Layer Categories Notice that layer 10 is the current work layer. This part file contains categories for layers, including layers for sketches. Before you start to create a sketch, you should check that you are creating it on a layer that is assigned to sketches. Check to see which layers are assigned to the SKETCHES category. Choose the Layer Settings icon or choose Format Layer Settings. In the upper list box, select the SKETCH_GEOMETRY category.

558 You can see that, when you select the category named "SKETCHES", layers 21 through 40 are highlighted in the Layer/Status box. This shows you that these layers are all assigned to that category.

You will create your sketch on layer 21. Make layer 21 the work layer. In the Layer Settings dialog, key in 21 in the Work field and press Enter and then OK the dialog.

The Sketcher Task Environment The Sketcher Task Environment lets you create and work with sketches.

Choose the Sketch icon

or choose Insert

Sketch from the menu bar.

You are now in the Sketcher Task Environment. This is like an application. Only the icons for usable functions are available. You are provided four toolbars for working with sketches.

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The Sketcher Task Environment The Sketcher Toolbar

Finish Sketch is for exiting the Sketcher Task Environment. Sketch Name is the name of the current active sketch. You can also use this to change the name of a sketch. Reattach is for attaching an existing sketch to a different face or plane. Orient View to Sketch is for orienting the view to be looking directly at the sketch plane. Orient View to Model is for returning the orientation of the view to the one displayed prior to entering the Sketcher Task Environment. Create Positioning Dimension is for creating, editing, or deleting positioning dimensions. Update Model will update the model, using the changes made to the sketch, without leaving the Sketcher Task Environment. Delay Evaluation is for delaying the evaluation of the active sketch. Normally a sketch is evaluated as you work on it. Evaluate Sketch is for asking the system to evaluate the sketch. This is only available when Delay Evaluation is on.

The Sketcher Task Environment The Sketch Operations Toolbar

Mirror is for creating a mirror image of selected sketch curves, about a line. Offset Extracted Curves is for creating a set of curves that are offset from curves extracted into the sketch. Edit Curve is for editing sketch curves. Edit Defining String is for changing which curves in a sketch are used to generate a specific feature.

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Add Objects to Sketch is for adding non-sketch curves to a sketch. Add Extracted Curves to Sketch is for creating an associative copy (within a sketch) of curves/edges that are outside the sketch.

The Sketcher Task Environment The Sketch Constraints Toolbar

Dimensions is for creating and editing dimensional constraints. Create Constraints is for creating geometric constraints. Automatic Constraint Creation is for creating many constraints at once. Show All Constraints will display all created geometric constraints on the graphics screen. Show No Constraints will remove the display of all created geometric constraints. Show/Remove Constraints is for listing and/or removing geometric constraints. Animate Dimensions will vary a selected dimension graphically. Convert To/From Reference is for changing geometry or dimensions to or from reference. Reference dimensions are not used to evaluate the sketch. Reference geometry is not used for creation of features. Alternate Solution will find the other solution of a dimension, or the other solution between an arc/circle and a line. Infer Constraint Settings is for controlling which constraints will be created while creating geometry.

The Sketcher Task Environment The Sketch Curve Toolbar

Profile is for creating a series of connected lines and/or arcs.

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Line is for creating lines. Arc is for creating arcs. Circle is for creating circles. Derived Curves is for creating lines parallel to other lines at a distance, or for creating a bisector line. Quick Trim will trim geometry to other geometry. Quick Extend will extend geometry to other geometry. Rectangle will create a rectangle (four lines - two horizontal and two vertical). Fillet is for creating arcs that are tangent to other geometry, with or without trimming the other geometry. Spline is for creating free form splines. This is much the same as creating splines outside the sketch. It is covered in the Curves course. Point is for creating Points, either associative or not. Ellipse is for creating ellipses, or general conics.

The Sketcher Task Environment The Selection Toolbar When in the Sketcher Task Environment, the Selection toolbar does not contain an icon for features, and has two new icons:

Select Sketch Objects is for selecting sketch geometry and sketch dimensions. Select Constraints is for selecting geometric constraints.

Naming the Sketch The Sketch Name field in the sketcher toolbar shows the default sketch name prefix (SKETCH_ ) followed by a three digit number. This is the default sketch name.

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A descriptive name will make it easier for you to remember what it contains. (Your company may have standards for sketch names.) You can enter a different sketch name before or after creating a sketch. However, for now, you will leave this name as it appears.

Choose the OK icon. The sketch is created. As was temporarily displayed earlier, the system now actually created a datum plane (represented by a square) on the XC-YC plane, and two datum axes (two arrows) on the XC and YC axes. The view is automatically oriented so you are looking directly at the sketch plane (down the sketch Z axis). Datum planes and datum axes are construction tools that are taught in the Feature Modeling CAST Online course.

Sketch Geometry You will use the Sketch Curve icons to create some geometry in the active sketch. As you create sketch curves, the system automatically applies some rules (constraints) to the created curves. This depends on how the curves are created, and some settings that are covered later.

563 Move your cursor over each icon in the Sketch Curve toolbar to read its name.

Sketch Geometry Creating Sketch Geometry You will now create the sketch curves shown below.

One of the beauties of working with a sketch is that you do NOT need to create the curves exactly - you can apply constraints (rules) to change them later. This is called "freehand sketching". HOWEVER, if the curves are to share end points (as in the outer curves in the sketch above), it is best to create them that way. When you do so, the shared end points will ALWAYS have the same location. Thus if one of the curves moves, so will the other. The above also works with arc centers. If you create an arc with its center at the end of a line, if the line moves, so will the arc.

Sketch Geometry Moving the Plane and Axes to Another Layer You do not need to have the datum plane and datum axes displayed. Exit the Sketcher.

Exit the sketcher by choosing the Finish Sketch icon. Move the datum plane and datum axes to Layer 61.

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Choose the Move to Layer icon or choose Format Move to Layer. Select the datum plane and datum axes, and then OK. Type in 61 in the Destination or Category field and press Enter.

Now you are ready to create the curves in the sketch.

Sketch Geometry Creating Sketch Curves Choose the Sketch icon. The system assumes you want to create a new sketch. You do not want that, you want to work on the sketch you already created. Choose SKETCH_000 in the Sketch Name options box. Use Shift-MB2 to Pan the center of the screen near the lower left corner. Choose the Profile icon. Profile allows you to create a series of lines and arcs, connected end-to-end. A series of four icons appears at the upper left corner of the graphics screen. These are for controlling what you create, and how you create it.

Sketch Geometry Creating the First Line

In the toolbar at the upper left corner of the screen, make sure the Line icon is selected (depressed). You are ready to create the line that defines the top of the profile. The cue prompts you to indicate the start of the line. For both ends of this line you will use the Infer Point option to indicate Cursor Locations.

565 Select the location for the start of the line as shown in the figure below. Looking at the text fields that move with the cursor, make the line start at approximately XC=8, and YC=20. The exact location does not matter.

The graphic input boxes on the screen change to Length and Angle and the Parameters icon in the upper left corner of the screen is depressed. You will not enter values here, but they give you a good idea as to the approximate length and angle of the line you will create. Locate the end of the line, approximately as shown below. Use Cursor Position, and watching the length and angle boxes, make the line approximately 70 millimeters long and at about 20 degrees.

When you are creating curves in Profile, you can click MB2 at any time to break the string. However, you do not need to in this case - you can just go on to the next step.

Sketch Geometry Creating the First Arc Next, you will create the arc starting at the end of the line just created.

566 Switch to the arc creation mode. Choose the Arc icon

in the upper left corner of the graphics screen.

The system will try to make the arc either tangent to the line, or perpendicular to the line. It depends on how you move away from the line end. It depends on which quadrant of the circle-X symbol you move through as you move to where you want the arc to end. Without selecting a location, move the cursor around the screen. Move it past the end of the line, and then move away from it in a different quadrant. Notice the results. Move the cursor past the end of the line, and this time exit to the right. Watching the parameter values (as you move the cursor), indicate the end of the arc such that it has an approximate radius of 10, and an approximate sweep angle of 160.

Notice that after creating the arc, the symbols where the line and arc join.

The solid square indicates that a Coincident constraint has been applied. The circle indicates that a Tangency constraint has been added. This means that if you move the line or arc, they will always share end points, and will always be tangent to each other.

Sketch Geometry Creating the Next Line Notice that after creating the arc, that the Line option was automatically selected.

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Check to make sure that the Line icon

is indeed selected (depressed).

Create the lower line of the profile. Make sure you see the Tangent symbol displayed, and make the line approximately 70 millimeters long.

Sketch Geometry Creating the Next Arc This time you will change to arc creation by a different method. Click-Drag-Release MB1. The Arc icon (in the upper left corner of the graphics screen) depressed.

should now be

Make sure you have the correct direction for the arc, by passing over the end of the line, and exiting the circle-X symbol to the left.

Select the start of the first line you created, to close off the profile.

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There should be Tangent and Coincident symbols at all ends of curves. If not, you will create the missing ones later.

Sketch Geometry Creating the Circles Change to Circle creation by choosing the Circle icon. Make sure the Circle by Center and Diameter icon

is selected (depressed).

Indicate a location for the center of the first circle, and then drag its size so it looks similar to that shown below: Do NOT try to locate it at the center of the end arc. In other words, do not make it concentric with the end arc.

Create the second circle in the same manner. Again do NOT try to make it concentric with the end arc.

569

Cancel Circle creation by choosing the Circle icon. Exit the Sketcher by choosing the Finish Sketch icon.

Sketch Geometry Extruding the Sketch to Make a Solid A sketch may be revolved, extruded, or swept along a guide (path). These steps are a brief description of how to extrude a sketch into a solid body. Extrusions are explained in detail in the Feature Modeling CAST course. You want the solid to be on a layer reserved for solids. Make layer 10 the Work Layer, and leave layer 21 Selectable Enter 10 in the Work Layer toolbar and press Enter.

Choose the Extruded Body icon the menu bar.

or choose Insert

FormFeature

Select any of the sketch curves. All the curves in the sketch will highlight. OK the selection. Choose Direction_Distance. The Plane Normal icon should be selected. If not, choose it. If the arrow is NOT pointing up, choose Cycle Vector Direction. OK the dialog. Enter a Start Distance of 20.0, and an End Distance of 32.0.

Extrude from

570 Leave all other values set to 0.0, and OK the dialog.

Cancel the Extruded Body dialog.

Constraints Now would be a good time to add any constraints (rules) that were not applied as you created the curves. For example, the lines should be tangent to the end arcs (at all four locations), and you want the circles concentric with the end arcs.

Constraints Adding a Tangent Constraint Double-click on any of the sketch curves, to activate the sketch. The solid is displayed on top of the sketch curves.

Choose the Create Constraints icon. Check the constraint symbols to see if there are any missing Tangent constraints. If there are any, select the arc, and then select the line that should be tangent. Choose Tangent icon

from the toolbar in the upper left corner of the screen.

In turn, wherever else there is a missing tangency constraint, select the arc and then the corresponding line, and apply a tangent constraint.

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Choose Update Model icon.

Constraints Adding a Concentric Constraint Choose the Create Constraints icon

.

Select one of the end arcs and its corresponding circle. Choose the Concentric icon. With the sketch circle moved, you can now see the hole in the solid. Do the same to the other arc/circle pair.

Cancel Create Constraints by choosing the Create Constraints icon MB3 Cancel, or by using Esc (on Windows only). Choose the Update Model icon.

, or by using

572

The holes in the solid are now updated.

Replacement Geometry You have found that this part interferes with another part just below it. You decide that you need an arc instead of the bottom tangent line in the sketch.

You are going to create that replacement arc, and then update the solid.

Replacement Geometry Creating an Arc The sketch should still be active.

Choose the Arc icon. This arc must start and end at the lower ends of the end arcs on both ends of the bottom line.

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Make sure Arc by 3 Points icon is depressed. For the start of the arc, select the lower end point of the right arc. For the end of the arc, select the lower end of the left arc. For the point on the arc, select a location so the arc looks somewhat like what is shown below. Make sure there are NO constraint symbols displayed (except for the two Coincident constraints at each end of the arc).

Cancel Arc creation.

Replacement Geometry Editing a Defining String The defining string for the solid still includes all the original curves in the sketch. You need to tell the system to use the new arc instead of the original lower line.

Choose the Edit Defining String icon. With the Edit String dialog displayed, and EXTRUDED(4) selected on the dialog, shiftselect the line, and select the arc you just created. The screen should now look like the following:

574 OK the Edit String dialog. Choose Update Model icon. Choose the Orient View to Model icon.

Replacement Geometry Deleting a Sketch Curve Now that the line is no longer used by anything (the extrusion specifically), it can be deleted.

Choose the Delete icon

or choose Edit

Delete from the menu bar.

The Sketcher Delete dialog is displayed. Select the line that is no longer being used by the extrusion.

OK the dialog.

Choose the Orient View to Sketch icon.

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Replacement Geometry Creating More Tangency Constraints You realize you need the end arcs and the arc you just created to be tangent.

Choose the Create Constraints icon. Select the right end arc (near the shared end point with the new arc), and then select the new arc you just created. Select it near the shared end point also. By selecting the curves in this manner, there will be no major changes when the tangency is applied. Choose Tangent icon

from the toolbar in the upper left corner of the screen.

Select the left end arc, and then select the new arc. Choose Tangent icon.

Cancel Create Constraints. Exit the Sketcher by choosing the Finish Sketch icon. This also updates the model.

Replacement Geometry Creating Lines to Control the Angle of the Part

576

Before you create the size Constraints, you need to create two more lines for creating an angle dimension and for controlling the length of the part. Activate the sketch. First you need a line between the arc centers.

Choose the Line icon. Select the lower left arc center (watch for the arc enter point symbol). Select the upper right arc center. Next you need a horizontal reference line through the lower left arc center. Make sure you indicate locations such that you see the horizontal symbol prior to creating the line.

Select the lower left arc center. Select a location to the right of the lower left arc center, and make it horizontal. Cancel Line creation.

Replacement Geometry

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Converting Sketch Curves to Reference When the entire sketch is selected to create an extruded feature (as you did here), the system will use ALL the curves in the sketch - even if they were added after the feature using the sketch was created. In this case, the system will not be able to decide how to handle the added curves. You need to tell the system that the two new lines just created are NOT to be used for the extrusion. This is done by converting the curves to Reference.

Choose the Convert To/From Reference icon. On the Convert To/From Reference dialog, make sure the Reference switch is on.

Select the two new lines you just created. OK the Convert To/From Reference dialog.

Reference Curves are displayed as grey phantom curves.

Size Constraints Now you need to add some rules to control the exact sizes and orientation of the part. This is done with Dimensions.

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When viewing the sketch, Dimensions in a sketch look like drawing dimensions, but they actually control the sketch geometry. By changing a Dimension value in a sketch, the sketch geometry will change accordingly.

Size Constraints Setting Some Preferences Before you create some dimensions, you want to set the preferences, so there is only one decimal place displayed. Choose Preferences

Sketch.

Enter 1 in the Decimal Places field.

OK the dialog.

Size Constraints Creating the Dimensions You will now create the dimensions that are needed to control the size and orientation of the geometry.

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Choose the Dimensions icon.

You can select the icon for the dimension type you want to create, or you can use the Inferred method. Using the Inferred method, if more than one type of dimension can be created from what you select, the location of the dimension text will control the type that will be created. The Status Line tells you what will be created.

Size Constraints Creating a Constraint for the Length of a Line First create the dimension that will control the length of the angled reference line. You need the distance between the two circles to be 70 mm. With the Inferred icon active, select the angled reference line. Move the cursor around the screen and notice the different dimensions you can get. Notice the Status area as you move the dimension text.

Move the text until the Status area reads Parallel Dimension (as above), and locate it.

You can move a dimension by prehighlighting it, holding down MB1, moving it, then releasing MB1.

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Size Constraints Entering the Desired Value Notice that an expression is created and its current value is now highlighted in the Constraint dialog. This means you can now enter a new expression name and/or a desired value.

Type in a value of 70.0 and press Enter.

Notice that the dimension and the length of the line both changed. And the circle at the right end of the line moved, as well as the concentric arc.

Size Constraints Creating the Angle Dimension Now you will create the angle dimensional constraint that will control the orientation of the outline. You want the angle between the two reference lines to be 40 degrees. The Dimensions dialog should still be active, and the Inferred method selected. Select the horizontal reference line in its right half - but do not select its end point.

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Move the cursor about the screen. Notice it will create a Horizontal Dimension. Do NOT locate it yet. Now select the angled reference line in its right half, but NOT at its end point. Notice the Status area now reads Angular Dimension. Locate the dimension. In the Current Expression area of the dialog, enter a value of 40.0 and press Enter.

Size Constraints Creating the Radius Constraints You will now create the dimensional constraints to control the radii of the three arcs in the outer profile.

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The Dimensions dialog should still be active, and the Inferred method selected. Select the lower left arc (near the WCS). Do NOT select it at its center or its end points. Locate the radius dimension text. Enter a 26.0 value for this constraint, and press Enter. Create a similar constraint for the arc at the upper right end, with a value of 15.0. Create another radius constraint for the large fillet (between the two arcs you just constrained). Use a value of 100.0 for this one.

Size Constraints Creating the Diameter Constraints You will now create the dimensional constraints to control the diameter of the two circles at each end of the profile.

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The Dimensional Constraints dialog should still be active, and the Inferred method selected. Select the lower left circle. The Status area should read Diameter Dimension. Locate the dimension text. Enter a value of 22.0 and press Enter. Select the upper right circle. Enter a value of 16.0 and press Enter.

Cancel the Dimensions dialog.

Size Constraints Updating the Part Notice that the part is not fully constrained yet, even with these dimensions. (It can still be moved around on the sketch plane.) However, it has been sufficiently constrained to satisfy the design intent, so you can now update the solid.

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Choose the Orient View to Model icon. Exit the Sketcher by choosing the Finish Sketch icon. Make layer 10 the Work Layer, and layer 21 Invisible.

Close the part file.

Working with Sketches In this lesson, you will work with more of the sketch functions and their capabilities. You will learn more about creating constraints. You will also learn about: examining constraints removing constraints setting and changing sketch preferences mirror constraints conflicting constraints positioning a sketch reattaching a sketch creating associative points extracting existing curves into a sketch

Working with Sketches Open part file skt_work_1.prt from the skt subdirectory, and start the Modeling application. Choose the Open icon.

585 Key in skt_work_1 in the File Name field, then OK the dialog. Or you can doubleclick on the file name in the list. Choose the Modeling icon

or choose Application

Modeling

This bottle that was modeled by Creating a series of related sketches. Creating a Through Curve Mesh free form feature using the sketches. Adding a boss on the top. Blending some of the edges. Hollowing the solid.

Working with Sketches Creating the Sketch You have decided that the bottle needs more section control in the middle - where the datum plane is. You are going to create a new sketch to do that. You will completely constrain the sketch, then you will add that new sketch to the definition of the free form feature. You will create this sketch on layer 21. Change the work layer to layer 21. Enter 21 in the Work Layer field, then press Enter.

Choose the Sketch icon

or choose Insert

Sketch.

586 The system assumes that you want the sketch on the current XC-YC plane, so it displays a datum plane, two datum axes, and the proposed sketch coordinate system on the XC-YC plane. Create a sketch named MID-SECTION, using the datum plane as the sketch plane (with the Z axis pointing up). Use the datum axis parallel to the XC axis as the horizontal reference. Change the sketch name from SKETCH_002 to MID-SECTION by highlighting the current name, then keying in the new name. With the Sketch Plane icon active, select the datum plane. Make sure the Z axis is pointing up. If not, double-click on it to reverse the direction. To define the horizontal direction, select the datum axis that lies along the XC axis. Make sure the sketch X axis is pointing to the right. Choose the OK icon.

The Sketch Geometry In order to create an additional section profile for the bottle, you will create a rectangle, two arcs, and one fillet. You will then add some constraints This will comprise one quadrant of the entire sketch geometry. You will then use Mirror to complete it.

The Sketch Geometry Setting the Layers

587 You will not need to refer to the solids, existing sketch geometry or the solid for some time, so make those layers Invisible. Leave layer 21 the Work Layer and make all other layers Invisible. Choose the Layer Settings icon Select the category ALL. Choose Invisible. OK the Layer Settings dialog.

or choose Format

Layer Settings.

The Sketch Geometry Creating the Rectangle First you need to create a rectangle that will be the limits of the upper right quadrant of the finished sketch.

Choose the Rectangle icon. Using WCS values, indicate the lower left and upper right corner of the rectangle. Make it 30 mm long by 15 mm high.

The Sketch Geometry Creating the Two Arcs The first arc will help define the back of the bottle.

Choose the Arc icon. Make sure the Arc by 3 Points method is active. Indicate the following three locations. Do not necessarily try to make it tangent to the top line, but make it fairly "flat", as below: You may wish to use Cursor Location for points 2 and 3, but make sure to select the existing line end point for point 1.

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Use MB2 to Break String (if necessary). Indicate the following three locations for the second arc. Again, do not necessarily try to make it tangent to the vertical line.

Fillets in Sketches Next you need to create some kind of blend between the two arcs just created. You will use a Fillet.

Fillets are covered in more detail later. Choose the Fillet icon. An icon appears in the upper left corner of the graphics screen.

This is for you to tell the system whether or not you want it to trim the input curves (the curves being filleted).

589 A text entry field appears on the graphics screen for entering a desired radius for the fillet.

If you do not enter a radius, you will be able to drag the size of the fillet. That is what you are going to do here.

Fillets in Sketches Creating the Fillet You can create a Fillet between any two curves (other than a spline) or lines. As the fillet is created, the system will create tangency constraints for you. Depending on whether or not you have trimming turned on, the system will also create Point on Curve or Coincident constraints. If you key in a radius an create multiple fillets, the system will create Equal Radius constraints. This all depends on a setting that will be discussed later. For the fillet you are about to create, you do not want to specify a radius value. But you do have a feel for the relative size of the fillet.

In the fillet creation process, you can enter an exact radius at any time.

Fillets in Sketches Selecting the Geometry It is not necessary to select the curves in a counterclockwise direction, as it is when you are not in the sketcher. Select the arc on the right.

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Select the top arc.

Move the cursor around the screen, and notice how you can dictate its size and quadrant. Select a location that will produce a fillet with an approximate radius of 5, so it looks something like below:

You could key in an exact value at this point, if desired. You have completed the sketch geometry for the upper right quadrant.

Choose the Fillet icon Windows only).

to cancel the fillet function. (You can also use Esc - on

Constraints As you noticed (by the symbols on the screen), the system created some constraints as you created the curves. You have control over which constraints MAY be applied.

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Choose the Infer Constraint Settings icon.

For any icon that is depressed, that type of constraint is available to be applied as you create curves. The default settings work quite well for most situations. You will leave them as they are for now. Cancel the Infer Constraints dialog.

Constraints Constraint Display By default, when a sketch is active, some of the constraints are always displayed (Coincident, Point on Curve, Midpoint, Tangent, and Concentric). But you have control over this. Sometimes, if the geometry display is too small, constraint symbols may not be displayed. You can zoom up on the area to see them if this is the case. You can also turn off Dynamic Constraint Display on the Sketch Preferences dialog. Choose the Show All Constraints icon.

Notice that now the horizontal and vertical symbols are displayed as well as those already displayed.

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Choose the Show All Constraints icon constraints.

to return to the previous display of

Choose the Show No Constraints icon.

Choose the Show No Constraints icon constraints.

again to return to the standard display of

More About the Geometric Constraint Symbols

This list shows the symbol that represents each geometric constraint. Symbol Constraint Type

Fixed

Point on Curve

Horizontal

Point on String

Vertical

Midpoint of Curve

Parallel

Equal Length

Perpendicular

Equal Radius

Tangent

Constant Length

Concentric

Constant Angle

Coincident

Mirror

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Collinear

Slope of Curve

Uniform Scale

Non-uniform Scale

Associative Trim

Associative Offset

Examining the Constraints You can also examine the constraints much more closely.

Choose the Show/Remove Constraints icon. The Show/Remove Constraints dialog displays.

Examining the Constraints Using Show/Remove Constraints Make sure All in Active Sketch is on.

594 By default, only the constraints explicitly created by you or the system are listed on the dialog. By using the Constraint Type options you can see Explicit, Inferred, or Both types of constraints. Any line created within the snap angle (by default set to 3 degrees) of horizontal or vertical will be assigned a horizontal or vertical geometric constraint. Since Rectangle creates two horizontal and two vertical lines, the system assigned constraints to each of the 4 lines that make up the rectangle. Tangency constraints were also automatically added for the fillet you created, and possibly between the arcs and the fillet. If those between the arcs and fillet were not created, you will create them later. Select each constraint in the list, and notice what is highlighted on the graphics screen.

Examining the Constraints Selected Object Choose Selected Object (only to remove the information from the list window). Move the cursor over the curves in the graphics window (without selecting anything) and notice the prehighlighted curves. Any curve the cursor is over will be prehighlighted, as well as all the curves it is constrained to. Select the fillet.

Notice the information on the dialog.

Cancel the Show/Remove Constraints dialog.

Constraints

595 A constraint can be a fixed characteristic of a sketch object or a fixed relationship between one or more objects. For example, a line can be constrained to always be vertical, or two lines may be constrained to be parallel or perpendicular.

Choose the Create Constraints icon. The cue prompts you to select curves to create constraints. For information about the types of geometric constraints that can be created in Unigraphics NX, select the link below.

Types of Geometric Constraints

Here is a complete list of all the geometric constraints available in Unigraphics NX: All objects referenced that are not in the sketch plane are projected onto the sketch plane using the plane normal. Fix

Defines fixed characteristic for geometry, depending on the type of geometry selected.

Coincident

Two or more points have the same location in the sketch plane.

Concentric

Two or more arcs have center points located at the same place in the sketch plane.

Point on Curve

A point as lying on a curve or edge.

Point on String

A point as lying on a string of curves.

Midpoint of Curve A point as coincident with the midpoint of a curve or edge. A line that is horizontal - parallel to the sketch X axis. Horizontal Vertical

A line that is vertical, parallel to the sketch Y axis.

Parallel

Two or more lines that are parallel to each other.

Perpendicular

Two lines that are at a 90 degree angle to each other.

Tangent

Two objects that are tangent.

Equal Length

Two or more lines that have the same length.

Collinear

Two or more lines are parallel and on the same axis.

Equal Radius

Two or more arcs or circles that have the same radius.

Constant Length

The line has a constant length.

Constant Angle

The line has a constant angle.

Mirror

Two objects that are a reflection (mirror) of each other around another line.

Slope of Curve

The spline is tangent to a curve at this point.

Scale, Uniform

The spline is constrained to scale in both the X and Y directions as its ends are moved.

596 Scale, NonUniform

The spline is constrained to scale only along the axis of its end points.

Associative Trim

The spline has been trimmed using Curve Trim, with the associate switch on.

Associative Offset The curves have been offset from extracted curves.

Constraints Creating a Fixed Constraint In order to better track the progress you make as you constrain a sketch, it is a good practice to position at least one point first. This can easily (and temporarily) be done by fixing one of the sketch points. With the Create Constraints icon active, select the lower left end point of the rectangle. (It does not matter which line you select, since their ends are coincident.) Icons for the constraints available for what you have selected are displayed in the upper left corner of the graphics screen. In this case there is only one type available.

Choose the Fixed icon.

The symbol for Fixed will not show on the screen unless you turn on Show All Constraints. Notice, however, that there are no yellow arrows on the point you just fixed.

More About: The Fix Geometric Constraint

This table shows what is "fixed", depending on the type of geometry selected when the Fix constraint is applied. Geometry selected

What is fixed

Point

The location

597 Line

The angle

Arc or elliptical arc endpoint

The location of the endpoint

Arc, elliptical arc, circle, or ellipse center The location of the center Arc or circle

The radius and center

Ellipse

The radii and center

Elliptical arc

The radii and location of the center

Spline End Points or Defining Points

The location

The Degree-of-Freedom (DOF) Arrows

The DOF arrows displayed on a sketch point show the direction(s) in which that point is still free to move. The point is free to move in both the X and Y directions. The point is free to move only the X direction. The point is free to move only in the Y direction. The point is free to rotate. These arrows show you the directions in which you need to constrain each point. As you constrain the sketch, DOF arrows are removed. When the sketch is fully constrained, all DOF arrows will be gone. It is important to remember that sketches DO NOT need to be constrained at all. Sketches can be used for defining features regardless of how much or how little they are constrained. Constraints only need to be applied where you want to have control over the design. For more information about how DOF arrows are assigned to newly created geometry, select the link below.

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Degree-of-Freedom Arrows on Newly Created Geometry

Each type of curve has different degree-of-freedom (DOF) arrows when it is first created.

Lines are constrained at their endpoints.

Arcs are constrained with a specified radius, arc center, and arc endpoints.

Circles are constrained using the center point, and a radius or diameter.

Ellipses are constrained using the center point, the major and minor radii, and the rotation.

599 Partial ellipses are constrained using the center point, the two endpoints, and the rotation.

General conics are constrained using the two endpoints, and the anchor point.

Splines through points are constrained using their defining points and endpoints.

Splines by poles are constrained using their endpoints.

The Degree-of-Freedom (DOF) Arrows Display of DOF Arrows You can turn the display of the DOF arrows on and off with the Display DOF Arrows option on the Sketch Preferences dialog.

It is usually a good idea to have your DOF arrows displayed while constraining, so that you know which sketch points are unresolved. As you work on this activity, watch the DOF symbols disappear as you apply constraints.

Evaluating the Sketch

600 The system evaluates the sketch each time you add or remove constraints, because the Delay Evaluation icon

is not depressed (is off).

When it is on, you would choose the Evaluate Sketch icon

to perform an evaluation.

Evaluating the Sketch Creating the Tangent Constraints In addition to the Horizontal and Vertical constraints you just examined, you also want the two arcs to be tangent to lines in the rectangle (if they have not already been created earlier). If needed, with the Create Constraints icon active, select the large top arc (but not at one of its control points). Select the top horizontal line. Choose the Tangent icon. If needed, select the right arc. Select the right vertical line. Choose the Tangent icon. The sketch should now look like:

Dimensions

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Dimensions are scalar values or expressions that define the measure of some geometric object, such as the length of a line or radius of an arc. These constraints look similar to the dimensions that you see on a drawing. But, in contrast to drawing dimensions, these actually control the geometry.

Dimensions Creating Dimensions To meet the design intent, you must constrain the size of the base rectangle. You need to add two dimensional constraints: one for the length, and one for the width.

Choose the Dimensions icon. The Dimensions dialog is displayed. The cue prompts you to select objects to dimension or edit.

For more information about the types of dimensional constraints that can be created using these icons, select the links below.

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Types of Dimensions

Here is a complete list of all the types of dimensions available in Unigraphics NX. Inferred - This lets you create a variety of constraints, based on the geometry you select and how you locate the dimensions. Horizontal - Creates a dimension parallel to the sketch X axis. Vertical - Creates a dimension parallel to the sketch Y axis. Parallel - Creates a dimension that is parallel to the distance between the two selected points. Perpendicular - Creates a perpendicular dimension between a line and a point. Diameter - Creates a dimension that is a diameter of a selected arc or circle. Radius - Creates a dimension that is a radius of a selected arc or circle. Angular - Creates an angle dimension between two lines, measured counterclockwise relative to the sketch X axis. Perimeter - Creates a constraint that controls the total length of the selected objects.

Dimensions How Dimensions Are Inferred The way you select objects and locate dimensions controls the inferred constraint type that is created.

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If you select... You will get this type of dimensional constraint: L12

Vertical

L2 & L5

Perpendicular

L3 & P1

Perpendicular

L3 & A3

Perpendicular

L3

Horizontal, Vertical, or Parallel, based on cursor location

P4 & A2

Horizontal, Vertical, or Parallel, based on cursor location

P2 & P3

Horizontal, Vertical, or Parallel, based on cursor location

A1

Radius

A2

Diameter

Dimensions Dimension Options There are three ways you can control the display of Dimensions that are available on the Dimensions dialog.

604 1 Text Arrow Placement allows three options. Auto Placement will always try to place the text centered between and inside the extension lines. If it cannot, it will place the text and arrows as the system sees best with the location you indicate. This overrides the Leader Side setting. Manual Placement Arrows In will place the text exactly where you indicate, and will always place the arrows inside the extensions lines. These options also use the Leader Side setting. Manual Placement Arrows Out will place the text exactly where you indicate, and will always place the arrows outside the extension lines. These options also use the Leader Side setting. 2

Leader Side allows two options. Leader From Left Leader From Right Text Height allows you to specify how high the text characters will be.

3

If you enter a new text height the height ALL of the constraints in the current active sketch will change.

Dimensions Creating a Vertical Dimension With the Dimensions dialog active, select the left vertical line (avoiding the endpoints).

Move your cursor to the left and you will see a rubber-band dimension value display. (The value of your dimension will be different.)

Notice that, because you selected a vertical line, the system inferred that you wanted a vertical dimension.

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You could also have used the Vertical icon

to create this dimension.

Click the left mouse button to place the dimension. (The dimension includes an expression name and number.) This side of the rectangle must be 14.45 mm long. Key in 14.45 in the right-hand field under Current Expression, then press Enter.

The geometry is resized to fit the new dimension value. (Fit the view, if you need to.) Notice also that another DOF arrow has been removed. Since the bottom end of the line is fixed, and it is vertical, now that its length is constrained, its upper end is now fully constrained.

Dimensions Creating a Horizontal Dimensional Constraint The length of the rectangle must be 27.381 mm long. Using the same method, use a horizontal dimensional constraint to constrain the length of the rectangle, to a length of 27.381.

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Dimensions Changing the Text Height You would like the text height of the dimensions to be a little smaller. On the Dimensions dialog, in the Text Height field, key in 2.0 and press Enter. Notice that the height of all the dimensions changed. Later, if you wish, you can move these dimensions to make them more readable.

Dimensions Creating the Radius Dimensions If you look at the remaining DOF symbols, you see that they only remain for the arcs and the fillet. All you need to do to fully constrain the sketch now is to add three more dimensions. The radius of the top arc must be 68.0 mm. With the Dimensions dialog active, and the Inferred icon active, select the top arc. Locate the dimension on the graphics screen. Change its value to 68.0.

The radius of the right arc must also be 68.0 mm. Select the right arc. Locate the dimension on the graphics screen. Change its value to 68.0 also.

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The radius of the fillet must be 4.8 mm. Select the fillet. Locate the dimension on the graphics screen. Change its value to 4.80.

Notice that all the DOF symbols are gone, and the status area shows:

Sketch Preferences The Sketch Preferences dialog has several settings that may be of interest to you. It allows you to control many things when working with sketches.

Sketch Preferences Sketch Preferences - Snap Angle Choose Preferences

Sketch.

608 Snap Angle controls whether or not some constraints are applied.

If you try to create a line, and it is within the snap angle of being horizontal or vertical, it will have a horizontal or vertical geometric constraint applied to it. Also, if a line or arc is created, and it is within the Snap Angle of being tangent to another line/arc, a tangent constraint will be applied. The default is 3.0 degrees, and this seems to work fine for most general work.

Sketch Preferences Sketch Preferences - Decimal Places There are four items on the Sketch Preferences dialog that control the display of dimensions:

If you change any of these settings while a sketch is active, all the dimensions in that sketch will change. When no sketch is active, the new setting affects the next sketch that is created. Decimal Places allows you to control the number of decimal places the system will use to display the value of a constraint.

Sketch Preferences Sketch Preferences - Dimension Label Dim. Label allows you to control what is displayed in the dimensional constraints. It offers three settings:

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Change the Dim. Label to Name and Apply the dialog. Only the expression names are displayed. Change the label to Value and Apply the dialog. Now only the expression values are displayed. Change the Dim. Label back to Expression, and Apply the dialog. Sketch Preferences Sketch Preferences - Text Height

Text Height allows you to change the size of the text in the active sketch. Enter 3.0 for the Text Height.

OK the dialog. Notice that the text size changed for all the dimensions.

Mirror in Sketch

610 Mirror in the Sketcher allows you to create "mirror-image" geometry about a selected line. The mirrored geometry is associated with the selected geometry. Then, if the original geometry changes, so will the mirrored geometry.

When you do this, the line selected as the mirror line will be converted to a reference curve.

Mirror in Sketch Creating the Mirror Geometry You are now ready to create the mirror geometry to complete the sketch.

You will first mirror about the lower horizontal line, then about the left vertical line, to create the total profile of the bottle in this plane. The sketch MID-SECTION should still be active, if not, Activate it. Choose the Mirror icon. You get the Mirror Sketch dialog.

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Mirror in Sketch Selecting the Geometry The are two steps in this procedure: select the Mirror Centerline, and then select the Mirror Geometry. Select the lower horizontal line as the Mirror Centerline.

Use MB2 to advance to the next selection step. Select the two arcs and the fillet as the Mirror Geometry.

Apply the dialog.

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Mirror in Sketch Creating the Next Mirror Select the left vertical line as the Mirror Centerline.

Use MB2 to advance to the next selection step. Select the four arcs and the two fillets as the Mirror Geometry.

OK the dialog.

Mirror in Sketch Converting the Two Lines to Reference The mirror procedure converted two of the lines in the rectangle to reference. Since you do not want any of the rectangle lines to be used to create model geometry, you need to convert the two remaining lines of the rectangle to Reference.

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Choose the Convert To/From Reference icon. Make sure the Reference switch is on. Select the top horizontal and right vertical lines of the rectangle. OK the Convert To/From Reference dialog.

Mirror in Sketch Deleting Constraints

You can use the Delete icon

to remove both Constraints and Dimensions.

You can select the constraint or dimension and then choose the Delete icon, or you can choose the icon first and then select the constraint or dimension. Constraints can also be removed by using the Show/Remove Constraints dialog. On the Show/Remove Constraints dialog you would choose the constraints you want removed, and choose one of the two "remove" options.

Dimensions can also be removed by using the Dimensions dialog. Using the Dimensions dialog, you would select the dimension and then choose the Remove Highlighted option.

Mirror in Sketch

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Removing the Fixed Constraint Earlier, you created a Fixed constraint to the lower left corner of the rectangle. This was so you could see the progress as you assigned constraints. Now you need the sketch positioned properly for the model. To do that, you first need to remove the fixed constraint.

Choose the Show All Constraints icon

to display the Fixed constraint.

Notice all the mirror constraint symbols.

Choose the Select Constraints icon

on the Selection toolbar.

Select the Fixed constraint symbol on the screen.

Choose the Delete icon. Choose the Show All Constraints icon

to simplify the display.

Mirror in Sketch Changing the Layer Settings Now you need to be able to select the datum axes on layer 62 for positioning the sketch. Leave layer 21 the Work Layer and make layer 62 Selectable. Choose the Layer Settings icon Select the layer 62. Choose Selectable. OK the Layer Settings dialog.

or choose Format

Layer Settings.

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Mirror in Sketch Creating Point on Curve Constraints You now need to add two more constraints to control the positioning of the sketch on the model. This could be done by using the Create Positioning Dimensions icon, but in this case you are going to add more Constraints.

Choose the Create Constraints icon. You now see many DOF symbols on the graphics screen because the sketch is no longer located (fixed) on the sketch plane The status line tells you that you will need two constraints to fully constrain the sketch.

Mirror in Sketch Selecting the Geometry You want the center of the sketch geometry to be located directly above the intersection of the two datum axes. Select the end point at the left end of the lower horizontal reference line.

Select the vertical datum axis.

616 The system will allow you to create only one type of constraint.

Choose on the Point on Curve icon. Do the same as you just did, but use the lower end of the left vertical reference line (which now should lie on the vertical datum axis) and the horizontal datum axis.

The sketch is once again fully constrained, but it is now positioned correctly in model space. It is now ready to be included in the definition of the through curve mesh feature that defines the basic shape of the bottle. Cancel the Create Constraint function. Choose the Finish Sketch icon

to exit the Sketcher Task Environment.

Mirror in Sketch Changing the Layer Settings Now you need to be able to select the solid geometry on layer 10 and the sketch geometry on layer 23. You no longer need the reference geometry on layer 62. Make layer 10 the Work Layer, make layer 62 Invisible, and make layers 21 and 23 Selectable. Choose the Layer Settings icon Select the layer 10. Choose Make Work. Select the layer 62. Choose Invisible. Select the layer 23. Choose Selectable. OK the Layer Settings dialog.

or choose Format

Layer Settings.

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If the TFR-TRI view does not display, change the view to the TFR-TRI. Choose Replace View

TFR-TRI, using MB3 in the graphics area.

Mirror in Sketch Reordering the Sketch Feature Before you can use the sketch to help define the bottle shape, the sketch must exist before the free form feature in time stamp order. Since your sketch was created AFTER the free form feature, you need to Reorder the features. This can be done several ways. The following is one of them. Display the Model Navigator. Find the Through Curve Mesh feature in the navigator and select it.

Using MB3 on the selected node on the navigator, choose Reorder After SECTION:SKETCH(40).

MID-

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The sketch you created can now be used to help define the shape of the bottle.

Mirror in Sketch Adding a Defining String to the Through Curve Mesh Feature You will now edit the Through Curve Mesh Feature by adding the sketch you have just finished as an additional Primary String. Double-click on THROUGH_CURVE_MESH(18) in the Model Navigator. Choose Add String. Select Primary #2 (the sketch just above the sketch you created) as the string to be added after. Select the new sketch at the exact curve and location shown below:

OK the dialogs until the part updates. The new sketch you created is now part of the definition of the through curve mesh feature.

Changing Dimensions Once you have created a dimensional constraint, there are a number of ways that you can change it. One way is to change its value.

619 When the Dimensions dialog is displayed, the dimensions you created are displayed in the dialog box as expressions.

You edit dimensions in the Current Expression fields. You can change the expression name in the left field, or change its value in the right field. You can also use the slider bar to change the value of the expression.

The easiest way to edit a dimension is by simply double-clicking on the dimension on the graphics screen, without using the Dimensions dialog.

Changing Dimensions Editing a Dimensional Constraints Now you have decided that you want the middle of the bottle (where you created the sketch) flatter in the front and back of the bottle. There are a number of ways that you can change a dimension. In this part of the exercise you are going to do it without using the dialog. Double-click on any curve in the MID-SECTION sketch to activate the sketch. You want to change the radius for the front and back of the sketch from 68.0 to 120.0. Double-click on the dimension for the top arc.

620 Notice the dynamic input fields. You can enter a new value, or a new expression name, or both. Enter a value of 120.0 in the value (right) field, and press Enter. Notice that all four quadrants changed to a flatter, more square shape.

Changing Dimensions Updating the Part To better see the effect of what you have done, you will update the part while in the trimetric view, and with the part shaded.

Choose the Orient View To Model icon. If you have it available, shade the view. Choose the Shaded icon the graphics area.

or choose Display Mode

Shaded with MB3 in

Choose the Update Model icon. Rotate the view to see the effect of what you have done. Choose the Finish Sketch icon

to exit the Sketcher Task Environment.

Close the part file.

Listing the Expressions Associated with a Sketch If you need to find what expressions are used by any sketch in your part file, you can do so even when the particular sketch is not active. You would choose Information

Expression

List by Sketch.

The cue would prompt you to select a sketch, and the Expressions Information dialog would display all the sketches in the part.

621 If the part file contained many sketches and you wanted to search for a character string, you could filter this list. After selecting a sketch and OK'ing the dialog, the Information window displays the dimensional constraints used in this sketch.

You can use the options on the Information window menu bar to save, copy, or print the information.

Conflicting Constraints Sketch geometry is over constrained whenever there are more constraints than are needed to fully constrain the geometry. In this example all the curves and dimensional constraints that are in conflict are highlighted in yellow.

The status area would inform you that something is overconstrained.

This tells you that this sketch geometry has conflicting constraints. When this occurs the sketch cannot be resolved. The sketch is displayed in the last solved condition. It will remain that way until the overconstrained condition is removed.

622 To do this, you would need to remove some constraints and/or some dimensions.

Conflicting Constraints Opening the Part In this activity you will change the way a sketch is constrained, and in the process create an overconstrained condition. You will then correct that condition. Open part file skt_work_2.prt from the skt subdirectory, and start the Modeling application.

This part is the same as the part you just worked on, except it was saved at the point the sketch was completely constrained, but not yet positioned correctly.

Conflicting Constraints Activating the Sketch First you need to activate the sketch you want to work with. Double-click on any of the sketch curves.

You can also activate a sketch by choosing the Sketch icon, and then selecting the sketch you wanted to activate in the Sketch Name field. You can also double-click on the desired sketch in the Model Navigator.

Conflicting Constraints Sketch Preferences - Layers

623 When a sketch is activated, the layer on which the sketch resides is automatically made the Work Layer. All other layers remain as they are. When the sketch is deactivated, what happens is governed by a Sketch Preferences settings:

When Maintain Layer is on, the Layer Settings will return to the settings prior to activating the sketch. When it is off, the Work Layer will remain that of the sketch when it is deactivated.

Conflicting Constraints Sketch Preferences - View When a sketch is activated, the view changes the orientation of the plane of the sketch, or remains as is, depending on the setting on the Sketch Tools dialog.

When this is on, the view orientation will remain that of the sketch view when the sketch is deactivated.

Conflicting Constraints Retaining Dimension Display When a Sketch is Deactivated Normally, when you exit a sketch, the dimensions are not displayed. However, you can keep them displayed after the sketch is deactivated by using Retain Dimension Display on the Sketch Tools dialog.

If you deactivate a sketch (by leaving the Sketcher Task Environment or by activating a different sketch) with this switch on, although the sketch is inactive, the dimensions are still displayed.

Conflicting Constraints

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Creating More Dimensions Instead of using half-width and half-height dimensions to control the overall size you would prefer full width and height constraints. Using the Parallel dimension type, create an overall length (parallel) dimension between the two points indicated:

Choose the Dimensions icon. Choose the Parallel icon. Select the two point indicated above. Locate the dimension text.

Notice that the new constraint and the old "half-width" constraint turn yellow. Notice that the status area tells you there is an overconstrained condition.

This is because the left half of the sketch geometry is a mirror of the right half - and the right half is completely constrained. So the left half is also completely constrained. The new dimension is more than needed, so the sketch is now overconstrained.

Conflicting Constraints Creating Another Dimensional Constraint You can leave the sketch over constrained as you create this next dimension.

625 Create another parallel dimension for the "height" of the sketch. Use the points as shown below:

Notice that now all four dimensional constraints are yellow.

Cancel the Dimensions dialog.

Conflicting Constraints Removing the Overconstrained Condition You do NOT want to leave a sketch in an overconstrained condition, since it will no longer update with any changes you make. You could simply delete the old "half-height" and "half-width" constraints. But in this case you would like to retain them for future reference. You are going to convert them to reference dimensions, the same way you converted curves to reference earlier.

Choose the Convert To/From Reference icon. Make sure the switch on the Convert To/From Reference dialog is set to Reference. Select the two "half" dimensional constraints, and OK the dialog.

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Notice that the converted constraints are now shown in white, and no longer have an expression name. They are simply reference dimensions now - they no longer control anything in the sketch. They are associative though. If the sketch changes in a way that affects any reference dimensions, they will update. If you later converted reference dimensions back to constraints, they would NOT use the old expression name. Choose the Finish Sketch icon

to exit the Sketcher Task Environment.

Close the part file.

Positioning a Sketch As you saw earlier, you can position a sketch by using constraints (such as Point on Curve). You can also position a sketch by using Dimensions. There is yet another way. You can create Positioning Dimensions for a sketch just as you can for any other feature. This is done by choosing the Create Positioning Dimension icon. This will access the Positioning dialog:

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Use of this dialog is considered in detail in the Feature Modeling Fundamentals and Feature Modeling - Additional Topics CAST courses.

Positioning a Sketch Opening the Part In this activity you will position a sketch using the Create Positioning Dimension method. Open part file skt_work_3.prt from the skt subdirectory, and start the Modeling application.

This part is the same as the part you just worked on, except the Fixed constraint has been removed, but the Point on Curve constraints were not created. You can also see that the sketch is not positioned correctly. To make working on it easier, hidden lines have been set to Invisible and smooth edges have been turned off.

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Positioning a Sketch Creating a Horizontal Positioning Dimension You will now create one horizontal and one vertical positioning dimension to correctly locate the sketch on the model. Activate the sketch MID-SECTION. Choose the Create Positioning Dimension icon. Choose the Horizontal icon

on the Positioning dialog.

You can use the arc center of the top of the bottle to position the sketch. Select one of the circular edges at the top of the bottle as the target object.

Use the Arc Center option. Select the leftmost vertical reference line in the sketch as the Sketch curve to be located.

Change the dimension value to 0.0, and OK the dialog.

Positioning a Sketch Creating a Vertical Positioning Dimension Choose the Vertical icon. Select the same arc (as above) and use Arc Center again as the target object.

629 Select the lower horizontal reference line as the sketch curve to be located.

Change the dimension value to 0.0. OK the Create Expression dialog. OK the Positioning dialog. The sketch is now properly positioned on the model.

Choose the Finish Sketch icon

to exit the Sketcher Task Environment.

Close the part file.

Reattach Sketch Just like any other feature, sketches can be reattached to a different Datum Plane or planar face. Reattach Feature can be used for this. It is covered in detail in the Feature Modeling CAST course. There is also a Reattach function within the sketcher. It is accessed by choosing the Reattach icon.

630 The Reattach process includes selecting a Sketch Plane and a directional reference. If there are positioning dimensions used, redefining them is a separate process. It is also covered in this lesson.

Reattach Sketch Opening the Part In this activity you will reattach a the sketch using the Reattach option. Open part file skt_work_4.prt from the skt subdirectory, and start the Modeling application.

This part is the same as the part you created in the previous lesson, but with added positioning dimensions for the sketch location. Also a block with an angled face has been added to the model along with some datum planes. The sketch will be reattached to the angled face. The datum planes have been created and positioned for locating the sketch. Right now, the sketch is located on the current sketch plane: The left circle arc center is positioned vertically on the sketch X axis, using Point Onto Line. The same arc center is positioned horizontally from the sketch Y axis, using a Perpendicular positioning dimension.

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Reattach Sketch Design Intentions You originally created the sketch on a the XC-YC Datum Plane. Since creating and extruding the sketch, you have created a solid model in the part file. You now want the sketch to be attached to the angled face of that solid, and positioned from the two datum planes. Again, the datum planes have been located correctly for positioning the sketch.

Reattach Sketch Activating the Sketch With Select Features turned on (on the Selection toolbar), double-click on any of the sketch curves. Choose the Orient View To Model icon. The sketch dimensions have been blanked to make your work easier.

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Reattach Sketch Reattaching the Sketch Choose the Reattach icon. With the Sketch Plane icon active, select the angled face of the solid.

The Cue Line is asking you to select a horizontal direction, and the proposed sketch X axis is highlighted. What you now select will be used for aligning the X axis of the sketch. Instead of selecting a horizontal reference, you could select the Y axis, and then select something with which to align the vertical (Y) axis. With the sketch X axis highlighted, select the face shown below, in its right half.

Notice the "parallel" symbols on the sketch X axis and the selected face. Verify that the X axis is pointing to the right. If not, double-click on it to reverse its direction. If you need to change its direction completely, just select the vertical face (and make sure you get the face). Choose the OK icon.

Reattach Sketch Deleting the Positioning Dimensions The sketch now lies on the angled face of the part, but its location needs to be redefined. The current Positioning Dimensions need to be deleted, and new ones created.

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Choose the Orient View to Model icon. Choose the Delete Positioning Dimension icon, by clicking on the drop-down arrow.

Select both dimensions.

OK the dialog (or use MB2).

Reattach Sketch Recreating the First Positioning Dimension You will use the angled datum plane as the first positioning reference, and will locate the center of the large arc on the left. Choose the Create Positioning Dimension icon.

Choose the Perpendicular icon. Select the angled datum plane.

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Select the left arc in the sketch, and then choose Arc Center.

Enter a value of 0 and OK the dialog.

Reattach Sketch Recreating the Second Positioning Dimension Choose the Perpendicular icon. Select the "vertical" datum plane.

Select the left arc in the sketch, and then choose Arc Center.

Enter a value of 20.0 and OK the dialog. OK the Positioning dialog.

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Reattach Sketch Finishing the Part Choose the Finish Sketch icon.

The sketch is now associated with the angled face of the part. If that face changes location or orientation, the sketch (and its extrusion) will move with it. Reattach is also available in Modeling. You would use Edit Feature Parameters, and select the sketch. In this process, you have the ability to redefine the dimensions, as part of the Reattach procedure. Close all part files

Using Associative Points You can use non-sketch geometry to create an associative point in a sketch. If the geometry used to create the associative point changes, the point will change also. This is accessed from the Sketch Curve toolbar:

Open the part file skt_work_6.prt from the skt directory, and start the Modeling application.

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These curves are in the two sketches in this part file. They are on separate parallel planes. The bottom sketch is fully constrained. The top sketch is only lacking a position. You want to position the circle in the top sketch to always be directly above the intersection of the reference lines in the bottom sketch. To do this you are going to create an associative point in the top sketch, then make the circle center coincident with it. Then you will edit the bottom sketch and see the location of the top sketch change.

Using Associative Points Creating the Associative Point Activate SKETCH_000, and then return the view to the model orientation. Double-click on any curve in the upper sketch. Choose the Orient View To Model icon. Choose the Associative Point icon.

You get the Point Constructor dialog. You want to use the intersection of the two reference lines in the bottom sketch. Choose the Intersection Point icon

on the Point Constructor dialog.

Select the two reference lines in the bottom sketch.

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An associative point is created at the intersection of the two selected lines. This associative point is in sketch_000, even though it is not in the sketch plane. Cancel the Point Constructor dialog.

Using Associative Points Using the Associative Point Now you need to make the circle in the active sketch coincident with the associative point you created. Create a Coincident Constraint between the associative point, and the circle center. Choose the Create Constraints icon. Select the center of the circle in the top sketch. Select the smart point in the plane of the bottom sketch. Choose Coincident icon.

The circle center now lies directly above the intersection of the two reference lines in the bottom sketch. Change the view orientation to that of the top view. Choose the Create Constraints icon on Windows only).

to turn off the function. (You can also use Esc -

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Using Associative Points Editing the Bottom Sketch Now you are going to change the bottom sketch so the associative point you created will move, and watch the upper sketch change location as the point moves. Use the Sketch Name option to activate SKETCH_001 (the bottom sketch). Change the value of the Dimension p24 to 40.0. Double-click on the dimension named p24. In the text field on the screen, enter a value of 40.0, and press Enter.

Notice that the bottom sketch changed, but the associative point did not yet move. That is because it is in the other (top) sketch.

Watch the upper sketch as you choose the Update Model icon.

The circle is again directly above the intersection of the two reference lines.

Finish the sketch

, Cancel all dialogs and Close the part file.

Adding Extracted Curves to a Sketch There are times when you want to control a sketch's location and other constraints from existing geometry that is not planar and/or not in the plane of the sketch.

639 You can extract associative copies of geometry into the sketch. The associative copies are projected normal to the sketch plane. These extracted curves cannot be constrained because they are already completely located and constrained otherwise by their parent objects (those selected to be extracted). If the parent curves or edges change, the extracted curves in the sketch will update.

Adding Extracted Curves to a Sketch Design Intent In this activity you want to create a web on the end of the extrusion.

You want the curved shape of its top to stay associated with the "groove" in the extrusion. If the "groove" gets wider, you want the web to follow. If you create the arc for the top of the web so that it is associated with the vertical edges of the "groove", you will have accomplished your intent.

640 Adding Extracted Curves to Sketch will allow you to do that.

Adding Extracted Curves to a Sketch Opening the Part Open part file skt_work_5.prt from the skt subdirectory, and start the Modeling application.

This part was created by modeling a block, placing two rectangular pads on its top, and trimming the ends of the part using two free form features. Then a blend and a chamfer were added. You are going to create a sketch, extract some edges into the sketch, and create an arc in the sketch. These curves will define the shape of the web. Then you will extrude the sketch. Lastly, you will edit the parameters of the base block to test what you have done.

Adding Extracted Curves to a Sketch Creating the Sketch Change the Work Layer to 21. Enter 21 in the Work Layer field, and press Enter. Create a sketch using the datum plane for the sketch plane and the bottom face of the solid as a horizontal reference (to the right). You can use the default name for the sketch. After it is created, return the view to that of the model. Choose the Sketch icon. Select the Datum Plane for the sketch plane. Select the bottom face of the solid for a horizontal reference.

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Choose the OK icon. Choose the Orient View To Model icon.

Adding Extracted Curves to a Sketch Extracting the Edges You want an associative copy of the "front" edges of the "groove" copied into the sketch.

Choose the Add Extracted Curves icon. You get the Extract Objects into Sketch dialog.

The three switches allow you to control the type of curve you will get in the sketch: Original will give you the simplest type of curve possible in the sketch. Spline Segment will give you one spline for every selected curve or edge. Single Spline will give you a single spline for all the selected curves or edges.

Adding Extracted Curves to a Sketch Selecting the Edges Leave the switch set to Original, and leave the Tolerance at the default.

642 Select all five edges that make up the inside of the groove.

OK the dialog.

You now have a string of associated curves in the sketch (three lines and two arcs).

Adding Extracted Curves to a Sketch Creating the Arc If you create the arc between the top ends of the vertical lines in the sketch, when the size of the base block changes, so will the extracted lines, as well as the ends of the arc. Make Layers 10 and 62 Invisible. Choose the Orient View To Sketch icon.

Create an arc. Make sure to select the ends of the vertical lines for the first and second points. It should look approximately like the arc shown below.

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Choose the Arc icon. Make sure the Arc by 3 Points icon Select the locations shown below:

is active.

Cancel arc creation.

Adding Extracted Curves to a Sketch Creating a Point on Curve Constraint For this design, you will not need to constrain the size of the arc, but you want the slope of the left end of the arc to be perpendicular to the left vertical line. This will determine the radius needed for the arc. You can accomplish that by constraining the center of the arc to be on the left vertical line.

Choose the Create Constraints icon. Zoom out and select the center of the arc.

Select the left vertical line (make sure you select the line, and not the sketch).

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Adding Extracted Curves to a Sketch Finishing the Constraint Choose Point on Curve icon. The sketch is now fully constrained, and it meets all the design criteria. Cancel constraint creation. Choose the Finish Sketch icon

to exit the Sketcher Task Environment.

Adding Extracted Curves to a Sketch Extruding the Sketch

Now you will create the web, by extruding the sketch between two faces/planes. Make layers 10 and 61 Selectable. You can see that a datum plane has been created. This is to locate the back face of the web.

Choose the Extruded Body icon. Select any of the sketch curves, and OK the dialog. Choose Trim Between Two Faces/Planes. The direction arrow needs to point toward the solid. If it does not, use Cycle Vector Direction until it does. OK the Vector constructor dialog.

Adding Extracted Curves to a Sketch Selecting the Trim Faces Select the left end face of the part. Turn on Extend Trim Face. OK the dialog.

645 For the second trimming face, select the Datum Plane and OK the dialog. Leave the Offsets and Taper values set to 0. OK the Extruded Body dialog Choose Unite. Cancel the dialog. Make layer 61 Invisible. If you have the capability, Shade the view.

Adding Extracted Curves to a Sketch Testing the Results Now you will edit the width of the block, and see how the part updates.

Choose the Edit Feature Parameters icon

or choose Edit

Feature

Select BLOCK(0) on the Edit Parameters dialog, and OK the dialog. Choose Feature Dialog. Enter 75.0 in the X Length field and OK the dialog. OK the dialogs until the part updates.

Notice that within the sketch, the extracted curves updated and the arc followed. Close the part file.

Parameters.

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Constraining Sketches - Exercises In this lesson, you will work through a number of exercises that will help you practice constraining sketches. In the process, you will also learn some new constraint techniques.

Practice Part #1 - Constraining a U-Shape In this section, you will constrain a sketch of a U-shaped cross-section. The design requirements for this part are: The length and the width are parametrically controlled. The thickness is parametrically controlled and must be the same throughout the part.

Practice Part #1 - Constraining a U-Shape Opening the Part Open part file skt_const_1.prt from the skt subdirectory, and start the Modeling application. Choose the Open icon. Choose the Modeling icon

or choose Application

Modeling.

This part file contains a sketch, which is on layer 21. You will constrain this sketch to satisfy the design requirements.

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Choose the Display WCS icon

or choose WCS

Display to turn the display off.

Activate the one sketch in the part. Double-click on any curve in the sketch.

Practice Part #1 - Constraining a U-Shape Examining the Sketch

Before you start, you should examine the sketch. You can use Show All Constraints and Show/Remove Constraints to examine the types of constraints that currently exist on this sketch. First you will turn off the display of the WCS, so that you can see all the geometry more clearly.

Choose the Show All Constraints icon. Turn off Dynamic Constraint Display. Choose Preferences Sketch. Turn off Dynamic Constraint Display. Now if you are zoomed back, ALL the constraint symbols will still display. OK the Sketch Preferences dialog. Zoom up on the part, and carefully examine the constraint symbols. Look for missing constraints - especially in the upper left and upper right corners of the part.

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Did you notice that there is no Horizontal constraint on the upper left line? And that there is no Coincident constraint at the upper right corner?

Choose the Show All Constraints icon of constraints.

to change the display back to normal display

Practice Part #1 - Constraining a U-Shape Fixing the Location of the Sketch

To make it easier to see the constraint status of the sketch, you will apply a Fixed constraint to fix the location of the sketch in space. Create a Fixed constraint on the upper left corner of the sketch. Choose the Create Constraints icon. Select the point indicated below. (If you select the endpoint correctly, the Fixed constraint will be the only constraint available.) Choose the Fixed icon.

Practice Part #1 - Constraining a U-Shape Constraining the Length and Width The design requirement for the length and width can be met with simple overall dimensional constraints (sketch dimensions).

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Choose the Dimensions icon. Create a Horizontal dimensional constraint for the overall length of the sketch, and a Vertical dimensional constraint for the overall height. Do not worry about specific values yet. Choose the Horizontal icon. Select the two outer vertical lines, in any order.

Move the dimension into place and click MB1. Choose the Vertical icon. Select the upper and lower horizontal lines as shown below.

Move the dimension into place and click MB1.

Your sketch dimensions should look like this.

Cancel dimension creation.

Practice Part #1 - Constraining a U-Shape Preparing to Close a Gap in a String of Curves

650 In order to complete constraining this sketch, the curves must form a continuous string. In some cases, when the ends of the curves are not contiguous, you can use the coincident geometric constraint to close the gap. Zoom in on the upper right corner of the part. You can see that there is a small gap between the ends of two of the lines. When you first examined the part, you also should have noted that there was no Coincident constraint at this location.

Use Analysis Distance to determine the size of the gap. (Make sure you find the distance between the end points of the two lines.) The distance between the two end points is approximately .685 mm; therefore, you need to tell the system to close any gap that is that size or smaller.

Practice Part #1 - Constraining a U-Shape Closing Gaps by Creating Coincident Constraints Automatically By using the Automatic Constraint Creation, you can ensure that there are no gaps in a string of curves.

Choose the Automatic Constraint Creation icon. The Auto Create Constraints dialog is displayed. It shows you all the types of geometric constraints you can have the system automatically create. Choose Clear to remove the current Auto Create settings. Choose Coincident to turn the option on.

The "Distance" value determines which points will be made coincident. Any two points which are within this distance of each other will be considered to be one point.

651 Since the gap you found was about 0.68, you need to use a distance value that is a little larger. Key in 0.700 in the Distance field.

OK the dialog. The requested geometric constraints are automatically created. Notice that the gap between the ends of the two lines has been closed, and the end points are now coincident.

Practice Part #1 - Constraining a U-Shape Constraining the Thickness of the Part Next, you will constrain the thickness. Create a Perpendicular dimension between the two horizontal lines as shown below. Do not key in a specific value yet. Choose the Dimensions icon. Choose the Inferred icon. Select the two horizontal lines.

Position the dimension and click MB1.

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Practice Part #1 - Constraining a U-Shape Dimensioning the Fillets You need to apply a radius dimension to one of the fillets and then relate the other fillet radius to it. Apply a Radius dimension to the inner fillet on the left. (You may need to use Zoom so that you can select this small radius.)

NOTE: You can use Zoom and Pan in the middle of creating a dimension, even while the new dimension is rubber-banding, to help you select the geometry and position the dimension. Remember, you can use MB2 to cancel the graphics operation. Apply another Radius dimension, this time to the outer fillet on the left.

Practice Part #1 - Constraining a U-Shape Making the Radii Equal You do not have to dimension the other two arcs - you can simply specify that they are to be equal to the arcs you have already dimensioned. Create an Equal Radius constraint between the two smaller radii on the inside of the part.

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Choose the Constraint icon. Select the two smaller arcs. (Zoom in if necessary to be sure you get the arcs, not points or lines.)

Choose the Equal Radius icon. Create an Equal Radius geometric constraint between the two larger radii on the outside of the part. Select the two larger arcs.

Choose the Equal Radius icon.

Practice Part #1 - Constraining a U-Shape Applying a Collinear Constraint The two small lines at the top of the part must be collinear. The Collinear geometric constraint allows you to define and constrain lines as extending through the same point and parallel to each other. Even though the small line on the left is not horizontal, it is not necessary to put a horizontal constraint on it. Since the other line is horizontal, the collinear constraint will be enough. With Create Constraints still active, select the two small lines. (Zoom in on your selections, because these lines are small and you need to be sure to select the lines, not their endpoints.)

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Choose the Collinear icon.

Practice Part #1 - Constraining a U-Shape Applying Perpendicular Dimensions There are still a few DOF arrows remaining, and the Status area tells you that you need two more constraints. You have not specified all of the part thicknesses. Create Perpendicular dimensions between the two sets of vertical lines. Choose the Dimensions icon. Choose the Inferred icon. Select the first pair of vertical lines.

Position the dimension with MB1.

Select the second pair of vertical lines.

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Position the dimension.

Now the sketch is fully constrained (see the Status area, and notice that all the DOF arrows have been removed). However, the design intent is not completely satisfied.

Practice Part #1 - Constraining a U-Shape Using Expressions to Make Dimensions Equal Remember this design requirement? The thickness is parametrically controlled and must be the same throughout the part. The first part of this requirement has been satisfied, but the second has not. You must make all the thicknesses equal. You can have one dimension define the thickness and then have the other dimensions refer to it. You could do this using the Dimensions dialog, but you are going to use the simpler method. Cancel the Dimensions dialog. Double-click on the p5 dimension (that constrains the thickness of the left vertical side). A dynamic input box appears on the graphics screen.

Key in p2 in the right (value) field, then press Enter.

656 The sketch is immediately updated. Make p6 (the dimension on the other upright) equal to p2 in the same way. To test your constraints, you can change the value of p2. Change the value of p2 to 7.0. All three thicknesses change together.

Practice Part #1 - Constraining a U-Shape Controlling the Thickness Through the Radius Areas Even though the thickness of the part is the same over most of its length, the thickness through the radius area is still not consistent.

Using the same procedure, change the value of p4 (the larger fillet) to 12.0.

Since you applied an equal radius constraint to the two large arcs, they are both changed. Now the radius of the smaller arc needs to be made equal to the radius of the larger arc, minus the thickness (p2). Change the value of p3 to p4-p2.

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Practice Part #1 - Constraining a U-Shape Finishing Now you have completely satisfied the design intent. To verify this, you can change the values of the relevant dimensions. Another way to control the thickness through the bend areas is to use geometric constraints to make the outer and inner radii concentric. (You would then need to remove one of the two radius dimensional constraints.) Change the value of p2 to 10.000. All the thickness values are updated.

Of course, if you made p2 too large, without also increasing the size of p4, the inner radius would not be a valid value, and you would get incorrect results. You could avoid this problem with the use of conditional expressions, which are covered in the Expressions CAST course. Change the value of p0 (the length) to 110, then change the value of p1 (the height) to 50. The entire sketch is updated to the new dimensions. You can see that all elements of the design requirements have been satisfied. (Remember, you fixed the top left endpoint on the sketch plane.)

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You can experiment with other dimension values if you wish.

Finish

the sketch.

Close the part file.

Practice Part #2 - Constraining an Angled Part The design requirements of this next part are that: You must be able to control the length and height of the part and the angle of the ramp. The thickness must remain uniform throughout the part. The angled ramp must start 1/3 of the way along the length of the part.

Practice Part #2 - Constraining an Angled Part Opening the Part Open part file skt_constr_2.prt from the skt subdirectory.

659 This part file contains a sketch, which is on layer 21. You will constrain this sketch so that it satisfies all the design requirements.

Start the Modeling application.

Practice Part #2 - Constraining an Angled Part Examining the Sketch Before you start, you should examine the sketch. First you will turn off the display of the WCS, so that you can see all the geometry more clearly.

Choose the Display WCS icon

or choose WCS

Display to turn the display off.

Activate the one sketch in the part. Double-click on any curve in the sketch.

You can use Show All Constraints and Show/Remove Constraints to examine the types of constraints that currently exist on this sketch.

Choose the Show All Constraints icon. Be sure that Dynamic Constraint Display is turned off. Choose Preferences Sketch Turn off Dynamic Constraint Display. Now if you are zoomed back, ALL the constraint symbols will still display. The constraint symbols show you that several of the lines are already constrained to be horizontal and vertical, and all the end points have coincident symbols. There are no other constraints.

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Turn off Show All Constraints

to return to the standard constraint display.

Practice Part #2 - Constraining an Angled Part Fixing the Location of the Sketch To make it easier to see the constraint status of the sketch, you will fix the location of the sketch in space.

Make sure the Delay Evaluation icon is off. Create a Fixed constraint on the lower left corner of the sketch. Choose the Create Constraints icon. Select one of the end points at the lower left corner of the part.

Choose the Fixed icon.

The degree-of-freedom arrows on the point are removed.

Practice Part #2 - Constraining an Angled Part Applying Additional Constraints Before you start creating dimensions, you should apply two additional geometric constraints. The line on the far left needs to be constrained to remain vertical. Create a Vertical constraint on the line at the left of the sketch. Select the line.

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If you accidentally select an endpoint, rather than the line itself, choose the Create Constraints icon twice - the selection process will be initialized. Choose the Vertical icon. Now the line will always be vertical.

You must constrain the angled lines in the center to remain parallel. Create a Parallel constraint on the two lines in the center of the sketch. Select both lines.

Choose the Parallel icon.

Now you are ready to create the dimensions to complete the sketch.

Practice Part #2 - Constraining an Angled Part Constraining the Length and Height First you will apply dimensional constraints (sketch dimensions) to control the length and height of the part, and the start and angle of the ramp.

Choose the Show No Constraints icon Choose the Dimensions icon.

to simplify the screen.

662 Constrain the overall length of the sketch, and the overall height. Select the two vertical lines.

NOTE: If you have trouble selecting the small lines, you can decrease the size of the selection ball using Preferences Selection. Place the dimension.

Select the upper and lower horizontal lines as shown below.

Place the dimension.

Practice Part #2 - Constraining an Angled Part Dimensioning the Angle Now you need to control the angle of the ramp. Remember, when creating an angular dimension, you need to select the lines in a counterclockwise direction, toward the end of the line where you want to measure the angle. Create an Angular dimension between the two lines in the center of the sketch.

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Choose the Angular icon on the dialog. Select the lines, toward the right end, as shown here.

Place the dimension.

Practice Part #2 - Constraining an Angled Part Constraining the Length of the Ramp The length of the horizontal line on the left determines the start of the ramp. Create a Horizontal dimension to control the length of the horizontal line on the left. Choose the Inferred icon Select the line.

Place the dimension.

on the dialog.

664 Remember that the design requirement is that this dimension be equal to 1/3 of the overall length. Use the Dimension dialog to change the value of this dimension to be equal to 1/3 of the length of the sketch. Key in p0/3 in the expression value field in the dialog. Press Enter.

Practice Part #2 - Constraining an Angled Part Constraining the Thickness The thickness of the part must be constrained so that it remains uniform throughout the part. Create a Vertical dimension for one end of the sketch. You should still be in the Dimensions dialog. If not, choose the necessary icon. Select the vertical line on the left. (Zoom in if necessary.)

Place the dimension.

665 Remember, if your dimensions start interfering with each other, you can move them using MB1.

Practice Part #2 - Constraining an Angled Part Making the Thicknesses Equal Create a Perpendicular dimensional constraint between the lines that define the ramp, and set its value equal to the vertical thickness dimension. Select the two angled lines in the center.

Place the dimension. Change the expression value to be equal to the vertical dimension, p4, then press Enter.

You also need to constrain the thickness of the part on the right side of the sketch. You could do this in the same way as the others - by creating a dimension. But you can also just specify that the two vertical lines must be the same length. Create an Equal Length constraint for the two vertical ends of the sketch. Choose the Create Constraints icon. Select the two vertical lines. (You may need to zoom in to make sure you get the lines, not their endpoints.)

Choose the Equal Length icon.

666 All the DOF arrows are removed, and the Status area tells you that the sketch is fully constrained. In addition, because you set up the values of the dimensional constraints correctly, you have satisfied all of the design requirements, i.e.: You must be able to control the length and height of the part and the angle of the ramp. The thickness must remain uniform throughout the part. The angled ramp must start 1/3 of the way along the length of the part.

Practice Part #2 - Constraining an Angled Part Testing the Constraints You can change some of the dimensions, to demonstrate that the original design intent has been satisfied. You can delay the evaluation of the sketch until after you have changed all the dimension values.

Choose the Delay Evaluation icon. By double-clicking on the dimensions, change the values: p0=140, p1=30, p2=35, and p4=12. Choose the Evaluate Sketch icon. The sketch is updated, and you can see that all the correct relationships were maintained between the sketch objects.

Remember, this exercise showed only one of the possible ways to meet the design intent there are certainly others. Close the part file.

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Practice Part #3 - Constraining Relative to a Centerline The design requirements of this part are that: Both fillets must have the same radius. The lengths of L1 and L2 are equal. All dimensions must be relative to the centerline of the part. The chamfers must have the same size and angle. The length of the part must be equal to the length of the centerline.

Practice Part #3 - Constraining Relative to a Centerline Opening the Part Open part file skt_constr_3.prt from the skt subdirectory. This part contains a sketch named SKETCH_021, which is on layer 21 (the current work layer). The sketch was created, then existing curves were added to it. The curves were not created in the sketch.

Turn off the WCS Display.

668 Start the Modeling application and activate the sketch. Choose the Modeling icon or choose Application Double-click on any of the sketch curves.

Modeling.

Practice Part #3 - Constraining Relative to a Centerline Creating Constraints First you will create some basic constraints to fix the location of the sketch, constrain the lines to horizontal and vertical, and constrain the fillets to be tangent to the adjacent lines. Before you start, you should check to see what constraints already exist.

Choose the Show All Constraints icon.

so you can see all the created constraints.

Use the Sketch Preferences dialog to turn off Dynamic Constraint Display. There are no constraints except the Coincident constraints at the ends of the curves. This is because these curves were created outside of the sketch, and then later added to the sketch. If the sketch curves had been created in the sketch, rather than added to the sketch, many constraints would already exist. If necessary, turn off Delay Evaluation. Create a Fixed constraint on the point at the lower left corner of the sketch. (This is at the origin of the WCS.) Choose the Create Constraints icon. Select the lower left end point of the part.

Choose the Fixed icon.

669 The DOF arrows on the point are removed.

Practice Part #3 - Constraining Relative to a Centerline Automatically Applying Constraints Because these curves were added to the sketch, instead of being created in the sketch, no constraints exist. One way you can apply geometric constraints is by letting the system automatically create them for you. You will use the Automatic Constraint Creation icon to apply Horizontal, Vertical, and Tangent geometric constraints.

Choose the Automatic Constraint Creation icon. The Auto Create Constraints dialog is displayed. It shows you all the types of geometric constraints you can have the system automatically create.

The settings are the same as what was last used. When you start a new session of Unigraphics NX, Horizontal, Vertical, Parallel, Perpendicular, and Tangent constraint types are selected by default.

Practice Part #3 - Constraining Relative to a Centerline Applying the Constraints At the bottom of the dialog, you see the tolerances that are used to determine whether geometry will be constrained. For example, in this case, if a line is within 3 degrees of horizontal, and the Horizontal option is selected, the line will be constrained to be horizontal.

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Choose Clear, then turn on Horizontal, Vertical, and Tangent. OK the dialog.

Now you can see that there are many constraints in the sketch.

Practice Part #3 - Constraining Relative to a Centerline Constraining the Fillets To satisfy the first design requirement, that the fillets have equal radii, you can apply one radius dimension and an equal radius constraint. Create an Equal Radius constraint for the two fillets. Choose the Create Constraints icon. Select the two fillets. (Use Zoom to make sure you get the arcs and not other geometry, since they are quite small.)

Choose the Equal Radius icon. Create one Radius dimension. Do not add a specific value yet. (Again, use Zoom if necessary to be sure you select the radius.) Choose the Dimension icon. Select one of the fillets.

671 Place the dimension.

Practice Part #3 - Constraining Relative to a Centerline Constraining the Equal Length Lines The second requirement of the design intent is that the two short horizontal lines must have equal lengths. You can apply a constraint to satisfy this requirement. Create an Equal Length geometric constraint for lines L1 and L2. Choose the Create Constraints icon. Select the two lines.

Choose the Equal Length icon.

You also need to apply an equal length constraint to the vertical lines connected to the arcs. Create an Equal Length constraint for the two short vertical lines. Select the two lines. (You will almost certainly need to zoom in on these areas, to make sure you get the lines themselves, rather than endpoints.)

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Choose the Equal Length icon.

Choose the Create Constraints icon constraint creation.

or press Esc (on Windows only) to cancel

Practice Part #3 - Constraining Relative to a Centerline Converting Curves to Reference Curves The lines at the left and the bottom are necessary to constrain your sketch, but you do not want them to be part of any feature you would create from the sketch. They must be converted to reference curves. Convert the lower vertical and horizontal lines to reference curves. Choose the Convert To/From Reference icon. Make sure Reference is chosen, and select the two lines, then OK the dialog.

Practice Part #3 - Constraining Relative to a Centerline Creating the Vertical Dimensions The third requirement of the design intent is that all dimensions are to be related to the centerline of the part, like this:

673 You can apply horizontal and vertical dimensional constraints to satisfy this requirement. Use the Shift-MB2 to access the Pan function to move the part over to the right before you start, to give yourself enough room for the dimensions. Use MB2 to cancel "pan" mode. You may wish to turn off Show All Restraints - to simplify the display. If you do so, from time to time you may want to turn it back on. Create the three Vertical dimensions.

Choose the Dimensions icon. Select the centerline and the lower horizontal line, in any order.

Place the dimension.

Create the other two dimensions in the same way.

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Practice Part #3 - Constraining Relative to a Centerline Creating the Horizontal Dimensional Constraints Create two Horizontal dimensional constraints.

Select the lower left horizontal line.

Place the dimension.

Select the two vertical lines.

Place the dimension.

Most of the DOF arrows have been removed, because the part is almost fully constrained.

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Practice Part #3 - Constraining Relative to a Centerline Dimensioning the Chamfers One of the remaining design requirements is that both chamfers have the same size and angle. First, you will dimension the chamfer on the left. Create a horizontal dimension for the length of the chamfer. Select the angled line.

Move the cursor around. You will see the dimension change from horizontal, to vertical, to parallel, depending on the cursor location. When the dimension is in horizontal mode, and in the correct position, click MB1.

Create an angular dimensional constraint on the chamfer. Select the upper horizontal line, then the angled line, as shown here. (Remember, you must select the lines in a counterclockwise direction.)

Place the dimension.

Dimension the other chamfer in the same way.

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Practice Part #3 - Constraining Relative to a Centerline Making the Chamfers Equal Now you must specify that the two chamfers have the same size and angle. Edit the two dimensions on the second chamfer to be equal to those on the first chamfer (i.e., p8=p6 and p9=p7).

You could also have set the dimensions to these values as you created the dimensions.

Practice Part #3 - Constraining Relative to a Centerline Controlling the Length with the Centerline The final design requirement has not yet been satisfied - that the overall length of the part must be controlled by the length of the centerline. Create a horizontal dimension for the length of the centerline.

677 Now the overall length dimension must be made equal to this dimension. Select p5 (the overall length parameter) and change its value to be equal to p10.

Practice Part #3 - Constraining Relative to a Centerline Checking Your Constraints All DOF arrows have been removed, and the part is fully constrained. Also, you have satisfied all of the design requirements. You can test this by changing some of the dimension values. Change the value for p10, the length of the centerline, to see the effect. Change the values of p6 and p7, the length and angle of the chamfers. You can also change the dimension values by changing the expressions using Tools Expression. Close the part file when you are done.

Practice Part #4 - Constraining Arc Centers The design requirements of this part are that: The inner hole must be concentric with the arc at the top of the part. The overall height and width can be parametrically controlled. The overall width must be three times the diameter of the inner hole.

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Practice Part #4 - Constraining Arc Centers Opening the Part Open part file skt_constr_4.prt from the skt subdirectory.

This part contains a sketch named SKETCH_000 on layer 21. There are no curves in the sketch. The curves are on layer 41 and have been created outside of the sketch. They must first be added to the sketch, and then the constraints can be applied. Turn off the display of the WCS. Start the Modeling application and activate the sketch. Choose the Modeling icon

or choose Application

Modeling.

Choose the Sketch icon or Insert Sketch. Select SKETCH_000 in the sketch name field.

Practice Part #4 - Constraining Arc Centers Adding Curves to the Sketch You are ready to add the curves to the sketch. Fit the view. Choose the Add Existing Curves icon

on the Sketch Operations toolbar.

Choose Select All on the Add Curves selection dialog, then OK the dialog.

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All the curves you selected have been moved from their original layer (41) to the current work layer (21), the layer the sketch is on.

Practice Part #4 - Constraining Arc Centers Checking the Constraints in the Sketch If you choose Create Constraints, the status area tells you that the sketch is under constrained -- it needs 14 constraints. Use the Show All Constraints to see what constraints have been created or inferred. If necessary (to see all the constraints), turn off Dynamic Constraint Display. Choose Show All Constraints. You can see that no constraints have been inferred by the system. When you add geometry to a sketch, the system does not infer horizontal, vertical, tangent, or other constraints that would normally be inferred if you created the geometry in the sketch. Also, remember that if the added geometry is not trimmed correctly, you may have gaps or overlaps between line endpoints when they are added to a sketch. Zoom in on the lower right corner of the geometry.

Notice that the two lines overlap, and that neither line is horizontal nor vertical.

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Practice Part #4 - Constraining Arc Centers Analyzing the Overlap You first need to determine how much overlap there is in the lower left corner of the geometry. Choose Analysis

Distance from the menu bar.

Choose Point Constructor on the Distance Analysis dialog. Select the bottom end of the right vertical line.

Choose Point Constructor again. Select the right end of the horizontal line.

The Information window displays the distance between the two selected end points, and it is also displayed on the graphics screen.

Remember the 3D Distance value. Dismiss the Information window. Cancel the Distance Analysis dialog.

Practice Part #4 - Constraining Arc Centers Automatically Adding Some Geometric Constraints You will now use the Automatic method of adding some of the needed constraints.

681 You need to have the "horizontal" and "vertical" lines constrained to be horizontal or vertical. You also need to correct the overlap and need to add the tangent constraints for the large arc.

Choose the Automatic Constraint Creation icon. Turn on Horizontal, Vertical, Coincident, and Tangent. Remember the gap you need to close (between the ends of the two lines) is 1.99 millimeters plus. So a Distance value of 2.5 will more that adequately close the gap. Enter a Distance value of 2.50. OK the dialog.

The overlap appears to be gone and the lines all appear to be horizontal or vertical.

Practice Part #4 - Constraining Arc Centers Checking the Constraints Again Use the Show/Remove Constraints icon to see what constraints have been added. Choose Show/Remove Constraints. Make sure Show Constraints is set to Explicit. Choose the All in Active Sketch option.

You can see that many constraints have been created. In the list above, you may notice that it is missing one of the two needed tangency constraints. Notice also that there is now a coincident constraint at the lower right corner.

682 Cancel the Show/Remove Constraints dialog.

Practice Part #4 - Constraining Arc Centers Applying a Fixed Constraint to the Sketch One point on the sketch needs to be located. You will use the lower left corner. Add a Fixed Geometric Constraint to the lower left corner of the geometry. Choose the Create Constraints icon. Select the lower end of the left vertical line (or the left end of the horizontal line). Choose Fixed icon.

Practice Part #4 - Constraining Arc Centers Applying a Tangent Constraint If needed, create tangency constraints for any that are missing. With Create Constraints active, select the two curves missing a tangency constraint. Choose the Tangent icon.

Applying a Concentric Constraint One of the design requirements is that the inner hole be concentric with the top radius. You can apply a constraint to satisfy this requirement by creating a Concentric constraint to the arc and circle. You should still be in Create Constraint mode.

683 Select the large arc and the small circle, in either order.

Choose the Concentric icon. The circle moves to the center of the arc, and some of the DOF arrows are removed.

Applying a Concentric Constraint Applying a Vertical Dimension One of the design requirements is that the overall height and width be parametrically controlled. The diameter of the large arc will control the width and a vertical dimension will control the overall height of the sketch. Create a Vertical dimension from the horizontal line to the top of the large arc.

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Choose the Dimension icon. Choose the Vertical icon. Select the arc and the horizontal line.

Move the dimension into position and click MB1.

Applying a Concentric Constraint Applying a Dimension to Control the Width Now you will apply constraints to control the width. Create a Radius dimensional constraint for the arc. Choose the Inferred icon. Select the arc. Move the dimension into position and click MB1.

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Notice that a number of the DOF arrows were removed.

Applying a Concentric Constraint Applying a Dimension to Control the Diameter of the Circle Create a Diameter dimension for the circle. Select the circle. Move the dimension into position and click MB1.

The final DOF is removed, and the Status area informs you that the sketch is fully constrained. However, the design requirements are not completely satisfied.

Applying a Concentric Constraint Relating the Large Arc to the Small Hole One more design requirement must be met - the width of the part must be three times the diameter of the inner hole. Change the value of the arc radius to be equal to 3 times the circle diameter, divided by 2.

686 In the Dimensions dialog, select p1 (the radius of the arc). Under Current Expression, change the value to (3*p2)/2, then press Enter.

Applying a Concentric Constraint Testing the Constraint Try an experiment to see how changing the diameter of the small hole affects the overall part. Change the value of p2 to 15.20 and press Enter. The height is unaffected, since it is controlled by the vertical dimension only. However, both the size of the smaller circle and the overall width changed, since the width is related to the diameter. Close the part file.

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Practice Part #5 - Constraining the Perimeter of a Sketch The design requirement for this part is that the length of the perimeter of the part must remain constant, regardless of the other changes to the part. This can be accomplished using the Perimeter constraint. Open part file skt_constr_5.prt from the skt subdirectory.

This part is similar to the first practice part you worked on. However, it has already been partially constrained. Start the Modeling application and activate the sketch. Choose the Modeling icon or choose Application Double-click on any of the sketch curves.

Modeling.

Notice that the Status area tells you that the sketch needs 1 constraint.

Practice Part #5 - Constraining the Perimeter of a Sketch Adding the Perimeter Constraint You could fully constrain the part by adding a horizontal dimension for the overall length. However, this time you will add a perimeter constraint instead. This constraint lets you control the entire length of the objects you select. You want to control the combined length of all the outer curves in the sketch.

Choose the Dimensions icon.

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Choose the Perimeter icon. The Cue line tells you to select the lines and arcs to create the perimeter dimension. Select all outer the lines and arcs in the sketch.

OK the dialog. The perimeter dimension is created, and the sketch is fully constrained. The perimeter dimension is displayed at the top of the list in the list box.

Unlike other dimensional constraints, perimeter constraints are not displayed in the graphics area. You do not have to select an entire closed perimeter - any number of contiguous lines and arcs can be selected.

Practice Part #5 - Constraining the Perimeter of a Sketch Changing the Perimeter Dimension You can use the perimeter dimension to change the shape of the part in two ways: Change the value of the perimeter dimension itself, or Change the value of another dimension in the perimeter string. Change the value of the Perimeter_p5 dimension to 170.

689 The length of the part changes, but all the other dimensions remain the same.

Now you will change the size of one of the elements that make up the perimeter, and the sketch will be adjusted to maintain the same perimeter length. Notice that the p0 dimension controls the entire thickness of the part (the two short horizontal lines have an Equal Length constraint). Change p0 to 5.0. The shape of the part changes, but the overall length of the perimeter is still 170.

Experiment with changing other dimensional constraint values to see the effects. Close the part file when you are finished.

Practice Part #6 - Constraining a Hex Shape The design requirements of this part are that: It must be constrained so that it is a true hexagon (i.e., all the internal angles are 120 degrees). Its size is determined by the size of the inscribed arc, so that the hexagon can be modified by changing a single dimensional constraint.

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Practice Part #6 - Constraining a Hex Shape Opening the Part Open part file skt_constr_6.prt from the skt subdirectory. This part contains a sketch named SKT100 on layer 100. As you can see, the lines need to be constrained in relationship to the circle.

Turn off the display of the WCS. Start the Modeling application, and activate the sketch. Choose the Modeling icon or choose Application Double-click on any curve in the sketch.

Modeling

Practice Part #6 - Constraining a Hex Shape Examining the Part First you want to see what constraints, if any, exist for the sketch. Check to see what constraints already exist in this sketch. Choose the Show All Constraints icon. Turn off Dynamic Constraint Display.

You can see that two horizontal constraints were applied when the sketch was created. In addition, a Fixed constraint was applied to the center of the circle.

Practice Part #6 - Constraining a Hex Shape Adding Tangent Geometric Constraints

691 In order to satisfy the design requirements, you must apply some more constraints. Since the size of the inscribed arc will determine the size of the hex, you must specify that each of the lines must be tangent to the circle. Create Tangent geometric constraints between the circle and each of the six lines. Choose the Create Constraints icon. Select the circle, then one of the lines. Choose the Tangent icon. Repeat the last 2 steps for each of the other lines, so that all lines are tangent to the circle.

The part should now look like this:

Practice Part #6 - Constraining a Hex Shape Adding Parallel Geometric Constraints Next you will create parallel constraints between the pairs of angled lines. This will minimize the number of dimensions you will have to add. Create Parallel geometric constraints for each of the two pairs of angled lines.

692 With Create Constraints active, select the first two lines (avoiding their control points). Choose the Parallel icon. Repeat these 2 steps for the other pair of lines.

Practice Part #6 - Constraining a Hex Shape Adding Dimensions Finally, you will apply some dimensions to complete the part and satisfy all the design requirements. Apply Angular dimensions as shown on two adjacent sides of the hexagon. (Make sure both values are exactly 60 degrees - change them if necessary.)

Choose the Dimensions icon. Remember, when selecting lines for an angular dimension, it is important that you select in a counterclockwise direction, toward the end of the line where you want the angle to be measured from. Select the first line on the lower half, as shown below.

Select the second line on its right half, as shown below.

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Position the dimension, then change its value to 60.

Remember, you can zoom and pan the graphics area while the dimension is rubberbanding. This can help you position the dimension exactly where you want it. Select the other two lines as shown below.

As before, position the dimension, then change its value to 60.

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Practice Part #6 - Constraining a Hex Shape Dimensioning the Circle Even though you have applied all these constraints, no DOF arrows have been removed. You will apply a diameter constraint for the circle - this one dimension will control the size of the hex. Create a Diameter dimensional constraint for the circle. Select the circle. Position the dimension and click MB1.

Notice that all the DOF arrows are removed, and the sketch is completely constrained. Now you can modify the size of the entire hexagon by changing the diameter of the circle. Change the value of the diameter to 50, then press Enter. The dimension is updated and the sketch is resized. If you wish, try other diameter values. Close the part file.

Constraining a Sketch to the Edges of a Body You can also constrain sketch objects relative to geometry on a body. To see how this works you can create a rib on top of a solid.

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The design requirements of this sketch are that the sketch must be controlled by dimensions from edges of the solid. A change to the body must change the sketch and its associated feature.

Constraining a Sketch to the Edges of a Body Opening the Part Open part file skt_constr_7.prt from the skt subdirectory. Start the Modeling application. You may want to turn off the display of the WCS. This part file contains a simple block. To create the rib on the top face, you will create a sketch on top of the block and constrain it relative to the edges of the block. Then you will extrude the sketch, to define a raised rib on the top face.

Constraining a Sketch to the Edges of a Body Creating a Sketch on the Face of a Body The model is on layer 1, and the work layer has been set to layer 51, since it is a good idea to put your sketch on a different layer than the solid body.

Choose the Sketch icon

or choose Insert

Sketch.

Create a sketch named TOP_RIM, using the top face of the body as the sketch plane, and the front face of the part for the horizontal reference.

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Use the front face of the body as the horizontal reference.

Change the Sketch Name to TOP_RIM. (Note: the sketch name is not case sensitive.)

Select the top face of the body. Select the front face. Make sure the orientation is that shown below, and choose the OK icon.

Fit the geometry to the view.

Remember, if Fit does not leave enough room for you to work around the part, you can change the Fit Percentage (on the Visualization Preferences dialog, the Screen tab), then do a

697 Fit again. You can also use the Zoom In/Out option - you will need some room for the dimensions you are going to create.

Constraining a Sketch to the Edges of a Body Creating the Sketch Geometry Now you are ready to create the sketch geometry. The rim of the model needs to be inside the edges of the top face. Create a rectangle inside the face as shown below. The exact size is NOT important.

Choose the Rectangle icon. The Point Constructor dialog is displayed. Indicate (using MB1) two diagonal corners anywhere within the top face of the body, then Cancel the dialog.

Constraining a Sketch to the Edges of a Body Constraining the Sketch to the Edges of the Body All the lines in the rectangle must be the same distance from the edges of the top face of the solid body. Create a dimension between the right edge of the body and the vertical line on the right of the sketch (your dimension value will be different).

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Choose the Dimension icon. Select the right edge of the model (#1 below), then the right vertical sketch line (#2 below). (You can select the sketch geometry and model geometry in any order.) Place the dimension (#3 below).

Constraining a Sketch to the Edges of a Body Creating the Other Dimensions Create three more Perpendicular dimensions. Make each relate the distance between an edge and the closest sketch line.

All DOF arrows have been removed, and the Status area tells you that the sketch is fully constrained. However, the dimensions need to be adjusted so that the sketch is located an equal distance from all edges. The Dimensions dialog should still be displayed.

Constraining a Sketch to the Edges of a Body Delaying Evaluation of the Sketch Since you have several edits to make, you will delay the evaluation of the sketch until you request it.

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Choose the Delay Evaluation icon

to turn it on.

Constraining a Sketch to the Edges of a Body Editing a Dimension Change the value of p3 to 6.0. Select the p3 expression, either in the list box in the Dimensions dialog or in the graphics area. In the right field of the Current Expression area, change the value to 6.0 and press Enter.

The value of p3 in the list box is changed.

Constraining a Sketch to the Edges of a Body Editing the Remaining Dimensions and Evaluating the Sketch Edit the remaining dimensions to all be equal to p3. In the same way as you changed the first dimension, change the value of p4, p5, and p6 to be equal to p3.

The list box in the Dimension dialog should now look like this:

Choose Evaluate Sketch icon

to update the sketch.

It is not actually necessary to choose Evaluate Sketch - the sketch will be automatically updated when you exit from the Dimensions dialog.

700 The distance between the edges of the solid body and the sketch lines is now equal all the way around.

Choose the Finish Sketch icon

to exit the Sketcher Task Environment.

Constraining a Sketch to the Edges of a Body Extruding the Sketch Now, you are ready to extrude the sketch to create a rib on the top face of the model. As before, these steps are brief. All features are explained in detail in the Feature Modeling CAST Online course.

Choose the Extruded Body icon

or choose Insert

Form Feature

Extrude.

Select and accept the sketch, then OK the dialog. Choose Direction_Distance. Accept the default direction. You will make the rim 6 millimeters high, with the widest thickness 3.2 millimeters, and a three degree taper. You want the 3.2 millimeters to be inward, so the Second Offset value may need to be -3.2. Key in the following values:

701 End Distance = 6.0 Second Offset = 3.2 (if the dashed arrow is pointing inward. If not, use -3.2) Taper Angle = 3 OK the dialog. Because you want the rim to be part of the existing body, choose Unite. The sketch is extruded into a feature and united with the existing solid body.

Cancel the dialog.

Constraining a Sketch to the Edges of a Body Examining the Results Use the Shaded icon

to look at the part.

Change to Gray Thin Hidden Edges.

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Constraining a Sketch to the Edges of a Body Editing Dimensions and Updating the Model One of the design requirements was that the sketch must be controlled by a dimensional constraint. You can now verify that this requirement has been met by making the distance between the edges of the block and the rim larger. Change the distance from the edges of the body to the sketch to be 19.0 and update the model. (Turn Delay Evaluation off off so that the sketch will be updated as soon as you change the dimension value.) Double-click on any of the sketch curves to activate the sketch. Choose the Orient View To Model icon. Choose the Delay Evaluation icon option to turn it off. Double-click on the p3 dimension (the first one you created). Change the value of p3 to 19.0, then press Enter.

The sketch is updated. You can see that you changed only one dimensional constraint, but since all other dimensions were set to be equal to the name of the edited dimension, they all changed. The model has not been updated yet.

Update the model.

Choose the Finish Sketch icon

to exit the Sketcher Task Environment.

Constraining a Sketch to the Edges of a Body Editing the Feature Parameters and Updating the Sketch

703 The other design requirement was that a change to the body will change the sketch and its associated feature. To verify that this requirement has been met, you need to edit the block feature parameters. Change the length of the block to 380.0, the width to 150.0, and the height to 4.5. Choose the Edit Feature Parameters icon or choose Edit Parameters. Select the BLOCK(0) feature in the list box, then OK the dialog. Choose Feature Dialog. Change the block parameters to the following values: X Length = 380 Y Length = 150.0 Z Length = 4.5. OK all three dialogs (until the part updates).

Feature

Fit the view. The associativity between the block, top face, sketch, and extruded feature results in the entire model updating.

Try changing other values if you want more practice. Close all part files when finished.

Constraining a Sketch to the Edges of a Body Editing the Feature Parameters and Updating the Sketch

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The other design requirement was that a change to the body will change the sketch and its associated feature. To verify that this requirement has been met, you need to edit the block feature parameters. Change the length of the block to 380.0, the width to 150.0, and the height to 4.5. Choose the Edit Feature Parameters icon or choose Edit Parameters. Select the BLOCK(0) feature in the list box, then OK the dialog. Choose Feature Dialog. Change the block parameters to the following values: X Length = 380 Y Length = 150.0 Z Length = 4.5. OK all three dialogs (until the part updates).

Feature

Fit the view. The associativity between the block, top face, sketch, and extruded feature results in the entire model updating.

Try changing other values if you want more practice. Close all part files when finished.

Dragging Geometry and Dimensions You can drag a vertices and sketch curves. There is no dialog. You simply select what you want to drag, and drag them about the screen using MB1. Dimension values are dragged by using the Dimensions dialog.

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When you drag one or more objects in a sketch, you are modifying constraints that can move. If a sketch is fully constrained, only dimensions can be dragged, since the constraints have no freedom to move. Dragging can give you an easy way to see what is constrained and what is not, since only under constrained geometry moves (unless you are dragging a dimension). If you select any objects that are already constrained, they are simply ignored - they will not move. It is also a handy way to move geometry to a rough desired location prior to positioning it exactly.

Dragging Geometry and Dimensions Opening the Part Open part file skt_drag_1.prt from the skt subdirectory. The part file contains a sketch, which contains four curves that form the shape of a curved slot.

In this activity, you will examine the constraints that exist, and then use the drag capability to visualize how the sketch is still free to change. Start the Modeling application. Choose the Modeling icon

or choose Application

Activate the sketch. Double click on any curve in the sketch.

Modeling.

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Dragging Geometry and Dimensions Examining the Existing Constraints First you will see how this sketch is already constrained. You can see that there is one dimension, which is applied to the radius of one of the smaller arcs.

To examine the constraints, you need to see them all.

Choose the Show All Constraints icon. Turn off Dynamic Constraint Display (Preferences

Sketch).

You can see there is a Fixed constraint applied to the center of the small arc on the left. You can also see that all the arcs are tangent to each other, and the small arcs have the same radius.

Dragging Geometry and Dimensions Examining the Degrees of Freedom Choose the Create Constraints icon

just to display the DOF arrows.

The degree-of-freedom (DOF) arrows show the sketch points that are not constrained. As you can see, that includes all the sketch points other than the center of the small arc on the left.

707 Cancel Constraint Creation.

Dragging Sketch Geometry Now you will use the drag capability to change the sketch geometry and visually display its constraint condition.

Dragging Sketch Geometry Selecting the Geometry First you must select the geometry that you want to drag. You can select geometry individually or by clicking and dragging a rectangle around the desired geometry.

Choose the Show No Constraints icon

to simplify the screen display.

Select the center of the small arc on the right.

Dragging Sketch Geometry Dragging the Selected Geometry In order to drag the selected geometry, the cursor must be over the selected geometry, and be in the "drag" mode.

With the cursor over the selected objects (in drag mode) hold down MB1 and drag the selected point into various shapes.

708 As you move the cursor, the sketch changes dynamically, maintaining the tangent, equal radius, and end radius constraints you have applied.

Release your cursor when you are done moving the shape around.

Dragging Sketch Geometry Finishing the Dragging

The system updates the sketch based on the last position of your cursor, when you released MB1.

Use Undo

to return to the original shape.

You could also use: Ctrl-Z, or Undo from the MB3 pop-up menu, or Edit Undo List Sketch Drag. Practice dragging one more time, this time selecting the large arc. Again, use Undo to return to the original shape.

Dragging Dimension Values You can also "drag" dimension values.

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Choose the Dimensions icon. Select the radius dimension on the screen or on the dimensions dialog.

The current value of the selected dimension is displayed in the dialog, and the scroll bar is activated.

Dragging Dimension Values Dragging the Dimension Value Use MB1 to move the scroll back and forth. The sketch changes as you move your cursor, with the sketch radius becoming smaller or larger, and the radius changing accordingly. Release MB1 when you are finished. When you release MB1, the sketch is changed and updated. Notice that both the small arcs change, since you have an Equal Radius constraint on them. Use Undo to return the sketch to the prior state. Close all part files.

Animating a Dimension You can use the Animate option to dynamically view the effect of changing a single dimension over a range of values.

710 Open part file skt_animate_1.prt from the skt subdirectory.

You will recognize this part from a previous lesson. You will use the Animate function to dynamically alter one of its dimension's values. Start the Modeling application. Activate the sketch.

Animating a Dimension Examining the Part The sketch's dimensional constraints are displayed. You will animate the p4 dimension.

It may be necessary (in order to see all the constraints) to turn on Show All Constraints, and turn off Dynamic Constraint Display. This sketch is constrained the same as the sketch you worked on earlier in this course. You will remember that included making the two short horizontal lines equal length.

You will animate the length of line L3 (the short horizontal line on the left) and see the effect.

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Choose the Show No Constraints icon

to simplify the display.

Animating a Dimension Animating the Dimensional Constraint Choose the Animate Dimension icon. The Animate dialog is displayed, showing a list of the expressions in the part. Select the p4 dimension, either from the list box in the dialog, or in the graphics area.

Notice in the dialog that the system has assigned a lower and upper limit for the animation.

You will change the limits so that the range is greater, and you will also change the number of steps in the cycle. Set the values in the dialog as follows: Lower Limit = 26.0 Upper Limit = 42.0 Steps/Cycle = 15. Apply the changes. The sketch changes dynamically, based on the lower and upper limits, and the number of steps, specified in the Animate dialog. Notice that all the relationships between dimensions and geometric constraints are maintained as the sketch is animated, i.e., since the two lower horizontal lines are set to "Equal Length", they both change during the animation. The overall length (p11) changes also, since it is related to p4. When you are ready, OK the Question dialog to stop the animation.

712 Notice that the dimension is still set to its original value. This option does not actually make any changes to the dimensional constraint - it just lets you see what effect changing it would have.

Animating with Dimensions Displayed You can also display the dimensions while you animate the sketch. Turn on Display Dimensions.

Choose Apply again. This time, as the sketch changes, the dimensions continue to be displayed, at their original values, except for the dimension you are animating. OK the Question dialog to stop the animation. If you wish, choose other dimensional constraints and animate them. When you are finished Cancel the Animate dialog and , close all part files.

Finding an Alternate Solution Sometimes there are more than one solution to a given set of constraints. This can occur with tangent arcs/circles and dimensional constraints. As for dimensional constraints, consider the case below:

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The dimensional constraint merely keeps the two lines 10.0 millimeters apart. It does not know which line should be above the other. There are thus two solutions to the dimension. As for tangent circles, consider:

The circle has been constrained to be tangent to the line. But it does not control whether the circle is above or below the line. There are therefore two solutions here also. Alternate Solution allows you to ask the system to give you the other solution.

Finding an Alternate Solution for a Dimension Open part file skt_altsol_1.prt from the skt subdirectory. Start the Modeling application, and activate the sketch. Choose the Modeling icon or choose Application Double-click on any curve in the sketch.

Modeling

The sketch is fully constrained. You will use Alternate Solution to find the other solution to the 10.0 millimeter dimensional constraint.

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Finding an Alternate Solution for a Dimension Examining the Part First you want to see what constraints exist for the sketch. Check to see what geometric constraints already exist in this sketch. Choose the Show All Constraints icon. Turn off Dynamic Constraint Display (using the Sketch Preferences dialog).

You can see that outside of the horizontal and vertical constraints and the fixed constraint, the two horizontal lines on either side of the "tab" are collinear and equal length. This will keep the "tab" centered on the part.

Choose the Show No Constraints icon

to simplify the display.

Finding an Alternate Solution for a Dimension Finding the Alternate Solution You have decided that the "tab" should be a "slot".

Choose the Alternate Solution icon. The Cue area prompts you to select a dimension or circle/arc. Select the 10.0 millimeter constraint (p3). The sketch immediately changes to the alternate solution for the selected dimensional constraint. You now have the desired "slot".

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Close the part file.

Finding an Alternate Solution for an Arc

Open part file skt_altsol_2.prt from the skt subdirectory. Start the Modeling application and activate the sketch. Choose the Modeling icon or choose Application Double-click on any curve in the sketch.

Modeling

The sketch is not yet fully constrained. The circle is not located. You want it to be tangent to the two angled lines, inside both of them. That will serve to locate the circle.

Finding an Alternate Solution for an Arc Creating the First Tangent Constraint First you will need to create the two tangency constraints to locate the circle.

716 Create a Tangent geometric constraint for the circle and the angled line on the right. Choose the Create Constraints icon. Select the circle and the angled line on the far right (near the locations indicated).

Choose the Tangent icon.

Finding an Alternate Solution for an Arc Creating the Second Tangent Constraint Create a Tangent geometric constraint for the circle and the angled line on the top. Select the circle and the angled line on the top (near the locations indicated).

Choose the Tangent icon.

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The circle is now tangent to both angled lines, but it is not at the location you desired - it is not inside the two lines.

Finding an Alternate Solution for an Arc Finding the Alternate Solutions You need the alternate solutions for both circle/line pairs.

Choose the Alternate Solution icon. The Cue area prompts you to select a dimension or circle/arc. Select the circle and then the angled line on the right. The alternate solution is displayed.

Now select the circle and the angled line on the top.

You now have the desired configuration. Cancel the dialogs. Close the part file.

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Working with Pre-V13.0 Sketches The procedure for creating and editing sketches, as well as the sketch solver, was significantly changed beginning with Version 13.0 of Unigraphics. You cannot edit these older sketches with the new Sketcher. When you edit them, you are presented with the old Sketch Tools and Edit a Sketch dialogs.

If you do not have any sketches that were created prior to V13.0, you can skip this lesson.

Editing Pre-V13.0 Sketches First you will open a part file that contains sketches that were created prior to V13.0. Open part file skt_v12sketch_1.prt from the skt subdirectory. This part file contains five sketches that were created prior to Version 13.0 of Unigraphics.

Start the Modeling application. You will look at one of the pre-V13.0 sketches in this part.

719 Display the Edit Pre-V13 Sketch icon on the Form Feature toolbar. Choose the Edit Pre-V13 Sketch icon.

.

The Edit a Sketch dialog is displayed. The listed sketches are only those created prior to V13.

Select SKT000 in the list box.

The sketch that you selected is highlighted in the graphics area.

Select each of the other sketch names in the dialog to see where they are located in the model. leave the part file open.

Renaming a Pre-V13.0 Sketch You can rename a sketch created in V13.0 or later using the Model Navigator. You can also move a new sketch to another face or plane using the Reattach icon.

720 When you select a sketch name, the Rename and Attach to Face/Plane options become active.

Rename SKT000 to SKETCH0. Make sure SKT000 is selected. Choose Rename. Key in sketch0 for the new sketch name, then OK the dialog.

The name of the sketch is changed.

Activating a Sketch Now you will activate one of the sketches. In the dialog, click on SKT002. The sketch is highlighted in the view.

OK the dialog (or double-click on the sketch name to activate it).

721 The sketch view is displayed. (Prior to V13.0, each sketch had its own view, which was the same name as the sketch.)

Other features do not display in the view because they were masked. That is, the view was edited using the Visible in View dialog.

The Pre-V13.0 Sketch Tools Dialog The pre-V13.0 Sketch Tools dialog is displayed. You can only edit pre-V13.0 sketches using this dialog.

722 Choose Application

Modeling to exit the sketcher.

Notice that, although you exited the sketcher, the sketch view is still displayed. If you need more information about creating and editing sketch curves, constraining, etc. for pre-V13.0 sketches, see your V12.0 or earlier Modeling User Manual (technical documentation). Close all part files.

-ExpressionsExpressions This tutorial was developed to familiarize you with expressions and their usage within Unigraphics NX. It also includes the use of spreadsheet to edit expressions and create part families. Audience This course is designed for Unigraphics NX users who are familiar with Unigraphics NX modeling terms and techniques. You will also need to be familiar with Xess or Excel spreadsheets, which accompany Unigraphics NX, and you must understand basic spreadsheet terms. If you are not experienced in Unigraphics NX modeling, you should go through the Feature Modeling Fundamentals and Feature Modeling - Additional Topics courses in the CAST Online library. Users unfamiliar with Windows terms and functionality can refer to the Unigraphics NX Essentials course in the CAST Online library. Course Content This course contains the following lessons: Overview of Expressions — Defines what an expression is and explains its application,

discussion of the various types of expressions such as arithmetic, conditional and geometric, and the use of boolean operators and built in functions.

723 Creating Expressions — Creating features and the various methods of editing these

features. Using Expressions — Importing and exporting your expressions, filtering, deleting and

renaming your expression, adding comments to your expressions and using the calculator function. Using Spreadsheet — Adding and editing your expressions through the spreadsheet,

creating a family of parts using the spreadsheet, and goal seek and analysis interpretation. Using the Visual Editor — Working with sketches and drawings in the Visual Editor

environment. Expressions Projects — Small projects for you to complete on your own.

Part Files A number of part files have been supplied with this course. Before you start, make sure you know what directory these part files are in. If you do not know, see your system administrator. The names of all the master part files associated with this class start with exp (for "Expressions"). You will not be asked to save your parts as you work through this course. You will not have Write access to the CAST Online part file directory. If you wish to save your work files, you must save them as your personal part files in a directory where you have Write access.

Overview of Expressions The objectives for this lesson are: to introduce you to fundamental expressions concepts to understand expression interdependence to introduce you to arithmetic, conditional and geometric expressions to learn how to use variable names to learn how to use relational and boolean operators in expressions to understand operator precedence and built-in functions as they relate to expressions

What Are Expressions?

724 Expressions are mathematical or conditional equations used to control the parameters of a model. Expressions are used to control feature parameters and dimensional constraints within a part file. All expressions have a value - either a real number or an integer. The value of an expression is obtained by evaluating the right side of the expression. This value is assigned to the variable name, which is on the left side of the expression.

Expression names must be unique characters. No expression can have more than one name. Expression names can be used as variables in other expressions.

Introducing Expressions Choose File Directory.

Options

Load Options and make sure the Load Method is set to From

Open part file exp_part1.prt from the exp subdirectory. The model has the constraining sketch dimensions displayed Each dimension in this sketch is an expression. The sketch is parameterized so that all other dimensions on the sketch are related back to the expression width.

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Choose the Modeling icon Modeling Choose Tools

from the Application toolbar or choose Application

Expression.

The Expressions dialog appears. This dialog gives you a textual listing of all the expressions in the model. You can use this dialog to create and/or edit expressions.

You can also edit expressions using Edit

Feature or the Sketch Tools dialog.

Introducing Expressions The Edit Expressions Dialog

Listing Methods

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List of Expressions

Expressions editor and calculator field

Expression Options

Introducing Expressions Expression Interdependence As you examine the Edit Expressions dialog, notice the following: All the expressions used in the open part are displayed in the list as expressions. All dimensions in the sketch are referencing the variable Width. Width=76.00 p1=Width/3 p2=Width*(3/2) p3=Width/2 p4=Width/6 p5=Width/6 Notice also that the value of Width is currently equal to 76. What would happen to the model if the value was changed? Choose Width=76 from the list of expressions.

Change the value of Width to 50.

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Press Enter to accept the new value. You should now see Width=50 in the list of expressions. Notice the model has not yet been updated.

Apply the change. You could also have used OK to update the part. The OK option will dismiss the Expressions dialog after the part is updated. OK any message dialog you get. When the model is updated, all expressions that use the variable Width are reevaluated. Play around with changing the value for width, see how it affects the value of the other expressions and the overall shape of the part. Close all parts when you are done.

Why Expressions? Expressions are powerful tools that make parametric design possible in Unigraphics NX. With expressions, you can easily apply major edits to a model. By changing the expressions that control a specific parameter, you can resize or reposition features of a solid body. You can also use expressions of a particular part to create variations of that part. By changing expression values, a part can easily be changed into a new part that has similar topology.

Arithmetic Expressions Expressions can use arithmetic operators to help define the left side of the equation. Some arithmetic expressions are listed below:

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Below is a list of the arithmetic operators: Arithmetic Operators + Addition

Example p2 = p5 + p3

- Subtraction and Negative Sign p2 = p5 - p3 * Multiplication

p2 = p5 * p3

/ Division

p2 = p5 / p3

% Modulus

p2 =p5 % p3

^ Exponential

p2 = p5^2

= Assignment

p2 = p5

Conditional Expressions Expressions can also be used to define a variable based on specific conditions. This is done by using the IF ELSE statement.

Every feature parameter and every dimensional constraint within a sketch or model appears as an explicit variable in the expression system. You may manipulate any of the variables in an algebraic statement. Conditional expressions are covered in more detail later in this course.

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Geometric Expressions Expressions can reference geometric properties such as constraints for defining feature parameters. There are three types of geometric expressions: distance - based on the minimum distance between two objects, a point and an object or two points. length - this is based on the length or a curve or an edge. angle - based on the angle between two lines, planar faces, linear edges, datums or a combination of these objects.

Geometric expressions are covered in more detail later in this course.

Variable Names Variable names are alphanumeric strings of text that begin with a letter. An underscore "_" may also be used within a variable name. Variable names are limited to 32 characters in length. Also, expressions are case sensitive. For example, the variable name "X1" is different than "x1". All expression names (left side) are variables and must follow all of the conventions for variable names. Variables used on the right side must be previously defined on the left side of an earlier expression. For example in the expression for "Length", the reference Width must be previously defined. Width=40 Length=2*Width The expression system in Unigraphics NX includes: Operators Built-in math functions Constants

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Relational and Boolean Operators The following is an example of an expression that uses relational (>=,

Greater Than

<

Less Than

>=

Greater Than or Equal

< >= 10, the value for Wdth must be 5. Expressions can also use Boolean operations such as AND or OR. Consider the following:

Here, the Expression for Wdth is defined depending on the following statement: If Lgth is greater than 0 AND less than 10, the value for Wdth is 3. Otherwise the value of Wdth is 5.

Conditional Expressions Using Conditional Expressions Create some conditional statements that will control the position of a slot on an adjustment wheel. Open part file exp_adjst_wheel.prt from the exp subdirectory. The four holes were created by an instance array, and the slot was created by creating a sketch and subtracting it from the flat cylinder.

747

By using conditional expressions you will move the slot as the number of holes in the instance array increases or decreases. Start the Modeling application. Choose the Modeling icon Application Modeling Choose Tools

from the Application toolbar or choose

Expression.

Create the following expressions: Holes=4 SlotEndAngle=195 SlotStartAngle=SlotEndAngle-75

The new expressions are added to the list as you create them. Next, edit some of the existing expressions to use the expressions you just created: (Watch the case!) Current: Change to: p5=120 p5=SlotStartAngle p7=195

p7=SlotEndAngle

p30=4

p30=Holes

The next step is to create the conditional expression that will control the end angle of the slot. Choose SlotEndAngle=195 from the list of expressions, then enter the following conditional statement: SlotEndAngle=if(Holes==5)(150)elseif(Holes==4)(195)else(45)

You can widen the dialog as you key in a long expression like this. When you are using multiple if-else statements, make sure you put a between the else and the if. This statement says that, if there are 4 holes, the end angle for the slot is 195, but if there are 5 holes, the value will be 150. If neither condition is met, the value for the end angle will be set to 45.

748 Test this out by choosing Holes=4 from the list, then change its value to 5. Choose Apply to update the model. Notice that the array now has 5 holes and the slot was repositioned to accommodate the added hole.

Change the value of Holes back to 4 and Apply the change again. This time add another condition to the conditional expression that will allow for 6 holes. Choose the SlotEndAngle expression from the list. Enter the following for the new conditional statement:

SlotEndAngle=if(Holes==6)(105)elseif(Holes==5)(150)elseif(Holes==4)(195)els

You may want to resize the Expressions dialog to see the entire expression string. The new expression is added to the list. Choose Holes=4 from the list and enter 6 for its new value, then choose Apply. Notice that the array is now updated to 6 holes and the slot is again repositioned.

If you had any problems with this activity and would like to see the completed wheel you can open part exp_adjst_wheel_fin.prt. Close all open part files when you are done.

749

Using Geometric Expressions Expressions can be used to define a variable based on abstract geometric properties, such as a minimum distance, or a physical parameter which normal feature parameters do not support, such as arc length. This kind of expression is defined as Geometric Expressions. In this section you will create a geometric expression that will be used to control the size and location of specific holes. Open part file exp_holder.prt from the exp subdirectory. Start the Modeling application. Choose the Modeling icon Application Modeling

from the Application toolbar or choose

Using geometric expressions, you will create mounting holes (2 in each flange). The size and location of these mounting holes will need to be controlled by the length of the flat area on the top of the flange.

Using Geometric Expressions Suppressing Features In order to do this, the flange length (A) must be captured. To find the value of flange length (A), you will need to suppress the corner blend in order to use the edge of the flange.

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Choose the Suppress Feature icon

or choose Edit

Feature

Suppress.

The Suppress Feature dialog is displayed. Choose BLEND(10) from the list, then OK to suppress the feature.

1) length of the flange without the corner blend

You now have an edge whose length you can capture.

Using Geometric Expressions Capturing Expressions Use Tools

Expression to display the Expressions dialog.

Choose the Geometric Expressions icon The Geometric Expression dialog is displayed.

Choose the Length icon. Select the flange length, then OK.

on the dialog.

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Scroll down in the listing area so that you can see the new geometric expression you just created.

OK the Expressions dialog. Choose the Unsuppress Feature icon

or choose Edit

Feature

Unsuppress.

The Unsuppress Feature dialog is displayed. Choose BLEND(10) from the list, then OK to unsuppress the feature.

Using Geometric Expressions Reordering Features Open the Model navigator.

Choose the Model Navigator tab. icon on the Navigators toolbar.)

(Unix users, choose the Model Navigator

The feature that was created for the length (LENGTH_EXP(17)) was obviously created after the blend that you had to suppress. It must, however, be built before the blend, so the blend does not affect the value of the length.

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Reorder LENGTH_EXP(17) so that it is created before BLEND(10)

On the LENGTH_EXP(17) node, use MB3 Reorder Before BLEND(10). Use Information Feature to find the expression name that controls the depth of EXTRUDED(4). Make a note of it. Choose Information Feature. Turn the Display Dimensions switch on. Select EXTRUDED(4) from the Filter list. Note the "p" value for depth (p9=58.000) displayed in the graphics area.

Using Geometric Expressions Creating the Hole You need to reveal the datum plane that will be used for locating the holes in one direction. (It is currently blanked). Choose Edit

Blank

Unblank All of Part.

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Choose the Hole icon

icon or choose Insert

Form Feature

Hole.

Choose the Simple icon. Enter the diameter. You will want to define the diameter to be 1/4 of the captured length. (hint: captured length is p37).

Select the planar placement face.

754 Select the thru face.

OK the dialog.

Using Geometric Expressions Positioning Dimensions using Geometric Expressions Now, you are ready to position the holes. Choose the Perpendicular icon

from the Positioning dialog.

Select the appropriate edges to locate the hole. You want to locate the holes so that they are positioned at 1/4 of the depth of the part and 1/2 of the captured edge length. Repeat the appropriate steps until you have created and located all 4 holes on the part.

To see how the location and size of the holes you created are affected, make some changes to the part.

Choose the Edit Feature Parameters icon Select the EXTRUDED(4) feature and OK. Choose Feature Parameters. Change the End Distance to 100.

or choose Edit

Feature

Parameters.

755 OK twice. Select SKETCH_000:SKETCH(3) and OK. The Edit Sketch Dimensions dialog is displayed.

Select p1 and change its value to 200, and press Enter. Select p2 and change its value to 60, then press Enter and OK. OK the Edit Parameters dialog. Choose Edit

Blank

Blank, select the datum plane and OK.

Notice how the size of the holes and their locations were affected by the changes made.

Using Geometric Expressions Editing Geometric Expressions Unlike other expressions, Geometric Expressions can only be edited with the Edit operation.

Choose the Edit Parameters icon

or choose Edit

Feature

Feature

Parameters.

Choose the LENGTH_EXP(10) feature, then OK. The Edit Length Feature dialog is displayed. The options on this dialog are the same options that are available on the Geometric Expression dialog.

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The current value of LENGTH_EXP(10) was determined by selecting the edge of the flange, so now you have the opportunity to reselect a different entity for a new corresponding value. Select a new line that will depict a different length.

OK the Edit Length Feature dialog. Apply in the Edit Parameters dialog. Note the changes to the model based on the changed geometric expression.

Using Geometric Expressions Deleting Geometric Expressions In the Model Navigator, select the LENGTH_EXP(10) node, then MB3

Delete

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The Geometric Expression has been deleted. Close the part. You can use Information Expression to get additional information on geometric expressions. List All Geometric provides information about the geometric expressions only. For additional information, please refer to the Gateway Online Help.

Using Geometric Expressions Interpart Expressions There are a few things to be aware of when you begin to work with assemblies. Interpart Expressions (IPEs) allow you to establish relationships between expressions in separate part files. By using interpart expressions, a change to an expression in one part file can change the value of an expression in a separate part file, thus altering the geometry of that part. Interpart expressions are used between assemblies and component part files, and it requires a good understanding of Assemblies before you can use them to best advantage. Please refer to the Advanced Assembly Modeling CAST course for more information on Interpart Expressions.

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Using Expressions In this lesson, you will learn about: importing and exporting expressions using the filtering options renaming and deleting expressions adding descriptive comments to expressions

Exporting / Importing Expressions You can export expressions from Unigraphics NX into an ASCII text file. You can also import expressions from ASCII text files back into Unigraphics NX. Why Export / Import? The Export/Import function can be used to: Export the expressions into an ASCII text file. Edit the existing expressions in the text file to the correct values, and create any new expressions that are required for the model. Import the expressions back into the part and update the model. When a large number of expressions need to be edited or created, it is easier to make those changes in a text file then import them back into the part file.

Exporting / Importing Expressions Exporting Expressions The Export option writes the expressions to an ASCII text file where it can be reviewed and edited. Choose File Directory.

Options

Load Options and make sure the Load Method is set to From

Open part file exp_wrench.prt from the exp subdirectory. This part contains expressions used to control the parameters of this model. Enter the Modeling application.

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Choose the Modeling icon Application Modeling Choose Tools

from the Application toolbar or choose

Expression.

Choose the Export icon. The Export Expression dialog is displayed. You are prompted to specify the name of the file you want to export and to set an export option. Notice the available export options: Work part exports all expressions in the work part All in assembly tree exports all expressions in the work part plus all of its components (assy tree) All parts exports all expressions in all parts in the session Since you do not have write access in the current directory you will not be exporting any expressions for this lesson. However, for future reference, the export procedure is as follows: Choose the Export icon from the Expressions dialog. Define which expressions you want to export by choosing Work Part, All in assembly tree, or All parts. Specify the directory and the name of the file to be created. Files used for Importing / Exporting expressions contain the .exp file extension. OK the dialog. The ASCII text file would then be written to the disk. Geometric Expressions become 'dumb' expressions when they are exported. For example, the geometric expression, p46=length(21) that currently evaluates as 1.5 becomes p46=1.5 in the exported file. Cancel the dialog.

Exporting / Importing Expressions Importing Expressions In this section, you will import the expressions needed to parameterize a combination wrench. These parameters will allow you to control the size, length and the angle of the open end wrench. Choose the Import icon

on the Expressions dialog.

The Import Expression dialog is displayed. You are prompted to choose the file you want to import and to set an import option. The import options are as follows: Replace existing reads the specified import file and attempts to add each expression to the table. The system replaces any existing expressions in your expression table with imported expressions that bear the same names.

760 Keep existing also reads the specified import file and attempts to add each expression to the table. If the system finds any conflicts (expressions with the same name) during transfer, you will get an error message. Delete imported removes multiple expressions from your part file. The system deletes any expression in the part file that has the same name as the expression in the text file.

Geometric Expressions cannot be imported. Choose wrench.exp from the exp directory. Remember, files used for Importing / Exporting expressions contain the .exp file extension Make sure that the Import option is set to Replace Existing. By setting the Import Options to Replace existing, any expressions being imported with the same name will be superseded by the expressions contained in the Import file. OK the dialog. Change the List By option to Name (if necessary). The expressions from the ASCII file have been added to the part: Expression

Description

Angle=30

Angle of open end

Length=Width*7.5 Handle Length Offset=3

Wrench head offset

Size=18

Wrench Size

Thkns=Size/4

Handle Thickness

Wdth=Size*1.2

Handle Width

p0=Length p1=Width p2=Thkns p3=Thkns p4=1 p5=1 p6=.8 p7=26 p8=Thkns p9=0 p12=Offset p13=Offset

761 p14=Offset p15=Offset p16=Size p17=Size*(1+2/3) p18=0 p21=Size+2 p22=Size/2 p23=Size p24=Size/2 p25=Size*2/3 p26=0 p30=Angle p31=25 p32=.8 p33=25 p34=1 p35=1 p36=Size/2+3 All expressions starting with "p" replaced existing expressions with the same name. Examine the list of expressions and notice that new expressions have been added to the part (such as Angle, Length, Offset, Size ...) and others have been changed. Use Apply to see any changes that resulted from the imported expressions.

Notice the size of the wrench has changed along with the angle of the open end wrench. It might help if you looked at the sketches that were used to create the open and closed ends of the wrench. Choose Edit

Sketch.

Select OPEN_END from the Edit a Sketch dialog, then OK.

762 If the text in the sketch is too small, you can change it using Preferences

Sketch.

Notice that all of the non-angle sketch dimensions are defined in some way by the value of "Size". (These references were made when you imported the new expressions.)

Choose CLOSED_END from the Sketch Name pull-down.

Again, the dimensions on this sketch also rely on the value of "Size".

Choose the Finish icon. Choose Tools

Expressions.

763 To show you how this works, change some of the parameter values to create a different size wrench. Change the following expressions to the new values: Angle=30 Change:

Length=Width*7.5

Angle=90 To:

Length=Width*1 2

Size=18 Size=24 Apply to update the changes to the model. Use MB3

Fit if needed.

Play around with the three expressions (Angle, Length, and Size) to create variations of the wrench. Continue to the next section.

Filtering Expressions Before you continue, examine the Filter option that allows you to display a list of expressions containing specific strings. By using the Filter you can simplify the list of expressions in the Expressions dialog.

You can use the filter to list only those expressions you want to work with. You can also use the filter to filter out the expressions that you do not want listed, by setting the Filter action to Exclude.

764 Key in *Size* into the Filter field, then press Enter.

The two asterisks (*) in this filter are used as wild card characters, just as they are used in most operating systems. The filter *Size* will match any text that begins with any number of any character(s) followed by the string "Size" followed again by any number of any characters. The filter string is case sensitive, the string "Size" is not the same as "size". Now, only those expressions that match the filter *Size* are listed.

Change the Filter Action option to Exclude. Notice that the list now contains only those expressions that do not match the filter *Size*. Change the filter action back to Include. Key in *Offset* in the Filter field, then press Enter. This time only the expressions that match the filter *Offset* are listed.

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Deleting Expressions When an expression is deleted, it is removed from the part. Expressions cannot be deleted when they are still being used. This means that: the expression is being referenced in the definition of another expression the expression is used to define a parameter or position of a feature or sketch Keep in mind that Geometric Expressions cannot be deleted via the Expressions dialog as with other expressions; they are deleted using the Model Navigator. Choose the expression Offset=3 from the list. Choose the Delete icon

from the bottom of the Expressions dialog.

This expression cannot be deleted because it is being referenced by other expressions. An Information window displays with a list of all the expressions referencing the expression "Offset". OK the message dialog and dismiss the Information window. Choose p12=Offset. Choose the Delete icon

on the Expressions dialog.

This time the expression "p12" is being used to define a feature parameter. Again, a message box displays to inform you that expression "p12" is still in use. An Information window is also displayed with a Used-by report.

766 In this report, it tells you that the expression is being used in DATUM_PLANE(3) as a "Positioning Dimension Offset". OK the message dialog and dismiss the Information window. Change p12 to 3. Change p13 to p13=p12. Change p14 to p14=p12. Change p15 to p15=p12. Choose Offset=3 from the list. Choose the Delete icon

on the Expressions dialog.

Because "Offset=3" is no longer being used, the system deletes the expression. Also, because the string "Offset" is no longer in any expression, the list is left empty. Key in *p12* in the Filter field, then Enter. All expressions containing the string "p12" are displayed in the list.

Renaming Expressions When an expression is renamed, the name is changed not only in the expression itself (left side) but also in all other expressions that reference that expression (right side). Choose p12=3. Choose the Rename icon. The Rename dialog displays and you are prompted to enter a new name for the expression. Key in Offset for the new name, then press Enter. The expression "p12" is renamed to "Offset" and all other expressions referencing it are also changed. Key in *Offset* in the Filter field, then Enter. Note the replacement of "Offset" for all the "p12" variables.

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Using Comments in Expressions You can create comments in expressions using double forward slashes "//" before the actual comment. The double forward slashes indicates to the system that whatever follows is to be ignored. Comments cannot exist alone on a line, and they must always follow an expression.

Choose the expression Offset=3 from the list. Key in the comment // Wrench Head Offset after the expression.

Press Enter. The comment is now displayed in the list.

Calculator Capabilities You can use the expression editor field to perform calculations.

You may then copy the value into an actual expression. If you key in an arithmetic statement without an expression name, the system will evaluate your statement and display the value. For example, entering the following expression in the editor field will create a new expression:

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However, if you had entered:

No expression is created, because no name (left side) is given in your statement. The system would evaluate the statement, and display the value as:

The statement can then be made into an actual expression. You can also key in a statement in scientific notation. The value you key in must contain a positive or negative sign. For example, you can enter:

Key in Offset+1 in the editor field then press Enter. Because no variable name was given, the system did not create an expression. Notice that the value of the statement is still displayed.

Notice also that the expression "Offset" can still be referenced by the expression statement. Think of some other statements and key them in the editor field.

Listing Expressions You can get specific information from expressions by listing them in a Information window. Key in an asterisk (*) as the filter, then press Enter, so that all expressions are listed. Choose Information

Expression

List All.

The Information window is displayed with a list of all the expressions and their current values.

769 You could save this information to a text file by choosing File Save As from the Information window menu bar. You could also print the list to your default printer, without saving it, by choosing File Print. This same list can also be retrieved by choosing List from the Expressions dialog. You can also list expressions in multiple parts by choosing List All in Assembly or List All in Session. Additional information about the geometric expressions in the part can be obtained by the List All Geometric option. Dismiss the Information window. Choose Information

Feature.

With the Feature Browser dialog you can list all the expressions associated with a selected feature. Choose the feature which expressions you want to list. Choose BLOCK(0) from the list of features. Be sure the List option is set to Expressions, and use OK. The Information window is displayed with a list of all expressions used to define the block feature. Any expressions being referenced by these expressions are also listed.

Dismiss the Information window. Choose Information

Expression

List By Sketch.

Choose OPEN_END:SKETCH(10) from the list of sketches, then OK. The Information window is displayed with a list of all expressions used or referenced in the selected sketch. Dismiss the Information window.

770 Choose Information

Expression

List All By Reference.

The Information window is again displayed, this time with a list of all expressions and any expressions they are Referencing. Dismiss the Information window.

Cut and Paste In Unigraphics NX, you can Copy, Cut or Paste any text. This can be done between any two entry fields or between an entry field and the Information window. How to use Cut and Paste: Highlight the statement in the editor field by double-clicking or by click-and-dragging over the text. With the cursor inside the editor field, hold down MB3 and choose Copy or Cut.

From the expression list, double-click on the expression you want to add the text to. Then position the cursor where you want to insert the text, hold down MB3 and choose Paste. You can also copy text from the Information window and paste it into an entry field. Close all part files.

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Using Spreadsheet The objectives of this lesson are: to introduce you to spreadsheet types and preferences to learn to edit spreadsheet data to learn how to add expressions to a spreadsheet to learn how to modify parts by editing spreadsheet expressions to create a family of parts using a spreadsheet to use Goal Seek with spreadsheets to meet design criteria This lesson uses the Excel format for spreadsheet activities. However, both Excel and Xess spreadsheet formats operate in a similar fashion. Any differences will be drawn to your attention at the time.

Spreadsheet Types and Preferences Important Notice to Windows Users To be able to do this lesson, you must be view CAST outside of the Resource Bar Training tab, in a separate browser. This is because in this lesson, when a Spreadsheet is opened, Unigraphics NX is locked as is the browser embedded in Unigraphics NX . There are two types of spreadsheet formats available in Unigraphics NX, the Excel spreadsheet in Windows format and the Xess spreadsheet in Unix. You can control which spreadsheet format you want to use by using the Spreadsheet Preferences dialog. You can also migrate data between the two different formats. You can run Xess on Windows if you have Exceed installed and running on your workstation. Without Exceed installed, Xess will not run.

Spreadsheet Types and Preferences Setting the Spreadsheet Preferences [Windows Only] On Windows, you have the option of using either Xess or Excel. You can set one of these as the default set on the Spreadsheet Preference dialog. Choose Preferences

Spreadsheet.

The Spreadsheet Preferences dialog appears.

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Select Excel and OK the dialog. Now each time you use the Tools Spreadsheet.

Spreadsheet command, it will bring up an Excel

Spreadsheet Types and Preferences Migrate Spreadsheet Data On Windows, you can convert an Xess spreadsheet into Excel. On Unix you can convert an Excel spreadsheet into Xess, or vice versa. Some clean up of the resulting spreadsheet may be required. Important Notice to Unix Users You do not need to have access to the spreadsheet where the data is stored, only to the spreadsheet that you are migrating to. Choose File Directory.

Options

Load Options and make sure the Load Method is set to From

Open part exp_adjst_wheel.prt from the exp subdirectory. Choose File

Utilities

Migrate Spreadsheet Data.

The Migrate Spreadsheet Data dialog appears.

If there was a spreadsheet associated with this part, you could select the specific format from the appropriate drop down menu and OK the dialog. At that point, the Information Window would display.

773 When the operation is complete, an Info dialog will appear for you to OK. The Information window will also confirm that the spreadsheet was converted to the specified format. Opening Xess spreadsheets on Windows using Unigraphics NX requires the Hummingbird Exceed product. When moving Unigraphics NX parts containing spreadsheet data in Excel format between different installations of Unigraphics NX, links to Unigraphics NX/Excel spreadsheet functions (such as MASS3D) may become invalid, so you may have to manually reenter formulas with the Unigraphics NX/Excel functions.

Cancel the dialog.

Using Spreadsheet Edit The Spreadsheet Edit option allows you to edit expression values from within the Spreadsheet. These changes are then added back into Unigraphics NX where you can then update the part geometry from the Expressions dialog. Continue using exp_adjst_wheel.prt.

Choose Application

Modeling, then choose Tools

Expression.

If necessary, key in an asterisk (*) as the filter and press Enter, so all the expressions are listed. Choose the Spreadsheet Edit icon

from the Expressions dialog.

The spreadsheet is opened with all the expressions from the part listed in it. The only cells of this spreadsheet that can be modified in any way is the Formula column.

774 It should be noted that Geometric Expressions do appear in the spreadsheet but they cannot be edited through the Spreadsheet Edit function. Please refer back to the Creating Expressions lesson for more information on creating and editing Geometric Expressions. This column is where you can make changes to any of the expressions in the current part file. Your spreadsheet may appear slightly different with expressions in a slightly different order. Make the following changes to the expressions in column B of the list:

From the spreadsheet menu bar, choose Tools

Update Expr.

The update expression function transfers all the data from the spreadsheet back into Unigraphics NX. This operation does not update the part geometry. To update the part, you need to return back to Unigraphics NX and Apply the changes from within the Expressions dialog. Choose File

Exit from the spreadsheet menu bar.

Notice that the changes you just made in the spreadsheet are now reflected back to the list in the Expressions dialog.

Choose Apply from the Expressions dialog. The part geometry is updated.

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Close all parts.

Adding Expressions to a Spreadsheet In this section, you extract expressions from a Unigraphics NX part file, list them on the spreadsheet, then edit their values and update the part. Open part exp_gear_sprd.prt from the exp directory.

Go into the Modeling application. Choose the Modeling icon Application Modeling Choose Tools

from the Application toolbar or choose

Expression.

The Expressions dialog is displayed. The following expressions are the critical ones in this activity. Hole_dia - Diameter of the center hole Key_length - Length of the center key hole Key_width - Width of the center key hole N - Total number of teeth on the gear

776 P - Teeth per inch Thickness - Gear Thickness hub_dia - Diameter of the center hub hub_height - Height of the center hub You can leave this dialog up as you work on the spreadsheet. Choose Tools

Spreadsheet .

A new (empty) spreadsheet is displayed. Once the spreadsheet is invoked, your Unigraphics NX session is locked. You are not able to work directly in Unigraphics NX until you leave the spreadsheet. Unigraphics NX and the spreadsheet are now connected so they can pass information back and forth. For this reason the spreadsheet needs to have control of your Unigraphics NX session. Whenever you need to work in Unigraphics NX, you can disconnect this link, then reconnect when you are ready to return back to the spreadsheet. Move and resize the spreadsheet window so you can see these instructions.

Adding Expressions to a Spreadsheet Extracting Expressions The first thing you want to do is Extract the expressions from the part and place them in columns B and C. In the Spreadsheet, choose cell B2.

From the menu bar of the spreadsheet, choose Tools

Extract Expr.

All the expressions from the part file are added to the spreadsheet. The first column contains the Parameters and the next column contains the parameter values.

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Adding Expressions to a Spreadsheet Editing the Spreadsheet The next step is to remove all unnecessary expressions from the list and reorder the remaining expressions. The idea here is to keep only the expressions that need to be modified to make a change to the gear. Use Edit Clear Contents to clear cells B3 - C3 and B9 - C9. Then clear all the cells below row 12 (starting with row 13), remember you can clear all highlighted cells at one time. Your spreadsheet should now look like the illustration below.

To make your work easier, reorder the remaining expressions into a more sensible order.

778 Reorder each row to the order shown below:

Use the Insert or Move operation from the spreadsheet to make these changes (use the Edit pull-down menu or use MB3 in the cell area). More About: Moving Data From One Cell to Another

For Excel Spreadsheets: Highlight the cell(s) you want to move. Choose Edit Cut or MB3 Cut. You will see "marching ants" around the cells. Choose the cell you want to move the data to. Choose Edit Paste or MB3 Paste. For Xess Spreadsheets: Highlight the cell(s) you want to move. Choose Edit Move or MB3 Move. Choose the cell you want to move the data to. The data in all the cells you highlighted is moved to the same relationship of cells beginning with the one you chose. (Any existing data in those cells will be overwritten.) (You can also do this with the MB3 Pop-Up Window.)

Next, you can add a verbal description to each parameter. First, you need a heading. Here is a quick way to setup a cell if you already have the correct format elsewhere.

779 Copy the value of cell B2 (the "Parameters" title). Paste it into cell A2. Edit cell A2 to say "Description".

Now you are ready to enter all the verbal descriptions for the various parameters. Remember that when you key alphabetic characters into these cells, they retain their "default" format. Widen column A to 20 units wide. More About: Changing the Width of a Column by Keying in a Value

For Excel Spreadsheets: Choose the column head of the column you want to change. The whole column highlights. Choose MB3 Column Width Enter the width value you want, then OK. For Xess Spreadsheets: Choose the column head of the column you want to change. The whole column highlights. Choose Format Column Width Column Width. OR MB3 Column Width Column Width. Dialog: Column Width Optional: You can use the options on this dialog to assign the default width or snap the column to its widest cell. Key in the column width value you want to use.

Remember when adding information into a cell:

780 Choose the cell to edit (use MB1 or the down arrow key). Type the text for that cell, then press Enter. Add the following descriptions to Column A.

Once again change the width of the cell. Change the width of column A again, this time snapping its width to its contents. More About: Changing Column Width by Snapping it to its Contents

For Excel Spreadsheets: Choose the column head of the column you want to change. The whole column highlights. Choose Format

Column

AutoFit Selection

For Xess Spreadsheets: Choose the column head of the column you want to change. The whole column highlights. Choose Format Column Width Snap Width to Content. OR MB3 Column Width Snap Width to Content. The column adjusts to the width of the characters in the widest cell.

Changing the Part by Editing Expressions in a Spreadsheet

Now you are ready to edit the expressions and update the part file.

781 Change the following expression values: Total Number of Teeth = 40 Gear Thickness = 10 Hub Diameter = 35 Hole Diameter = 20

You are now ready to update the Unigraphics NX part file. Move the spreadsheet to the bottom of the screen so you can see most of the gear. Choose Tools

Update UG Part from the spreadsheet.

All the data from the spreadsheet is passed back into Unigraphics NX, this data is then used to update the part file.

Because you are currently working in the spreadsheet and it is connected to Unigraphics NX, the spreadsheet has control of your Unigraphics NX session (this is the reason you can't work directly in Unigraphics NX without first disconnecting this link). If you need to break the connection between the spreadsheet and Unigraphics NX: Excel Spreadsheet: You must save your spreadsheet then exit; to reconnect use Tools Spreadsheet in Unigraphics NX and accept the message that asks if you want to use current data. Xess Spreadsheet: choose Connections Disconnect from the spreadsheet pulldown menu; to reconnect, choose Tools Spreadsheet in Unigraphics NX. Close all parts

Creating a Family of Parts Using Regular Spreadsheet Functions In the previous example, you used the spreadsheet to change expression values, and update those values in a single part file.

782 In this example, first you create a family of gear parts with three members. You then save each of these family members into a separate part file.

The method you are following here is different than the Part Families operation found within the CAST Advanced Assembly Modeling lesson.

Creating a Family of Parts Using Regular Spreadsheet Functions Initiating and Preparing the Spreadsheet Open part exp_gear_sprd_fam_prts.prt from the exp directory.

Go into the Modeling application. Choose the Modeling icon Application Modeling Choose Tools

Expression.

Choose Tools

Spreadsheet .

from the Application toolbar or choose

To start creating a family table, copy the column of values from column C to the columns D and E.

783 Copy all the values in column C to column D.Then copy the same values into column E. More About: Copying and Pasting the Contents (Formulas) of Cells

WARNING: If you copy information from more than one cell, it will overwrite (replace) any information in similar cells you are pasting to. Highlight the cell(s) you want to copy information from. MB3 Copy Copy Formula Choose one cell where the information is to be pasted. If you've copied information (formulas) from more than one cell, the system will paste it all in starting with the cell you chose. Also: the copied information does NOT remain in the buffer. (You can continue to paste this information in other cells. You must copy it fresh each time.)

Creating a Family of Parts Using Regular Spreadsheet Functions Creating a Family of Parts This family table now contains one column for the parameter names (Column B), and three to contain values for different variations of those parameters (Column C, D, E).

By changing the parameter values in the different columns, you can define a family of parts where each column contains the data for one member of the family. Key in the titles Gear 1, Gear 2 and Gear 3 on the top of columns C,D, and E. Create these titles in the same format as the "Parameters" title. Hint: Try copying the contents of cell B2 into the other cells, then change the text.

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Now edit the parameters of the three gears. Make the following changes to the Family Table.

Creating a Family of Parts Using Regular Spreadsheet Functions Defining the Expression Range The spreadsheet Expression Range is a group of cells that defines the area of the spreadsheet that contains the active block of Unigraphics NX data. In order to affect changes on the part, the Expression Range needs to include at least the expression names. When expressions are extracted from Unigraphics NX, the Expression Range is set up for you. Choose cells B3 through E10. (These cells are highlighted.)

To define the new Expression Range, choose Edit spreadsheet menu bar.

Define Expr Rng from the

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Creating a Family of Parts Using Regular Spreadsheet Functions Setting Unigraphics NX Preferences You need to specify that you are using the mouse to define a subset area of the Expression Range as the source for the updated data sent to Unigraphics NX. Choose Options

UG Preferences from the menu bar of the spreadsheet.

Turn the Use Fixed Update Range option off, then OK the dialog. Whenever you elect to update the part, the Expression Range definition and optionally the active cell position determine what data is sent to Unigraphics NX.

Creating a Family of Parts Using Regular Spreadsheet Functions Updating the Part Now that you have created the family table and have turned the fixed update range off, you can proceed to update the part using the data you entered into the table. Select all the expression values in column C.

Choose Tools

Update UG Part from the spreadsheet menu bar.

786 The parameter values for gear 1 are passed back into Unigraphics NX, and the part file is updated.

The status line tells you that the update has been successful. Notice that the number of teeth, and teeth per inch, on the gear have changed along with the thickness of the gear and the size of the hub. N=25

Number of Teeth

P=.2

Teeth Per millimeter

Thickness=40 Gear Thickness hub_dia=35

Center Hub Diameter

Hole_dia=20 Center Hole Diameter Now repeat the process to update the parts using the data from column D.

Once again the number of teeth, and teeth per inch has changed along with the thickness of the gear and the size of the hub. N=40

Number of Teeth

P=.16

Teeth Per Millimeter

Thickness=15

Gear Thickness

hub_dia=120

Center Hub Diameter

hub_height=3.8 Center Hub Height

787 Repeat the process once again for column E.

Once again the number of teeth, and teeth per inch has changed along with the thickness of the gear and the size of the hub. N=60

Number of Teeth

P=.4

Teeth Per Millimeter

Thickness=20 Gear Thickness hub_dia=35

Center Hub Diameter

hub_height=10 Center Hub Height

Creating a Family of Parts Using Regular Spreadsheet Functions Saving a Family of Parts into Separate Part Files Up to this point you have created the family table, and set up the expressions for the different gears. Take this activity one step further by assigning each of these family members a part name and saving them to disk. In order to have the system create the family members in separate part files, you need to define both the location of the part (what directory), and the name of the part file. This information needs to be added to the bottom row of the family table.

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When you enter the file name for the family member, you do not need to add the extension ".prt", it is automatically added when the part is saved to disk. In the cells C11 - E11 key in the names of the part files to be created for this family of parts. Use gear1, gear2, and gear3 for the part names. Remember to begin the part name with the path of a directory where you have write access (ex: /disk1/gear1).

Do not be concerned if the path name runs longer than the width of the cell. If it is a valid path name, the part is created.

Creating a Family of Parts Using Regular Spreadsheet Functions Defining the Family Range The next thing you need to do before you can save the family members to disk is to define the range that is used for this family of parts. Select cells B3 - E11.

789

Choose Edit

Define Fmly Rng from the menu bar of the spreadsheet.

Now that the family range has been defined, you can let the system use the data in this family table to create a separate Unigraphics NX part file for each family member. Choose Tools

Build Family to update each part and save it into its own part file.

Each of the three parts are updated in Unigraphics NX and saved to disk in the part file you specified. Feel free to continue to experiment with these parts. Exit the Spreadsheet and then close the parts when you are finished.

Goal Seek The Goal Seek operation is used when you want to make a specific cell value converge to a specified target value. This is done by changing a variable parameter, then comparing the target value with the value of the target cell. While the value of the target cell is not equal to the target value, the variable parameter is changed and the comparison is made again. This is done until the value of the target cell is equal to the target value (within the specified tolerance).

Goal Seek Goal Analysis Another operation used in conjunction with Goal Seek is called Goal Analysis. This function creates a graph of the output of the Goal seek operation.

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You can use this graph to find good initial values for the Goal Seek or to help you better understand how the expressions respond to the changes in the input. Windows users open part exp_guide_plate.prt from the exp directory. Unix users open part exp_guide_plate_unix.prt from the same directory.

Go into the Modeling application. Choose the Modeling icon Application Modeling

from the Application toolbar or choose

Choose the Edit Pre-V13 Sketch icon (it can be found on the Form Feature toolbar; use View Toolbars Customize as necessary).

For this example, the specifications for this part require the distance between hole 1 and hole 2 to be 7 inches, it is currently 8.018.

791 Examine th sketch to note that there is only a reference dimension between the two holes. (Remember that a reference expression cannot be edited. To reach that value, use Goal Seek to change the Value of expression "h2_lgth" until the distance between the holes is at the desired value. Choose Tools

Spreadsheet.

This Spreadsheet contains all the expressions needed to perform both the Goal Analysis and the Goal Seek. Columns B and C contain all the critical expressions that are driving this part.

The middle columns contain positions that define the center points of the two holes.

This information is obtained by using the "POINT" function to retrieve information from the Unigraphics NX part file. Choose cell F3 in the spreadsheet. Notice that in the edit field at the top of the spreadsheet the following is displayed: =@POINT("hole1") In this function, the variable "hole1" is the name attribute of one of the circles in the sketch. The data in column J and K calculates the distance between the two hole locations. This calculation is done with the "DISTPT" function.

792 Choose cell K3. This formula is displayed in the edit field. =@DISTPT(F3..H3,F4..H4) The two parameters used in this function are cells containing the XYZ coordinates for the two points that are to be evaluated.

Goal Seek Setting Up the Goal Seek Operation The first thing you need to do is specify what kind of analysis solving technique is to be used for this Goal Seek operation. Choose Options

Setup Goal Seek from the spreadsheet menu bar.

There are five different analysis solving techniques available to you: Regula Falsi Method Newton - Raphson Newton - Raphson 2D Nonlinear Sidel 2D Optimize 1xN The specifics of these techniques are beyond the scope of this lesson. If you want to learn more about them, see the Gateway portion of the Unigraphics NX online help. For this lesson, use the Regula Falsi Method. Make sure that Regula Falsi Method is selected, then OK the dialog.

Goal Seek

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Goal Analysis Next use the Goal Analysis option to get an estimate of what initial values to use in the Goal Seek. Choose Tools

Goal Analysis.

The Goal Analysis dialog is displayed.

The Variable Cell field contains the location of the cell whose value changes throughout the analysis operation. The Target Cell field contains the location where.the results of this analysis is placed. Key in C4 as the Variable Cell and K3 as the Target Cell. Do not press the Enter key yet continue on to complete the next steps.

The Lower and Upper Brackets are the upper and lower bounds that ate used for this analysis. Key in 2 for the Lower Bracket and 8 for the Upper Bracket.

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The Number of Steps is the number of iterations that are to be done in this Analysis run. The Results Cell is the cell where all the results are placed in the Spreadsheet. Key in 15 for the Number of Steps and J10 for the Results Cell. Make sure Perform UG Update is toggled on.

OK to begin the analysis. The analysis is started and runs through 15 different iterations starting at 2 and ending at 8. It may take several minutes for it to complete the operation. These values are listed in the spreadsheet starting in the Results Cell (J10). Notice that the results in column K range from approximately 5.3 to about 10.6.

795 When the analysis is complete, a dialog is displayed with a graph of the values that were used in cell C4 and the corresponding results at cell K3. With this information, you can now estimate that if the distance between the two holes is going to be 7 inches, then the value of C4 has got to be between 3 and 5 inches. These values are then used for the Upper and Lower bracket of the Goal Seek.

Choose Sheet 1 to get back to the spreadsheet data.

Goal Seek Running Goal Seek Next, take this information and use it in the Goal Seek operation. Choose Tools

Goal Seek from the spreadsheet menu bar.

The Goal Seek dialog is displayed. Key in C4 for the Variable Cell, K3 for the Target Cell, and 7 for the Target Value.

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Now key in 3 for Lower Bracket, 5 for the Upper Bracket and leave the other options unchanged.

When all the correct values have been entered, you are ready to start the Goal Seek operation. Before you proceed you may want to position the Unigraphics NX graphics area and the spreadsheet so you can see them as the model is updated. OK the Goal Seek dialog to begin the operation. Examine the sketch and notice that the new value for the expression h2_lgth (cell C4) is now about 4.083 and the distance between the holes is now close to 7 inches (within the specified tolerance).

Close both the spreadsheet and the part file when you are done.

Using the Visual Editor

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The objectives of this lesson are: to understand why you would use the Visual Editor to learn to work with sketches in the Visual Editor to learn to import data into the Visual Editor to learn to edit expressions in the Visual Editor to learn to work with drawings in the Visual Editor

Why Use the Visual Editor?

798 The Visual Editor provides a static graphical representation (cartoon) of a model with its corresponding dimensions and expressions. You can create your cartoons by importing sketches or drawings to the Visual Editor. You can use the cartoon to edit object parameters by editing the expressions in the Visual Editor. Edits that you make to your cartoon are used to update your model in Unigraphics NX. The Visual Editor is a useful tool particularly when working with complex models. The ease of editing expressions from the cartoon can prove to be an efficient method for updating your model.

Working With Sketches For this activity, you will add a sketch to the Visual Editor, change some of the expressions, and then update the model. Choose File Directory.

Options

Load Options and make sure the Load Method is set to From

Open part file exp_coupler1.prt from the exp subdirectory.

Choose the Modeling icon Modeling Choose the Sketch icon

from the Application toolbar or choose Application

from the Form Feature toolbar or choose Insert

Sketch.

Choose SKETCH_000 from the Sketch Name pull-down.

The sketch is displayed. Some of the less important dimensions have been blanked to simplify the sketch.

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Working With Sketches Preparing Sketches for the Visual Editor Because the imported graphics (cartoon) will look exactly like the Unigraphics NX graphics area, it is important that you prepare the graphics area to look just the way you want the cartoon to look before importing it into the Visual Editor. You will not be able to edit this cartoon while in the Visual Editor, but you have the ability to re-import the graphics to update the cartoon. Keep in mind, your cartoon is simply a static image that you reference while editing. When you import a sketch or drawing with dimensions displayed, the cartoon will also contain those dimensions.

The imported expressions are added to the Visual Editor. They are presented in the expressions list.

These expressions are also referred to as Chart Expressions. When using a sketch, there are several sketch preferences that need to be set so that the cartoon will import correctly. Choose Preferences

Sketch to display the Sketch Preferences dialog.

Set the Dim. Label option to Name and set Retain Dimensions on.

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OK the Sketch Preferences dialog. By setting the Dim. Label to Name, the name of the dimension will be displayed rather than the value, also the sketch dimensions will be displayed in the graphics area when you are working in the Visual Editor.

Move dimensions, as necessary, to improve the display of the dimensions for the Visual Editor. Choose the Finish icon. Orient View to the Top view. The sketch dimensions should still be displayed in the graphics area.

Working With Sketches Importing into the Visual Editor You are now ready to open the Visual Editor and add the new cartoon to it. Choose Tools

Visual Editor.

801 The Visual Parameters Editor is displayed. Import the image into the Visual Editor with the dimensions and the corresponding expressions. Choose Import Image from the Visual Editor window.

Two things should happen at this point. First, the cartoon is imported into the Visual Editor just as it appears in the graphics area.

Second, the dimensions that are displayed by name are added to the cartoon with all the corresponding expressions added to the chart.

802

Working With Sketches Editing Expressions in the Visual Editor You can now edit any of the imported expressions by either selecting the expression name from the cartoon, or selecting the expression from the list of Chart Expressions. From within the Visual Editor, choose the length dimension by clicking on the text p28.

When you click on the dimension text, the corresponding expression in the chart is highlighted, you can now change the value of that dimension.

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1) Fields that can be edited Change name from p28 to length and tab to the value field. Change the value of the expression length to 6, then press Enter. The change is made in the chart but the model is not yet updated. Change the value of the expression rightend to 1.5, then press Enter. Choose Update in the Visual Editor to update the model.

This updates the model in the graphics area, but not in the Visual Editor. Notice that your cartoon remains unchanged. After you update the model, you can update the cartoon by re-importing the image into the Visual Editor. Choose Import Image to re-import the image into the Visual Editor. OK the Confirmation dialog to complete the import. The new cartoon is added to the Visual Editor with the updated chart.

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Working With Sketches Adding and Removing Expressions You can add or remove an expression from the expressions chart. Choose Add / Remove.

The Add/Remove Expressions dialog is displayed. Note that the distinction between the Part Expressions and the Chart Expressions. Part Expressions are all of the expressions associated with the part. You can add expressions to the Part Expressions list by selecting the expression and then choosing Add.

Chart Expressions are those expressions associated with the displayed Visual Editor sheet. You can remove expressions from the Chart Expressions list by selecting the expression and then choosing Remove.

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You will not be adding / removing any expressions for this activity, so choose Cancel to dismiss the Add/Remove Expressions dialog.

Working With Sketches Visual Editor Sheets The Visual Editor Sheets are comprised of your cartoons and expression lists. The Visual Editor can contain as many as 99 sheets. Examine the Visual Editor Sheet Controls:

Arrows move between sheets Add and Removes sheets

Define relevant User Label and Sheet Title, if desired

Note that the first sheet (Sheet 1) is automatically created when you invoke the Visual Editor for the first time. As subsequent sheets are added, the new sheet will become the current sheet. Experiment with the Add and Remove sheet options by creating some new sheets then removing them. Use the arrow icons to move between your newly created sheets. Cancel the Visual Editor.

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Working with Drawings Besides importing sketches, you can also import drawings into the Visual Editor. To prepare your cartoon from a drawing: While in the Drafting application, create and display your drawing with the dimensions and/or notes using the expressions you want to see in your cartoon. For dimensions, use the Annotation Editor to change them so that only the expression name is displayed. You are now ready to add your drawing into the Visual Editor. Use Import Image to import the contents of the graphics window (your drawing) into the Visual Editor. All of the expressions associated with the dimensions and notes in the cartoon are loaded into the Chart expression list. Close the part when you are done.

Expressions Projects The following three projects are to give you a chance to exercise concepts and techniques that you encountered in the previous lessons. The Cover Plate Hole project exercises expression modification for feature positioning. The Slider Bar Slot project exercises the use of the Spreadsheet to position and modify features. The Slider Bar Holes project lets you work with expressions to work with arrays and automatic positioning when the array changes. In all project there are hints to help you along. In addition, if a particular project is too tough to get through, you can import the expressions using an .exp file and "reverse engineer" the correct approach to take in solving the design challenges.

Cover Plate - Hole

807 This project is specifically designed so that you can complete it on your own by doing some exploring. Tips are provided if you need additional help. Choose File Directory.

Options

Load Options and make sure the Load Method is set to From

Open part file exp_cover_plate.prt from the exp subdirectory. Use expressions to position the hole in the middle of the plate. When the plate is re-sized the hole should stay in the center.

Use what you learned in the previous lesson to analyze the part and determine which expressions need to be modified. If you use Edit Positioning Dimension from the Edit Feature dialog you will be able to see how the hole was positioned. If you need more help, continue on.

Cover Plate - Hole Help for the Hole Here is one technique you can use: First, use Information Feature to determine which expressions define the position of the hole and the length and width of the block. The system will then give you a list of the selected features with any related expressions, including any expressions used to define the position of the feature. When you have identified the expressions that are used to position the hole feature, modify them to be half the values of the length and width of the block. This can be done from the Expressions dialog or from the spreadsheet. If you still need a solution, Import the expressions in cover_plate.exp.

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Slider Bar - Slot This project is specifically designed so that you can complete it on your own by doing some exploring. Tips are provided if you need additional help. Open part file exp_slider_bar.prt from the exp subdirectory. Use the spreadsheet to locate the slot in the center of its placement face on the slider bar.

When the length of the bar changes, or the width of the angled placement face is modified, the slot should automatically be repositioned. Also, if the size of the slot changes the slot should remain centered. Use Edit Positioning Dimension from the Edit Feature dialog to see how the slot was positioned relative to the rest of the part. If you need more help, continue on.

Slider Bar - Slot Help for the Slot Here is one technique you can use: Find the expressions used to position the slot. Also, find the expressions used in the parameters of the slot itself. Notice the positioning dimensions for the slot are referencing the left arc center of the slot, not the center of the slot itself. Examine the sketch and find the expression that defines the width of the angled face. Examine the expressions that define the swept feature to find the expression used to define the length of the slider bar.

809 When you have identified the correct expressions, edit the expressions that define the position of the slot. Edit these expressions so they will always position the slot in the center of its placement face.

If you still need a solution, Import the expressions in slider_bar_a.exp.

Slider Bar - Holes With the slider bar still open, edit the instance array so the holes will be spread evenly along the length of the bar. If more holes are added to the instance array, the distance between the holes should be automatically updated. The distance from the last hole in the array to the end of the bar should always be the same as the distance from the start of the bar to the first hole. Use Edit Positioning Dimension from the Edit Feature dialog to see how the holes are positioned relative to the rest of the part.

If you need more help, continue on.

Slider Bar - Holes Help for the Holes Here is one technique you can use: Find the expressions used to define the instance array. Find the expression used to position the first hole to the left end of the bar. This needs to be the distance from the last hole to the end of the bar.

810 Edit the expression used to define the offset of the instance array. This value should depend on the length of the bar and the distance from the front of the bar to the first hole.

If you still need a solution, Import the expressions in slider_bar_b.exp.

-Feature Modeling FundementalsOverview of Modeling This course covers creating and editing techniques for basic modeling features and operations in Unigraphics NX. Audience This course is intended for designers, engineers, manufacturing engineers, application programmers, CAD/CAM managers, and system managers. Prerequisites If you are not familiar with the Unigraphics NX user interface, you must complete the Unigraphics NX Essentials course before starting this course. Course Contents Overview of Modeling — An overview of the types of geometry that you can use to create

models in Unigraphics NX. It also covers methods of modeling parts. Creating a Support Block — An overview of expressions, blocks, datum planes, holes,

bosses, pads, blends, chamfers, and using boolean operations. Creating a Slotted Fixture — An overview of creating blocks, reference features, sheet

bodies, extrusions, trimming solids, chamfers, blends, and hollowing a model. Creating a Slide Fixture — An overview of creating a line, extrusions, center datum planes,

slots, constant edge blends, offset curves, and rectangular and general pockets. Using Sketches to Build Models — An overview of extruding sketches into solid bodies,

revolving sketches, intersecting bodies, and editing expressions.

811 Creating a Pulley — An overview of creating cylinders, holes, mirror features, datum planes,

and slots. Editing Features — An overview of the basics of editing features in solid models.

Overview of Modeling This lesson will introduce you to creating models in Unigraphics NX. The Modeling application lets you create a mathematical representation of any physical part. The model is always created full size. If you need to scale down the part for the sake of a drawing sheet, that is a simple task. After a model is created it can be analyzed for mass properties, reaction to physical loads, tested for interference with other parts, and many more; analyzed for its appearance by several methods - photorealistic renderings, reflection lines, and more; used to make tools for manufacturing the part; have information attached to it that can be used to convey inspection (and other) requirements, including Geometric Dimensioning and Tolerancing; and used to make a drawing of it with annotations (dimensions and notes), with complete associativity. If the part changes, the dimensions change automatically. You can create a model in the context of its assembly. This method lets you associate features of the part with other parts in the assembly. If those other parts change, so will your part.

Types of Geometry There are basically four types of geometry you can use to create models: points, lines and curves, sheets that have no thickness, and solid, which have length, width, and thickness.

Types of Geometry Points

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Points can be associated with other geometry or not. The are simply stored locations. They are displayed as plus signs.

Types of Geometry Lines and Curves

Curves include lines, arcs, circles, conics and splines. They can be created anywhere in 3D space.

Types of Geometry Sheets

Sheets are objects that have length and width, but no thickness. They are called sheet bodies or surfaces. There are many methods of creating sheet bodies. They are covered in detail in the Free Form Modeling course. Sheet bodies can be created anywhere in 3D space.

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Types of Geometry Solids Solids are objects that have length, width, and thickness. They are called solid bodies. There are many methods of creating solid bodies. They are covered in detail in the this Feature Modeling Fundamentals course and in the Feature Modeling - Additional Topics course.

Modeling Methods This section describes the different methods for creating a model. The method you use depends on the characteristics and shape of the part, as well as the intended use of the model, and the methods you like to use.

Modeling Methods This section describes the different methods for creating a model. The method you use depends on the characteristics and shape of the part, as well as the intended use of the model, and the methods you like to use.

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Modeling Methods Primitives You can create a model with primitive shapes (blocks, cylinders, cones, and spheres), and then unite, intersect, or subtract them from each other to achieve the shape you want. This method, however, is not recommended, because the various features are not associative.

Modeling Methods Block Shaped Parts If the part you are modeling is basically block-shaped, you can start with a block, and then add features, such as holes, pads, bosses, pockets, blends, and chamfers (and more), to arrive at the final part. When done this way, everything is associated — if for example, the block changes, then everything changes with it.

Modeling Methods Cylindrical Shaped Parts If the part you are modeling is basically cylindrically shaped, you can create a cylinder, and add more features to complete the model.

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Modeling Methods Extruded or Revolved Parts If the part you are modeling has a constant section that is moved in a specified direction to generate the basic shape, you can start with a string of objects (curves, edges, etc.) and extrude them into a model. You can then add more features to finish the part.

If the part you are modeling has a constant section that is revolved about an axis, you can start with a string of objects (curves, edges, etc.) and then use the Revolved Body option.

Modeling Methods Swept Parts If the part you are modeling has a constant section that is moved along a path to generate the basic shape, you can sweep a string of objects (curves, edges, etc.) along the path. You can then add more features to finish the part.

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Modeling Methods Parts with Some Irregular Shapes If your part has some faces that are not planar, cylindrical, spherical or conical, you can create the part using any of the above methods, and then use a sheet body to trim the part. You can then add more features to complete the part.

Modeling Methods Parts with Completely Irregular Shapes

If your part has no planar, cylindrical, spherical or conical faces, you can create sheet bodies and then sew them together to create a solid body.

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Modeling Methods Sheet Metal Shapes If your part is basically a sheet metal part, you can start with a set of sheet bodies, and then thicken them. You can then add more features to complete the part.

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Creating a Support Block This lesson provides a series of activities that let you create this model.

In this lesson, you will perform the following: create block features, create expressions, use Boolean operations, create centered and offset datum planes, create a rectangular pad, create bosses, create counterbored holes, create constant, circular edge blends, create single offset chamfers, and create tapers on faces of the model.

Creating the Basic Shape of a Model In this activity, you will create a new part file. Then, you will create expressions that control some of the sizes of the part by a predetermined set of values. The first feature that you will create is a large block that is the basic shape of the model. Then, you will create a smaller block that could be united with the larger to form a pad. This will form the basic shape of the desired model, before details are added.

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Creating the Basic Shape of a Model Creating a New Part File

Unigraphics NX should be running. Create a new Millimeters part file named support_block. (Refer to the Unigraphics NX Essentials course if you are unfamiliar with creating a new part file.) Choose the New icon , or choose File New. Turn on the Millimeters option. Enter the file name support_block and OK the dialog.

Choose the Modeling icon

, or choose Application

Modeling.

In the graphics area, press MB3, choose Replace View, and choose TFR-TRI to change the view.

820 You are now ready to add data to the empty part file.

Creating the Basic Shape of a Model Creating New Expressions

You can use expressions to control some of the sizes of the part by a predetermined set of values. You can create expressions before or after you create model geometry. Expressions are covered in detail in the Expressions course. Choose Tools

Expression.

The Expressions dialog displays.

You need to create the following expressions: lgth = 180 width = 120

821 thk = 40 Key in lgth=180 in the field below the list box.

Press Enter on your keyboard. The expression is now shown in the list box.

In the same manner, create these other two expressions. The Expressions dialog should list these three expressions, when you have finished.

OK the Expressions dialog.

Creating the Basic Shape of a Model Creating the First Block

Blocks can be created by three different methods, however, the Origin, Edge Lengths method is the one used most frequently. Primitives are Form Features. Primitives include blocks, cones, cylinders, spheres, and tubes. As a best practice, you should limit the number of primitives that you use to one per part file.

Choose the Block icon The Block dialog displays.

, or choose Insert

Form Feature

Block.

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Block Creation Methods

Three Block creation methods are located at the top of the dialog.

Origin, Edge Lengths lets you create a block by entering the lengths of the three edges, and specifying a location. All edges will be parallel to the current Work Coordinate System axes, and the lengths will be measured in a positive direction from the specified location. Two Points, Height lets you create a block by entering the height of the block (along the ZC axis), and by specifying two diagonally opposite points in the base of the block (on the plane that will be parallel to the XC-YC plane. All the edges of the block will be parallel to the current Work Coordinate System axes. Two Diagonal Points lets you create a block by specifying two points on corners of two diagonally opposite points of the desired block. This method will automatically define the length, width, and height of the block. All edges will be parallel to the current Work Coordinate System axes.

Choose the Origin, Edge Lengths method. The Point Method options let you specify the origin (location in model space) for the block. You will be locating the block at the WCS (0, 0, 0), which is the default location for the origin; so, you do not need to respecify an origin.

You need to enter positive values (>0) for the Length, Width, and Height in the respective fields, or accept the default values. Key in lgth for the Length (XC) field, key in width for the Width (YC) field, and key in thk for the Height (ZC) field.

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You can only use the Create part file.

Boolean operation, because no other bodies exist in this

OK the Block dialog to complete the block.

Remember, the block was located by default at WCS 0, 0, 0, but you could have located it anywhere you want, by using the Point Method section of the dialog. Each face of the block is aligned with an axis of the coordinate system. Notice also that all the lengths are measured positively from the origin.

Creating the Basic Shape of a Model Moving the WCS

The WCS (work coordinate system) is used as a mobile coordinate system. The WCS is used for construction on specified x-y-z coordinates. All block creation methods depend on the Work Coordinate System. You are going to create another block. It will be easier to locate this block if you change the location of the Work Coordinate System first. Move the cursor over the WCS, until you see the display of the WCS looks like below.

With the WCS displayed as above, double-click on it. Select the handle (small open circle) at the end of the YC axis.

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Key in 50 as the Distance value. Press the Enter key to move the WCS.

Click MB2 to accept the location and cancel WCS Dynamics.

Creating the Basic Shape of a Model Creating a Block that Represents a Pad Choose the Block icon

, or choose Insert

Use the Origin, Edge Lengths

Form Feature

Block.

method.

The Point Constructor dialog can be used for determining discrete point locations, points of intersection, and implied points along a curve.

825 Using the Point Method option for Point Constructor set the location for this block at WCS 0, 0, 0. Choose the Point Constructor icon from the Point Method options on the dialog. Choose Reset on the Point Constructor dialog to change all values to zero.

OK the Point Constructor dialog. Key in lgth for the Length (XC), key in 20 for the Width (YC), and key in 50 for the Height (ZC) field on the Block dialog.

Check that the Create icon Shade

is selected, and OK the Block dialog.

the view.

Close the part file.

Boolean Operations In this activity, you will experiment with Boolean Operations. Boolean Operations let you Unite, Subtract, or Intersect separate bodies. You are going to use each of the Boolean operations, but finally unite two solids to create one solid

826 body.

Types of Boolean Operations

Boolean operations let you combine previously existing solid and/or sheet bodies. You can apply the following boolean operations to existing bodies: The Unite option lets you join solids with solids. You cannot unite a solid body and a sheet body, or a sheet body and a sheet body. The Subtract option lets you subtract one or more tool bodies from a target body. This operation leaves empty space where the subtracted target body existed. The Intersect option lets you create a body that contains the volume shared by two different bodies. You can intersect solids with solids, sheets with sheets, and a sheet with a solid, but not a solid with a sheet.

Boolean Operations Subtracting Solids Open part file fmf1_support_block_1.prt from fmf1 subdirectory, and start the Modeling application.

827 The part contains two separate solid block features. Notice that they occupy some of the same model space. Because of this, you can use Boolean operations to unite, subtract, or intersect these two bodies. You cannot split a sheet or solid body into multiple bodies using the Subtract Boolean operation. You will try to Subtract

Choose the Subtract icon

the smaller solid body from the larger one.

, or choose Insert

Feature Operation

Subtract.

The Subtract dialog displays.

Subtract Dialog Options With the Target Body icon

active, select the larger block.

With the Tool Body selection step active

, select the smaller block.

Leave the Retain Tool, Retain Target, and Confirm Upon Apply turned off, and OK the Subtract dialog. The operation failed.

A the message tells you that a solid body cannot be split into two or more bodies by the Subtract function. Read the message, and OK it. Cancel the Subtract dialog.

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Boolean Operations Intersecting Solids The Intersect function results in the shared volume of the selected Target and Tool bodies. This option lets you create a body containing the volume shared by two different bodies. You can intersect solids with solids, sheets with sheets, and a sheet with a solid, but not a solid with a sheet. An INTERSECT feature is created by this option. Intersect can leave empty space where the intersected target and tool bodies existed. You have the option to save and retain unmodified copies of the target and tool bodies.

Choose the Intersect icon

, or choose Insert

Feature Operation

Intersect.

The options on the Intersect dialog are similar to those on the Subtract dialog.

Intersect Dialog Options

Target Body lets you select a target sheet or solid body that you want to intersect with one or more tool bodies. Tool Body lets you select one or more tool sheets or bodies to intersect with the selected target body. If the target body is a solid body, you can only select solid bodies for the tool. If the target body is a sheet body, you can select either sheet or solid bodies for the tool. Use the Filter to restrict selectable objects. Retain Tool saves the specified tool bodies for the intersect operation. Use this option if you want to save a copy of the selected tool bodies, which remain unmodified. If the Retain Tool option is off, the intersect operation leaves empty space where the tool bodies fail to intersect the target bodies. The Retain Tool option is not available when editing an Intersect feature. Retain Target saves the target body for the intersect operation. Use this option if you want to save a copy of the target body, which remain unmodified. If the Retain Target option is off,

829 the intersect operation leaves empty space where the target body fails to intersect the tool body. If more than one tool body is selected, the boolean operation copies the target of the first boolean feature, but consumes the target bodies for the rest. The Retain Target option is not available when editing an Intersect feature. Confirm Upon Apply lets you preview the results, and accept, reject, or analyze them.

With the Target Body icon

active, select the larger block.

With the Tool Body icon active

, select the smaller block.

Leave the Retain Tool, Retain Target, and Confirm Upon Apply options turned off. OK the Intersect dialog. Notice how the result is the volume shared by the two original selected bodies.

Undo the Intersect operation.

Boolean Operations Uniting Solids

The Unite function makes one body out of selected bodies. The selected bodies normally have to share some volume, or at least share some area of a face. You can unite solids with solids. You cannot unite a solid body and a sheet body, or a sheet body and a sheet body. To unite sheet bodies, we recommend that you use the Sew option. You can also use Sew to unite solid bodies if they have coincident faces. Sewing gives better performance than Unite.

Choose the Unite icon

, or choose Insert

Feature Operation

Unite.

The options on the Intersect dialog are similar to those on the Subtract dialog.

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Unite Dialog Options

Target Body lets you select a target solid body that you want to modify (that is, unite) with one or more tool solid bodies. The target body is united with, and becomes part of, the tool bodies. Tool Body lets you select one or more tool solid bodies to use to modify the selected target body. The tool bodies are untied with, and become part of, the target body. Retain Tool saves the specified tool bodies for the unite operation. Use this option if you want to save a copy of the tool bodies in an unmodified state. The Retain Tool option is not available when editing a Unite feature. Retain Target saves the target body for the unite operation. Use this option if you want to save a copy of the target body in an unmodified state. If more than one tool body is selected, the boolean operation copies the target of the first boolean feature, but consumes the target bodies for the rest. The Retain Target option is not available when editing a Unite feature. Confirm Upon Apply lets you preview the results, and accept, reject, or analyze them.

With the Target Body icon

active, select the larger block.

With the Tool Body selection step active

, select the smaller block.

Leave the Retain Tool, Retain Target, and Confirm Upon Apply options turned off, and OK the Intersect dialog.

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The desired geometric shape has been achieved, but doing it this way lacks associativity. If the larger block were to move, the smaller block would not move with it. Because it is best to have associativity within a model, you should use a pad form feature to build the smaller block shape. Close the part file.

Adding a Rectangular Pad to the Model In this activity, you will create two centered Datum Planes that you will use to locate a rectangular pad on the model. Then, you will create the rectangular pad on the top of the block.

Finally, you will add bosses and holes to the model.

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Adding a Rectangular Pad to the Model Opening the Part Open the part file fmf1_support_block_2.prt from the fmf1 subdirectory, and start the Modeling application.

Several expressions and a block have been created in this part file. Also, the WCS is not positioned at the absolute coordinate system.

Adding a Rectangular Pad to the Model Creating the First Center Datum Plane

Datum planes are a type of reference features. Other reference features include Datum Axes, and Datum Coordinate Systems. Shown below is a Datum Coordinate System which is made up of three Datum Planes, three Datum Axes, a Point, and a Coordinate System object.

Reference Features can be used for placement faces, direction references, trimming a body, or for locating features, and more. You will place datum planes on layer 61. Make layer 61 the Work Layer. You will create two datum planes centered on the block along its length and along its width.

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Choose the Datum Plane icon

, or choose Insert

Form Feature

Datum Plane.

Some icons display in the top left corner of the graphics screen. Select the front face of the block.

The datum plane displays temporarily on the selected face, so you can key in an offset value. Since you want to center the datum plane, and not create an offset datum plane, you can select the back vertical face of the block. Select the back vertical face of the block. The datum plane displays temporarily in the center of the model.

Choose the OK icon from the toolbar in the upper left corner of the graphics window. (You can also use MB2.) The datum plane is now constrained to remain in the center of the model, between the two selected vertical faces.

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Adding a Rectangular Pad to the Model Creating the Second Center Datum Plane Using the same function and methods you did for the first datum plane, create another center datum plane between the two end faces.

Adding a Rectangular Pad to the Model Creating a Rectangular Pad You can now add a rectangular pad to the top of the model, and position it with the datum planes that you just created. You will place the pad on layer 1. Make Layer 1 the Work Layer. Choose the Pad icon

, or choose Insert

Form Feature

Pad.

The Pad dialog lets you create two types of pads: Rectangular, and General. You will be adding a Rectangular Pad. For a Rectangular Pad you must specify the length, width, and height of the pad. You can specify a corner radius if you want rounded vertical edges on the pad. The radius specified must be a positive or zero. A zero radius results in a sharp edged pad. You can also provide a taper angle which is applied to the four walls, which will incline inward. The taper value must be positive or zero. A zero value results in vertical walls.

835 Choose Rectangular. Most form features, like this rectangular pad, must be created on a planar solid face or datum plane. Select the top face of the block as the placement face.

Select the top front edge as the horizontal reference.

The Length, Width, and Height of the pad are defined by the X, Y, and Z directions of the WCS. Corner Radius specifies the radius for the vertical edges of the pad. The radius specified must be a positive or zero. A zero radius results in a sharp edged pad. Taper Angle is the angle at which the four walls of the pad incline inward. This value cannot be negative. A zero value results in vertical walls. Key in lgth for the Length, 20 for the Width, 10 for the Height, and 0 for the Corner Radius and Taper Angle.

OK the Rectangular Pad dialog.

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A temporary pad displays at the position that you selected the solid face. The next step is to position the pad.

Adding a Rectangular Pad to the Model Positioning the Pad

The Positioning dialog displays. You will center the pad on the top of the solid, using the Datum Planes to locate the pad.You will align the centerlines of the pad to the datum planes, using the Line onto Line, and Point onto Line positioning methods.

Line onto Line Positioning

The Line onto Line method creates a positioning constraint dimension the same as the Parallel at a Distance option, but with the distance between the linear edge of the feature or sketch and the linear edge or curve on the target solid set to zero. If you choose a curve when prompted for the target edge, the curve must be linear and must be on the target solid. This positioning dimension causes the feature or sketch to move from its selected edge perpendicularly to the edge or curve selected on the target solid. This constraint only locks the edge on the feature or sketch to the edge/curve on the target solid.

Choose the Line onto Line icon

on the Positioning dialog.

Select the datum plane parallel to the XC-ZC plane as the target edge/datum.

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Select the lengthwise (longest) centerline on the pad as the tool edge.

The model will update after you complete the positioning.

Point onto Line Positioning . The Point onto Line method creates a positioning constraint dimension the same as the Perpendicular option, but with the distance between the edge or curve and point set to zero. The selected point must be on the feature and the line must be on the target solid as an edge, curve, or associated datum plane. This positioning dimension causes the feature or sketch to move from its selected point, normal to the edge or curve selected on the target solid, until the point is on the edge. This constraint only locks the point on the feature or sketch to the edge on the target solid.

Choose the Point onto Line icon

on the Positioning dialog again.

Repeat the process, but this time select the other datum plane, and the other centerline.

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Cancel the Rectangular Pad dialog. Close all part files.

Adding Bosses and Holes to a Model In this activity, you will create offset datum planes.

Then, you will add four tapered bosses on the top of the part. You will position the bosses using the datum planes. Lastly, you will create four counterbored holes in the solid. You will position the holes to the bosses.

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Adding Bosses and Holes to a Model Opening the Part and Setting the Work Layer Open the part file fmf1_support_block_3.prt from the fmf1 subdirectory, and start the Modeling application.

This part contains expressions, a solid, and the two datum planes. You will create the offset datum planes on layer 62. Make layer 62 the Work Layer, and make layer 61 Invisible.

Adding Bosses and Holes to a Model Creating an Offset Datum Plane You will create four datum planes, each offset inward from the four vertical faces of the block. Then, you create other form features, you can position them using these datum planes.

Choose the Datum Plane icon

, or choose Insert

Form Feature

Datum Plane.

Select the left front face of the block.

Notice that the arrow is pointing outward. You want the datum plane to be offset inward 20 millimeters. Key -20 into the Offset field and press Enter.

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Choose the OK icon

from the toolbar in the graphics window.

Adding Bosses and Holes to a Model Creating Three more Offset Datum Planes Repeat the creation process of three more datum planes, so that you have a datum plane offset from each side face. (Be sure that each datum plane is offset by a -20, like the first one that you created.)

Next, you will create and position bosses on the top of the model.

Adding Bosses and Holes to a Model Creating the First Boss As with many other form features, bosses must be placed on a planar solid face or datum plane.

Choose the Boss icon

, or choose Insert

Form Feature

Boss.

You will create the bosses on the top of the block. Select the top face of the block as the placement face. Select it approximately as shown

841 below:

The Boss dialog displays, and a preview of the boss is displayed on the graphics screen.

Key in 24 for the Diameter, 10 for the Height, and 8 for the Taper Angle of the boss.

Apply the dialog.

Adding Bosses and Holes to a Model Locating the Boss

The boss is temporarily located where you selected the top face. You will center of the boss with the two datum planes closest to its current location.

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The Positioning dialog displays. You will use the Point onto Line option to locate the boss.

Point onto Line Positioning

The Point onto Line method creates a positioning constraint dimension the same as the Perpendicular option, but with the distance between the edge or curve and point set to zero. The selected point must be on the feature and the line must be on the target solid as an edge, curve, or associated datum plane. This positioning dimension causes the feature or sketch to move from its selected point, normal to the edge or curve selected on the target solid, until the point is on the edge. This constraint only locks the point on the feature or sketch to the edge on the target solid. . Choose the Point onto Line icon

on the Positioning dialog.

Select one of the datum planes near the boss as the target edge/datum. Choose the Point onto Line icon again. Select the other datum plane near the boss as the target edge/datum. OK the Positioning dialog. The boss is created and positioned.

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Adding Bosses and Holes to a Model Creating and Locating the Remaining Bosses If the Boss dialog is not displayed, choose the Boss icon again. Using the same creation and location methods, create the other three needed bosses.

Make layer 1 the Work Layer and make layer 62 Invisible.

The shaded model looks like this.

Adding Bosses and Holes to a Model Creating Counterbored Holes

844 Next, you will add counterbored holes to the model.

Hole Types

There are three types of holes you can create: Simple, Countersunk, and Counterbored.

Holes must be placed on a planar face (or datum plane), and can be through or not. A hole is made to be a through hole by selecting a plane or face that you want to use to terminate the hole. If a hole is not a through hole, you must specify a depth, and you can specify a tip angle for the bottom of the hole. .

Choose the Hole icon

, or choose Insert

Form Feature

Hole.

The Hole dialog lets you create simple, counterbored, or countersunk holes. Choose the Counterbore icon

on the Hole dialog.

You can key in dimensions before you select the planar placement face. Key in 16 for the C-Bore Diameter, 6 for the C-Bore Depth, and 9 for the Hole Diameter.

With the Placement Face to you.

selection step active, select the top face of the boss closest

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A hole is made to be a through hole by selecting a plane or face that you want to use to terminate the hole. If a hole is not a through hole, you must specify a depth, and you can specify a drill point angle for the bottom of the hole. With the Thru Face thru face.

selection step active, select the bottom face of the block as the

Apply the Hole dialog.

Next, you will position the hole.

Adding Bosses and Holes to a Model Positioning the Hole You will position the centerline of the hole at the centerline of the boss. The Positioning dialog displays. The system assumes that the centerline of the hole is what will be located. All you need to do is select where it will be located - the target.

Point onto Point Positioning

The Point onto Point method creates a positioning dimension the same as the Parallel option, but with the fixed distance between the two points set to zero. This positioning dimension causes the feature or sketch to move, so that its selected point is on top of the point selected on the target solid.

846 . Choose the Point onto Point icon

on the Positioning dialog.

Select the top circular edge of the boss.

Choose the Arc Center option on the Set Arc Position dialog.

The hole is created.

Adding Bosses and Holes to a Model Creating the Remaining Holes You are returned to the hole dialog for creation of another hole. The parameters of the last hole are displayed so you can create another hole with the same parameters if you wish. Using the same procedure, create the remaining three holes.

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Close all part files.

Adding Blends and Chamfers to a Model In this activity, you will round the vertical edges of the solid body, add a blend to the base of the pad, and add chamfers to the pad.

Adding Blends and Chamfers to a Model Opening the Part File Open the part file fmf1_support_block_4.prt from the fmf1 subdirectory, and start the Modeling application.

848 The part file contains expressions, a block, datum planes, pad, bosses, and holes.

Adding Blends and Chamfers to a Model Creating a Simple Edge Blend

The Edge Blend option lets you create constant or variable blended edge(s) on sheet or solid bodies. Edge Blends are accessed in one of two ways. By selecting the edges you wish to blend, and then choosing MB3 Blend. This allows creation of edge blends without a dialog. Or you have the choice of using the standard dialog. By choosing the Edge Blend icon Edge Blend dialog.

and then selecting the edges to blend, using the

You will round the four vertical edges of the block with a 12 millimeter radius.

Choose the Select General Objects icon General Objects.

, or choose Edit

Selection

Select

The Edge Blend option lets you round edges of a body. Edge blends have a circular cross section. You need to round the four vertical edges of the block with a 12 millimeter radius. When possible, you should blend sets of edges rather than one edge at a time. When many edges are blended at one time, the result is a single blend feature that has many blended edges. However, if you blend several edges together, and later want to change the blend radius at only one edge, it will be more difficult than if you had blended them separately. Select the four vertical edges on the corners of the block.

With the cursor over one of the selected edges, choose MB3

Blend.

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Face Blends, Soft Blends, and Styled Blends are for creating more complex blends and blend cross sections. A preview of the blends is shown on the part. A Radius dynamic input box lets you key in the desired radius.

Key in 12 for the Radius, and press Enter. Choose the OK icon

or use MB2 to complete the blend.

You want a 3 millimeter blend at the bottom of the pad.

850 Using the same procedure, create a 3 millimeter radius blend at the bottom edges of the pad.

Choose the Select General Objects icon on the Selection dialog. Select the two long edges at the bottom of the pad. With the cursor over one of the selected edges, choose MB3 Blend. Enter 3 in the Radius field, and press Enter. Choose the OK icon

or use MB2 to complete the blend.

The shaded model looks like this.

Adding Blends and Chamfers to a Model Adding Chamfers to the Model

You will knock off the sharp edge at the top long edges of the pad. You can choose the Chamfer icon from the Feature Operation toolbar, then select the type of chamfer, and then select the edges to chamfer; or you can select edges and then choose Chamfer from the pop-up menu.

Chamfer Methods

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The Edge Chamfer option creates a flat face to replace an edge of a solid. You can create these chamfer types: Single Offset lets you create a simple chamfer whose offset is the same along both faces. Double Offset lets you create a simple chamfer with different offsets along the faces. Offset Angle lets you create a simple chamfer whose offsets are determined by one offset value and an angle. Freeform Single Offset lets you create a freeform chamfer with a single offset value by which both faces are offset. The intersection of the (theoretical) offset faces determines the chamfer placement. Freeform Double Offset lets you create a freeform chamfer in which different offset values are used to offset the faces. The intersection of the (theoretical) offset faces determines the chamfer placement. In simple methods (Single Offset, Double Offset, and Offset Angle) of creating a chamfer, the offset values are measured along the faces from the edge being chamfered; this defines the start and end values of the new face(s). Simple methods are reliable only when the cross sections of the faces consist of straight lines. For faces that are more complex in shape, the freeform chamfer methods (Freeform Single Offset and Freeform Double Offset) produce more reliable chamfers. In the freeform method, the offset is not measured from the edge; instead, it is the distance that the model's faces are offset. Normals between the original faces and the intersections of the (theoretical) offset faces define the start and end values of the new chamfer face(s). Chamfers on Instances - If you chamfer an edge of a feature which is a member of an instance set, you will have the choice to chamfer all instances, or not. When chamfering all instances, it is best to add the chamfer to the master feature, and not one of the instanced features. This way, if the array parameters are later changed, the chamfer will remain visible in the instance set. You cannot instance a chamfer. If you instance a feature that has a chamfered edge, the instance set will not contain the chamfer.

852 Flip Chamfer Direction - If the chamfer creation method is Double Offset or Offset Angle, once the desired chamfer has been created, you can change its direction by choosing Flip Last Chamfer. The length of the chamfer remains the same when it is flipped.

Choose the Select General Objects icon. You will use a 3 millimeter chamfer on the top two edges of the pad. All edges to be chamfered must be on the same body. Select the two long edges at the top of the pad.

Choose MB3

Chamfer with the cursor over one of the selected edges.

Adding Blends and Chamfers to a Model Completing the Chamfer The Chamfer dialog displays five types of chamfers. You will use a single offset chamfer on the pad feature. The Single Offset chamfer has equal length offsets along both faces. For all simple offsets (Single Offset, Double Offset, and Offset Angle) the offset is measured along the faces from the selected edge.

853 Choose the Single Offset chamfer type. For chamfers created on edges other than linear and circular edges, the system will use the Distance Tolerance, located under Preferences Modeling, to approximate the chamfer. You need to specify the offset value. Key in 3 for the Offset value in the Chamfer dialog. OK the Chamfer dialog. The chamfers are created. The shaded model looks like this.

Close all part files.

Tapering Faces of the Model In this activity, you will add a taper (or a draw) to the model.

The Taper option lets you change the angle of faces relative to a specified direction.

Tapering Faces of the Model Opening the Part File

854 Open the part file fmf1_support_block_5.prt from the fmf1 subdirectory, and start the Modeling application. This part contains expressions, a block, datum planes, pad, bosses, holes, and blends.

Tapering Faces of the Model Starting the Taper

Choose the Taper icon

, or choose Insert

Feature Operation

Taper.

There are many methods and options on the Taper dialog. Refer to the online documentation for complete information on Taper.

You need to choose the Taper type; and in this case, you will select the faces to taper. Use the Faces taper Type

on the Taper dialog.

About Other Taper Options

The Taper option lets you taper features, faces, or bodies, relative to a specified vector. You can create variable tapers, fixed angle tapers, and split-line tapers. Tapers are used frequently in mold designs.

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You can use From Edges to taper along a selected set of edges by a specified angle. This option is particularly useful when the desired edges are not contained in a plane normal to the direction vector (and you do not want to change the edges). From Edges also lets you create tapers with variable angles. Tangent to Faces lets you taper by a given angle, tangent to the faces you select. The angle is used to determine isocline curves which will be used as reference objects. Split-Line Taper lets you create tapered faces from reference edges, such as edges on the front split face.

The first step is to select the faces to taper. You want all the faces of the block parallel to the ZC axis. You can simplify this selection by using a Collector. (The Collector option helps you select objects by limiting the types that are selectable. In addition, if you choose More... a Face Collector dialog displays, letting you select Faces, Region Faces, Tangent Faces, Feature Faces, and Body Faces. As you select faces, and other objects, they will be listed in the list box.) Set the Collector to Tangent Faces.

856 If Taper All Instances is turned on, the taper is applied to all instances in an array. If it is toggled off, the taper is applied only to the instance that you select. Tapering an instance array can slow system performance if the instance array is large. With the Faces to Taper to the ZC axis.

icon active, select any of the outer faces of the block parallel

Choose Preview Collected Faces to see which faces will be tapered.

Choose the Finish Preview option.

Tapering Faces of the Model Selecting the Draw Direction The next selection step is Draw Direction. This is for specifying what direction to measure the taper against. Use MB2 to advance to the Draw Direction

selection step.

You could also choose the Draw Direction icon on the dialog. You want the draw direction to be measured relative to the ZC axis of the Work Coordinate System. This is the default direction, as you can see by the arrow on the graphics screen.

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Tapering Faces of the Model Selecting the Reference Point

The Reference Point selection step

controls the start of the taper.

Use MB2 to advance to the Reference Point selection step. You want the taper to start at the top of the original block. Select an end point of any of the edges on the top of the original block.

The Angle field lets you specify the draw in degrees. Key in 8 for the Angle of the taper, and OK the dialog.

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Close all part files.

859

Creating a Slotted Fixture This lesson provides a series of activities that let you create this model.

In this lesson, you will perform the following: create offset datum planes, and datum axes, create revolved body features, trim a solid with sheet bodies, change object colors, create constant and variable circular edge blends, reorder features, and use make current feature, create an extruded sheet body, create single offset edge chamfers, create counterbored thru holes, and hollow the model.

Creating Reference Features In this activity, you will create three datum planes (one on the top face, and two offset from the bottom face.) You will also create two datum axes at the intersection of two datum planes.

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Creating Reference Features Opening the Part File Open part file fmf1_slotted_fixture_1.prt from the fmf1 subdirectory, and start the Modeling application.

This part has some reference features (datum planes and datum axes), an extrusion (the block), and four sketches (for use in completing the model). Check the layer settings to find the layer categories, and then Close the Layer Settings dialog.

Creating Reference Features Creating a Datum Plane Offset from the Bottom Face

861 You need two datum planes: one at 600 millimeters below the bottom face of the block, and one at 700 millimeters below the block. You also need one at the top face of the block. These are needed for the revolved features and the holes to be created later. You will place the datum planes on layer 61. Make layer 61 the Work Layer. Several datum planes display in the view.

You will add a datum plane that is located on the top face.

Choose the Select General Objects icon General Objects.

, or choose Edit

Selection

Select

Select the top face of the part. With the cursor over the selected face, use MB3 to choose Datum Plane.

The system displays a temporary datum plane with an Offset dynamic input box. You will accept the offset value displayed, which is zero.

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Use MB3

Apply to accept the Offset value of 0, and to create the datum plane.

Now, you can create a datum plane offset 600 mm. from the bottom face of the model. Select the bottom face of the block. Key 600 into the Offset dynamic input box, and press Enter. Use MB3

Apply to create the datum plane.

Fit the view to see the datum plane offset from the bottom face by 600 mm.

Creating Reference Features Creating Another Offset Datum Plane Now, you can create the offset at 700 mm. You should still be in the Datum Plane function, but if you are not, be sure to start it by selecting the icon. Select the bottom face of the block again. Key 700 into the Offset dynamic input box, and press the Enter key. Choose OK

to create the datum plane and dismiss the function.

Fit and Rotate the view to see all datum planes.

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Creating Reference Features Creating Datum Axes

You need to create two datum axes, both on the center datum plane parallel to the YC-ZC plane, with one datum axis located at each of the two datum planes (at 600 mm. and at 700 mm. from the bottom face of the block.)

Choose the Datum Axis icon. Select the center datum plane parallel to the YC-ZC plane of the WCS.

Select the offset datum plane that is 600 millimeters below the bottom of the block. The datum axis temporarily displays.

Use MB3

Apply to create the datum axis.

Choose the same center datum plane that you just used. Select the offset datum plane that is 700 millimeters from the bottom of the block. Choose the OK icon

to create the datum axis and dismiss the function.

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Make layer 1 the Work Layer and make layer 61 Invisible. Close all part files.

Trimming a Solid with a Sheet Body In this activity, you will create a sheet body by revolving an existing sketch.

Then, you will trim the top of the block with the sheet body to create a curved surface on the top face of the solid. Finally, you will create another sheet body and trim the solid so that six slots are created in the body.

Trimming a Solid with a Sheet Body Opening the Part File Open part file fmf1_slotted_fixture_2.prt from the fmf1 subdirectory, and start the Modeling application.

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You will be using a sketch located on 22, and datum planes located on 61. Make layers 61 and 22 Selectable so that you can select the sketch and datums.

Trimming a Solid with a Sheet Body Creating a Revolved Feature You will revolve the cyan sketch (a large arc) about a datum axis located 700 mm. below the bottom of the block. The resulting sheet body needs to be placed on layer 41. Make layer 41 the Work Layer. The Revolved Body icon lets you create a solid or sheet feature by rotating a section string around an axis through a non-zero angle.

Choose the Revolved Body icon

, or choose Insert

Form Feature

Revolve.

The Revolved Body dialog displays section string options: Solid Face, Solid Edge, Curve(s), or Sheet Body. You can use these filters, or select in the view. Select the large cyan arc that lies on the center plane parallel to the YC-ZC plane of the WCS.

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OK the dialog. Now, you must specify a method for the revolution: Axis and Angle, or Trim to Face, or Trim Between Two Faces. The Axis & Angle option lets you specify the axis of revolution, and the start and end angles of the revolution relative to the plane of the selected section string. You will be using a datum axis for the axis of revolution. Choose the Axis & Angle option. The Vector Constructor dialog displays. The default direction vector indicates the direction of revolution that will occur.

Fit the view. With the Vector Constructor dialog displayed, select the datum axis that is 700 millimeters below the block.

The system displays a direction vector at the datum axis. OK the Vector Constructor dialog.

867 The amount of rotation is determined by the start and end angles that you enter. The total number of degrees cannot exceed 360. The plane of the section string is considered to be at zero degrees. Key in -10 as the Start Angle, 10 as the End Angle, and 0 for both offsets.

OK the dialog. The Boolean Operation dialog displays options to Create, Unite, Subtract, or Intersect the feature. Choose Create to create the sheet body on layer 41.

Trimming a Solid with a Sheet Body Setting Layers and Colors You can change object colors for more contrast in your view. Make layer 1 the Work Layer and make layers 22, and 61 Invisible.

Using Edit Object Display, change the color of the sheet body to 73, which is Pale Dull Magenta. Choose Edit Object Display. Select the sheet body and OK the dialog. Choose Color on the Edit Object Display dialog. Choose More, key in 73 in the Number field, press the Enter key, and choose OK until the model updates.

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Trimming a Solid with a Sheet Body Trimming the Model to Create a Curved Face You will use the sheet body you just created to trim off the top of the block to give the top of the solid a curved shape.

The Trim Body function lets you trim a solid body with a sheet body, and at the same time, retain parameters and associativity.

Choose the Trim Body icon

, or choose Insert

Feature Operation

Trim.

The system prompts you to select the target body. Since you will be trimming the solid body, that is the target.You must select the target body even though there is only one possible target displayed. Select the block as the target body, and OK the Trim Body dialog. The Trim Body dialog lists available options for trimming: Define Datum Plane, Define Plane, Define Cylinder, Define Sphere, Define Cone, or Define Torus. You can also select directly in the view. Select the sheet body as the face to do the trimming. The Trim Body displays options to control the direction of trim: Accept Default Direction, or Reverse Default Direction.

Trim Body Options

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Define Datum Plane lets you define a datum plane for the trimming. Define Plane lets you define a plane for the trimming object by using the Plane Subfunction dialog. Define Cylinder lets you define a cylinder for the trimming object, by using a diameter or arc/circle. Define Sphere lets you define a sphere for the trimming object, by using a center and diameter or great circle. Define Cone lets you define a cone for the trimming object, by using two coaxial arcs, diameters and height, or diameter and half angle. Define Torus lets you define a torus as a trimming object and you would have to enter the positive major and minor radius values and define the torus axis. The system is defaulted to the selection of a face or datum plane as the trimming surface, but you could choose from items listed in the dialog that displays.

An arrow displays on the selected sheet body. It should point in the direction of the desired resulting face normal. In this case, it should point upwards.

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If the arrow is pointing upwards, choose the Accept Default Direction option. If it is pointing down, choose the other option. The solid is trimmed.

Make layer 41 Invisible, to hide the sheet body.

Trimming a Solid with a Sheet Body Creating Another Body of Revolution You will create another sheet body and trim the top of the part to produce the slots. You will use another sketch to create the revolved sheet.

This sketch is on layer 23. You also need to select a datum axis on layer 61. Make layers 23 and 61 Selectable.

871 As before, you will create the sheet body on a layer for sheets. Make layer 42 the Work Layer.

Notice that the sketch, displayed in cyan, has many straight line segments at right angles. When this is revolved, it will create a sheet with many slots. You will use this sheet to develop slots in the solid body.

Choose the Revolved Body icon

, or choose Insert

Form Feature

Revolve.

The Revolved Body dialog displays. Select any of the lines that make up the sketch.

OK the Revolved Body dialog. Choose the Axis & Angle option. With the Vector Constructor dialog displayed, select the datum axis that is 600 millimeters below the block. (Fit, Pan, or Zoom as needed.) OK the Vector Constructor dialog. Use -10 for the Start Angle, 10 for the End Angle, and 0 for both offsets. OK the dialog. Choose Create and Cancel the dialog to complete the revolved feature.

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Trimming a Solid with a Sheet Body Changing Layers and Object Display Make layer 1 the Work Layer , and make layers 23 and 61 Invisible. Using Edit

Object Display, change the color of the sheet body to 20.

Choose Edit Object Display. Select the sheet body and OK the dialog. Choose Color on the Edit Object Display. Choose More, key in 20 in the Number field, press the Enter key, and choose OK until the model updates.

Trimming a Solid with a Sheet Body Trimming the Model to Create Slots You are next going to use the sheet body you just created to trim off the top of the block to create the slots.

Choose the Trim Body icon The Trim Body dialog displays.

, or choose Insert

Feature Operation

Trim.

873 Select the solid body as the target body, and OK the dialog. Select the sheet body as the face to do the trimming. A series of arrows display on the selected faces. The vertical arrows should point up. If the arrows are pointing upwards, choose the Accept Default Direction option. If they are pointing down, choose the other option (Reverse Default Direction.) Make layer 42 Invisible.

Close all part files.

Adding Edge Blends to a Model In this activity, you will add a constant radius edge blend on the four outer vertical edges of the model. Then, you will add a variable blend to the edges of the top face of the solid. To make the variable radius, you will use the Reorder function before you create the blend, and the Make Current Feature function after you complete the variable blend.

Adding Edge Blends to a Model Opening the Part File Open the part file fmf1_slotted_fixture_3.prt from the fmf1 subdirectory, and start the Modeling application.

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Adding Edge Blends to a Model Creating the Constant Edge Blends You will create constant edge blends on the four vertical corners of the model.

Choose the Select General Objects icon General Objects.

, or choose Edit

Selection

Select

Select the four vertical edges at the outer corners of the model.

With the cursor over one of the selected edges, press MB3, and choose Blend from the pop-up menu. Key in 13 in the Radius dynamic input box on the graphics screen, and press Enter. The blend preview will update to the new value.

Choose the OK icon

to create the blend and dismiss the function.

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Adding Edge Blends to a Model Reordering Features You need to create a variable radius blend around the top edge of the part, but since you have already created the slots, you need to reorder the features such that the last revolved feature and the associated trim feature are after the blend you just created. An easy way to reorder features is within the Model Navigator window. On Windows systems, double-click on the Model Navigator tab to display the Model Navigator in a separate window, or on UNIX systems, choose the Model Navigator icon to display the window. Notice the order of the features. You need the second revolved and the second trim features to follow the blend feature. Select features REVOLVED(18), and TRIM_BODY(19) in the Model Navigator. (Control and MB1 lets you select multiple features.)

(You might notice that there is no feature numbered 17. This could be because the engineer created and deleted the feature numbered 17.) Hold down MB1 on the selected features, and drag them to BLEND(20).

Release MB1.

876 The features are reordered. The Blend feature is numbered 17, the Revolved is 18, and Trim_Body is 19.

Adding Edge Blends to a Model Changing the Current Feature You still need to get the slots out of the way in order to create the desired variable radius blend around the top edges. You can do this by making the blend the Current Feature. Any feature that follows the blend in timestamp order (in this case, the revolved and trim body features) will be suppressed. Select the BLEND(17) on the Model Navigator. With the cursor on the selected blend (in the navigator), use MB3 to choose Make Current Feature on the pop-up menu.

The revolved and trim features (the slots) are now effectively suppressed, and the next feature created will precede them in time stamp order.

Close the Model Navigator.

Adding Edge Blends to a Model Starting a Variable Radius Blend You want to round the edges around the top of the part, but you want to use a 6 millimeter blend along the long edges, and a 3.5 millimeter blend along the short edges.

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Choose the Edge Blend icon Blend.

, or choose Insert

Feature Operation

Edge

The Edge Blend dialog displays. Turn on Add Tangent Edges. Select any of the edges around the top of the part. You will notice that all edges are selected by the system.

On the Edge Blend dialog, key in 6 for the Default Radius, and press Enter. Notice that the smaller radius is visible in the graphics area. Turn on Allow Variable and Setback. The Edge Blend dialog now displays options for the variable and setback blends.

Adding Edge Blends to a Model Specifying the Variable Radius Now, you need to select the points at which you wish to apply a specific radius. In turn, select each of the end points of the short curved top edges (indicated below), and for each selected point key in a Variable Radius of 3.5, and press Enter. (You may want to Pan, Zoom, and Fit the view as needed.)

878 In turn, select each of the end points of the long curved top edges (indicated below), and for each selected point key in a Variable Radius of 6, and press Enter.

Adding Edge Blends to a Model Completing the Variable Blend OK the Edge Blend dialog. Use the Model Navigator to make the TRIM_BODY(20) feature the Current Feature. The edge blend feature is complete.

Close all part files.

Extruding a Sketch and Trimming Between Faces In this activity, you will extrude the curves in the sketch on layer 24, to create the a cylindrically recessed area on the top of the model. Finally, you will add chamfers to the edges of the cylindrical slot faces.

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Extruding a Sketch and Trimming Between Faces Opening the Part File Open the part file fmf1_slotted_fixture_4.prt from the fmf1 subdirectory, and start the Modeling application.

You are going to extrude a sketch on layer 24, trimming it to the inside faces of the slots on each end. Make layer 24 Selectable. The cyan sketch displays.

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Extruding a Sketch and Trimming Between Faces Starting the Extrusion The Extruded Body option lets you create a solid or sheet body by sweeping generator geometry (curves, solid faces, solid edges, sheet body) in a linear direction for a specified distance.

Choose the Extruded Body icon

, or choose Insert

Form Feature

Extrude.

The Extruded Body dialog displays. You will extrude the sketch. Select either of the two curves that make up the sketch, and OK the Extruded Body dialog. The Trim Between Two Faces/Planes option lets you associate the start and end of the extrusion with specified faces or planes regardless of the section string location. The extrusion will be normal to the plane of the generator geometry. Choose Trim Between Two Faces/Planes. OK the Vector Constructor dialog. This will ensure that the extrusion will be created normal to the plane of the sketch.

Extruding a Sketch and Trimming Between Faces Selecting the Two Faces The Trimming Face dialog displays. You need to extend the trim face, because the objects being extruded are not contained within the selected face. Turn on Extend Trim Face. Select the face indicated below as the first face.

OK the Trimming Face dialog. Select the face indicated below as the second trimming face.

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OK the Trimming Face dialog.

Extruding a Sketch and Trimming Between Faces Completing the Extruded Feature A direction vector (solid font), and an offset vector (dashed font) displays.

You do not need to provide any offsets for this feature. OK the Extruded Body dialog to accept the default values of zero. Choose Subtract to complete the feature. Make layer 24 Invisible.

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Extruding a Sketch and Trimming Between Faces Starting the Chamfer You will create a 2 millimeter single offset chamfer on the ten curved edges of the slots you just created.

Choose the Edge Chamfer icon Chamfer.

, or choose Insert

Feature Operation

The Chamfer dialog displays chamfer types: Single Offset, Double Offset, Offset Angle, Freeform Single Offset, and Freeform Double Offset. Choose Single Offset. Select all ten curved edges of the notches, and OK the dialog.

Extruding a Sketch and Trimming Between Faces Completing the Chamfer Key in 2 for the Offset, and OK the dialog to complete the chamfer feature.

Cancel the dialog. Close all part files.

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Adding Holes and Hollowing a Model In this activity, you will create a counterbored hole at each corner of the model.

After creating the holes, you will offset all the faces (except the bottom face) inward 1.5 millimeters to create a hollow feature.

Adding Holes and Hollowing a Model Opening the Part File Open the part file fmf1_slotted_fixture_5.prt from the fmf1 subdirectory, and start the Modeling application.

884 The two holes you will create near the front of the model will be slightly different from those at the back, because they need to have a deeper C-Bore Depth value. This is because the top of the model is curved. You can rotate the view to check this. Because you will be placing the holes on a datum plane, you need to make the layer with the datum planes selectable. Make layer 61 Selectable.

Adding Holes and Hollowing a Model Creating the First Hole You will be creating the first hole at the front of the model.

Choose the Hole icon

, or choose Insert

Form Feature

Hole.

The Hole dialog displays. Choose the Counterbore icon

on the Hole dialog.

Key in 11 for the C-Bore Diameter, 28 for the C-Bore Depth, and 7 for the Hole Diameter.

With the Placement Face icon active, select the top datum plane (parallel to the XCYC plane of the WCS) as the placement face. The temporary tool solid displays in the center of the datum plane, along with the hole parameters. You will select a through face.

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With the Thru Face icon face.

active, select the bottom face of the block as the through

Choose Apply on the dialog. The hole is still temporarily positioned in the middle of the datum plane. You need to position it at the left front corner of the model. You need to position the arc center of the hole to the arc center of the circular edge of the edge blend. Choose Point onto Point. Select the circular edge at the bottom left front corner of the part, and choose Arc Center on the Set Arc Position dialog. The first hole is created.

Adding Holes and Hollowing a Model Creating a Second Hole You need to create another at the front right corner of the model. Using the same parameters, create another counterbored hole at the right front corner of the model.

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Adding Holes and Hollowing a Model Creating the Last Two Holes You need to create two more counterbored holes at the back of the model. These holes need to have a C-Bore Depth of 20 instead of 28. Otherwise, the parameters will be the same. Using the same placement face, and through face, create the two counterbored holes a the back the part, and key in 11 for the C-Bore Diameter, 20 for the C-Bore Depth, and 7 for the Hole Diameter.

Make layer 61 Invisible, because you will not need to use these datum planes again. The shaded model looks like this.

Adding Holes and Hollowing a Model Creating the Hollow Feature You are now going to offset all the faces (except the bottom face) inward 1.5 millimeters to create a hollow feature.

887 The Hollow option lets you hollow out or create a shell around a single solid body based on specified thickness values.

Choose the Hollow icon

, or choose Insert

Feature Operation

Hollow.

The Hollow dialog displays.

Hollow Types

You can hollow the model in one of three ways: Face, Region, Body. The Face icon lets you create a hollow by collecting pierced and offset faces. You can select faces to pierce, and you can offset the rest of the faces at different thickness values. The Region icon lets you create a hollow based on a collection of faces to be pierced. They are related to a seed face, and are limited by boundary faces. The Body icon lets you create a shell around a single solid body based on a specified thickness value. You can select faces and specify distance values to offset during hollowing.

Choose the Face type

on the Hollow dialog.

You can select one or more faces for removal. When you are selecting face(s) to remove, you may not select faces that are adjacent to a blended edge unless you also select the blend face. With the Pierced Face Pierced Face.

selection step active, select the bottom face of the part as the

888 Positive default thickness values will hollow the solid so that the wall thickness is measured inward from the original outer faces of the solid. Negative values will result in a hollowed solid with a desired thickness around the target solid (original solid), and the target solid will be deleted. If a Hollow operation would cause a self-intersecting condition, the system will not hollow the solid. Key in 1.5 as the Default Thickness, and OK the dialog twice.

Adding Holes and Hollowing a Model Checking the Model You can check the model be rotating and shading it. Shade and Rotate the model to check the hollow feature.

Close all part files.

889

Creating a Slide Fixture This lesson provides a series of activities that let you create this model.

In this lesson, you will perform the following: create curves (lines and offset curves), create extruded bodies, create centered datum planes, create and edit slots, create constant circular edge blends, and create rectangular and general pockets

Creating the Basic Model Shape In this activity, you will create a new millimeter part file, create a straight line, and extrude the line into a solid tapered block. This will be the basic shape of the model to which other features can be added.

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Creating the Basic Model Shape Creating the Part File Start a new part file named slide_fixture using Millimeter units, and start the Modeling application.

Replace the view with the TFR-TRI view.

Creating the Basic Model Shape Creating a Line You need to create a line that will be extruded into the basic shape of the part. In this activity, you will place curves on layer 41, and solids on layer 1. Layer 1 is currently the work layer. Make layer 41 the Work Layer. Create a line along the YC axis, and make it 180 millimeters long starting at 0, 0, 0, and ending at 0, 180, 0. Display the Curve Toolbar Choose the Basic Curves icon

, if it is not displayed. , or choose Insert

Curve

Basic Curves.

Turn String Mode off, and choose the Line icon. Key in the following values in the dialog bar (use the Tab key to move between fields).

Press Enter. Key in the following values in the dialog bar.

Press Enter.

891 Cancel the dialog. Fit the view.

The first line is created along the YC axis.

Creating the Basic Model Shape Setting up Layers and Object Colors Before you create the solid body, you will change layers and change the object color. Make layer 1 the Work Layer. Set the Object Color to number 76, which is light orange red. Choose Preferences Object. Choose the colored rectangle on the Color line.

Choose the More option. Key in 76 in the Number field and press the Enter key. OK the Color dialog. OK the Object Preferences dialog.

Creating the Basic Model Shape Creating the Extrusion You will extrude the green line into a solid block with tapered sides.

Choose the Extruded Body icon

, or choose Insert

Form Feature

Extrude.

892 The Extruded Body dialog lets you select the section string for the extrusion. You can extrude solid faces, solid edges, curves, and sheet bodies. You can simply select from the view or choose to filter your selection using options on the dialog. Select the line in the view, and OK the dialog. Now, the Extruded Body dialog displays extrusion methods. You can extrude using a direction and distance, or with a trim to face/plane, or with a trim between two faces/planes, or extrude through multiple bodies, or with a trim to body option. Choose Direction & Distance. The Vector Constructor dialog displays methods to specify the direction of the extrusion. Choose the ZC Axis icon

, and OK the Vector Constructor dialog.

The Extruded Body dialog now lists parameters that can be specified. Key in the following parameters:

OK the dialog.

Creating the Basic Model Shape Checking the Model The basic shape of the model is visible in the view. Shade the view to check the solid.

893

Change to a Wireframe display Make layer 41 Invisible, so that the curve is not visible. Close all part files.

Adding a Slot to the Model In this activity, you will remove the taper on the extruded body; and create two centered datum planes (reference features.)

Then, you will create a T-Slot that will pass through both the front and back vertical faces of the model, and be positioned in the center of the model. You will use the datum planes to position the slot. Finally you will edit the slot feature, making it a rectangular type of slot.

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Adding a Slot to the Model Opening the Part File Open the part file fmf1_slide_fixture_1.prt from the fmf1 subdirectory, and start the Modeling application. A tapered extrusion displays.

Adding a Slot to the Model Removing the Taper from the Extrusion You will edit the extrusion to change the taper angle to zero.

Choose Select Features

, or choose Edit

Selection

Select Features.

Using MB1, double-click on the solid block. The Edit Parameters dialog displays edit options for the extruded body feature. These include Feature Parameters, Edit Tolerances, Edit Direction, Edit Curve, Edit Defining String, and Replace Defining String. In the view, the curve now displays. Choose the Feature Parameters option. The Edit Parameters dialog displays the parameters that were used to create the feature. The vectors and parameters display also display in the view.

895 Change the Taper Angle to 0, and OK the dialog. OK the Edit Parameters dialog. The extruded body is now displayed with a zero taper.

Adding a Slot to the Model Changing Layers for Datum Planes It is usually desirable to place datum planes on a different layer from the solid model geometry. You will place all datum planes on layer 61. Make layer 61 the Work Layer.

Adding a Slot to the Model Creating the First Centered Datum Plane You are now ready to create the datum planes. Remember, these will be used to position the slot.

Choose the Datum Plane icon

, or choose Insert

Form Feature

Datum Plane.

You can use the datum plane options that display on the graphics area or select faces or edges directly.

Select the front face. The datum plane is temporarily placed so that you can specify an offset in the dynamic input box. Since you will not be using an offset value, you can continue to select objects.

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Select the back face of the part. The datum plane is temporarily centered between the two faces, based on the two selections that you made.

Click MB2 to OK the datum plane. The first centered datum plane is created.

Adding a Slot to the Model Creating the Second Centered Datum Plane You will create another datum plane centered between the right and left vertical faces of the solid.

Choose the Datum Plane icon

, or choose Insert

Form Feature

Select the right vertical face, to specify the first constraint. The datum plane displays with an dynamic input box for the offset value. Select the left vertical face, to specify the second constraint.

Datum Plane.

897 The temporary centered datum plane displays.

Choose OK

to create the datum plane and dismiss the function.

The model now has two centered datum planes.

Now you will return to the layer for solids, and add the slot feature to the model. Make layer 1 the Work Layer.

Adding a Slot to the Model Specifying a Placement Face and Horizontal Reference for a T-Slot You will create a through T-Slot centered on the top of the model.

Choose the Slot icon

, or choose Insert

Form Feature

Slot.

The Slot dialog displays options for slot types (Rectangular, Ball-End, U-Slot, T-Slot, and Dove-Tail), and an option that lets you create through slots (Thru Slot.) Turn on Thru Slot, and choose the T-Slot option. The T-Slot dialog displays placement face options: Solid Face, and Datum Plane. Select the top face of the block as the solid planar placement face.

898 You need to select a horizontal reference. Horizontal Reference options display in a dialog: End Point, Solid Face, Datum Axis, and Datum Plane. In the case of a slot, the horizontal reference defines the X direction and the path of the slot. You can change to a Vertical Reference if you wanted to orient the slot perpendicular to a specific reference. For the horizontal reference, select the longest datum plane.

A vector displays the XC direction and path of the slot.

Adding a Slot to the Model Specifying Through Faces and Parameters for a T-Slot Now the system prompts you to select the faces for the through slot. The dialog that displays lets you specify a solid face or datum plane. Select the front face as the starting thru face.

Select the back face as the ending thru face.

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The dialog now displays the default T-Slot parameters. All values must be positive.

Key in the following parameter values for the slot.

OK the dialog. The temporary tool solid displays.

Adding a Slot to the Model Positioning the T-Slot with Line onto Line The Positioning dialog displays. You will use the two datum planes to position the slot. The Line onto Line positioning icon lets you to create a parallel positioning dimension (constraint), set to zero, between an object of the target solid and an object on the tool solid. Choose Line onto Line. The system prompts you for a target edge for the positioning of the slot. Select the longest datum plane for the target edge.

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The system prompts you for a tool edge. You will use the centerlines of the slot as tool edges for positioning of the slot. Select the longest centerline of the slot.

The Positioning dialog redisplays.

Adding a Slot to the Model Positioning the T-Slot with Point onto Line For the second constraint, you will use Point onto Line positioning method. This time, you will position the slot shortest centerline onto the other datum plane. Choose Point onto Line. For the target edge, select the other datum plane.

901 Select any point on the widthwise centerline of the slot (Zoom in if needed.)

The thru T-Slot is created and positioned.

Cancel the T-Slot dialog.

Adding a Slot to the Model Changing the Slot to a Dove-Tail Type You can explore other slot types before you continue building the model.

Choose Select Features

, or choose Edit

Selection

Select Features.

Using MB1, double-click on the slot. The Edit Parameters dialog displays options for editing the slot feature, and the slot parameters display in the graphics area. You can change the slot size with the Feature Dialog option, place the feature on another face with the Reattach option, or substitute another type of slot with the Change Type option. You will change the current slot to a Dove-Tail slot. Choose Change Type. The dialog now displays slot types.

902 Choose Dove-Tail, and OK the dialog. The Edit Parameters dialog displays parameters that are required for the dove-tail slot type. Dove-Tail Slots require width, depth, and angle parameters. The width and depth values for dove-tail slots must be positive.

Mapping of Slot Feature Parameters

The system maps existing parameter values of slots in the following manner. Rectangular Slot Width Depth Length n/a n/a n/a n/a

Ball End Ball Diameter Depth Length n/a n/a n/a n/a

U-Slot Width Depth Length Corner Radius n/a n/a n/a

T-Slot Bottom Width Bottom Depth Length n/a Top Width Top Depth n/a

Dove-Tail Slot Width Depth Length n/a n/a n/a Angle

Key 15 for the Width, key in 10 for the Depth, and key in 45 for the Angle OK the two dialogs. The slot has changed. A shaded view looks like this.

903

Adding a Slot to the Model Changing to a Rectangular Slot A Rectangular Slot has a flat bottom with rounded ends, if it is not created as a thru slot.

You have decided that the design requires a rectangular slot. Using MB1, double-click on the slot. Choose Change Type. Choose Rectangular, and OK the dialog. Key in the following values.

OK all dialogs.

Other Types of Slots

The Ball-End slot differs from a rectangular slot in that it has a circular bottom.

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A rectangular slot has a flat bottom. The depth of the Ball-End slot must be greater than the ball radius. All values must be positive.

The U-slot can look like a ball-slot or rectangular slot. If the U-slot has a zero radius at the bottom of the slot, it will look like a rectangular slot.

If the U-slot has a radius equal to half the width, it will look like a ball-slot. For U-Slots, you can provide a corner radius to make the bottom of the U-slot rounded.

Close all part files.

Extruding and Blending Edges of a Model In this activity, you will extrude edges to create flanges on either side of the block.

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You will also add blends to round off the corners of the flanges.

Extruding and Blending Edges of a Model Opening the Part File Open the part file fmf1_slide_fixture_2.prt from the fmf1 subdirectory, and start the Modeling application. This part is similar to the one you created in another activity. The rectangular slot has been created on the top of the block, and it was positioned using datum planes.

Extruding and Blending Edges of a Model Creating the First Extrusion Choose Extruded Body

, or choose Insert

Select the lower edge of the right vertical face.

Form Feature

Extrude.

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OK the dialog. Choose Direction & Distance. Select the right vertical face to specify that the extrusion be normal to that face. The direction vector should point away from the solid face.

OK the Vector Constructor dialog. A dashed offset vector, and a solid direction vector display in the view.

If the offset direction arrow (the dashed arrow) is pointing downwards, key in the following values.

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If the offset arrow is pointing upwards, then use 0 for the First Offset, and 20 for the Second Offset. OK the dialog. The dialog displays the Create option, and three Boolean options: Unite, Subtract, and Intersect. You will unite the flange to the model. Choose Unite. The first flange is now part of the model.

Extruding and Blending Edges of a Model Creating the Second Extrusion To make the model symmetrical, you can create another flange on the opposite side. Create the flange on the other side of the part, by extruding the lower edge of the left vertical face. (Remember to watch the vectors, and specify positive or negative values as needed.)

908

Shade and Rotate the view to check the model.

Extruding and Blending Edges of a Model Blending Edges of the Model Return to a Wireframe display mode. Choose Select General Objects. Objects.

, or choose Edit

Selection

Select General

Select the four outermost vertical edges of the model.

Place your cursor over one of the selected edges, click MB3, and choose Blend from the pop-up menu.

909 The dynamic input box displays, so that you can specify the radius for the blends. (Remember, you can also select the Blend Dialog option in the graphics view, if you want to work from the Blend dialog.) Key in 14 in the Radius dynamic input box, and press the Enter key. In the view, click MB2 to OK and complete the blends.

Close all part files.

Adding a Rectangular Pocket In this activity, you will create a 5 millimeter flange around the top face of the part. You will do this with a rectangular pocket. You will use datum planes to position the pocket so that it is always stays in the center of the model.

Adding a Rectangular Pocket Opening the Part File Open the part file fmf1_slide_fixture_3.prt from the fmf1 subdirectory, and start the Modeling application.

910

You will use datum planes that are located on layer 61 to position the rectangular pocket that you will create. Make layer 61 Selectable. Two center datum planes display in the view.

Adding a Rectangular Pocket Creating the Rectangular Pocket You will create a rectangular pocket on the top face of the part. You will make it 10 millimeters smaller than the overall size of the top face of the part. The parent feature in this part is the extruded(0) feature. The dimensions for the top face (of the extruded body feature) are 100 by 180.

Choose the Pocket icon

, or choose Insert

Form Feature

Pocket.

The Pocket dialog lists three types of pockets: Cylindrical, Rectangular, and General. A Rectangular pocket is generally rectangular in shape and can have blended corners and tapered sides. Choose the Rectangular option. As with so many other form features, you must place the pocket feature on a planar placement face or datum plane, so the system prompts you for a selection. For the placement face, select either side of the top face of the extruded(0) feature.

911 You must select a horizontal reference. The reference that you select will determine the path (X-length orientation) for the pocket. The Horizontal Reference dialog displays reference options.

Since you want the length of the pocket along the YC axis, you will use the longest datum plane for a horizontal reference. For a horizontal reference, select the datum plane that is parallel to the YC-ZC plane of the WCS. The direction vector represents the length of the pocket. Default parameters for the rectangular pocket display in the dialog. The lengths (X, Y, Z) define the size of the pocket on the planar face. The X Length is applied along the horizontal reference that you specify. The corner radius is the radius between the vertical sides of the pocket. The corner radius must be equal to or greater than the floor radius after any taper has been applied. A zero radius results in sharp corners. The floor radius is the radius between the bottom face and side faces of the pocket. The taper angle is the angle at which the four walls of the pocket incline inward toward the bottom. A value of zero results in vertical walls.All values must be positive. Key in the following parameter values.

OK the dialog.

912

Adding a Rectangular Pocket Positioning the Pocket The pocket tool body temporarily displays in the view with the WCS temporarily located at the center of the tool body. Notice that dashed centerlines are displayed for rectangular pockets. To center the pocket, you will align the datum planes with the centerlines of the pocket. Choose Line onto Line

on the Positioning dialog.

Select the longest datum plane as the target edge. Select the longest centerline of the pocket as the tool edge. Now you can align the other pair (centerline and datum plane). Choose Point onto Line

for the second positioning method.

Select the other datum plane as the target edge, and then select shortest centerline of the pocket.

Cancel the dialog. Make layer 61 Invisible and Shade the view.

Close all part files.

913

Adding a General Pocket to a Model In this activity, you will create raised edges on the lower two extensions on this model. To create these edges, you will use the general pocket function. The creation of a pocket requires outline curves, which you will create by offsetting curves from solid edges. The finished model will look like this.

Adding a General Pocket to a Model Opening the Part File Open the part file fmf1_slide_fixture_4.prt from the fmf1 subdirectory, and start the Modeling application. A rectangular pocket is located on the top of the model.

You will place curves for the general pocket on layer 42. Change the Work Layer to 42. To easily distinguish curves from the solid body, you can specify a different color for curve objects. Set the Object Color Preference to number 7 (white). Choose Preferences Object. Choose the colored rectangle on the Color line.

914 Choose the More option. Key 7 into the Number field and press Enter. OK the Color dialog. OK the Object Preferences dialog.

Adding a General Pocket to a Model Creating Offset Curves Choose the Offset Curve icon

, or choose Insert

Curve Operation

Offset.

The Offset Curve dialog displays string selection methods. You will offset curves from existing edges of a face on the solid body. Select the top face of the near flange to select all edges of the face of the near flange.

OK the dialog. The Offset Curve dialog displays many options that let you specify parameters, tolerance, and much more. Offset Curves are also covered in the Curves course. (Refer to the online documentation for complete information about offset curves.) Make sure the offset direction arrow is pointing inward. If it is not, choose the Reverse Direction option on the Offset Curve dialog. Make sure the Associative Output switch is turned on. Key in a Distance of 3, and OK the dialog. The first set of offset curves is complete.

915 Using the same function, create another offset curve feature on the other flange. Use the same values. Refresh the view.

Adding a General Pocket to a Model Starting the General Pocket Now that the curves have been created, you can add the general pocket. General pockets provide you with many more options than rectangular pockets. You will create the general pockets on the solids layer, which is 1. Change the Work Layer to layer 1. Choose the Pocket icon

, or choose Insert

Form Feature

Pocket.

The Pocket dialog displays three creation methods: Cylindrical, Rectangular, and General. The General pocket option lets you create pockets that have user-specified shapes. Thus, you have greater design flexibility than you have with the cylindrical or rectangular pockets. The shape of a general pocket is controlled by outlines (curves/edges), by specified placement and/or floor faces, and by specified tapers and/or blend radii. Choose the General pocket type. The General Pocket dialog displays parameters for creating the feature. Notice the large number of options. Near the bottom of the General Pocket dialog, the Attach Pocket option is toggled on by default, so the pocket will be subtracted from the model. If it were toggled off, a separate solid body would be created for the pocket.

916

Adding a General Pocket to a Model Specifying a Placement Face for the General Pocket The Placement Face selection step is active. The placement face is one or more selected faces, or a single plane or datum plane. The top of the pocket follows the contours of the placement face. The placement outline curves are projected onto the placement face, if necessary. You need to select the placement faces for the pocket. General pockets can be placed on any face, not just planar faces. With the Placement Face the placement face.

selection step active, select the top face of the near flange as

The vector displays the direction in which the pocket will be created.

Click MB2 to advance to the next selection step.

Adding a General Pocket to a Model Specifying the Placement Outline The Placement Outline selection step lets you select the objects that define the shape of the pocket on the placement face. With the Placement Outline selection step active, select all the curves that make up the offset curve feature you just created as the placement outline. (Remember, you can filter for curves and drag a rectangle around the curves on the face.) The system displays a vector. Again, click MB2 to advance to the next selection step.

917 The Floor Face selection step lets you provide an offset, or translation for the floor. With the Floor Face for From Placement.

selection step active, choose Offset and key in a distance of 2.0

Adding a General Pocket to a Model Specifying the Floor Outline and Taper The Floor Outline selection step lets you define the outline to be used to define the shape of the floor. Choose the Floor Outline

selection step icon on the dialog.

You can specify a value for the taper from the floor outline to be used in generating the placement outline. You can make the taper angle Constant, Law Controlled (where you define a single law relative to the floor outline), or By Outline (where you define a law for each curve in the floor outline). The taper angle can be measured relative to the floor's face normals, a vector, or a datum axis. If you specify a vector, an arrow is displayed that shows this vector direction whenever this step is active. If you select a datum axis, the Relative to: option automatically changes to Selected Datum Axis. However, if you select any curves to define the placement outline, any selected datum axis is automatically unselected. Once curves are selected, you can no longer select any datum axis unless you first deselect all the curves. Key in 8 as the Taper Angle, choose Constant, and use Relative to: Face Normals.

Leave the Placement Radius, Floor Radius, and Corner Radius set to 0 (zero). OK the dialog.

918 The first general pocket is complete.

Adding a General Pocket to a Model Checking the First General Pocket You should check the general pocket before you continue to create the second one. Shade the model.

Next, you will continue to place another pocket on the other flange. Return to a Wireframe display.

Adding a General Pocket to a Model Creating the Second General Pocket You will create the other pocket on the other flange. Repeat the process to create a general pocket on the other flange. Make layer 42 Invisible.

Close all part files.

919

Using Sketches to Build Models This lesson provides a series of activities that let you create this model.

In this lesson, you will perform the following: create extruded bodies from sketches, create revolved bodies from sketches, trim a solid with sheet bodies, intersect solid bodies, create, rename, edit, and use expressions, create tangent, and angled datum planes, create simple through holes, and create internal and external grooves.

Creating a Hex Nut from Sketches In this activity, you will create a hex nut from two sketches.

Creating a Hex Nut from Sketches Opening the Part File

920 Open part file fmf1_nut_bolt_1.prt, and start the Modeling application.

This file contains the two sketches.

Creating a Hex Nut from Sketches Starting an Extruded Body You can extrude the hexagon sketch to create the basic shape of the nut.

Choose the Extruded Body icon

or Insert

Form Feature

Extrude.

The Extruded Body dialog provides options for the section string selection. The section string that you will use is the hexagonal sketch that includes the circle. Select any curve on the hexagon sketch to select the total sketch, and then OK the dialog.

The Extruded Body dialog lists extrusion methods. You will extrude the sketch in the ZC direction.

921

Choose Direction & Distance. A direction vector displays, and the Vector Constructor dialog displays to let you specify the direction for the extrusion. The default direction is what you want, so you do not need to make any changes. Choose OK on the Vector Constructor dialog to accept the default direction.

Creating a Hex Nut from Sketches Completing the Extruded Body The Extruded Body dialog now lists parameter fields for the extrusion. Use a Start Distance of 0, and key in 22.6 for the End Distance (all other values should be zero), and choose OK. The basic shape of the nut has been created.

Creating a Hex Nut from Sketches Starting the Revolved Body To create the chamfers on the top face of the nut a number of functions can be used, but in this activity, you will revolve the second sketch, and intersect the two solids to create the final model.

922

Choose the Revolved Body icon

, or choose Insert

Form Feature

Revolve.

The Revolved Body dialog displays section string selection options. Select any curve on the other sketch, and OK the dialog. The total sketch highlights. The Revolved Body dialog now displays methods of revolving the section string. You will be revolving the sketch about an axis, so Axis & Angle is the option that you will use. Choose Axis & Angle. The Vector Constructor dialog displays to let you specify the axis of revolution. You will use the sketch curve located on the ZC axis, so you can select the curve in the view.

Select the longer vertical line of the same sketch as the Axis of Rotation. A direction vector displays along the line.

923

OK the Vector Constructor dialog.

Creating a Hex Nut from Sketches Completing the Revolved Body The Revolved Body dialog displays parameters for the revolved body. Make sure that the Start Angle is at 0, and the End Angle is at 360, and then OK the dialog. The Boolean Operation dialog displays. You will create the solid body and perform the intersect later, although you could do it now. Choose Create. The revolved solid is created.

Cancel the Revolved Body dialog.

Creating a Hex Nut from Sketches Intersecting Two Solids

924 The next step is to create an intersecting solid with the two solids that you have just created.

About Intersect

An Intersect is the result of where one solid body intersects another.

The figure below has been partially shaded for additional clarity.

An intersection occurs where the solids share some of the same area in model space. This is shown in red in the figure below.

925

When you intersect these two bodies, the result is one solid body, like this.

Choose the Intersect icon

, or choose Insert

Feature Operation

Intersect.

The Intersect dialog displays. The dialog is very similar to the other Boolean operations dialogs for Subtract and Unite. With the Target Body

With the Tool Body

selection step active, select the hexagonal solid body.

selection step active, select the revolved solid.

926

Since you will not need to use the other options on the dialog, choose OK to complete the intersection. The model is complete.

Close all part files.

Creating a Hex Bolt from a Sketch In this activity, you will use portions of a sketch to create parts of a solid hex bolt.

Creating a Hex Bolt from a Sketch Opening the Part File Open part file fmf1_nut_bolt_1.prt from the fmf1 subdirectory, and start the Modeling

927 application.

This file contains two sketches.

Creating a Hex Bolt from a Sketch Starting the Bolt Head You will create the head of the bolt by extruding the hexagonal portion of the sketch.

Choose the Extruded Body icon

, or choose Insert

Form Feature

Extrude.

The Extruded Body dialog lists section string options. To select a portion of a sketch, you could use Curve. If you just select any line in a sketch, the system will select the entire sketch by default. Choose Curve on the Extruded Body dialog. Select the six sides of the hexagon sketch, and OK the dialog.

Choose OK to complete the section string selection. The Extruded Body dialog displays five methods of extruding objects. Choose Direction & Distance.

928 The Vector Constructor dialog displays methods to specify the direction of the extruded body. The default direction vector displays along ZC. Choose OK accept the plane normal, which is what you want; because, then the extrusion will always be normal to the sketch plane.

Creating a Hex Bolt from a Sketch Completing the Hex Shape of the Bolt Head The system displays an extrusion direction vector and an offset vector. Use a Start Distance of 0. Key in 22.6 for the End Distance, and OK the dialog.

The head of the bolt is partially complete. Cancel the dialog.

Creating a Hex Bolt from a Sketch Adding a Chamfer to the Bolt Head Choose the Revolved Body icon

, or choose Insert

Form Feature

Revolve.

Select a curve on the other sketch, the total sketch will highlight, and then choose OK.

929 The Revolved Body dialog lists options to revolve the sketch. Choose Axis & Angle. The Vector Constructor dialog displays. You need to specify the axis of revolution. Select the longer vertical line on the same sketch to indicate that it will be the Axis of Rotation.

A direction vector displays along the ZC axis in the view. OK the Vector Constructor dialog. The Revolved Body dialog displays parameter fields. Use a Start Angle of 0, and an End Angle of 360. Then OK the Revolved Body dialog. The dialog of Boolean Operations displays four options: Create, Unite, Subtract, and Intersect. Choose Intersect option from the Boolean Operation dialog. The chamfer on the top of the hex bolt head is complete.

930

Creating a Hex Bolt from a Sketch Extruding the Shaft for the Bolt You are now going to create the shaft portion of the bolt using a circle on the sketch. Change your display from shaded to Wireframe.

Choose the Extruded Body icon

, or choose Insert

Form Feature

The dialog lists section string selection options. Choose Curve, and select the circle on the sketch, and then choose OK twice.

Creating a Hex Bolt from a Sketch Specifying Direction and Values for the Shaft The dialog lists extrusion methods. You will extrude in a -ZC direction. Choose Direction & Distance.

Extrude.

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You need the direction vector pointing in a negative direction, and the vector currently points in the positive direction. The Vector Constructor dialog provides an option to reverse the direction vector, Cycle Vector Direction. Choose Cycle Vector Direction to flip the extrusion direction.

OK the Vector Constructor dialog. The direction and offset vectors are displayed in the view. Use a value of 0 for the Start Distance, key in 60 for the End Distance, and then OK the dialog.

Creating a Hex Bolt from a Sketch Completing the Bolt The Boolean Operations dialog displays options. You will Unite the shaft to the head of the bolt.

About Unite

The solid block (target body) will unite to the solid ball (tool body).

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The result of using Unite is that one solid body will contain the total volume of both solid bodies.

Choose Unite on the Boolean Operation dialog. Change your display from wireframe to Shaded.

Close all part files.

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Using Expressions In this activity, you will use expressions to control the nut, so that when one value changes, the entire model updates.

Using Expressions Opening the Part File Open the part file fmf1_nut_mm_exp_1.prt from the fmf1 subdirectory, and start the Modeling application. The two sketches display in the view. The datum planes, on which these sketches were created, are blanked. A solid body (the nut) is located on layer 3.

Using Expressions Starting the Expressions Function You will look at the expressions that currently exist in the part. Choose Tools

Expression.

The Expressions dialog lists these expressions. By using expressions, the two sketches can be controlled and fully associated to just one value, the shaft diameter. K=22.6 is the value that was be used for the extrusion height.

934 d=36 is the shaft diameter. k1=20.34 is the Wrenching Height. p1=60 controls the 60 degree angle for the hexagon. p10=25 is the nominal angle for the chamfer. p18=67.5 is the Width Across Corners.

Using Expressions Renaming Expressions You will rename expression using relevant ANSI standards. Some of the names have already been renamed (K, k1, and d). You need to rename p1, p10, and p18. It is important that you name the expressions with meaningful names for future use. This part has been modeled to the standard in the Machinery's Hand Book ANSI B18.2.3.6m-1979 table 7.

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You will not need the S value. K=22.6 the value that will be used for the extrusion height of the head. d is the shaft diameter k1 is the Wrenching Height of the head. c_ang is the angle for the chamfer (15-25 deg.). E is the Width Across Corners of the head First, you will change p18 to E. Choose p18 from the expression list, and choose the Rename icon at the bottom of the Expressions dialog. The Rename dialog displays the p18 name. Key in E, and OK the Rename dialog. As you can see name p18 has changed to E. Rename the p10 expression to c_ang. Rename the p1 expression to hex_ang. When you are finished, the expressions will look like this.

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Using Expressions Changing the Value of an Expression You will relate all expressions to the diameter of the shaft. Make Layer 3 selectable to see the solid body. The expression value of the E (Width Across Corners) should be 1.875 times the diameter of the shaft. Choose E to display the expression in the editing field.

Change the value (67.5) to 1.875*d, and press the Enter key. The expression will update to the new value in the expression list.

The expression value of the K (height of the head) should be 0.628 times the diameter of the shaft. Choose K, and change the value from 22.6 to d*0.628, and press the Enter key. The expression will update to the new value in the expression list.

The expression value of the k1 (Wrenching Height) should be 90% of the head height. Choose k1, and change its value to K*0.90, and press the Enter key. Updated expressions will look like this.

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Choose OK on the expression dialog to accept all your changes.

Using Expressions Modifying Your Model You can relate model parameters to the diameter of the shaft. This will allow you to change only one value, and the part will update to the proper size and shape as required for that diameter. Choose Tools

Expression, and choose the d=36 expression.

You will make the hole diameter much smaller and update the model. Change the value from 36 to 10, and press the Enter key. Then OK the dialog to complete the changes, and close the dialog. The nut is now smaller, to match the 10 mm. hole diameter requirement.

Close the part file.

Adding Holes and Grooves to a Cylindrical Body In this activity, you will add datum planes, simple thru holes, and grooves to a hydraulic fitting. You will use expressions to control the location of the holes that you add.

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Adding Holes and Grooves to a Cylindrical Body Opening the Part File Open the part file fmf1_hyd_fitting_1.prt from the fmf1 subdirectory, and start the Modeling application. The model displays.

Adding Holes and Grooves to a Cylindrical Body Changing Layer Settings You need to make layer 2 selectable, because it contains datum planes that you will use. Make layer 2 Selectable. The datum plane and two datum axes display.

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Adding Holes and Grooves to a Cylindrical Body Creating a Datum Plane Tangent to a Cylindrical Face For this type of hydraulic fitting, a hole is required that pierces a cylindrical face to allow the fluid to flow from the outside to the inside of the fitting. To create a hole through a cylinder, you need to place the hole on a datum plane that is tangent to the cylinder. This Datum will be created tangent to the cylinder and parallel to the center datum.

Choose the Datum Plane icon

, or choose Insert

Form Feature

Datum Plane.

Select the Datum Plane then select the cylindrical face.

After you make your initial selections, a temporary datum plane is located tangent to the cylindrical face. It may not be located exactly where you want it, so you can use Alternate Solution to relocate the datum plane.

Choose the Alternate Solution icon (several times) if needed, to place the temporary datum plane parallel to the datum plane that you selected and tangent to the outside cylindrical face.

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Choose OK. The tangent datum plane should look like this.

Adding Holes and Grooves to a Cylindrical Body Starting the Hole You will create a hole on the tangent datum plane.

Choose the Hole icon

, or choose Insert

Form Feature

Hole.

The Hole dialog displays. For the placement face, you will use the tangent datum plane. Use the Simple

hole feature.

You do not need to specify the depth or tip angle, because you will be creating a through hole.

941 Key in 15 for the Diameter of the hole. With the Placement Face

selection step active, select the tangent datum plane.

The tool solid displays temporarily.

Now, you need to specify the through face. With the Thru Face selection step active, select the inside cylindrical face (the hole in the center of the shaft) for the through face, and OK the Hole dialog. The Positioning dialog displays.

Adding Holes and Grooves to a Cylindrical Body Positioning the Hole You will position this hole with the perpendicular, and point onto line options. Use the Perpendicular the head of the bolt.

positioning method, and select the Datum Axis at the base of

The datum axis to select is displayed in red.

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Once the Datum axis has been selected, key in 30 then press the Enter key. The Positioning dialog should still be displayed. Choose Point onto Line

icon, and select the other center datum axis.

The datum axis to select is displayed in red.

Once the datum axis has been selected, then OK the Positioning dialog to complete the first hole.

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Adding Holes and Grooves to a Cylindrical Body Creating an Angled Datum Next, you will create a hole for a safety wire. The safety wire will prevent the fitting from unscrewing during operation. You will create the hole at an angle to an existing solid face. To do this, you will first create an angled datum plane.

Choose the Datum Plane icon

, or choose Insert

Form Feature

Datum Plane.

Select a flat face of the bolt head. The face is highlighted in red and the arrow indicates where to select the edge. Select one of the adjacent vertical edges of the bolt. Do not select the edge at the midpoint or end point. Remember to Zoom, if needed. Remember, you can use the QuickPick cursor.

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The system will display an Angle field, so that you can specify the angle you desire.

Key -60 into the dynamic input box. Choose OK. The angled datum plane is created. You can now use it to place the hole through the head of the solid body.

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Adding Holes and Grooves to a Cylindrical Body Creating a Hole on an Angled Datum Plane

Choose the Hole icon

, or choose Insert

Form Feature

Hole.

The Hole dialog displays. Key in 3 for the Diameter. You will create a simple thru hole, placing it on the angled datum plane that you just created. With the Placement Face just created.

selection step active, select the angled datum plane that was

Select the opposite face (not the first face a drill would pierce but the last face a drill would pierce) for the through face then OK the Hole dialog.

When the Positioning dialog appears, choose the Perpendicular method, and select the edge on which the datum plane would pivot. The edge to select is highlighted in red.

K is an expression that already exists in this part file. K controls the total height of the head of the bolt. You will control the location of the hole with an expression based on the K.

946 Key in K/4 for the distance from the edge. Press the Enter key. Use the Perpendicular option, and select the edge at the base of the head. The edge to select is highlighted in red.

Key in K/2 for the distance from the edge, and then OK the dialog. The hole is complete.

To change the angle of the hole, all you need to do is change the angle of the datum plane.

Adding Holes and Grooves to a Cylindrical Body Adding an External Rectangular Groove Unlike many other form features (holes, slots, etc.), you place grooves on cylindrical faces -- not planar faces. Grooves can be created as internal features (e.g., inside a hole) or as external features. You will add an external groove to the outside of the bolt.

947

Choose the Groove icon

, or choose Insert

Form Feature

Groove.

The Groove dialog displays three types of grooves that you can create: Rectangular, Ball End, or a U Groove.

Groove Types

You can create three types of internal or external grooves: rectangular, ball end, and u groove.

The U groove has radii in the bottom corners of the groove. Unlike the U groove, the Rectangular groove has sharp corners all around. The Ball End groove is different than the U groove and the rectangular groove, because it always has a full radius at the bottom of the groove. The ball diameter is the width of the groove.

You will add a rectangular groove to the exterior of the shaft. Choose the Rectangular type. Select the outside cylindrical face of the shaft. The Rectangular Groove dialog displays parameters for Groove Diameter and Width. You will relate the groove diameter to the diameter of the shaft. (The groove diameter is the inner diameter of an external groove, or the outer diameter of an internal groove. For an external groove, like the one you are creating, the diameter must be smaller than the diameter of the selected cylinder.)

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The expression named d already exists in the part file. The d expression controls the diameter of the shaft. Currently d = 36 mm. You want a groove depth of 2.5 mm., so the diameter of the groove needs to be 31 mm. You want the width of the groove to be 5 mm. (The width is measured along the axis of the selected face.) Key in d-5 for the diameter, and key 5 for the width of the groove. Choose OK. The Position Groove dialog displays. Since you are working in a solid display, you can change to a wireframe view. This will aid in the selection of the edges required for positioning. Change your display from shaded to Wireframe. The green dashed groove line is a temporary centerline display that is used for positioning the groove to its center. A groove can be positioned from an edge by selecting the proper edge of the disk. The tool that creates the groove appears as a large disk. The diameter (hole in center of the disk) is the diameter that you entered earlier: d-5.

The system prompts you to select a target edge or accept the initial position. For the target edge, select the edge where the shaft, and the head of the bolt come together. The edge to select is highlighted in red.

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Now, you are prompted to select tool edge. For the tool edge, select the green dashed centerline. The Create Expression dialog lets you specify the expression for the distance between the selected target and tool edges. K is an expression that exists in the part file, and it controls the total height of the head of the bolt. Key in K/2 as the distance from the base of the head to the center of the groove then OK the dialog. Change your display from wireframe to Shaded. The external groove displays just below the head of the bolt.

Adding Holes and Grooves to a Cylindrical Body Adding an Internal U Groove Now, you will add an internal U-Groove.

950 Choose the Back option on the Rectangular Groove dialog. Choose U Groove on the Groove dialog. Select the inside cylindrical face of the bolt shaft. The U Groove dialog displays parameters for Groove Diameter, Width, and Corner Radius. Currently the hole in the bolt shaft is 16 mm., so 21 mm. will produce a groove 5 mm. larger in diameter, this translates to a grove that is 2.5 mm. deep. The width or thickness of the groove will be 5.0 mm. wide an its corner radius will be 1.0 mm. (For internal grooves, the groove diameter is the outer diameter of the internal groove. For internal grooves, the groove diameter must be larger than the diameter of the selected face.) Key in 21 for the Groove Diameter, key in 5 for the Width, key in 1 for the Corner Radius, and OK the U Groove dialog. The Position Groove dialog displays. Change your display from shaded to Wireframe. The tool solid displays as a disk.

You need to select a target edge or accept the initial position. For the target edge, select the edge at the end of the shaft. The edge to select is highlighted in red.

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The green dashed line is a temporary display that can be used for positioning the groove to its center. Now, you need to select a tool edge. As before, you will use the centerline of the groove as the tool edge. For the tool edge, select the green dashed groove centerline. The Create Expression dialog displays. You will relate the location of the groove to K, which is an expression that controls the total height of the head of the bolt. Key in K/4 for the distance from the end of the shaft to the center of the groove. Then OK the dialog. Change your display from wireframe to Shaded.

Close all part files.

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Creating a Pulley This lesson provides a series of activities that let you create this model.

This is an example of a positive belt pulley used on a DOHC engine. It can be used in many other belt driven applications such as pumps and power take-off equipment where no slippage of the belt is allowed. In this lesson, you will perform the following: create a cylinder, create datum planes through the cylinder axis, tangent to the cylindrical face, and centered between two parallel faces, create a simple flat bottom hole, and simple thru holes, create a boss, create a thru slot, and create circular instance arrays.

Creating the Basic Shape of the Pulley In this activity, you will create a cylinder for the basic shape of a pulley, and then add datum planes, a recess, hub, and make the model symmetrical.

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Creating the Basic Shape of the Pulley Opening the Part File Open part file fmf1_pulley_1.prt from the fmf1 subdirectory, and start the Modeling application. The part has been set up with layers named for datums and solids. It is a good practice to create category names for layers, and to place appropriate geometry on named layers. Check the layers that are allocated to named categories. (Hint: Format

Layer Settings.)

Creating the Basic Shape of the Pulley Creating a Cylinder The part can be started with a simple cylinder.

Choose the Cylinder icon

, or choose Insert

Form Feature

Cylinder.

The Cylinder dialog displays two methods of creating cylinders: the Diameter, Height method, and the Height, Arc method. Choose Diameter, Height as the creation method. The Vector Constructor dialog displays, so that you can specify the direction for the cylinder. You will be positioning it along the ZC axis. Choose the ZC Axis icon Constructor dialog.

as the direction for the cylinder, and OK the Vector

The direction vector displays in the view. Default dimensions display in the Cylinder dialog.

954 Key in a Diameter of 120 , and a Height of 30, and OK the dialog. The Point Constructor dialog displays, so that you can specify the origin of the cylinder. Set the base point (origin) to XC of 0 , YC of 0, ZC of 0, and OK the Point Constructor dialog. (Remember, you can use the Reset option.) Cancel the Vector Constructor dialog.

Creating the Basic Shape of the Pulley Creating a Datum Plane Through the Axis of a Cylinder Now, you will create the datum planes that you will need for the remainder of this activity.

Datum Planes Needed for this Activity

Datum planes can be created as needed, but it is good practice to plan ahead and create all the datums first. Four datum planes are required to model this part. (It is better to create only the minimum number of reference features needed to create your geometry.) Two datum planes will be used to position the simple thru hole.

955 The slot will be placed on the datum plane that is tangent to the cylinder.

Two datum planes will be used to position the thru slot.

The largest horizontal datums will be used to mirror features.

The first datum plane that you will create will be used to position a hole on the model. Change the current display to Wireframe.

956 Since you want the datum plane on layer 61, make layer 61 the Work Layer. Choose the Datum Plane icon

, or choose Insert

Form Feature

Datum Plane.

To help you select the axis, a temporary axis displays when you move your cursor over the axis of the cylinder. Select the axis of the cylindrical face.

A temporary datum plane displays.

In the graphics area, press MB3, and choose Apply to complete the datum plane.

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Creating the Basic Shape of the Pulley Creating a Datum Plane Perpendicular to Another

You need to create another datum plane that passes through the axis of the cylinder and is perpendicular to the current datum plane. Select the axis of the cylinder, again.

Select the datum plane. A new angle value can be keyed in at this point, if the value is not 90 degrees, or you can select (MB1) and dynamically drag the ball to the desired angle.

With the angle at 90 degrees, press MB3, and choose Apply. Remember, these datum planes will be used to position a hole.

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Creating the Basic Shape of the Pulley Creating a Datum Plane Tangent to a Cylinder

Now you will create a datum plane tangent to the cylinder. It will be used to locate the slot on the edge of the cylinder.

If necessary, choose the Datum Plane icon Datum Plane.

, or choose Insert

Form Feature

Select the last datum plane that you created. The temporary vector displays, and an offset dynamic input box is available, if you need to specify an offset.

Select the axis of the cylindrical face.

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The Alternate Solution icon will cycle through the different locations for the datum plane.

Choose Alternate Solution

Apply (MB3

until the datum plane is in the correct position.

Apply) the datum plane.

The datum plane is complete.

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Creating the Basic Shape of the Pulley Creating a Datum Plane Centered between Two Parallel Faces The next datum plane will be used to position a slot, and to mirror features. Select the top flat face of the cylinder. When the top flat face of the cylinder is selected, a display of a datum plane will appear, this is not the datum you need. The bottom flat face of the cylinder must be selected for a centered datum plane to appear. Select the bottom flat face of the cylinder. Then OK

the datum plane.

You have completed all datum planes that are needed for this model.

Creating the Basic Shape of the Pulley Creating a Recess in the Cylinder Next, you need to create a recessed area in the center of the cylinder. This could be done with the hole feature, or the extruded body feature, among other methods. You will use the hole feature for this activity. The relief has to be deep enough for weight reduction but not so deep as to remove strength causing failure during operation. In this case, a 13 mm. depth will work. Make layer 1 the Work Layer. Choose the Hole icon

, or choose Insert

The Hole dialog displays. Choose the Simple hole type.

Form Feature

Hole.

961 Key in 105 for the Diameter, and 13 for the Depth, and 0 for the Tip Angle. With the Placement Face icon the dialog.

active, select the top face of the cylinder, and then OK

The hole is temporarily displayed on the model, but you need to position the hole.

Creating the Basic Shape of the Pulley Positioning the Hole The Positioning dialog displays. You will use Point onto Point. Choose the Point onto Point icon to locate the center of the hole.

, and select an outside circular edge of the cylinder

On the Select Arc Position dialog, choose Arc Center. The relief is created. If the model is shaded, it looks like this. (Datum planes have been removed from this image for clarity.)

Creating the Basic Shape of the Pulley Creating a Hub on the Pulley Next, you will create a boss to form a hub at the center of the relief. To create the proper size of hub, you need to know the size of the shaft used with this pulley. For creation purposes the diameter of the shaft will be 15 millimeters. This means that the hole in the hub must be at least 15 millimeters, and the hub must be at least twice that diameter (30 mm.) The relief and the boss can be mirrored to create a symmetrical body.

Choose the Boss icon

, or choose Insert

Form Feature

Boss.

962 The Boss dialog displays default values. You must place a boss on a planar placement face or datum plane. Select the bottom face of the hole that was just created. Key in the value of 30 for the Diameter, and 12 for the Height, and 0 for the Taper Angle, and then OK the dialog. The Positioning dialog displays. You will align the center points of the boss and cylinder. Choose Point onto Point

, and select an outside edge of the cylinder.

On the Select Arc Position dialog, choose Arc Center. The hub is now placed at the center of the relief of the pulley. A shaded view looks like this (without datum planes).

Creating the Basic Shape of the Pulley Mirroring the Hole and Boss One simple way to exactly duplicate the boss and hole, and make the model symmetrical is to mirror the two features about the center datum plane. That will eliminate the need to create another boss and hole. Also, if you change the parameters of the boss or hole, the mirrored features will update, keeping the model symmetrical.

Choose the Instance Feature icon Instance.

, or choose Insert

Feature Operation

The Instance dialog displays options for Rectangular Array, Circular Array, Mirror Body, Mirror Feature, and Pattern Face. Refer to the online documentation for details on all options. The Mirror Feature option lets you create symmetrical models by mirroring selected features through a datum plane or planar face. Choose Mirror Feature on the Instance dialog.

963 The Mirror Feature dialog lists features in this part. You now need to select the features to mirror.

Creating the Basic Shape of the Pulley Selecting Features to Mirror

The Feature to Mirror

selection step is active, so you can select features to mirror.

In the dialog, choose SIMPLE_HOLE, and drag the cursor down through the BOSS (to highlight both).

Mirror Feature Dialog Options

Add Dependencies — When ON, specifies that feature dependencies for those features you add to the Features in Mirror listing be included in the output MIRROR_SET feature. This is

964 only effective when you are adding features to the Features in Mirror list. Turning this option on after you have finished adding features to the Features in Mirror list has no effect. All in Body — When ON, specifies that all features in the body be included in the MIRROR_SET feature. This is only effective when you add one or more features to the Features in Mirror list. Turning this option on after you have added features to the Features in Mirror list has no effect.

Choose the Add icon. The features are now listed under the Features in Mirror column. Press MB2 to move to the Mirror Plane

selection step.

Select the horizontal datum plane in the view.

Choose OK to accept your selection. Then Cancel the Instance dialog. Change to a Dashed Hidden Edges display. Notice that the hole and boss feature are now on both ends of the cylinder.

Creating the Basic Shape of the Pulley Checking the Model Shade and Rotate the view to see the model.

965

Then Restore the view, and return to a Wireframe display. Close all part files.

Adding an Instance Array of Holes In this activity, you will add a simple through hole, and then create an instance array of the hole.

Adding an Instance Array of Holes Opening the Part file Open part file fmf1_pulley_2.prt from the fmf1 subdirectory, and start the Modeling application.

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This model contains datum planes on layers 61 and 62.

Adding an Instance Array of Holes Creating a Simple Thru Hole You need to create six holes that are equally spaced around the hub. First, you will create a single thru hole.

Choose the Hole icon

, or choose Insert

Form Feature

Hole.

The Hole dialog displays default values. Choose the Simple hole type. Key in 30 for the Diameter. With the Placement Face selection step active, select the top flat face of the relief where the boss is located. Then select the relief bottom flat face, and choose OK. The positioning dialog displays, but you need to display the datum planes. Make layers 61 and 62 Selectable, so that the datum planes are selectable. On the Positioning dialog, choose Point Onto Line, and select the datum plane that passes through the axis of the cylinder, and is perpendicular to the tangent datum plane.

967 Choose the Perpendicular icon, and select the other through axis datum plane.

Key in 33 for perpendicular positioning value, and OK the dialog. Make layers 61 and 62 Invisible. Change the view display to Shaded, and check the model.

Adding an Instance Array of Holes Starting a Circular Instance Array The preferred method of creating six equally spaced holes around the hub is to use a Circular Instance Array. Then, if you edit one of the hole parameters, all holes update. Also, you can easily change the number and spacing of the holes by editing the instance array.

Choose the Instance Feature icon Instance.

, or choose Insert

Feature Operation

The Instance dialog displays five instance methods: Rectangular Array, Circular Array, Mirror Body, Mirror Feature, and Pattern Face. You will be creating a Circular Array. Choose Circular Array. The Instance dialog lists features that you can include in the array.

968 Choose the last SIMPLE_HOLE(11) from the listing window then OK the dialog. The Instance dialog provides three instance methods: General, Simple, and Identical. In most cases, you will use the General method.

Instance Methods

General - Creates an instance array from existing features and validates all geometry. An instance of a General array is allowed to cross an edge of the face. Also, instances in a General array can cross over from one face to another. Simple - Similar to a General instance array, but it speeds up the instance array creation by eliminating excessive data validation and optimizing operations. Identical - The fastest way to create an instance array; it does the least amount of validation, then copies and translates all the faces and edges of the master feature. Each instance is an exact copy of the original. You can use this method when you have a great many instances, and you are sure they are all exactly the same.

Use the General method.

Adding an Instance Array of Holes Completing the Instance Array The Instance dialog lets you specify the number of instances and the angle between them. Since you want the holes equally spaced, you can provide a ratio (360 degrees divided by 6). Key in 6 for the Number, and 360/6 for the Angle (the system will do the division for you), and OK the dialog.

969 You need to specify a rotation axis. You will use Point & Direction, since no datum axis exists in this part file. Choose Point & Direction. The Vector Constructor dialog displays. You will revolve about the ZC axis. Choose OK to accept the default direction vector. The Point Constructor dialog lets you select the reference point for the array. Choose the Arc/Ellipse/Sphere Center icon. Select an outside circular edge of the cylinder to locate the center of the instance array. The system temporarily displays locations for the holes. You can accept or reject this arrangement, and respecify the number and angle. Choose Yes to accept the array, and Cancel the Instance dialog.

The model is complete.

Adding a Circular Instance Array of a Slot In this activity, you will create a slot on the edge of the pulley, and then instance it around the perimeter of the pulley.

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Adding a Circular Instance Array of a Slot Opening the Part File Open part file fmf1_pulley_3.prt from the fmf1 subdirectory, and start the Modeling application.

You will need to select datum planes located on layers 61 and 62. Make layers 61 and 62 Selectable.

Adding a Circular Instance Array of a Slot Placing a Slot on a Datum Plane The use of a thru slot is a good practice, if the distance between the two faces that the slot passes through may change. The length of the slot is controlled by the distance between the faces, so if the distance changes, the slot length will automatically update.

Choose the Slot icon

, or choose Insert

Form Feature

Slot.

971 Use the Rectangular type, turn on Thru Slot, and OK the dialog. The Rectangular Slot dialog displays placement selections: Solid Face, and datum plane. You will place the slot on a datum plane. Select the tangent datum plane.

The direction vector should point into the material of the part, which is what you want. When the vector points into the material of the part, this means that the cutter (that creates the slot) will move into the part. If the vector pointed in the other direction the cutter would not be cutting into the part. Choose Accept Default Side, if the direction vector points into the model. Otherwise, choose Flip Default Side.

Adding a Circular Instance Array of a Slot Selecting the Horizontal Reference and Thru Faces The Horizontal Reference dialog lets you specify the direction for the length of the slot. Select the through axis datum plane that is perpendicular to the tangent datum plane.

972

Now, you need to select the through faces. Choose Solid Face, and select the flat faces on both sides of the cylinder as the thru faces.

Adding a Circular Instance Array of a Slot Specifying Parameters for the Slot The Rectangular Slot dialog lists parameter fields for Width and Depth. Key in 5 for the Width, key in 5 for the Depth, and OK the dialog. The tool solid temporarily displays.

973

Adding a Circular Instance Array of a Slot Positioning the Slot

The Positioning dialog displays. You can position the slot using Line onto Line. The long green dashed line is a temporary display that is used for positioning the slot along its horizontal center. (A slot can be positioned from an edge by selecting the proper edge of the slot.) Choose the Line onto Line icon, select the through axis datum plane as the target edge, and select the long green dashed centerline of the slot as the tool edge.

Choose OK to complete the positioning. Cancel the Rectangular Slot dialog. Change your display from wireframe to Shaded.

974

Adding a Circular Instance Array of a Slot Creating a Circular Instance Array of the Slot You need to create circular pattern of slots on the cylindrical face of the pulley.

Choose the Instance Feature icon Instance.

, or choose Insert

Feature Operation

Choose Circular Array. Choose RECTANGULAR_SLOT from the listing window and OK the dialog. Key in 38 for the Number, and 360/38 for the Angle, and OK the dialog. Choose Point & Direction. Choose OK to accept the default direction vector. On the Point Constructor dialog, choose Arc/Ellipse/Sphere Center icon, and select an outside circular edge to locate the center of the array. If the temporary display of instances looks ok, choose OK to complete the array. The shaded view looks like this, when the datum planes are not visible.

Adding a Circular Instance Array of a Slot Completing the Model with a Hole Using what you have learned, finish the pulley by adding a 15 mm. diameter simple thru hole in the center of the hub, as shown below.

975

Close the part file.

Editing Features This lesson covers basic feature modeling editing techniques. You will be editing various features on this and other similar models.

There are three methods of selecting and editing features: using the Model Navigator, using the global selection, using the Edit Feature options, or the Edit Feature toolbar icons.

976

Editing the Cylinder and Pocket In this activity, you will modify the parameters of features in this cover.

Editing the Cylinder and Pocket Opening the Part File Open part file fmf1_cover_1.prt from the fmf1 subdirectory.

This cover part is used in an assembly as shown below.

977

As a designer, you may be required to change some of its features to match other features at the next level assembly.

Editing the Cylinder and Pocket Using the Fly-Out Preference for the Resource Bar for Windows On Windows systems, by default, the Model Navigator will expand over the graphics window. There is an "automatic fly-out" preference that you can set. To turn off the automatic "fly out", choose Preferences User Interface, and toggle off the Pages Automatically Fly Out option at the bottom of the dialog. You can also control the default location of the resource bar and the home page URL. If you are working on a Windows system, choose Preferences

User Interface.

Choose the Resource Bar tab, and toggle off the Pages Automatically Fly Out option.

Then OK the dialog.

Editing the Cylinder and Pocket Starting the Model Navigator You must be in the Modeling application to start the Model Navigator. The Model Navigator lets you display the feature tree, and lets you edit features in the model.

978 Start the Modeling application. The Model Navigator is accessed differently on UNIX and Windows platforms. On UNIX systems, you can access the Model Navigator by choosing the Model Navigator icon.

If you are on a UNIX platform, choose the Model Navigator icon Model Navigator.

, or choose Tools

The Model Navigator window is shown below.

If you are on a Windows system, move the cursor over the Model Navigator tab.

Then, click MB3 and choose the Undock option from the pop-up menu. You can dock the navigator, if you prefer. To close the window, you can choose the close option.

979 You can choose Tools Model Navigator Export to Browser to view the Model Navigator in a browser window. Another way to display the Model Navigator is to double-click on the tab in the resource bar.

Editing the Cylinder and Pocket Editing the Cylinder Feature Feature parameters can be edited from within the Model Navigator by double-clicking on the feature node.

You will edit the cylinder and the hole in the model.

About the Cylinder Feature

The cylinder was created first in this model. Then features were added to it to complete the shape. Below, you can see the that if CYLINDER(0) is highlighted from the feature list (on the left), the cylinder feature is also highlighted in the view on the right. The cylinder is the first feature and it has a timestamp of zero(0). The cylinder is the parent of all the other features the model.

980

In the Model Navigator window, double-click on the CYLINDER(0) node of the feature tree. The Edit Parameters dialog displays. The options on this dialog will vary, depending on the feature that you select.

The Feature Dialog option lets you edit the parameters of the selected feature. Choose the Feature Dialog option from the Edit Parameters dialog. The dimensions for the cylinder display in the dialog.

Key in 100 for the Diameter, use the Height of 10 , and OK the Edit Parameters dialog. Choose OK again to accept the changes and close the dialog. The diameter of the cylinder is updated to the new 100 mm. value.

Editing the Cylinder and Pocket Editing a Rectangular Pocket You can also press MB3 in the Model Navigator to bring up another list of editing options for features in the model.

981 Place the cursor over RECTANGULAR_POCKET(8), and click MB3 to display the menu.

Notice that many more options display. Although this is a large list, other editing options are available from the Edit pull-down from the main menu bar. Refer to the online documentation for details on all options. Choose the Edit Parameters option. About the Rectangular Pocket

This time, the Edit Parameters dialog lets you reattach the feature or edit feature parameters.

Choose Feature Dialog on the Edit Parameters dialog. The Edit Parameters dialog lets you edit the dimensions of the rectangular pocket.

982

Key in 10 for the Y Length, and OK the dialog. Choose OK again to complete this change. The width of the rectangular pocket is now smaller.

You have completed editing two features in this model: the size of the basic body (the cylinder), and the rectangular pocket. Close all part files.

Editing the Hole and Instance Array In this activity, you will edit hole dimensions, hole type, and the instance array on the model, so that there are five counterbored holes, and not three simple holes.

983

The ability to edit multiple feature parameters on a single feature, or multiple features can save you time as a designer.

Editing the Hole and Instance Array Opening the Part File Open part file fmf1_cover_2.prt from the fmf1 subdirectory, and start the Modeling application.

Throughout the life cycle of a part or assembly, the you may have to make changes to the model as design requirements change. Certain types of changes can be accomplished by editing multiple parameters of a same feature.

Editing the Hole and Instance Array Selecting the Feature to Edit Display the Model Navigator. You will select the hole feature to edit by using the global selection option, and then use the MB3 pop-up menu to edit a feature.

About the Holes in an Instance Array

984

The first simple hole is the parent feature for the circular instance array.

The other two holes were created by the instance array. They are children of the first hole; so if the size of the first hole changes, the other two holes will update.

Choose the Select Features icon

, or choose Edit

Selection

Select Features.

Select the hole on the left side of the part. (you may have to confirm your selection), then press MB3 (make sure that the cursor is still over the feature that is selected when MB3 is pressed.) The menu lets you edit the feature parameters, edit the positioning of the hole, suppress the hole, copy it, delete it, or change the properties.

Choose Edit Parameters. The Edit Parameters dialog provides four editing functions that can be performed for this hole feature. Feature Dialog lets you edit the hole parameters.

985 Instance Array Dialog lets you edit the circular array. Reattach lets you reattach the feature to another face. Change Type lets you change to another type of hole. You will change the dimensions, type of the hole, and the number of holes in the pattern.

Editing the Hole and Instance Array Editing Dimensions of the Hole Choose Feature Dialog to see the feature parameters for the hole. Notice that for the simple hole, a diameter, depth, and tip angle can be respecified.

Change the Diameter to 8, and OK the dialog. The change will be visible when you exit the editing function. You can continue to change to other feature parameters or complete these changes. You will continue editing features before you exit the editing functions.

Editing the Hole and Instance Array Editing the Hole Type The Edit Parameters dialog again displays. Next, you will change the hole type.

986 Choose Change Type. You will change to a counterbore hole, and make it a through hole.

Choose Counterbore, turn on the Thru Hole option, and OK the dialog. Because you specified a thru hole, the system now requires you to specify a through face. Before, the holes were not through holes, so no "thru face" was needed. Select the top face of the cylinder. The Edit Parameters dialog displays the default values for the counterbore hole. You can change them, if needed. Notice that no hole depth and no tip angle is shown, but they would have been listed, if you had not specified a through hole. Notice that the hole size that you specified before (8) has remained as the hole diameter, so you do not have to respecify it.

Choose OK to accept the default values. You will not see the changes to the features until you exit the editing function.

987

Editing the Hole and Instance Array Editing the Instance Array You need to change the number of holes and the angle between them. Now the hole pattern (circular instance array) needs to be changed. Choose Instance Array Dialog on the Edit Parameters dialog. The Edit Parameters dialog displays the instance array parameters. It is currently set to three holes equally spaced over 360 degrees.

Key in 5 for the Number, and 360/5 for the Angle. (Use the General method.)

988 Choose OK to accept the new values. You will not see the changes until you are done with the edit function.

You have used three different editing options: Feature Dialog, Change Type, and Instance Array Dialog.

Editing the Hole and Instance Array Reattaching Features You will not reattach the feature, but you will choose the option to see what you get. Choose Reattach on the Edit Parameters dialog. The Reattach dialog displays. Refer to the online documentation for complete information on options on this dialog.

Choose Back, since you will not reattach the hole at this time. Choose OK on the Edit Parameters dialog to update all changes. You have the option to change another feature parameter, but you will accept your changes, and update the part.

989

Editing the Hole and Instance Array Checking the Model Rotate the part to see the back of the part, then Restore the view.

As you can see, you have changed several parameters of the same feature before you updated the model: the hole type, the size, and the number of holes in the pattern. Close the part file.

Editing Positioning Dimensions In this activity, you will edit the positioning dimensions of the counterbored through holes. The goal is to move the holes closer to the perimeter of the cylindrical body.

990

Editing Positioning Dimensions Opening the Part File Open part file fmf1_cover_3.prt from the fmf1 subdirectory, and start the Modeling application. The model is visible in a solid shaded display mode. Change to a wireframe display.

Editing Positioning Dimensions Selecting the Hole Feature Select (use MB1) the hole on the left side of the part.

991

You may have to confirm your selection.

Using MB3 positioned over the selected hole, choose the Edit Positioning option on the pop-up menu.

Editing Positioning Dimensions Editing the Perpendicular Dimension The Edit Positioning dialog display options for adding, editing, and deleting dimensions. Also, dimensions display in the view.

992

Although holes can be created without positioning dimensions, this hole has two dimensions, which display in the view. One of them is a Line onto Line type.

The other is a Perpendicular type.

Choose the Edit Dimension Value option. Since two dimensions display, you must indicate which one you want to edit. Select the perpendicular dimension (p42) from the graphics window. The Edit Expression dialog displays the current value for the expression named p42. Key in 40 for the new value.

993

Choose OK on the dialog. Since you can continue to edit dimensions, the dialog remains. Choose OK two more times. The model updates.

Editing Positioning Dimensions Checking the Model Change the display to Shaded. The bolt hole circle diameter is increased to the new value.

994

The counterbore holes need to be checked to ensure that there is enough material on the edges. By making the bolt hole circle larger, the counterbore portion of the hole may break through the edges of the part. Rotate to check that the holes have not broken through the edges of the cylinder, and then Restore the view.

There appears to be enough material for the new change. Close the part file.

Editing the Chamfer Parameters In this activity, you will use the icons on the Edit Feature toolbar, and the options on the Edit pull-down menu to modify the model to look like this.

995

Editing the Chamfer Parameters Opening the Part File Open part file fmf1_cover_4.prt from the fmf1 subdirectory, and start the Modeling application.

You will edit the chamfer by using some of the Edit Feature Toolbar options.

Editing the Chamfer Parameters Selecting the Chamfer Do not display the Model Navigator, because you will be using the Edit Feature toolbar options.

996

Choose Edit Feature Parameters

, or choose Edit

Feature

Parameters.

The Edit Parameters dialog lists all features in this model.

Choose CHAMFER(20) from the Edit Parameters feature list. The chamfer highlights in the list and in the view.

About the Chamfer

The chamfer was modeled as an aid to the assembly with other components (to help align the part). The chamfer values can be adjusted to accommodate the type of the assembly process that is required in the next level of assembly.

997

Choose OK to accept this feature.

Editing the Chamfer Parameters Changing the Size of the Chamfer You can edit the feature parameters of the selected chamfer, and add or remove edges to the feature. Notice, that unlike the holes, you cannot change the type of chamfer. To do that, you would have to delete, or suppress this chamfer, and create another one in its place.

Choose Feature Dialog. Key in 1 for the Offset, and OK the dialog. Choose OK again. The Edit Parameters displays again, so you could add other edges to the chamfer feature. Choose OK until the model updates. The size of the chamfer has updated to the new 1 mm. value.

You have completed this lesson. Close all part files.

998

-Feature Modeling-Additional TopicsCones This lesson will show you how to use the Cone

creation methods:

Diameters and Height, Diameter and Half Angle, Diameter, Height, and Half Angle, and Two Coaxial Arcs.

Cones may be truncated or not.

Diameters, Height Method

In this activity, you will create this truncated cone by specifying a diameter, height, and origin.

999

Diameters, Height Method Opening the Part Open part file fmf2_prim_1.prt from the fmf2 subdirectory, and start the Modeling application. Diameters, Height Method Starting the Feature

The Cone option lets you create a primitive cone by specifying its orientation, size, and location.

Choose the Cone icon

or Insert

Form Feature

Cone.

The Cone dialog lists five cone creation methods: Diameters, Height; Diameters, Half Angle; Base Diameter, Height, Half Angle; Top Diameter, Height, Half Angle; and Two Coaxial Arcs.

The Diameters, Height method lets you specify three parameters: base diameter, top diameter, and height.

1000

Choose the Diameters, Height option.

Diameters, Height Method Specifying Parameters You must specify a direction for the cone. The Vector Constructor dialog displays. This dialog is used to define the direction in which a cone will be created.

Choose ZC Axis option.

1001 The direction vector displays at the location of the WCS.

OK the Vector Constructor dialog to accept the direction vector. You must use positive values for cone parameters. The Base Diameter must be greater than zero. (It cannot be zero.) The Top Diameter can be zero, which will create a pointed cone, or greater than zero for a truncated cone. This value can be larger than the base diameter value. Key in 3 for the Base Diameter, 1 for the Top Diameter, and 4 for the Height.

OK the dialog.

Diameters, Height Method Specifying the Origin The Point Constructor dialog displays to help you specify the origin (arc center) of the base of the cone.

1002

You can place the origin of this cone slightly away from the origin of the WCS, but you will still keep it on the same XC-YC plane. Key in an XC value of -2, YC value of 3, and ZC value of 0, and OK the dialog. Fit the view. The truncated cone is created at the specified origin.

Close all part files.

Diameters, Half Angle Method

1003 In this activity, you will create this truncated cone by specifying the Diameters, and Half Angle.

Diameters, Half Angle Method Opening the Part Open part file fmf2_prim_1.prt from the fmf2 subdirectory, and start the Modeling application.

Diameters, Half Angle Method Starting the Feature Choose the Cone icon

or Insert

Form Feature

Cone.

The Cone dialog displays. The Diameters, Half Angle method lets you specify the base and top diameters, and a half angle between the axis and the side of the cone. Valid half angle values range between .0001 and 89.9999 degrees.

Choose Diameters, Half Angle.

1004

Diameters, Half Angle Method Specifying Parameters This time, you can point the cone direction along the positive XC axis. Choose XC Axis

and OK the dialog.

Key in a Base Diameter of 2.5, a Top Diameter of 1, and a Half Angle of 15, and OK the dialog. You can place the cone origin (base) two inches away from the WCS along its negative XC axis. Key in an XC value of -2, a YC value of 0, and a ZC value of 0 and OK the Point Constructor dialog. The cone is created along the XC axis. If dashed hidden edges were used, the view would look like this.

Close all part files.

Diameter, Height, Half Angle Method In this activity, you will create this truncated cone by specifying the diameter, height, and half angle.

1005

Diameter, Height, Half Angle Method Opening the Part Open part file fmf2_prim_1.prt from the fmf2 subdirectory, and start the Modeling application.

Diameter, Height, Half Angle Method Starting the Feature Choose the Cone icon

or Insert

Form Feature

Cone.

With the Base Diameter, Height, Half Angle method, you define the base diameter, the height of the cone, and a half angle (between the axis and the side of the cone). A valid half angle is .0001 to 89.9999 (degrees). For the Top Diameter, Height, Half Angle cone creation method, you must specify the top diameter instead of the base diameter. Otherwise, the procedure is the same as described here. Choose Base Diameter, Height, Half Angle.

Diameter, Height, Half Angle Method Specifying Parameters The Vector Constructor dialog displays. Choose YC Axis as the direction. You want the vector pointing in the negative direction.

1006 Choose Cycle Vector Direction and OK the dialog. In this method, the half angle value and height value will determine whether the cone will be truncated. Key in the Base Diameter of 4, Height of 1, Half Angle of 15, and OK the dialog. OK the Point Constructor dialog to accept the current base point values.

Close all part files.

Two Coaxial Arcs Method In this activity, you will create this truncated cone by selecting two coaxial arcs.

Two Coaxial Arcs Method Opening the Part Open part file fmf2_prim_1a.prt from the fmf2 subdirectory, and start the Modeling application.

1007 The part file contains two circles on layer 41. The work layer is 1, which is where you will create the cone.

Two Coaxial Arcs Method Starting the Feature Choose the Cone icon

or Insert

Form Feature

Cone.

The dialog of cone methods displays. The Two Coaxial Arcs method lets you create a cone by selecting a base arc and a top arc. The arcs do not have to be parallel. Choose the Two Coaxial Arcs method.

Two Coaxial Arcs Method Selecting Arcs Select the larger circle as the base arc. Select the smaller circle as the top arc. The system creates the cone from the selected arcs. The system uses the base arc to establish the location of the cone.

1008 This primitive cone is not associated to the arcs. So, if you edited an arc, the cone would not change (update). The shaded model looks like this.

If you had selected the smaller arc as the base, and the larger one as the top, the model would look like this. Notice that the location of this cone is that of the smaller base arc.

Cancel the dialog and close all part files.

Spheres This lesson covers creating two Sphere Diameter and Center, and Select Arc.

features:

1009

Diameter, Center Method In this activity, you will create a Sphere by specifying a diameter and the center of the sphere.

Diameter, Center Method Opening the Part Open part file fmf2_prim_1.prt from the fmf2 subdirectory, and start the Modeling application.

Diameter, Center Method Starting the Feature

Choose the Sphere icon

or Insert

Form Feature

Sphere.

You can create the Sphere primitive either by specifying a diameter and center location, or by selecting an existing arc.

1010 Choose Diameter, Center.

Diameter, Center Method Specifying the Diameter and Origin

The dialog displays a diameter field. Only positive values can be used. You can make this sphere 2 inches in diameter. Key in a diameter of 2 and OK the dialog. You need to specify an origin (center point) of the sphere. The Point Constructor dialog displays to assist you in specifying the origin of the sphere. You will place the center of the sphere at the WCS. Make sure that the WCS option is turned on, and that the XC, YC, ZC base point values are 0 (zero) and OK the Point Constructor dialog. Cancel the Sphere dialog. The sphere is created, but just looks like a circle in the view.

Shading your solid occasionally will help you to visualize the part as you work. Close the part file.

Select Arc Method

1011 In this activity, you will create a sphere from a larger circle, and then create another sphere using a smaller circle and subtract the smaller sphere from the larger sphere.

Select Arc Method Opening the Part Open part file fmf2_prim_1a.prt from the fmf2 subdirectory, and start the Modeling application. This part file contains two circles on layer 41. The work layer is 1, where you will create the spherical solid body.

1012

Select Arc Method Starting the First Feature

Choose the Sphere icon

or Insert

Form Feature

Sphere.

For the Select Arc method, the system uses the size and orientation of a selected arc to create a primitive sphere. The arc center defines the origin of the sphere and the arc diameter defines the diameter of the sphere. The sphere is not associated to the selected arc. Choose the Select Arc method. Select the larger arc. The sphere is created from the larger circle.

Select Arc Method Creating the Smaller Sphere and Subtracting it from the Larger

Since you can continue to create spheres this way, you can create another sphere using the smaller circle, and subtract it from the larger sphere. Select the smaller arc to create the small sphere. Boolean operations let you subtract, intersect, unite, or create this new feature. Choose Subtract as the Boolean operation so that the smaller sphere is removed from the

1013 larger one. Rotate the model, use Format Shade it.

Layout

Regenerate to update the silhouettes, and then

Close all part files.

Tubes This lesson covers creating Tube

features.

Creating a Tube Along a Spline

1014

In this activity, you will create two tubes, using two methods. The upper tube will be a single segment tube, which will have B-Surfaces. The lower tube will be a multiple segment tube, which will have toroidal and cylindrical faces.

Creating a Tube Along a Spline Opening the Part Open the part file fmf2_tube_2.prt from the fmf2 subdirectory, and start the Modeling application. The two splines in this part file are rational (general) splines with a degree of 3, having 13 poles, and 4 segments. They were created by joining arcs and lines.

You can find this information by choosing Information, Object, and selecting both splines.

Creating a Tube Along a Spline Starting the Feature

The Tube option lets you create a single solid body by sweeping inner and outer diameters (circular cross-sections) along a path (guide string).

1015

The guide string objects (curves, edges, faces) must be tangent continuous. Tube features are useful for creating wire bundles, harnesses, tubing, cabling, or piping.

Choose the Tube icon

or Insert

Form Feature

Tube.

You will create two tubes using the splines as the paths, and then you will evaluate the final faces that you obtain. You must specify all the parameters before you can select the guide string. Outer Diameter - This value must be greater than the Inner Diameter. Use 1 as the Outer Diameter. Inner Diameter - This value must be greater than or equal to zero. Use 0 as the Inner Diameter.

Creating a Tube Along a Spline Specifying a Single Segment Output You also need to select an output type. When you use Single Segment as the output type, the resulting tube will have a single BSurface face for each curve. Once specified, this option cannot be changed during editing of the Tube. Choose the Single Segment option as the Output Type. Choose OK. Since the parameters are specified, you can select the guide string.

1016 You can use options on the dialog (Solid Face, Solid Edge, Curve, or Chain Curves) to specify the guide string (path), or you can simply select the curves in the view. Select the upper spline, and choose OK. The single segment tube is created.

Creating a Tube Along a Spline Specifying a Multiple Segment Output The Tube dialog redisplays, so you can create the multiple segment tube using the other spline, which is an exact copy of the first spline. When you select a guide string comprised of spline(s), using Multiple Segment, you will get multiple faces for each spline in the string, and they will be analytic faces. Check that Multiple Segment is selected. Use 0 as the Inner Diameter. Use 1 as the Outer Diameter and choose OK on the dialog. You can select the guide string. Select the lower spline, and choose OK. Because another solid body exists in the part file, you get the dialog of boolean operations. Choose Create as the Boolean operation. The multiple segment tube is created on the lower spline.

1017

Notice that the multiple segment tube has more faces. The face types are different on these two tubes.

Creating a Tube Along a Spline Checking the Objects You can check to see the number and types of faces that were created. Choose Information

Object.

The Class Selection dialog displays. Choose Type. The Select by Type dialog displays. Choose Face and OK on the Select by Type dialog. Select the outer face of the upper tube (single segment). Then select the five faces of the lower tube (multiple segment)

Choose OK until the Class Selection dialog closes.

1018 The Information window displays information about the faces that you selected. Read the data in the Information window. Notice that the Single Segment tube has a B-Surface face, but the multiple segment tube has toroidal and cylindrical faces. Close the Information window. The system labels each face and direction vector. B-Surfaces have U and V direction vectors, but cylindrical and toroidal faces do not have U and V vectors.

Refresh the view.

Creating a Tube Along a Spline Using Face Analysis Display With your cursor in the view, press MB3 and choose Display Mode From the main menu bar, choose Analysis dialog.

Face

Face Analysis.

Radius to display the Face Analysis

The Face Analysis dialog is explained in the Free Form Modeling course, but you will use all the defaults on the dialog and look at the surfaces of the two tubes. Select the outer face of the upper tube (single segment). Select the five faces of the lower tube (multiple segment). Choose Apply.

1019 The upper solid (single segment used) has a smoother color gradation on the B-Surfaces. The lower solid (multiple segment used) has distinct color changes where the toroidal and cylindrical faces meet.

If you are using a 2D graphics driver, your display will not look like the picture above, but the two tubes will still have differing color patterns. Refer to the Unigraphics NX online help for details about the ranges displayed on the right side of your view. With your cursor in the view, press MB3 and choose Display Mode return to wireframe mode.

Wireframe to

Close the part file.

Creating a Tube Along Arcs and Lines In this activity, you will create two tubes, along multiple segment splines.

Creating a Tube Along Arcs and Lines Opening the Part

1020 Open the part file fmf2_tube_1.prt from the fmf2 subdirectory, and start the Modeling application. Four curves display. These curves are on layer 1. The work layer is layer 11. These four curves are tangent contiguous.

Creating a Tube Along Arcs and Lines Starting the Feature

Choose the Tube icon

or Insert

Form Feature

Tube.

Creating a Tube Along Arcs and Lines Specifying Parameters for Single Segment

The Tube dialog displays. You must specify all the parameters before you can select the guide string. Inner Diameter - This value must be greater than or equal to zero. You will be creating a cable in this activity, so you need to use a zero inner diameter value. Use 0 as the Inner Diameter. Outer Diameter - This value must be greater than the Inner Diameter. Use 1 as the Outer Diameter. You also need to select an output type. Single Segment - If the guide string consists of lines and/or arcs (as in this part file), you will get a single face for each curve, regardless of the segment choice

1021 (Output Type). However, using Single Segment results in B-Surface faces, whereas Multiple Segment results in analytic faces. You will use the Single Segment option and save the solid on layer 11. Choose Single Segment. Choose OK.

Creating a Tube Along Arcs and Lines Selecting the Guide String Since the parameters are specified, you can select the guide string. You can use options on the dialog to specify the guide string (path), or you can simply select the curves in the view. This part file contains three arcs and one line, which you will use as the guide string (path) for the tube feature. These curves are tangent and continuous. If the guide string consists of multiple objects, they must be tangent and contiguous (no breaks in the string). The curves in the part file satisfy this condition. Select all four curves as a guide string and OK the dialog. The solid, single segment cable is created. Notice that it has multiple faces.

Cancel the dialog.

Creating a Tube Along Arcs and Lines Finding Information on the Faces You can check to see the number and types of faces that were created.

1022 Choose Information

Object to display the Class Selection dialog.

Choose Type, Face, and OK the Select by Type dialog. Choose Select All and OK the Class Selection dialog. The Information window displays information about all faces for this solid. Scroll through the information and review the data provided. Notice that with Single Segment, the faces are B-Surfaces, and the ends of the cable are trimmed planar surfaces.

Close the Information window. In the view, the system labels each face and direction vector. B-Surfaces have U and V direction vectors. Refresh the view.

Creating a Tube Along Arcs and Lines Setting up Selectable Layers Now, you need to create a multiple segment tube on a different layer, so that you can compare the faces of the multiple segment tube. Choose Format

Layer Settings to display the Layer Settings dialog.

Make layer 15 the Work Layer. You will use curves located on layer 5. These curves were copied from layer 1, and then transformed (moved) vertically.

1023 Make layer 5 Selectable. Choose OK on the dialog to apply and close the Layer Settings dialog. Another set of identical curves are displayed above the first model.

Creating a Tube Along Arcs and Lines Starting the Next Tube Feature Choose the Tube icon

or Insert

Form Feature

Tube.

The Tube dialog displays. Use 1 as the Outer Diameter. Use 0 as the Inner Diameter. This time, you will use Multiple Segment. Multiple Segment - If the guide string consists of lines and/or arcs, you will always get a single face for each curve, regardless of the segment choice. However, using Multiple Segment results in analytic faces, like cylindrical and toroidal faces. Check that Multiple Segment is selected. Choose OK. This time, you need to select the curves in the upper portion of the view. Select all four curves as a guide string and OK the dialog. Since another solid body exists in the part file, the list of Boolean operations displays. Choose Create on the dialog of Boolean operations. Cancel the Tube dialog.

1024 The second tube is created.

Creating a Tube Along Arcs and Lines Finding Information on the Faces Although both tubes may look the same, their faces are quite different. You can check to see the types of faces that were created. Use Information

Object, Type, Face, OK.

In the view, select all faces on both tubes. (Drag a box around both solids to grab all faces.) Choose OK on the Class Selection dialog. The Information window displays information about all faces for both solids. Scroll through the information and review the data provided on the tube features. Notice that the new solid (created using Multiple Segment) has cylindrical, and toroidal faces, not B-Surfaces. In both solids, the ends of the cable are trimmed planar surfaces. Close the Information window. Also, notice that the direction vectors are different. U-V direction vectors do not display for cylindrical, toroidal, and planar faces, but are displayed for the B-Surface faces. U and V direction vectors are explained in greater detail in theFree Form Modeling course. Choosing Analysis, Face, Radius in a Face Analysis display mode will show the following results.

1025

Close the part file.

Cylindrical Pockets This lesson covers creating cylindrical pockets. The information on creating rectangular and general pockets is covered in the Feature Modeling Fundamentals course.

Creating a Cylindrical Pocket In this activity, you will create a cylindrical pocket on the top face of this T-shaped solid body.

1026

Creating a Cylindrical Pocket Opening the Part Open the part file fmf2_pocket_cylindrical.prt from the fmf2 subdirectory, and start the Modeling application.

Change to a Dashed Hidden Edges display.

Creating a Cylindrical Pocket Starting the Cylindrical Pocket Pockets are recessed features in solid bodies.

Choose the Pocket icon

or Insert

Form Feature

Pocket.

A list of pocket types displays.

A Cylindrical pocket is different from a simple hole because you can specify straight or tapered sides, with or without a bottom corner radius.

1027 Choose Cylindrical as the pocket type.

Creating a Cylindrical Pocket Specifying the Placement Face The Cylindrical pocket dialog displays placement face options.

You must place the cylindrical pocket on a planar placement face of a solid body, or on a datum plane. Select the top face near the left side, like this.

Creating a Cylindrical Pocket Specifying the Parameters The dialog now displays default dimensions for the pocket.

1028

Cylindrical Pocket Parameters

The pocket diameter is measured on the planar face (or datum plane). The depth is measured from the origin point along the specified direction vector. The depth must be greater than the floor radius. The floor radius is the blend between the pocket sides and floor. The value must be positive, and less than or equal to the radius of the pocket. A zero value will create a pocket with sharp corners. The taper angle is the draft angle applied to the pocket walls. It must be greater than or equal to zero. A zero value creates walls that are straight (not tapered).

All values must be positive. Key in the parameters for the Pocket Diameter as 1.0, the Depth as 1.0, the Floor Radius as 0.5, and the Taper Angle as 0, and OK the dialog. The pocket is displayed temporarily, along with the temporarily relocated WCS.

1029

Creating a Cylindrical Pocket Positioning the Pocket The Positioning dialog displays, so that you can specify positioning dimensions.

You will position this pocket using the Perpendicular

positioning method.

Choose the Perpendicular icon. Select the bottom front edge of the model as the target edge.

Select the hole of the cylindrical pocket as the tool edge.

The Set Arc Position dialog displays options for End Point, Arc Center, and Tangent Point. Choose Arc Center on the Set Arc Position dialog to establish the location for the

1030 positioning dimension. The Create Expression dialog displays. Key in 1.5 as the expression value, and OK the dialog.

Creating a Cylindrical Pocket Completing the Positioning You have created one positioning dimension. You could create another Perpendicular dimension, but you do not have to do this at this time. You can always add positioning dimensions later. Choose OK on the Positioning dialog to accept the location of the pocket. The pocket is created.

Close all part files.

General Pads This lesson covers creating General Pad form features.

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Creating a General Pad In this lesson, you will use the yellow curves on the planar surface to create a General Pad on the curved surface of the solid body.

Creating a General Pad Opening the Part Open part file fmf2_pad_general.prt from the fmf2 subdirectory, and start the Modeling application. The part file contains yellow curves.

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Creating a General Pad Starting the General Pad Feature Choose the Pad icon

or Insert

Form Feature

Pad.

The Pad dialog displays options for Rectangular and General. General pads provide you with more design flexibility than you have with the rectangular pad. The option lets you define a pad with almost any shape. Choose General. The General Pad dialog displays.

Since the Attach Pad option (near the bottom of the dialog) is turned on, the pad will be united with the solid body. (To create a separate body, the Attach Pad must be off.) Attach Pad lets you sew the pad to a target sheet body, or subtract the pad from a target solid body. If this option is not selected, the pad will be created as a separate solid body. Use the Attach Pad option turned on.

1033 Confirm Upon Apply opens the Confirm Upon Apply dialog after you choose Apply, letting you preview the results, and accept, reject or analyze them.

Creating a General Pad Specifying a Placement Face

The Placement Face icon

is active.

Placement, Top, and Corner Radii for the General Pad

Placement Radius defines the blend radius between the placement face (the bottom of the pad) and the sides of the pad Top Radius defines the blend radius between the top face and the sides of the pad. Corner Radius defines the blend radius placed on the corners of the pad. A corner is located at a joint between two outline curves/edges whose tangent difference varies by more than the angle tolerance.

The placement face is one or more selected faces, or a single plane or datum plane. The bottom of the pad follows the contours of the selected face(s). The placement outline curves (described below) are projected onto the placement face, if necessary. The first selected face or associative datum plane will identify the solid or sheet body in which the pad is to be placed, if the optional target body is not specified. (If you select a fixed datum plane, then you must specify a target body.) The rest of the faces can be from any body in the part. You can use the Filter options to mask your selection for the placement faces. Set the Filter to Faces.

1034 You need to select the placement face of the pad. Select the curved face as the placement face. The vector indicates the direction for the pad.

The Placement Radius option lets you add a fixed radius or variable (law controlled) blend to the edges on the placement face. You will use 0.0 and Constant for the Placement Radius parameters, Top Radius parameters, and Corner Radius parameters. Reverse Pad Region If you select profile curves that are open instead of closed, a vector displays showing on which side of the profile the pad is to be built. You can use the Reverse Pad Region option to create the pad on the opposite side of the profile. If the pad has multiple openings and you have specified a floor radius, you must attach at least one face on the floor to all of the side walls of the pad. Otherwise, blends are not produced. If you specify a Placement Radius, Reverse Pad Region is disabled.

Creating a General Pad Specifying a Placement Outline and Taper The placement outline defines the bottom of the pad on the placement face. Choose the Placement Outline icon. Before the outline is selected, the dialog displays the taper angle information.

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You can specify a Taper Angle from the top outline to be used in generating the placement outline. A taper angle can only be used if either a placement or top outline is selected, but is not if both are used. You can make the taper angle Constant, Law Controlled (where you define a single law relative to the top outline), or By Outline (where you define a law for each curve in the top outline). If you choose the By Outline option, the curve (or edge) whose law is being defined is highlighted, and an arrow shows the direction that the law will be applied. The Taper Angle is relative to the face normal or a fixed vector, that determines how the sides of the pad are angled from the placement face to the top face. Use a Constant taper angle of 5 degrees. The taper angle can be measured relative to the following:

Use the Relative to Face Normals option. If you specify a vector, an arrow is displayed that shows this vector direction whenever this step is active. If you select a datum axis, the Relative to: option automatically changes to Selected Datum Axis. However, if you select any curves to define the placement outline, any selected datum axis is automatically deselected. Once curves are selected, you can no longer select any datum axis unless you first deselect all the curves. You will use the yellow curves as the placement outline. You can use the Filter options to mask your placement outline selections if needed. Change the Filter options to Curves. Select the yellow curves by dragging a box around them.

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The arrow in the display shows the starting point and direction of the outline. Reverse will reverse the arrow's direction. The starting point and direction are critical when using laws, and for alignment when both the placement and top outlines are defined with curves.

Creating a General Pad Placement Radius and Theoretical or Tangent Intersections

The placement outline can be related to the placement radius in one of two ways: Theoretical or Tangent. (Remember, you used zero as the placement radius.) Tangent - The placement outline curves can represent the tangency point between the placement radius and the placement face. Theoretical - The placement outline curves can represent the theoretical intersection of the sides of the pad and the placement face.

Since you did not specify a radius (that is, you used zero values), either Theoretical, or Tangent option will produce the same pocket. Use the Theoretical option on the dialog.

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Creating a General Pad Specifying Top Faces

Next you need to specify the Top Face. Choose the Top Face icon. You can now select the top face, or specify an offset/translation from the placement face. The middle of the dialog displays options for the specification of the top face. You could specify top faces in several ways: select a specific face, or specify that the top face will be Offset from the placement face by a distance value (what you will be doing), or specify that the top face is a Translation of the placement face and use Define Translation Vector to define the direction for the translation. You will be offsetting the top from the placement face at a distance of ten. Use Offset for the Top Face. Change the From Placement value to 10.

Creating a General Pad Specifying the Placement Outline Projection Vector

Placement Outline Projection Vector outline curves if desired.

is used to define the projection of the placement

Choose the Placement Outline Projection Vector icon.

1038 The middle of the dialog changes. These options, let you control the outline projection onto the placement face.

Since the outline curves are not on the placement face, you can project them using Normal to Plane of Curves, or you can specify a direction. Use the Normal to Plane of Curves option located in the middle of the dialog. Using all of the radius values set to zero, choose Apply to create the pad.

Cancel the dialog. Editing the pad is similar to editing other features. When you start the edit, you will be presented with edit options that look a lot like the creation options. Double-click on the pad feature that you just created. Notice that the General Pad dialog displays, so you are able to edit many of the parameters. Cancel the Pad dialog. Close all part files.

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Sweep Along Guide This lesson covers creating Sweep Along Guide features. The Sweep along Guide option lets you sweep a closed or open section string along a guide string to create a solid or sheet body. Both the section and guide strings can be composed of a sheet body, curves, solid edges, and faces. A solid or sheet will be created based on the Modeling preferences and selected section string used.

Swept features are associated with the section string; therefore, if you edit the generator geometry, the features change.

Sweeping Circles along a Guide String In this activity, you will sweep the two circles along the yellow guide string of five curves to create this model.

Sweeping Circles along a Guide String Opening the Part Open part file fmf2_sweep.prt from the fmf2 subdirectory, and start the Modeling application.

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Sweeping Circles along a Guide String Starting the Feature Choose the Sweep along Guide icon Guide.

or Insert

Form Feature

Sweep along

The Sweep Along Guide feature, Extruded Body, and Revolved Body features are all types of "swept" features. In this part, the arc centers of the two circles are also at the endpoint of the guide string that is on the XC-YC plane. However, this positioning condition does not have to exist. For example, the section string and guide string could be at different locations like this.

The Sweep Along Guide dialog displays section string options: Solid Face, Solid Edge, Curve, Chain Curves, and Sheet Body.

Sweeping Circles along a Guide String Selecting Section and Guide Strings You will be sweeping the section string along one guide string to create a tube.

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Notice that the dialog is the same as for other swept features, so the section string could consist of solid faces, solid edges, curves, and sheet bodies. Select both circles as the section string, which will form the diameters of the tube. Choose OK to complete the section string selection. You need to select a guide string, so the Sweep along Guide dialog displays guide string selection options: Solid Face, Solid Edge, Curve, and Chain Curves. As with other swept features, you have the option to select solid faces, edges, and curves. Select the five curves in the guide string (on the XC-YC plane), and choose OK to confirm that the guide string has been completely selected. You can now enter the offset values. Although offsets work the same way that they did for extruded bodies, you will not be using offsets, so you will not have to enter any values in these fields. Use zero ( 0 ) values on the dialog, and choose OK to create the sweep. The circles are now swept along the full length of the guide string.

Cancel the dialog. Shade the solid walled body. Close all part files.

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Datum Coordinate Systems This lesson covers the creation of the Datum CSYS feature. A Datum CSYS is an associative datum coordinate system with or without datum planes and datum axes. The Datum CSYS is different in appearance from a non-associative CSYS.

A Datum CSYS is a feature (DATUM_CSYS), and it displays in the Model Navigator. Like other features, you can edit it. Uses for Datum CSYS Features

Some uses for Datum CSYS features are listed here. Datum CSYS features are useful if you need associativity to ensure that downstream features are updated automatically when the geometries used to define the CSYS are modified. Datum CSYS feature's individual datum planes can be used as for placement planes for sketches. The individual datum planes and axes of the Datum CSYS may be used to position downstream features. Any one of the Datum CSYS axes may be used to define a direction wherever a directed geometry is required in the definition of a feature. The individual components of the feature (that is, the datum planes and datum axes) may be used for mating conditions in part positioning.

Creating Datum CSYS Features In this activity, you will create datum coordinate systems in model space, and at a location on a model.

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You will create the Datum CSYS without components. Later, you will edit the Datum CSYS and add the components.

Creating Datum CSYS Features Opening the Part Open the part file fmf2_datum_csys.prt from the fmf2 subdirectory and start the Modeling application. Although no objects display in the view, the part file does contain a solid body on an invisible layer. Choose WCS

Display to display the current WCS.

The WCS is positioned at the absolute coordinate system location.

Choose WCS

Display to turn off the display of the current WCS.

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Creating Datum CSYS Features Creating the Datum CSYS Without Components Choose the Datum CSYS icon

or choose Insert

Form Feature

Datum CSYS.

The CSYS Coordinate dialog displays.

The Create Components option on the CSYS Constructor dialog lets you create the datum planes, datum axes, and origin when the Datum CSYS is created. If you create the Datum CSYS with Create Components toggled on, the CSYS symbol displays its axes and datum plane components. Created this way, the Datum CSYS is composed of datum axes, datum planes and origin components that are selectable for use during the creation of other objects. Once components are created, you cannot edit the Datum CSYS and turn them off later. If you toggle off the Create Components option, the Datum CSYS is created without the components, and the CSYS looks like a normal coordinate system symbol, except in a different color. Toggle off the Create Components option, so that the datum planes and axes will not be created.

Creating Datum CSYS Features Creating a Datum CSYS at Absolute The CSYS Constructor dialog lets you specify the location of the datum coordinate system.

1045 The dialog contains seven options for the placement of a datum coordinate system:

CSYS Constructor Icons

Inferred

lets the system select the location based on you selection in the view.

Origin, X-Point, Y-Point lets you specify an origin and the X and Y point to control the Datum CSYS location. Three Planes lets you select three planar objects. The normals of the selected planes will define the direction of the three axes. X-Axis, Y-Axis, Origin lets you specify an origin and the X axis and Y axis to control the Datum CSYS location. Offset from Csys lets you offset from an Existing CSYS. You need to select the Csys, and enter to offset values. Absolute CSYS System.

lets you create the Datum CSYS at the Absolute Coordinate

CSYS of Current View view.

lets you create the Datum CSYS based on the current

You want to model a part that is entirely referenced to the absolute coordinate system. The easiest way to do that is by creating a Datum Csys at absolute. The Absolute CSYS Coordinate System.

icon creates three datum planes and axes at the Absolute

Choose the Absolute CSYS icon

on the CSYS Constructor dialog.

The system temporarily displays the location of the Datum CSYS.

Now, all that is needed is to ok the dialog.

1046 OK the CSYS Constructor dialog. The Datum CSYS is created.

Notice that its color is different from the work coordinate system color. You can verify this by using Information CSYS, and choose OK.

Object, Type, CSYS, select the Datum

The Information window will display information about the Datum CSYS.

Creating Datum CSYS Features Editing the Datum CSYS You can edit the Datum CSYS and turn on the creation of the components. Remember, when the components are created, you cannot turn them off later.

Choose the Edit Feature Parameters icon Parameters.

, or choose Edit

Feature

The Edit Parameters dialog displays, and lists the Datum CSYS that you just created. Choose DATUM_CSYS(1), and OK the Edit Parameters dialog. The CSYS Constructor dialog displays. To make the Datum CSYS as a component, you need to turn on the Create Components option. Toggle on the Create Components option, and choose OK until all editing dialogs are dismissed and the feature is complete. Fit the view.

1047 The associative components of a Datum CSYS include its datum axes, datum planes and its origin point. Each is separately selectable to support the creation of other objects.

Remember, you also cannot delete a Datum CSYS without deleting any features associated with it.

Creating Datum CSYS Features Setting Up for the Next Datum CSYS Next, you need to create a datum coordinate system at a specific location on a block, like this.

Choose WCS

Display to display the WCS.

First, you need to change the work layer, and make the prior datum coordinate system invisible. Change the Work Layer to 10. Make Layer 61 Invisible. Fit the view.

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Creating Datum CSYS Features Creating a Datum CSYS at the Corner of a Block You want a set of datums related to this block. You want them located on the block, like this.

Choose the Datum CSYS icon

or choose Insert

Form Feature

Datum CSYS.

The CSYS Coordinate dialog displays. Check that Create Components is toggled on so that the datum planes and axes will be created. X-Axis, Y-Axis, Origin the Datum CSYS location.

lets you specify an origin and the X axis and Y axis to control

Choose the X-Axis, Y-Axis, Origin icon

on the CSYS Constructor dialog.

Creating Datum CSYS Features Making the Selections First, you need to specify the X axis, as stated by the status line. Select the front lower edge in its right half for the X-Axis.

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The vector displays the direction of the X axis for the datum coordinate system that you are about to create. (In the view, the work coordinate system is located at the absolute coordinate system.)

Next, you need to specify the Y axis, as stated by the status line. Select the front left edge in its upper half for the Y-Axis.

Now, the direction of the Y axis is also indicated with a conehead.

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Finally, you need to select the origin for the CSYS. Select the back lower left corner as the Origin.

A system marker displays at the location of the origin.

You need to OK the dialog to complete the feature. Choose OK on the CSYS Constructor dialog.

1051 Zoom in on the corner to view the feature more easily.

Fit the view.

Creating Datum CSYS Features Rotating the Block Now you are going to Transform Rotate the block to see the associativity. Choose Edit

Transform.

The Transform dialog displays. It is like the Class Selection dialog, but is used to select objects to transform. Refer to the Unigraphics NX online help for details on all options. Select the block and OK the Transformation dialog. The Transformations dialog displays methods for transforming objects. Refer to the Unigraphics NX online help for details on all options. You will be translating (rotating) the block. Notice that there are three different rotation options on the Transformations dialog. Choose Rotate About a Line. The Transformations dialog now lets you rotate using a line defined by: two points, or an existing line, or a point and vector. You will rotate using two points to define the line of rotation.

1052 Choose Two Points. The Point Constructor displays, so you can use options on the dialog to select or specify the points. Select the two end points as indicated. (These specify the end points of the line of rotation.)

The system displays asterisks at the two endpoints that you selected. The Transformations dialog requires that you specify the angle of rotation. Key in 20 as the angle of rotation, and OK the dialog. The Transformations dialog lets you move, copy, and make other types of transformations. You can choose Move to complete the 20 degree rotation and watch how the datum coordinate system updates. Choose Move on the dialog of Transformation options. The model updates: the block is rotated, and the datum coordinate system updates. Notice that the datum Csys is associated with the block.

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The Transformations dialog continues to display to let you move, copy, and make other types of transformations before you leave the function. Cancel the Transformations dialog. Close all part files.

Instance Arrays The Instance Feature icon lets you create an instance array from existing features. An Instance is a shape-linked feature, similar to a copy. This lesson covers Instance Features that were not included in the Feature Modeling Fundamentals course. You will find activities for creating the following instance features. Rectangular Array

Mirror Body

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Pattern Faces

Creating a Rectangular Instance Array In this activity, you will create a Rectangular Instance Array of a simple hole.

This option lets you create a linear array of instances from one or more selected features. Rectangular instance arrays can be either two-dimensional in XC and YC (several rows of features) or one-dimensional in XC or YC (one row of features). These instance arrays are generated parallel to the XC and/or YC axes based on the number and offset distance you enter. You will create a rectangular instance array of the hole along the top flat face of this part. You cannot instance the following features: Hollows, Blends, Chamfers, Offset sheets, Datums, Trimmed sheet bodies, Instance sets, Taper features, Free form features, or Trimmed features

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Creating a Rectangular Instance Array Opening the Part Open part file fmf2_instance_rectangular.prt from the fmf2 subdirectory, and start the Modeling application. This model was created with the Extruded Body option. You need to add holes to the top flange on the model.

Change to a Gray Thin Hidden Edges display.

Creating a Rectangular Instance Array Starting the Rectangular Array Choose the Instance Feature icon Instance.

, or choose Insert

Feature Operation

A dialog displays instance array options.

The Rectangular Array option lets you create a linear/rectangular array of instances from the selected feature(s). These arrays may be in either the XC, the YC, or the XC-YC direction.

1056 Choose the Rectangular Array option. Select the SIMPLE_HOLE(2) listed in the list box and OK the dialog.

Creating a Rectangular Instance Array Entering Parameters The Enter Parameters dialog displays.

Parameters for a Rectangular Instance Array

General creates an instance array from existing features and validates all geometry. An instance of a General array is allowed to cross an edge of the face. Also, instances in a General array can cross over from one face to another. Simple is similar to a General instance array, but it speeds up the instance array creation by eliminating excessive data validation and optimizing operations. Identical is the fastest way to create an instance array. It copies and translates all the faces and edges of the master feature. Each instance is an exact copy of the original. You can use this method when you have a great many instances, and you are sure they are all exactly the same. With an Identical array, no checking is done for invalid geometry. Number Along XC defines the total number of instances to be generated parallel to the XC axis of the WCS. This number includes the existing feature you are instancing. To create a one-dimensional array in the XC direction, set this value to one. XC Offset defines the spacing for the instances along the XC axis. This spacing is measured from a point on one instance to the same point on the next instance along the XC axis. Negative values position the instances in a negative direction along the axis.

1057 Number Along YC defines the number of instances to be generated parallel to the YC axis of the WCS. This number includes the existing feature you are instancing. To create a onedimensional array in the YC direction, set this value to one. YC Offset defines the spacing for the instances along the YC axis. This spacing is measured from one instance to the next along the YC axis. Negative values position the instances in a negative direction along the axis.

You will create 5 holes equally spaced in the XC direction. The part is 35 inches long, so you will space them 7 inches apart. You only need 1 row in the YC direction with a YC offset of 0 (zero). These parameters will create and space the holes seven inches apart along the top of the tray. Use the General method. Key in the following values: Number Along XC = 5, XC Offset = 7 , Number Along YC = 1 , and YC Offset = 0. OK the dialog.

Creating a Rectangular Instance Array Accepting the Array Temporary tool solids display in the graphics area.

A confirmation dialog displays Yes and No options.

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If you do not like the locations of these holes, you can choose No in the dialog, and respecify the number and spacing of the rectangular array. Because these holes are located where you need them, you can complete the instance array. Choose Yes. Cancel the dialog. The instance array is complete.

Close all part files.

Creating a Mirror Body Feature In this activity, you will mirror a solid body about a datum plane. Mirror Body lets you mirror an entire body about a datum plane. You can use this, for example, to form the other hand of a left hand or right hand part. When you use this option, the system creates a feature whose name is Mirror. This feature is time stamped and listed in the when you use Information Feature, just like other features. When you mirror a body, the Mirror feature is associative to the original body - it has no editable parameters of its own.

1059

Then, you will edit expressions and update the model and the mirrored body.

Creating a Mirror Body Feature Opening the Part File Open part file fmf2_instance_mirror_body.prt from the fmf2 subdirectory, and start the Modeling application.

Change to a Gray Thin Hidden Edges display.

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Creating a Mirror Body Feature Displaying the Datum Plane To mirror the body, you must use a datum plane. One is located on layer 5.

Choose the Layer Settings icon

or choose Format

Layer Settings.

Make the layer with the VERT-DATPL (datum plane) Selectable and OK the dialog. The datum plane displays in the view.

Creating a Mirror Body Feature Creating the Mirror Body Feature You will use the Mirror Body option to create the left half of this part like this.

Choose the Instance Feature icon

or Insert

Feature Operation

Instance.

The Mirror Body option mirrors the entire body about a datum plane to form the other hand of (as the left or right hand) a model.

1061 Choose Mirror Body. About Mirror Body Features

The following statements describe the Mirror body and its relationship to the original body and the datum plane. Any feature that you add to the master body after the mirror body feature is created will not be shown on the mirrored body. However, be sure that you do not reorder these features, such that they would occur before the Mirror feature. If you edit the parameters of the associated datum plane, the mirrored body changes accordingly. If you move the original body, the mirrored body also moves. The Class Selection dialog displays to help you select the bodies to mirror. If you choose the Type option on the dialog, you will be provided with two options to select from: Solid Body, and Sheet Body. Select the green solid body as the body to mirror, and OK the Class Selection dialog. You must select a datum plane to mirror the body. Select the datum plane as the object about which to mirror the body, and Fit the view. The mirror body is a separate solid.

If you delete the original body or datum plane associated with a mirrored body, the system deletes the mirrored body.

Creating a Mirror Body Feature Uniting the Two Solids There are now two solid bodies in your part file. Because these two solids will have coincidental faces at the datum plane, they can be united.

1062 You can combine the original and mirrored bodies using the Unite option to create a symmetrical model. When you unite these two bodies, you must select the master body as the target body, and the mirror body as the tool body. Otherwise the Unite operation will fail. This is also true for the Intersect and Subtract Boolean operations.

Choose the Unite icon

or Insert

Feature Operation

Unite.

The Unite dialog displays.

With the Target Body icon

With the Tool Body icon datum plane.

active, select the original solid body.

active, select the mirrored body on the other side of the

1063 Retain Tool saves the specified tool bodies for the unite operation. This option saves a copy of the tool bodies in an unmodified state. The option is not available when editing a Unite feature. Retain Target saves the target body for the unite operation. This option saves a copy of the target body in an unmodified state. If more than one tool body is selected, the boolean operation copies the target of the first boolean feature, but consumes the target bodies for the rest. The Retain Target option is not available when editing a Unite feature. You do not have to turn on the Retain Tool, Retain Target, and Confirm Upon Apply options. OK the Unite dialog.

Creating a Mirror Body Feature Modifying the Model Since the entire body is mirrored and associative, changes to a feature's parameters in the original body would be reflected in the mirrored copy. In this part, the extrusion was created from a sketch. If you edit the sketch dimension p10=10 that controls the height of the vertical face to p10=20, the sketch and solid will both update. Although the Expressions course covers expressions, you will edit this one expression value. Choose Tools

Expression.

The Edit Expression dialog displays. In the Edit Expression dialog, highlight the expression p10=10 in the list of expressions. In the value field beneath the list of expressions, change it to read p10=20 and press the Enter key on your keyboard, and OK the Expressions dialog. Both the mirror feature and the rectangular array of simple holes update.

1064

Close all part files.

Creating a Pattern Using Faces In this activity, you will create a rectangular instance of features by using the Pattern Faces Instance option. You can use Pattern Face when you have a set of faces, and you want to make a rectangular or circular pattern of them.

Creating a Pattern Using Faces Opening the Part Open the part file fmf2_pattern_faces.prt from the fmf2 subdirectory and start the Modeling application.

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You want to create a pattern of the rectangular pads, but the parameters have been removed from the part. The finished model will look like this.

Creating a Pattern Using Faces Creating a Rectangular Pattern

Choose the Instance icon

or Insert

Feature Operation

Instance.

The Instance dialog displays.

The Pattern Face instance option lets you create an array of a collection of faces. Choose the Pattern Face option on the Instance dialog. The Pattern Face dialog displays.

1066

Options on the Pattern Face Dialog

You can create a rectangular, or circular array, or a reflection of the pattern of faces. You will be creating a rectangular array of this pad on the non-parametric model. Choose the Rectangular Type icon. The Seed option

lets you specify one or more faces, as seed or target faces.

If you wish to pattern a region, select only one face to act as the seed face, and then use the Boundary selection step to specify the region. Pattern Face uses the same seed and boundary technique as that of Extract Region under the Extract Geometry option, except that you can select more than one seed face, and selection of boundaries is optional. Selecting more than one seed face in this step means they will all be treated as target faces by the system, and the pattern copy is applied equally across all of the faces. With the Seed selection step OK your selection.

active, select the top face of the pad as the seed face, and

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If you select no boundary faces, what you effectively have is multiple single selection. The faces you select must form a connected region. A boundary face can be of any type. No selected boundary face may be a selected seed face, and vice versa. With the Boundary selection step boundary face.

active, select the top face of the block as the

Creating a Pattern Using Faces Specifying the Number and Offset Values You want 5 pads in the X direction and 3 pads in the Y direction. You want the spacing to be 30 in the X direction and 26 in the Y direction.

Parameters for Offset Values

Number Along XC defines the total number of instances of the face set to be generated parallel to the X-Axis. This number includes the existing face set that you are copying. Used only with the Rectangular Type. Number Along YC defines the total number of instances of the face set to be generated parallel to the Y-Axis. This number includes the existing face set that you are copying. Used only with the Rectangular Type. XC Offset defines the spacing for the copies along the XC axis. This spacing is measured from a point on one copy to the same point on the next copy along the XC axis. Negative

1068 values position the copies in a negative direction along the axis. Used only with the Rectangular Type. YC Offset defines the spacing for the copies along the YC axis. This spacing is measured from a point on one copy to the same point on the next copy along the YC axis. Negative values position the copies in a negative direction along the axis. Used only with the Rectangular Type. Number is the total number of copies created in the circular pattern, including the existing face or face set that you are copying. Used only with the Circular Type. Angle is the angle between the copies in a circular pattern. Used only with the Circular Type. Preview Pattern Region lets you view the region to be copied by highlighting it before committing to the operation. For an extracted region this would show what is to be extracted, from the seed to the boundary. For target faces, this would show the faces to be copied. This special preview mode acts as a toggle, and is very useful in allowing you to experiment with the selection steps before initiating the operation. Reset cancels all face selections and restores the dialog settings to their initial state. Confirm Upon Apply opens the Confirm Upon Apply dialog after you choose Apply, letting you preview the results, and accept, reject or analyze them.

Key in these values for the pattern: Number along XC = 5, Number along YC = 3, XC Offset = 30, and YC Offset = 26.

Creating a Pattern Using Faces Specifying Rectangular Pattern Directions You need to specify the directions for the X axis and Y axis so that the system knows how to arrange the new pads. The X-Axis icon lets you define the X-Axis for the Rectangular and Circular types. You can use the Vector Method option menu to define the X-Axis, or select a reference for it from the graphics window. For the Rectangular Pattern Type, the X-Axis also defines the direction for the XC-Offset. For the Circular Pattern Type, the X-Axis defines the location for the central axis of the circular pattern. Choose the X-Axis selection step. Select the top front edge in its right half for the X-Axis. The direction vector should display like this.

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The Y-Axis option lets you define the Y-Axis for the Rectangular Type. You can use the Vector Method option menu to define the Y-Axis, or select a reference for it from the graphics window. The Y-Axis is used only with the Rectangular Pattern Type, and also defines the direction for the YC-Offset. Choose the Y-Axis selection step Axis.

and select the top left edge in its right half for the Y-

Another direction vector should display.

Creating a Pattern Using Faces Completing the Pattern Face Choose OK or Apply on the Pattern Face dialog. The model and pattern is complete.

1070

Close the part file.

Threads This lesson covers creating two types of Thread features on cylindrical faces: Detailed threads, and Symbolic threads.

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Creating Detailed Threads In this activity, you will create a detailed thread on the shaft of this pin.

Creating Detailed Threads Opening the Part Open part file fmf2_thread_detailed.prt from the fmf2 subdirectory, and start the Modeling application.

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Creating Detailed Threads Starting the Detailed Thread Choose theThread icon

or Insert

Feature Operation

Thread.

The Thread dialog displays. The Thread dialog lets you create symbolic or detailed threads (on solid bodies) that are right or left hand, external or internal, parametric, associative threads on cylindrical faces (such as holes, bosses, or cylinders.)

You can only add threads to an unthreaded cylindrical face. If the selected feature (with the cylindrical face) has been united to another body, the thread will start at the non-united end. If a cylindrical face has two planar (flat) ends that could be the start of the thread, your pick location will indicate the starting location and direction of the thread. If the cylindrical face has only one available planar end, it will be used as the start of the thread. If the cylindrical feature on which the threads are being added does not have a planar end, you must select a start face that is planar, such as a datum plane.

1073 Threads must be created from a planar starting face or datum plane. Since this cylinder has a planar end, you will not have to select a start location. Choose the Thread Type of Detailed on the dialog. The dialog updates for detailed thread creation.

Creating Detailed Threads Specifying Detailed Thread Parameters You can specify right hand or left hand threads. Use the Right Hand rotation. Select the cylindrical face of the pin. A direction vector displays the direction and a start location of the thread on the feature.

The Thread dialog displays default values for the detailed thread. These values are obtained from embedded tables for thread default parameters. The tables that are provided in the thd_english.dat and thd_metric.dat files are from one industry standard: Machinery's Handbook, 25th edition, 1996, published by Industrial Press Inc. There are other industry standards. You can modify these tables as required. You will change the length of the threaded portion of the pin. Change the Length value to 30, and use all other values. The detailed thread values are associative, so if you change the size of the feature, the thread will update. Choose OK to create the thread.

1074 You can see the threads more easily if the hidden edges are made invisible. Make the hidden edges invisible.

Close all part files.

Creating Symbolic Threads In this activity, you will create an Symbolic thread on the inside of the hole in this clamp.

Creating Symbolic Threads Opening the Part Open part file fmf2_thread_symbolic.prt from the fmf2 subdirectory, and start the Modeling application.

1075 A clamp displays in the view.

Creating Symbolic Threads Starting the Symbolic Thread Choose theThread icon

or Insert

Feature Operation

Thread.

Choose the Symbolic thread type. Symbolic threads are represented by dashed lines. They use external thread table files that you can customize to your specific thread requirements, and to determine default parameters. They can be created in multiple sets. They can be fully associative or created at a specified length.

Creating Symbolic Threads Selecting the Faces

You can select one or more cylindrical faces. The first face selected will set the default values.

1076 Unlike the pin, this simple through hole has two possible thread start locations. Your pick location will tell the system where you want the thread to start. Symbolic threads must start from a planar face or datum plane. Select the cylindrical face of the hole on the front face. A direction vector points into the hole from the front face.

The default thread values for this hole are displayed in the fields. You will use the defaults.

Creating Symbolic Threads Specifying Parameters

You can use the default tap drill size, or specify a different one. You can specify a different Tapped Drill Size, but use the default of 12.56792. Four manufacturing methods are available: Cut, Rolled, Ground, and Milled. Use the Cut method. Forms of threads available to you are: Unified, Metric, Trapezoidal, Acme, Stub Acme, Lowenherz, Buttress, Spark Plug, NPT, Hose Coupling, and Fire Hose. These methods are described in many engineering reference manuals on threads. Use Unified as the Form. You can create multiple thread starts, but you will only want one thread start for this hole. Use 1 for the number of thread starts.

1077 If you choose Full Thread, the thread will be associated to the length of the cylindrical feature. You will create a thread for the full length of the hole, so that if the hole changes, the thread will also change. Toggle Full Thread to on and notice that the Length field is now inactive. The Include Instances option is useful when you have an instance array that needs identical threads. You will not need to change this since there is only one hole. The Callout option references the thread table entry that provides the default values. If you use the Manual Input to specify parameters, the Callout field will gray out. The Choose from Table option lets you choose a different entry, and therefore a different set of default values. You will use the Right Hand Rotation, but you could choose to make the thread a Left Hand rotation. This hole has two possible starts, so you can specify a different starting location by using the Select Start option. You will not need to do this. Choose OK to create the internal symbolic thread. The symbolic thread is created and displayed as a dashed green circle at the start and end of the threaded length.

Close all part files.

1078

Scale Body This lesson covers using the Scale Body option to resize models for shrinkage or other design requirements. There are three types of scaling that you can perform: Uniform, Axisymmetric, and General. You will uniformly scale this model.

You will scale this model about the axis.

You will use the general scale option to scale this model.

1079

Uniformly Scaling a Model In this activity, you will use the Uniform scale icon to resize the model using one scale factor that is applied in all directions. This model has been built to finished size.

In this activity, you will scale the model larger so that a die can be developed that will allow for shrinkage of the molded product. You will use the Uniform Scale option to do this.

Uniformly Scaling a Model Opening the Part Open part file fmf2_scale_uniform.prt from the fmf2 subdirectory, and start the Modeling application.

1080

Uniformly Scaling a Model Starting the Uniform Scale

Choose the Scale Body icon

or Insert

Feature Operation

The Scale dialog displays.

You will uniformly scale the model about the WCS. Use the Uniform

type.

Scale.

1081

Uniformly Scaling a Model Specifying the Body to Scale There are four Selection Steps, which may be active depending on the Scale Type that you use. The Body selection step operation.

lets you select one or more solid or sheet bodies for the scale

You need to select the body to be scaled. With the Body

selection step active, select the solid body in the view.

OK the dialog.

Uniformly Scaling a Model Specifying a Reference Point

The Reference Point selection step icon scale operation is centered.

lets you specify a reference point from which the

The default reference point is the origin of the current WCS, though you can specify another using the Point Methods. This step is available only with the Uniform and Axisymmetric Types. Now, you can specify a point about which the scaling will occur. Check that the Reference Point icon is selected.

1082 The dialog now displays Point Method options that you can use to specify the reference point. You will scale the model about the arc center of the hole feature. Change the Point Method to Arc/Ellipse/Sphere Center. Select the edge of the largest hole feature. The system places a point at the arc center of the hole.

Uniformly Scaling a Model Specifying the Scale Factor To enlarge the model to allow for shrinkage, you will be scaling the model to 1.05 percent of its original size. For the Uniform type, there is a single Scale Factor parameter to enter, labeled Uniform. The value you enter is treated by the system as a base multiplier to apply to the scaling operation in all three X, Y, Z directions. Toggle on the Confirm Upon Apply option. Key in 1.05 in the Uniform Scale Factors field. Choose Apply on the dialog. A scale feature is temporarily created. The system applied a scale to the geometry of the body rather than to the independent features that comprise the body. OK on the dialog of confirmation options to complete the model.

1083

Cancel the Scale dialog. The scaled feature is associated to the original feature, so the scale factor and the scale origin can be edited. Close all part files.

Scaling a Model about an Axis In this activity, you will use the Axisymmetric scale option to scale a cylindrical body. The Axisymmetric scale lets you resize the model using two scale factors: one factor along a specified axis, and another scale in both directions perpendicular to the axis. In this activity, you will scale the model about the axis of the cylinder.

Scaling a Model about an Axis Starting the Model Open part file fmf2_scale_axis.prt from the fmf2 subdirectory, and start the Modeling application.

1084

Change to a wireframe view if necessary.

Scaling a Model about an Axis Starting the Axisymmetric Scale Feature

Because the shape of this model, (longer along the axis, and cylindrical in shape), you will scale the model about the axis of the cylinder.

Choose the Scale Body icon

or Insert

Feature Operation

Scale.

The Scale dialog displays. The Axisymmetric icon scales with a specified scale factor (or multiplier), symmetrically about a specified axis. This involves assigning one scaling factor along an axis you specify, and another, single scaling factor to be applied to the other two axis directions. Choose the Axisymmetric

scaling type.

Toggle off the Confirm Upon Apply option, if needed.

1085

Scaling a Model about an Axis Specifying the Body to Scale Three Selection Step icons are used for the axisymmetric method. The Body icon

lets you select one or more solid or sheet bodies for the scale operation.

This step is required for all three Type methods. The Reference Point icon lets you specify a reference point from which the scale operation is centered. The default reference point is the origin of the current WCS, though you can specify another using the Point Methods. This step is available only with the Uniform and Axisymmetric Types. The Reference Axis icon lets you specify a reference axis for the scale operation. The option is only available with the Axisymmetric Type method. The default is the WCS Z axis. You can change this using the Vector Methods. Choose the Body Selection Step icon. You need to select the bodies to scale.

1086 Select the model.

Scaling a Model about an Axis Specifying a Reference Point To control the scaling, you will set the reference point at the arc center of the hole in the shaft, and the reference axis along the YC axis. Choose the Reference Point icon. The Point Method becomes available to help you specify a fixed point for the scaling. Change the Point Method to Arc/Ellipse/Sphere Center. Select the edge of the hole feature. The system creates a point at the specified arc center location.

Scaling a Model about an Axis Specifying a Reference Axis and Scale Factors

1087

You need to specify the reference axis about which the scaling will occur. Choose the Reference Axis icon. The Vector Method options become available to help you specify the direction for the scale axis. Notice which axis displays along the direction of the cylindrical axis. Choose the YC Axis vector method. For the Axisymmetric type, there are two scale factor parameters: Along Axis and Other Directions. The Along Axis scale factor refers to the Reference Axis you specified in Selection Steps. The Other Directions scale factor refers to the other two axis directions. The values you enter are treated by the system as separate multipliers, one along the axis of the specified reference axis, and one to be applied to both of the remaining axis directions. You need to specify the scale factors along the YC Axis, and in all other directions. Change the scale factors so that Along Axis is set to 1.05, and Other Directions is set to 1.01. Choose OK to create the scaled feature. The model is scaled. Because the feature is only slightly larger than the original, you may not be able to see the model change. One way to verify the scaling is to check the distance from the front to the back of the shaft using the Analysis Distance option. Close all part files.

Scaling in Three Directions using a General Scale Type In this activity, you will use the General scale option to scale a model with specified scale factors in the X, Y, and Z directions.

1088

Scaling in Three Directions using a General Scale Type Opening the Part Open the part file fmf2_scale_general.prt from the fmf2 subdirectory, and start the Modeling application. In this model, the boss has been positioned using two datum planes, each centered on the block feature. The model has been hollowed, creating a thin walled solid body. The overall length of this model is 100 mm and the overall width is 75 mm. The design intent requires that the model be scaled in three directions: by 1.01 in the ZC direction, by 1.04 in the YC direction, and by 1.06 in the XC direction.

Scaling in Three Directions using a General Scale Type Starting the General Scale Feature

1089

Choose the Scale Body icon

or Insert

Feature Operation

Scale.

The Scale dialog displays. Toggle off the Confirm Upon Apply option, if needed. The General scaling type icon XC, YC, and ZC directions. Choose the General

scales the model based on the specified scale factors in the

scaling type.

Scaling in Three Directions using a General Scale Type Selecting the Body and CSYS Two selection steps (Body, and Reference Csys) are used for the General scale type. Body

lets you select the bodies to be scaled.

Use the Body Selection Step icon.

1090 You need to select the body to scale. Select the solid body in the view. You can specify the reference coordinate system for the general scaling. Choose the Reference CSYS icon. Choose the CSYS Method option on the dialog. When the Reference Csys selection step is active, CSYS Method becomes available. If you choose the CSYS Method option, a CSYS Constructor dialog displays, letting you specify a unique coordinate system. If no Reference Coordinate System is chosen or defined, the current Work Coordinate System will be used. Choose Back on the CSYS Constructor dialog. You will use the current work coordinate system, so no further selections are needed.

Scaling in Three Directions using a General Scale Type Specifying the Scale Factors You need to specify the scaling factors for the general scale. The design intent requires that the model be scaled in three directions: by 1.01 in the ZC direction, by 1.04 in the YC direction, and by 1.06 in the XC direction. Key in the Scale Factors for the X Direction as 1.06, the Y Direction as 1.04, and the Z Direction as 1.01. Choose OK on the dialog. The part is scaled. If you wish, check the dimensions of the part. Close all part files.

1091

Offset Face This lesson covers creating Offset Face features. Three Offset Face methods are: Offset Faces, Offset Features, and Offset Body. Offsets will fail if the resulting body would have a different number of faces than the parent body.

Offsets will fail also if self-intersecting conditions would result.

Offsetting a Face In this activity, you will offset faces of this model ...

1092 ... so that parts of the flange are thicker, like this.

Offsetting a Face Opening the Part Open the part file fmf2_offset_3.prt from the fmf2 subdirectory, and start the Modeling application.

Offsetting a Face Offset Requirements for this Model You need to offset this face of the wing rib in order to thicken it by half an inch.

First, you need to position the model for easier face selection. Rotate and Zoom in on the model so that it is oriented like this. Regenerate the view if needed.

1093

Offsetting a Face Starting the Offset Choose the Offset Face icon

or Insert

Feature Operation

Offset Face.

The Offset Face dialog displays.

You need to specify the offset that you want.

Offsetting a Face Specifying Parameters

The offset distance can be positive or negative, providing the topology of the body does not change. (If the topology would change, the system will report an error and will not create the offset.) For solid bodies, a positive offset distance is measured along a vector normal to the face pointing away from the solid. A negative offset is measured in the reverse direction. Key in an offset value of 0.50 OK the dialog. You need to select an offset type. Offset Faces lets you offset selected faces. Choose Offset Faces and select this face. You may need to rotate the view so you can select this face.

1094

Choose OK to complete the feature.

Cancel all dialogs.

Offsetting a Face Adding a Face to the Offset Feature

You can add other faces of the body to the offset feature. Double-click on the offset face to edit that feature. The Edit Parameters dialog displays editing options for this feature.

The view displays the current offset parameter.

1095 If you need to edit the offset value, you would click on the offset face expression in the view. The Add/Remove Offset Faces option lets you change the offset feature. Choose Add/Remove Offset Faces to add another face. You can now add or remove offset faces, by making your selections. Fit the view, and then zoom in on the left side. You need to add the similar face located on the other side of the model. The two methods to make selections are as follows: To add faces to the feature, simply select them. To remove faces, shift-select them. Select this face to add it to the offset feature.

Choose OK twice to complete the change.

Close all part files.

1096

Offsetting Adjacent Faces In this activity, you will offset the faces around the top of the pad to make the pad wider and longer, but not taller.

Offsetting Adjacent Faces Opening the Part Open part file fmf2_offset_1.prt from the fmf2 subdirectory, and start the Modeling application. Change to a Dashed Hidden Edges wireframe display.

1097

Offsetting Adjacent Faces Starting the Offset

Choose the Offset Face icon

or Insert

Feature Operation

Offset Face.

The Offset Face dialog displays. You will offset the outer faces of a rectangular pad on the model. Key in 0.125 as the Offset Value. Choose OK. The dialog displays options to offset faces, features, or bodies. Choose Offset Faces. You can select the first face for offset. For this activity, you need to offset the faces adjacent to the top face of the shorter rectangular pad. This will keep the pad the same height, but make it larger in length and width. Choose All Adjacent to Face. Select this face.

Choose OK. The system highlights the faces that are adjacent to the face you selected, and that will be offset. You could continue face selection. Choose OK to complete the offset. Cancel the dialog. Close all part files.

1098

Offsetting a Feature In this activity, you will offset a hole using a negative value, thus making the hole feature larger.

Offsetting a Feature Opening the Part Open part file fmf2_offset_1.prt from the fmf2 subdirectory, and start the Modeling application. Change to a Dashed Hidden Edges wireframe display.

1099

Offsetting a Feature Starting the Offset Choose the Offset Face icon

or Insert

Feature Operation

Offset Face.

This time, you will use a negative value. Remember, positive offset direction is away from the solid, and a negative offset direction is into the solid. Key in -0.125 as the Offset Value. Choose OK. A dialog displays Offset Faces, Offset Features, and Offset Bodies. Choose Offset Features as the offset selection type. You can select the features to offset. Many features can be selected at one time, but you will only need to offset the simple hole feature. Choose SIMPLE_HOLE(3) from the dialog. The system highlights the faces that will be offset.

Choose OK on the dialog. The hole is enlarged, because the offset was negative. If you had used a positive value, the hole would be smaller.

1100

Cancel the dialog. Close the part file.

Offsetting Features in an Instance Array In this activity, you will offset a feature, thus enlarging the size of one of the rectangular holes in the model.

Offsetting Features in an Instance Array Opening the Part Open part file fmf2_offset_2.prt from the fmf2 subdirectory, and start the Modeling application.

1101

Change to a wireframe display.

Offsetting Features in an Instance Array Starting the Offset You will be enlarging one rectangular pocket in the instance array. Zoom in on this part of the model and change to a wireframe view.

Choose the Offset Face icon

or Insert

Feature Operation

Offset Face.

Offsetting Features in an Instance Array Selecting the Feature to Offset Since these rectangular pocket features are small, you need to use a small enough offset so that resulting body will not have self-intersecting faces, and will not have a different number of faces.

1102 Key in -0.01 as the Offset Value, and choose OK. You will offset one member of an instance array. When offsetting a member of an instance array, only the selected instance will be offset. The entire instance array will not receive the offset. Also, you cannot instance an offset feature. Therefore, if you want to offset all members of an instance array, you must create the offset feature for each member of the instance array. Choose Offset Features. Choose INSTANCE[0] (17) / RECTANGULAR_POCKET (17) feature on the dialog, or select the feature in the view. The rectangular pocket highlights in the view.

The system highlights the feature that will be offset. Choose OK. Cancel all dialogs. The model now has a slightly larger rectangular hole at this location.

Close all part files.

1103

Offsetting a Body

In this activity, you will offset the faces of the entire body, like this.

Offsetting a Body Starting the Model Open the part file fmf2_offset_3.prt from the fmf2 subdirectory, and start the Modeling application.

Offsetting a Body Starting the Offset Choose the Offset Face icon

or Insert

You need to specify the offset that you want.

Feature Operation

Offset Face.

1104 Key in an offset value of 1.0 and choose OK. Choose Offset Body. Select the solid body to complete the offset.

Cancel the dialog. Close all part files.

Sew This lesson covers using the Sew option to join bodies. The option can be used in some cases where the Unite option would fail. Solids can be sewn to solids, and sheets can be sewn to sheets. You will sew sheets, and also sew solids.

1105

You can edit sewn sheets by using Edit Feature Parameters, and selecting the sew feature.

Sewing Sheet Bodies In this activity, you will sew nine sheet bodies into one sheet body.

Sewing Sheet Bodies Opening the Part Open part file fmf2_sew_sheets.prt from the fmf2 subdirectory, and start the Modeling application.

1106

Two of the features have been created with Through Curve Mesh, a feature that is covered in the Free Form Modeling course. Other features in the part are unparameterized, but you will still be able to sew the sheet bodies together.

Sewing Sheet Bodies Starting the Feature

Choose the Sew icon

or Insert

Feature Operation

Sew.

The Sew dialog displays. You will be sewing sheets, so choose Sheet as the Sew Input Type. The sheets in this part file can be sewn using the default tolerance values, but if you were working on other parts with larger gaps than this default tolerance, you would have to increase the tolerance value. Use the default Sew Tolerance.

Sewing Sheet Bodies Specifying the Target and Tool Sheets You will use the center cyan sheet body as the target sheet body. With the Target Sheet selection step sheet.

active, select the cyan sheet body as the target

1107

Choose the Tool Sheets selection step. You need to select the tool sheets. Select all of the 8 sheets around the target sheet.

Choose OK to complete the feature. The sheets are sewn into one sheet body.

Close the part file.

Sewing Two Solid Bodies

In this activity, you will sew two solid bodies.

1108

Sewing Two Solid Bodies Opening the Part Open part file fmf2_sew_solids.prt from the fmf2 subdirectory, and start the Modeling application. Two solids exist: a yellow solid, and a green solid.

Sewing Two Solid Bodies Starting the Feature

1109

Choose the Sew icon

or Insert

Feature Operation

Sew.

The Sew dialog displays. The Sew option lets you join two or more solids, if they share coincident faces. Because these two solids have coincident faces, you can sew these two bodies into one. Change the Sew Input Type to Solid. These solids can be sewn using the default tolerance values, but if you were working on other parts with larger gaps, you might have to increase the tolerance value. Use the default Sew Tolerance. Since there are no instances in this part file, you can toggle the Sew All Instances to off. Toggle Sew All Instances to off.

Sewing Two Solid Bodies Blanking Objects You need to select the target faces first. The Target Faces selection step is active. To make the target face selection easier, you can blank the small solid body. Choose Edit

Blank

Blank.

A Class Selection dialog displays to help you filter your selections, but you will just select the solid body in the view. Select and accept the yellow body and choose OK.

1110

Sewing Two Solid Bodies Selecting Target Faces

Now, you can select the target faces to sew. As you select the target and tool faces, the area values on the Sew dialog will change from zero to that area selected. You need to select the target faces. Select these three inside faces, that are adjacent to the faces of the small solid body that you just blanked.

You have completed selection of the target faces.

1111 On the Sew dialog, the total area of the target faces that you selected is displayed. The Target Area should be approximately 58.67.

Sewing Two Solid Bodies Reverse Blanking Objects Before you select the tool faces, you need to reverse blank the part. Choose Edit

Blank

Reverse Blank All.

The prior blanked solid is unblanked, and the prior unblanked solid is blanked. This will make face selection easier for you.

Sewing Two Solid Bodies Selecting Tool Faces

Choose the Tool Faces icon. You can now select the tool faces. Select the three vertical faces that are adjacent to the faces of the larger body.

1112 The Target Area and Tool Area options in the Sew dialog now displayed the area of all selected faces. The Area values are very close. If the values are quite different, then the system will not be able to sew the faces. Before you complete the sew operation, you will want to unblank all of the part file so that the model will be visible after the sewing is complete. Whenever objects are blanked, you can easily make all objects unblanked by using the Unblank All of Part option. Choose Edit

Blank

Unblank All of Part.

Continue with the sew operation. Choose OK on the Sew dialog. The two solids have been sewn into one body. The tool body inherits the color of the target body.

Close all part files.

1113

Extract Geometry

This lesson covers using the Extract Geometry option. The Extract Geometry option lets you create associative copies of curves, faces, or bodies. You will be creating the following types of extracted geometry. Extracted curves

Extracted faces

Extracted region

1114

Extracted body.

Extracting Curves In this activity, you will extract the four edge curves shown in green.

Extracting Curves Opening the Part Open part file fmf2_extract_curves.prt from the fmf2 subdirectory, and start the Modeling application.

1115

Change to a wireframe Gray Thin Hidden Edges display.

Extracting Curves Starting the Feature Choose the Extract Geometry icon

or Insert

Form Feature

Extract.

Extracted curves are features, and will display in the Model Navigator window. These feature curves are associative. The Extract dialog displays.

1116

Extracting Curves Selecting the Edges for Extracted Curves

The Curve icon

is highlighted on the dialog.

You can select the curves to extract. If you choose another one of the four icons at the top of the dialog, the contents of the dialog will change as needed. Zoom in on the top of the body and select these four outer edges of the model.

Extracted curve feature(s) are always created at the time stamp. Choose OK on the Extract dialog. Regenerate the work view.

The extracted curve feature is not the same as the curve object that you can create using Insert Curve Operation Extract. The extracted curve feature is edited using the Edit Feature option; whereas, a curve object is edited using the Edit Curve options.

1117

Extracting Curves Associativity of the Extracted Curves and the Block Feature Extracted curve features display in the Model Navigator window as features, and have system names. Extracted curve features are associated with the model. In this part, if you edit the block parameters, the extracted curve features update. But, adding another feature to the block (such as a taper or blend) will not result in a change to the extracted curves.

Choose the Edit Feature Parameters icon , or choose Edit Parameters, select the BLOCK(0) feature, and choose OK.

Feature

Choose Feature Dialog on the dialog. On the Edit Parameters dialog, change the X Length of the block to 10.0 and choose OK several times. Fit the view. The model and extracted curves update.

Close the part file.

Extracting Faces In this activity, you will extract the inside bottom face of the model and extrude the extracted face into a solid body.

1118

Extracting Faces Opening the Part Open part file fmf2_extract_faces.prt from the fmf2 subdirectory, and start the Modeling application.

Extracted faces are sheets; so, you need to change the work layer to one that has a category of sheet bodies. Change the Work Layer to layer 81 and change to a wireframe display. Change to a wireframe Gray Thin Hidden Edges display.

Extracting Faces Starting the Extracted Face Choose the Extract Geometry icon

or Insert

To extract faces you need to use the Face icon. Choose the Face icon.

Form Feature

Extract.

1119 The Extract dialog changes to include options for extracting faces.

The extraction of faces is useful for converting sheet body types to B-Surface types, so their data can be transferred to other integrated systems. At Timestamp should be toggled off. Blank Original should be toggled off. Every face has an underlying surface type. Examples of surface types include trimmed or nontrimmed planar surfaces, cylindrical, blending, toroidal, B-Surface, spherical, and many more. The Type of Resulting Surface options include: Same Type Surface converts the selected faces into sheets, maintaining the original surface type. Polynomial Cubic converts the selected faces to polynomial cubic (degree of three) B-Surface sheets. This option usually approximates the original faces, so they may not be replicated exactly. This type of sheet is an array of parametric cubic patches that can be exported to almost all other CAD, CAM, and CAE applications. General B-Surface converts the selected faces to more general B-Surface types. The resulting sheets may be rational (rather than polynomial), and they may not be cubic (degree of 3). The resulting B-Surface type sheets are more likely to exactly replicate the original faces, but are more difficult to transfer to other systems. You can use Same Type Surface for the extracted face.

1120

Extracting Faces Selecting Faces Selection options let you select specific faces, using Selected Face, or Adjacent to Face, or All in Body. You can also select faces by a name. Use Selected Face to select individual faces. You will not be deleting holes. Check that Delete Holes option is toggled off. Select this face.

Choose Apply on the Extract dialog. Regenerate the view, if needed to update the display.

Extracting Faces Extruding the Extracted Face into a Solid The new sheet is displayed in white. You can extrude the new feature into a solid. To make selection easier, you can blank the solid. Choose Edit Blank Blank, choose Type, choose Solid Body, choose OK, choose Select All, and choose OK. Refresh or Regenerate the view. These steps are minimal, since Extruded Body features were covered in an earlier lesson. Make Layer 2 the work layer, so that the new solid body is on a layer for solid bodies. Choose the Extruded Body icon

or Insert

Form Feature

Extrude.

1121 Choose Sheet Body, select the sheet, and choose OK. Choose Direction & Distance, and choose OK to accept the default direction. Set the values to 0, 1, 0, 0, 0, and choose OK. Choose Create and Cancel all dialogs. The new solid displays.

Extracting Faces Associativity of Extracted Face Features Choose Edit

Blank

Unblank All of Part.

Shade the model to see both solids. The extruded body is associated with the other solid in the part file.

Extracted faces are associated with the solid body on which they were developed. If you move the pad feature in the middle of the green body, the extracted face and the extruded body will both update. Choose Format

Layer Settings and make layer 65, and 62 Selectable.

1122

Choose the Edit Feature Parameters icon

or Edit

Feature

Parameters.

Choose DATUM_PLANE(33) and choose OK. Change the Offset value from 20 to 30 and choose OK. Choose OK on the dialog. Because of the associative relationships that exist in this part file, both solid bodies update.

Close the part file.

Extracting a Region of a Body In this activity, you will extract the inner faces of the model to create the extracted region sheet body shown in the lower view on the graphics window.

1123

Extracting a Region of a Body Opening the Part Open part file fmf2_extract_region.prt from the fmf2 subdirectory, and start the Modeling application.

Extracting a Region of a Body Starting the Feature

Choose the Extract Geometry icon

or Insert

Form Feature

Extract.

The Region option lets you create a single sheet body composed of a collection of faces that are related to a "seed face" and limited by "boundary faces". Choose the Region icon

on the dialog.

The dialog changes as needed to extract a region of a model. You need to select the seed face for the region.

1124

The Seed Face icon

is active.

The system uses the Seed Face that you select as a starting location to collect all faces for the extracted region. This is the only seed face that you need to select. Select the bottom inside face as the Seed Face. (Zoom in, if needed.)

The Tangential Edge Angle option, and the Angle Tolerance in degrees can be used to limit faces that are included in the feature as the system "walks away" from the seed face. The option is toggled off by default. When toggled on, the default angle is 45 degrees. Modifications to the angle will be remembered during the current session.

1125 If the normals of two faces that meet along the edge (one face included in the region, the other its neighbor) exceed the angle given by the user, then the neighbor face is not added. This option also allows the selection of boundary faces to become optional.

Extracting a Region of a Body Specifying the Boundary Faces and Previewing a Region

Now you need to specify the boundary faces. Choose the Boundary Faces icon. The system uses the Boundary Faces that you select to limit the collection of faces, thus the boundary face(s) identifies the boundary of the extracted region. You can select many faces for boundary faces. Select this face as the boundary face.

Fit the views.

Extracting a Region of a Body Previewing the Region

You can use the Preview Region option to check that you are satisfied with the region that will be extracted, based on your selections to this point. Choose Preview Region, so that you can check what region is currently defined. The display indicates the region that will be used to create the extracted region feature.

1126

You need to include the posts, but not include the holes located in the posts, so you must make some additional selections. Choose the Finished Preview option so that you can continue to make selections.

Extracting a Region of a Body Traversing Interior Edges

The Traverse Interior Edges option lets the system collect those faces whose edges form part or all of any interior loops, such as the posts. Toggle on the Traverse Interior Edges option. Choose Preview Region to see what is selected now. All interior faces highlight, including the posts. If you create the extracted region sheet body now, the faces of all holes will be included in the extracted region sheet body. Choose the Finished Preview option so that you can continue to make selections.

Extracting a Region of a Body Selecting More Boundary Faces You do not need include the holes in the posts. To close them off, you can specify additional boundary faces. The faces inside the four holes must be selected as additional boundary faces. Otherwise, the system continues "collecting faces" through the holes and on to the boundary that you use.

1127 Use Zoom and Pan to enlarge your view as needed for each boundary face selection. Select the upper inside face of each countersunk hole.

After all four boundary faces are selected, your view should look like this.

Extracting a Region of a Body Deleting All Openings If you leave the Delete All Openings option toggled off, any openings in the collected faces will remain. You need to close the openings where the countersunk holes exist. An "opening" is any interior loop that has faces only on one side of all edges in the loop. Toggle on the Delete All Openings option. Choose Preview Region to see the faces selected at this point. The collection of faces is ok.

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Choose Finished Preview to continue.

Extracting a Region of a Body Blanking the Original If the Blank Original option is toggled on, the original body will be blanked after the extracted region is complete. You do not need to use the Blank Original option because this part file has been set up so that the upper view contains the model, and the lower view contains the extracted region sheet body. Leave the Blank Original toggled off. After you identify the seed face, all boundary face(s), and specify all desired options, the system finds all faces from the seed face to the boundary face(s). From this set of faces, a single sheet body, called an Extract Region feature, is created. Choose Confirm Upon Apply, so that when you see the finished model, you will have an opportunity to decide how to process the results. Extracting a Region of a Body Using the At Timestamp Option

When At Timestamp is toggled on, subsequently created features added to the solid model will not be reflected in the extracted region body. Whereas, if At Timestamp is toggled off, subsequently created features added to the solid model will be reflected in the extracted region sheet body. So, you will typically leave this toggled off. Leave the At Timestamp option toggled off. Choose Apply.

1129 Fit both views. The new sheet body displays in the lower view. Choose Accept Result. Cancel the Extract dialog. The extracted sheet body is complete.

Close all part files.

Extracting an Entire Body In this activity, you will create an extracted body.

1130

Extracting an Entire Body Opening the Part Open part file fmf2_extract_body.prt from the fmf2 subdirectory, and start the Modeling application.

If you extract a body, the new body will be the same type (solid or sheet) as the original.

Extracting an Entire Body Setting up a Custom Two View Layout Before you create the extract_body, you will set up a two view layout and set the visibility so that you only see the layer 1 in the TFR-TRI view, and layer 2 in the TFR-TRI#1 view. This way, the original solid will display in the upper part of the graphics area, and the extracted body in the lower part.

1131 Choose Format

Layout

Open.

Choose L3 - upper and lower and then choose OK. The default layout is a top view and a front view. You need to change both views to a TFR-TRI view. In the upper view, press MB3, and choose Replace View In the lower press MB3, and choose Replace View

TFR-TRI to change the view.

TFR-TRI to change the view.

Notice that the lower view name is TFR-TRI#1, because you cannot have two views with the same name. In each view, choose MB3

Hidden Edges

Dashed.

You need to save this layout with a different name. Format

Layout

Save As, key in 2VIEW_TFR, and choose OK.

Extracting an Entire Body Setting up the Visibility in Each View You need to change the visibility in each view, so that the original solid will display in the TFR-TRI view, and the extract_body will display in the TFR-TRI#1 view. You need to set visibility to each view separately. The solid body is currently on layer 1. You will make only layer 1 visible in the TFR-TRI view.

1132 Choose Format

Visible in View.

The Visible Layers in View dialog displays. In the dialog, choose TFR-TRI and choose OK. The Visible Layers in View dialog changes. Choose ALL in the dialog. Choose Invisible. Choose 1 in the Layer and Pending Status list box, and choose Visible, and OK. You will create the extracted body on layer two, so you will make only layer 2 (currently an empty layer) visible in the TFR-TRI#1 view. Click on TFR-TRI#1 in the Visible Layers in View dialog, and choose OK. Choose ALL in the Visible Layers in View dialog. Choose Invisible. Choose 2 in the Layer and Pending Status list box, choose Visible, and choose OK. Choose Cancel on the Visible Layers in View dialog. The lower view does not display any geometry, because layer 2 is empty. (You can check this if you want, by choosing Format Layer Settings, choosing Layers with Objects, toggling on Show Object Count, and choosing Apply.) You need to save the layout with the visibility in view settings complete. Choose Format

Layout

Save.

Extracting an Entire Body Extracting the Body You need to place the extracted body on layer two. Make layer 2 the Work Layer. Choose the Extract Geometry icon

or Insert

Form Feature

Extract.

The Body icon creates an associative copy of an entire body. The new body will be the same type (solid or sheet) as the original.

1133

Choose the Body icon. When At Timestamp is off, the EXTRACT_BODY will include features that you add to the original body after the extract body feature is created. When At Timestamp is on, the features you add to the original body will exist in the EXTRACT_BODY after the extract body feature is created. Toggle At Timestamp to on. Blank Original automatically blanks the original body after the selected sheet is converted, but does not delete it. Use Edit Blank Unblank to return the original sheet to the screen. Blank Original has no effect when the selected objects are faces from a solid or sheet body, only for single face sheets. Because the new body will be created in a separate view from the rest of the model, you will not need to blank the solid. The Blank Original should be toggled off. Select the body to extract, and choose OK. The extracted body displays in the lower view, and this extracted body is on layer 2. Because the object color default is set to green, the new extract body feature displays in green.

Extracting an Entire Body Adding a Hole to the Original Body Choose the Hole icon

or Insert

Form Feature

Hole.

Use the Simple hole type. Select and accept the top face of the pad as the placement face.

1134

Select the bottom face as the through face. Key in a diameter of 14.0 and choose OK.

Extracting an Entire Body Positioning the Simple Through Hole Now, you can specify a positioning dimension. Choose Point onto Point

as the positioning method.

In the upper part of the graphics area, select this edge.

Choose Arc Center. Because the At Timestamp was on, the hole is part of the original solid model, but not part of the extract_body solid.

1135

One use for an extract Body feature is when you want to have an original solid and a simplification available at the same time (e.g., to place in separate reference sets, which are covered in the Assembly Modeling course).

Extracting an Entire Body Adding a Hole to the Extracted Body Create a simple thru hole at the other end of the pad on the body in the lower view. (Refer to the earlier steps, if you need to.) You should see two different solid bodies like this.

Close all part files.

1136

Sheet From Curves This lesson covers creating Sheets From Curves. Sheets from Curves are unparameterized, and non-associative, so edits to these can be more difficult. Sheets From Curves does not create spherical sections. Before using this option, you must create sheets at all sections of spheres. This option also does not create typical ruled sheets.

The Sheets From Curves option

lets you create bodies through selected curves.

Sheets From Curves creates the following bodies: Bounded planes, by forming planar closed loops (using the ends of curves) (Single planar loops must be periodic), Cylinders, by pairing circles and ellipses with coaxial centers, Cones, by pairing arcs with coaxial centers, and Extruded, bodies by pairing conics and planar splines.

Creating a Cylinder from Two Circles In this activity, you will create three sheets from these two curves: one for each of the two circles, and one between the two curves.

1137

Creating a Cylinder from Two Circles Opening the Part Open part file fmf2_fromcurves_circles.prt from the fmf2 subdirectory, and start the Modeling application. Two curves display.

Creating a Cylinder from Two Circles Starting the Sheets from Curves

The Sheet from Curves option

lets you create unparameterized sheet bodies from curves.

Choose the Sheet from Curves icon Curves.

or Insert

Form Feature

Sheet from

The dialog display provides you two options. The Cycle By Layer option causes the system to process all selectable curves one layer at a time, thus reducing processing time. Toggle on the Cycle By Layer option to reduce processing time. Setting the Warnings option to on causes the system to stop processing, and to display warning messages after generating bodies if there are any warnings. You will be warned about non-closed planar loops of curves, and about non-planar boundaries. If the option is toggled off, you will not be warned, and processing does not stop. Toggle on the Warnings. Choose OK.

1138

Creating a Cylinder from Two Circles Selecting the Curves

The Class Selection dialog displays, but you are limited to selecting curves, or a named group of curves. Both circles are coaxial, parallel, and have the same radius value, which are requirements for creating sheets from curves. Select both curves, and choose OK on the Class Selection dialog.

The cylindrical sheet is unparameterized, and the circles surround the other two unparameterized sheets. Close the part file.

Creating a Cone from Curves In this activity, you will create three sheets using the two arcs.

1139

Creating a Cone from Curves Opening the Part Open the fmf2_fromcurves_circles.prt part file from the fmf2 subdirectory, and start the Modeling application. Make layer 2 the Work Layer, layer 1 and 41 Invisible, and layer 42 Selectable. Fit the view.

Creating a Cone from Curves Starting the Sheets from Curves

Choose the Sheet from Curves icon Curves.

or Insert

Form Feature

Sheet from

Check that both Cycle by Layer and Warnings options are toggled on. Choose OK. You can select two coaxial arcs with different radius values to create a conical sheet. You must use arcs (not ellipses) to generate sheets. The system always generates truncated (non-pointed) conical sheets. Select both curves. Choose OK on the Class Selection dialog. The truncated conical sheet and two planar sheets are created. You cannot use the Sheets from Curves icon, and then select a point and a circle to create a cone.

1140

Close all part files.

Creating a Bounded Plane from Curves In this activity, you will create a bounded plane sheet body from the curves in the view.

Creating a Bounded Plane from Curves Opening the Part Open part file fmf2_fromcurves_bnd_pln.prt from the fmf2 subdirectory, and start the Modeling application. Lines and arcs that are on layer 1. The work layer is 81, which has a category of "sheets".

1141

Creating a Bounded Plane from Curves Starting the Sheet

Choose the Sheet from Curves icon Curves.

or Insert

Form Feature

Sheet from

Check that Cycle by Layer and Warnings options are toggled on. Choose OK. The cyan curves are in a sketch, the orange circle and yellow lines are regular curves. All curves are coplanar, and each string of curves forms a closed loop, both of which are requirements for creating a bounded plane. Select all curves and choose OK on the Class Selection dialog. The unparameterized bounded plane is created. The outer boundary curves specify the perimeter of the plane. The inner boundary curves specify the holes in the bounded plane.

The U-V grid that you see is controlled by the Modeling Preferences. Close all part files.

1142

Creating an Extruded-Like Body from Splines In this activity, you will use two closed coplanar splines to create an unparameterized sheet body that is somewhat similar to an extruded sheet body, and two planar sheets.

Creating an Extruded-Like Body from Splines Opening the Part Open part file fmf2_fromcurves_splines.prt from the fmf2 subdirectory, and start the Modeling application. Two identical, closed splines display. Identical splines, parabolas, ellipses, hyperbolas can form an extruded-like sheet body.

Creating an Extruded-Like Body from Splines Starting the Sheets The splines, to be used for the Sheets from Curves features, must be on parallel planes and one must project onto the other. The curves in this part file meet the requirements stated above.

1143

Choose the Sheet from Curves icon Curves.

or Insert

Form Feature

Sheet from

Check that the Cycle by Layer and Warnings options are toggled on. Choose OK. Select both splines, and choose OK on the Class Selection dialog. Unparameterized sheet bodies are created.

Close all part files.

Split Body This lesson covers creating a Split Body feature. The Split Body icon lets you divide target bodies using a face, datum plane, or other geometry.

Splitting a Solid Body with a Face

1144

In this activity, you will split the solid body using the sheet body.

Splitting a Solid Body with a Face Opening the Part Open part file fmf2_splitbody.prt from the fmf2 subdirectory, and start the Modeling application. A solid body and sheet body exist in the part file.

Splitting a Solid Body with a Face Split Body Warnings

Choose the Split Body icon

or Insert

Feature Operation

Split.

1145 A Split Body message displays to warn you that this operation removes parameters, and that drafting information in section views will also be lost.

Choose OK, to continue to split the body.

Splitting a Solid Body with a Face Specifying Target Bodies and a Splitting Object You must select the target bodies to be split. Select the solid target body and choose OK.

Next, you can select the face or datum plane that you want to use to split the bodies. The Split Body dialog displays a list of splitting objects.

Split Body Dialog Options

You can split a target by selecting an existing face or datum plane, or by using one of the options on the Split Body dialog. If you use Define Plane, a plane subfunction dialog displays methods that let you define a plane for the split.

1146 If you use Define Cylinder, you are permitted to define the cylinder with a diameter and origin, or select an arc/circle to define the cylinder. If you use Define Sphere, you are permitted to define the sphere with a center and diameter, or by selecting a great circle. If you use Define Cone, you are permitted to specify two coaxial arcs of the cone, specify two diameters and a height, or specify a diameter and half angle. If you use Define Torus, you are permitted to specify a major radius, minor radius, and a toroidal axis. When you split a body using a face of another body, the face must be large enough to cut through the target body completely.

Select the sheet body, to split the target body.

Splitting a Solid Body with a Face Checking the Model A message displays that parameters have been deleted from resulting bodies. OK the message. The single solid body has been split into two solids.

Cancel the Split Body dialog. Close all part files.

1147

Patch Body This lesson covers creating a Patch Body feature. The Patch Body option is useful when: Small gaps or small mismatches in surface normals between tool and target bodies might cause other operations, such as Trim Body or Split Body, to fail. You want to apply a hand shaped blend. You want to create a hole with a more complex shape than those available from the Hole feature menu.

Creating a Spherical Patch on a Sheet Body In this activity, you will create this sheet body in three steps: Trim the spherical sheet body with the rectangular sheet body. Patch the rectangular sheet body. Blend the edge at the location of the spherical surface and sheet body.

1148

Creating a Spherical Patch on a Sheet Body Opening the Part Open part file fmf2_patch_1.prt from the fmf2 subdirectory, and start the Modeling application. The part file contains many blanked objects on layer one. These include points, sheet bodies, and more. You need to work with the two sheet bodies that are displayed.

Creating a Spherical Patch on a Sheet Body Trimming the Spherical Body Before you create the patch, you must trim the spherical body to the face of the rectangular sheet. These steps are brief, since trim body was covered in an earlier lesson. Trimming is necessary here, because the distance between the edge of the tool body (part of the sphere) and the face of the target body (the free form sheet) must be within the Modeling Distance Tolerance.

Choose the Trim Body icon

or Insert

Feature Operation

Trim.

Select and confirm the spherical body as the target body. Choose OK on the Trim Body dialog. Select the approximately rectangular sheet body as the trim body. A direction vector displays the ZC direction in which the trim will occur.

1149

You need to reverse the direction vector, so that the lower portion of the spherical body is removed. The sheet will not be changed. Choose Reverse Default Direction so that the bottom portion of the sphere will be trimmed.

Cancel the dialog.

Creating a Spherical Patch on a Sheet Body Creating the Patch Body Now, you will patch (to join) these two sheets together.

Patch Body

lets you join a different shape sheet body to existing sheet or solid bodies.

Choose the Patch Body icon

or Insert

Feature Operation

Patch.

1150 The Patch dialog displays.

Creating a Spherical Patch on a Sheet Body Specifying the Target and Tool Bodies You need to select a target body, which will receive the patch. The Confirm Upon Apply option lets you view and confirm/reject the feature before you create it. The Confirm Upon Apply can be toggled off. The Target Body icon

is active. The target body is the body to be modified.

Select the roughly rectangular sheet as the target body. The Tool Sheet icon target body.

is active. The tool sheet is the sheet which will be patched onto the

The Tool Face is the used if you want to patch only a single face of a sheet with multiple faces for patching. Select the trimmed spherical sheet body as the tool body. A direction vector displays pointing normal and away from the spherical body. To remove the area under the spherical bump, you need to reverse the vector. Choose Reverse Removal Direction. The direction vector is reversed.

1151

Choose Apply to complete the patch operation.

Creating a Spherical Patch on a Sheet Body Blending an Edge on the Patched Body Now, you can blend the edge where the bump is located on the flatter sheet. These steps are brief, since blending was covered in an earlier lesson.

Choose the Edge Blend icon

or Insert

Feature Operation

Edge Blend.

Select the edge where the spherical shape contacts the rectangular shape. Change the Default Radius to 20, and choose OK to complete the model.

Close all part files.

Using Patch Body to Create an Irregular Hole in a Solid Body In this activity, you will create an irregular hole in the solid block, by patching the sheet body that defines the shape of the hole into the solid body.

1152

This hole can also be created with the Trim Body option.

Using Patch Body to Create an Irregular Hole in a Solid Body Opening the Part Open part file fmf2_patch_2.prt from the fmf2 subdirectory, and start the Modeling application.

Using Patch Body to Create an Irregular Hole in a Solid Body Specifying the Hole Patch, Target Body, and Tool Sheet One requirement for patch body is that the edges of the tool sheet body must lie within the modeling distance tolerance of the faces of the target solid body. This condition is met in this part file.

Choose the Patch Body icon

or Insert

Feature Operation

Patch.

The Create Hole Patch option on the Patch Body dialog lets you create a hole, by patching in a sheet body.

1153 This is useful if you need special shaped holes that cannot be created using the Hole feature. Toggle on the Create Hole Patch option. Toggle off the Confirm Upon Apply option, if needed. Select the block as the target body to patch. Select the ruled sheet body, which passes through the solid, as the tool sheet to patch. Choose Apply. The block has been patched with the sheet body feature, creating an elliptical shaped hole. Cancel the Patch Body dialog. Shade the model.

Close all part files.

Editing a Patch Body In this activity, you will create a patch body feature. Then, after noticing undesirable surface indentations, you will edit the parameters of the patch feature, change the tool sheet, and update the model.

1154

Editing a Patch Body Opening the Part Open the part file fmf2_patch_4.prt from the fmf2 subdirectory, and start the Modeling application.

Editing a Patch Body Creating the Initial Patch Body Feature

A sheet body has been created to blend the top close edge of the part. You can begin by patching it into the solid.

Choose the Patch Body icon

or Insert

Feature Operation

Patch.

Select the solid body as the target body. Select the sheet body as the tool. Make sure the removal direction arrow is pointing upward. Choose OK until the model is complete. The model now has been patched.

If you shade the model, you will notice a deep indentation along the curved face.

1155

Editing a Patch Body Changing the Sheet Used in a Patch Body The design indent requires that the curved surface be smoothed out, so you need to change the patched face. An alternate design for the blend has been created and is located on layer 2. Make layer 2 Selectable to see the new sheet body that you will use.

Choose the Edit Feature Parameters icon

or Edit

Feature

Parameters.

Choose the Patch(14) feature and choose OK. You can add and remove Targets and Tools used for Patch Body features, and can change the Tool Face and the Removal Direction. This function is useful if the patch sheet has changed dramatically, or if the part fails during update. To change the Target Body, you would choose the Target Body icon, and shift-select the current target. Then you would select the desired Target Body. To change the Tool Sheet, you need to choose the Tool Sheet icon. When the Remove Tool becomes active, you need to choose it, and then select the desired sheet body. Choose the Tool Sheet selection step icon. The Remove Tool option becomes available. Choose the Remove Tool option, because you need to remove the current tool. Select the new sheet body, and make sure the removal direction is pointing upward. Choose OK until the part updates. Blank the old tool sheet body. The shaded model looks like this.

1156

Close all part files.

Simplify Body This lesson covers using the Simplify Body option. The Simplify option lets you create a parametric simplified solid body, and remove connected sets of faces from it.

Simplify Body is useful when you want to alter a complex model to emphasize key features, but retain the ability to recover the details. Also, simplifying components reduces the amount of data that is loaded when those components are loaded into an assembly.

Creating a Simplified Body

1157 In this activity, you will simplify a model, and close some small holes as you do it.

Creating a Simplified Body Opening the Part Open part file fmf2_simplify.prt from the fmf2 subdirectory, and start the Modeling application.

Creating a Simplified Body Starting the Feature Choose the Simplify Body icon display the Simplify Body dialog.

or Insert

Rotate the model and update the display.

Feature Operation

Simplify to

1158

Creating a Simplified Body Selecting Retained Faces

First, you need to select the Retained Faces. Retained Faces are those that remain on the model after simplification. You must define at least one retained face to let the system know which side of the boundary edges has the faces you wish to keep. The system determines the set of retained faces by identifying all the faces that can be reached from the one(s) you defined without crossing any boundary edges. Select this face as the retained face, and OK the dialog.

Creating a Simplified Body

1159

Specifying Boundary Faces

You need to rotate the view before you select boundary faces. Position the view like this.

The Boundary Faces selection step

is highlighted on the dialog.

You can select boundary faces to help define the boundary edges, because the system defines all of the edges of a boundary face as boundary edges, except for those edges that you deselect. As you specify boundary faces, they are automatically added to the set of retained faces. If you wish, you can return to the Retained Faces selection step and deselect them. When the Simplify Body feature is regenerated during update, the system uses the boundary faces to determine the edges of the faces as they exist at the time of regeneration rather than at creation time. Use Zoom and Fit as needed. Select these three faces as Boundary Faces.

1160

OK the dialog. The Boundary Edges selection step this activity.

is highlighted, but you do not need to use it for

About Boundary Edges

The set of boundary edges divides the faces to be removed from those to be retained. The set of boundary edges that the system selects includes all the edges of faces you selected as boundary faces, plus edges identified by the Automatic Hole Removal option. You could add or remove boundary edges from this set. (Normally you will not need to specify boundary edges.)

Creating a Simplified Body Automatic Hole Removal, and Verify Removed Faces

The Automatic Hole Removal option lets you remove small holes in the part. You need to use a diameter value slightly larger than the size of the hole you want to remove. Toggle on the Automatic Hole Removal. Change the Hole Dia Less Than to 6.5 (millimeters). The smallest holes are now highlighted along with the boundary and retained faces. The system determines the faces to be removed from the defined boundary edges, boundary faces, and retained faces. Sometimes you may want to choose face(s) for the system to verify as removed.

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About Verify Removed Faces

You do not instruct the system explicitly which faces to remove. Instead, the system determines the faces to be removed from the defined boundary edges, boundary faces, and retained faces. You may wish, however, to choose one or more faces for the system to verify as removed. The Verify Removed Faces option is useful when you are concerned that the boundary specification may not be sufficient to partition the body (that is, that there may be a leak through to faces that should be removed). If a leak occurs, then you will have the option of creating a sheet which shows a route from the retained face to the verify remove face. (Studying the sheets can help you determine a better boundary definition.) If you want to use the option, select the face(s) that you expect to be removed in the simplification. It is not necessary to designate every face as being either removed or retained.

You do not need to use Verify Removed Faces in this activity, so it should be toggled off.

Creating a Simplified Body Using Imprint Faces Imprint Faces lets you select a datum plane to create new edges, allowing caps to be defined for wounds that cannot be healed. Below, a datum plane is used to imprint new edges.

Choose Imprint Faces so that you can see the dialog for selecting imprint faces. The Imprint on Faces dialog displays.

Imprint Faces Options

1162

Select Faces

lets you select the faces needed for the imprint edges operation.

The Imprint on options control whether new edges are imprinted only on the selected faces (Selected Faces), or are a loop of edges that pass through the selected face (Connected Faces). If Selected Faces is toggled on, the datum plane will be imprinted only on the faces you select. If Connected Faces is toggled on, the datum plane is used to create a loop of edges that pass through the selected face. This can, for example, be used to create a loop of edges around the interior of a pocket through which a planar cap can be constructed. The edges will update if changes are made to their associative geometry. Select Datum Plane imprinted.

lets you select the datum plane from which the new edges will be

Simplifications must be solids. Removing faces leaves open wounds that must be healed for the simplified body to remain a valid solid. Simplify Body attempts to grow surrounding faces to heal the wounds (adjacent faces may shrink). The system also attempts to create caps through the edges of a wound if the geometry is appropriate.

You will not need to use the Imprint Faces options. Choose Back to return to the earlier dialog.

Creating a Simplified Body Creation Confirmation Options

The creation confirmation options let you review the model before you accept it.

Creation Confirmation Options

If you use No creation confirmation, you will not be asked to confirm before the body is simplified. Confirm before creation prevents you from inadvertently creating the Simplify Body feature before you have defined all the values that you wanted to. Once you have defined enough parameters to create a Simplify feature, whenever you select OK you will be asked to confirm whether the body should be created now (useful if you choose OK to advance selection steps). Review after creation lets you accept or reject the results after the Simplify Body feature is created. If you reject the results, the creation will be undone, and the

1163 Simplify Body dialog will stay open with your previous selections intact. (This minimizes the information to be entered if you only want to change a few variables.)

Choose Review after creation.

Creating a Simplified Body Previewing Faces

The Preview option lets you preview the effect of applying Simplify Body before the original body is modified. Choose the Preview option. Two of the options are active on the dialog that displays: Preview Retained, and Preview Removed.

Preview Options

Preview Retained temporarily highlights the faces that are retained if Simplify Body is applied as currently specified. This option is more likely to be useful when Simplify Body removes interior detail, rather than exterior. Preview Removed temporarily highlights the faces that are removed if Simplify Body is applied as currently specified. It is generally more useful when exterior detail is removed. Create Sheets is active only when the parameter definitions allow faces that you selected for Verify Removed Face to be reached from faces that are retained. This option creates a sheet body between each reachable face and the retained face from which it is reachable (as long as the reachable face was one on which you request verification of removal). The sheet body will be shaded in partially shaded views if your graphics device supports shading.

The Preview Retained option temporarily highlights the faces that will be retained if Simplify is applied as currently specified. This option is more likely to be useful when the simplification will remove interior detail, rather than exterior. Choose Preview Retained to view all faces that will be retained.

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The Preview Removed option temporarily highlights the faces that will be removed if Simplify Body is applied. It is generally more useful when exterior detail is to be removed. Choose Preview Removed to view all faces that will be removed.

Creating a Simplified Body Result of Simplification You will not have to make any other selections on the dialog or in the view. Choose Apply. The Result of Simplification message tells you how many faces were removed and how many faces remain. Choose OK on the Result of Simplification dialog.

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Choose OK on the dialog to continue to simplify the model.

Creating a Simplified Body Result of Simplification You will not have to make any other selections on the dialog or in the view. Choose Apply. The Result of Simplification message tells you how many faces were removed and how many faces remain. Choose OK on the Result of Simplification dialog.

Creating a Simplified Body Accepting the Result Because you specified Review after creation, an accept/reject dialog displays. Even though the simplification is correct, and you could accept the result, choose the Reject Result to see what happens. You are returned to where you left off before you started the simplification. The system remembers all your inputs, and you could change them now, if you wanted to. Instead, you can Apply the simplification and finish this part. Change your confirmation to Confirm before creation, and choose Apply. To complete the simplification, choose OK in the Result of Simplification dialog.

1166 The body is simplified.

Rotate the model and examine the simplified body. The two small holes have been filled, because you specified that Automatic Hole Removal be performed for holes smaller than 6.5 millimeters in diameter. Cancel all dialogs. Close all part files.

Wrap Geometry This lesson covers creating Wrap Geometry features, which are simplified models. The Wrap Geometry option computes a solid envelope that surrounds the model. If the model is edited, the wrap geometry feature updates.

1167 Wrap geometry features are useful for conveying the shape while withholding proprietary information, or for allocating approximate model space, or for initial development of a solid body from wireframe geometry. The Wrap Geometry feature can be Suppressed, Deleted, and Reordered. You can also find Information on the feature.

Creating a Wrap Geometry Feature In this activity, you will create a wrap geometry feature that looks like this.

After creating and editing the wrap geometry feature, you will edit the block feature and all other features will update, including the wrap geometry feature.

Creating a Wrap Geometry Feature Opening the Part Open part file fmf2_wrap.prt from the fmf2 subdirectory, and start the Modeling application.

Creating a Wrap Geometry Feature Starting the Wrap Feature

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Choose the Wrap Geometry icon Geometry.

or Insert

Feature Operation

Wrap

The Wrap Geometry dialog displays.

Distance and Offset Options on the Wrap Geometry Dialog

The Confirm Upon Apply option, near the bottom of the dialog, lets you view the new feature before accepting it. The Filter options include Any, Body, Curve, and Point. You can select any number of objects to wrap. Distance Tolerance lets you control how closely to the original geometry will be to the wrap geometry. This will default to one hundred times the part's distance tolerance. A small distance tolerance applied to a very complex solid can be time consuming. It is used to generate points that are used to calculate the envelope. For curves this value equates to the maximum chordal deviation. For bodies this equates to the maximum facet to surface deviation. Additional Offset lets you make the wrap solid a given value bigger than the minimum size.

Toggle on the Confirm Upon Apply option. The Geometry to Wrap wrapped.

selection step is active, so you can select the geometry to be

You need to select the objects (solids, sheets, curves or points) in the current work part to be wrapped. The selected objects (like points or sheets) should not be coplanar since you will be creating a solid body. Optionally, you can set the Filter to Body. You need to wrap the solid body in this part file. Select the solid body. The system converts your selections to points which are wrapped in a set of planar faces. The faces are then offset to enclose the original geometry. Use the default Distance Tolerance value.

1169 The faces of the solid can be offset slightly outward to ensure that the solid encompasses all the original data. Use the 0 as the Additional Offset value.

Creating a Wrap Geometry Feature Closing Gaps using the Beveled Option You can specify how to close the gaps between faces.

Close Gaps Options on the Wrap Geometry Dialog

If you use Sharp, each planar face is extended until it meets adjacent faces. Gaps smaller than tolerance are closed using sharp edges. If you use Beveled, planar faces are added in gaps to create a beveled effect. To avoid creating tiny faces, bevels will not be narrower than Distance Tolerance. If you use No Offset, faces are not offset. This is faster but the result usually does not enclose original data.

Use the Beveled option for Close Gaps. Use of splitting planes is optional, so you will create this wrap feature without using them. Choose Apply to create the feature. The wrap feature is temporarily created. Notice the bevels at the lower edge of the feature.

Creating a Wrap Geometry Feature

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Checking the Feature The dialog of confirmation options displays. At this point, you could perform a variety of checks before you accept the feature. Choose OK to complete the feature. The new feature (in green) simplifies a detailed model. The solid envelope which surrounds the model is composed of a convex polyhedron of planar faces. Shade the model. Notice the planar faces have been created.

Return to a Wireframe mode. Orient the view to the Right view. Notice the distances between the walls of the model and the wrapped geometry. This distance is controlled by the Distance Tolerance that you used. Return to a Trimetric view. Cancel all dialogs.

Creating a Wrap Geometry Feature Closing Gaps using the Sharp Option As you edit the parameters of a Wrap Geometry feature, you can change any of the parameters. You will change the method to close gaps and see how the wrap feature is modified.

1171 Double-click on the wrap geometry feature to edit its parameters. The Wrap Geometry dialog displays. Notice that all fields for creation are available for editing. You do not need to reselect the object(s) to be wrapped, since no change is being made to them. Change Close Gaps to Sharp and choose OK on the dialog. You will not be using a splitting plane yet. Choose OK when the dialog changes to permit you to select splitting planes. Notice that fewer planar faces are present, and that the beveled areas are no longer present.

Shade the view. Return to a Wireframe display mode.

Creating a Wrap Geometry Feature Displaying the Datum Plane Next, you will use a datum plane (splitting plane) to make the wrap feature match the model like this.

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First, you need to make the datum plane selectable. The datum plane is located on layer 62. Make layer 62 Selectable. The datum plane displays. It is located on the top face of the block feature.

Creating a Wrap Geometry Feature Adding a Splitting Plane to the Wrap Geometry Feature Double-click on the wrap geometry feature to display the Wrap Geometry dialog again. The Wrap Geometry dialog displays. To make the wrap feature more closely match the shape of the model, you can reduce the distance tolerance. Change the Distance Tolerance to 0.25 and use Sharp as the Close Gaps option. You will not need to use an additional offset. Use 0 as the Additional Offset value.

1173 You will add a splitting plane, so you need to choose the Splitting Planes selection step. Choose the Splitting Planes icon. The dialog now displays options for specifying splitting planes. Select the datum plane in the view.

As each plane is specified, it is listed in the Defined Planes field. "Plane 1" is now listed in the dialog.

Using Planes to Split a Wrap Geometry Feature You can use 0 (zero) for the Split Offset since you only have one splitting plane. Choose OK on the Wrap Geometry dialog. The wrap feature now more closely follows the shape of the model.

A very small distance tolerance value results in a wrap feature that closely matches the shape of the model, but may also take longer to create. The model is now more closely wrapped. Shade the model.

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Rotate the model to see the many facets. Return to Wireframe mode.

Creating a Wrap Geometry Feature Editing the Block and Updating the Wrap Feature The wrap solid is associative with the selected geometry. If the geometry changes, the wrap solid updates. You will change the size of the block and update the model.

Choose the Edit Feature Parameters icon

or Edit

Feature

Parameters.

The Edit Parameters dialog displays. Choose the Block feature on the dialog and choose OK. Choose Feature Dialog on the Edit Parameters dialog. Change the X Length to 65, the Y Length to 20, the Z Length to 15, and OK three times. Fit the view. The shaded view of the wrap geometry and the model update, and looks like this.

Close all part files.

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Copy and Paste Features This lesson covers the Copy Feature and Paste Feature options. These options let you copy features from one part file or model and paste them into another part file or model, and also lets you specify that the associativity remains in tact.

To copy and paste features, the setting for "Assemblies_AllowInterPart" in your Customer Defaults file (ug_english.def or ug_metric.def) must be set to "yes", otherwise, the system will not paste the feature. Check with your system manager to change the customer defaults file, if you cannot complete this activity.

Using Copy Feature / Paste Feature In this activity, you will copy a feature from this model:

and add it to this model. Then, you will edit the original model and update the model that contains the pasted feature.

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Using Copy Feature / Paste Feature Opening the Part Open the part file fmf2_copy.prt from the fmf2 subdirectory, and start the Modeling application.

This part has a general pocket that was created using the curves you see as the Placement Outline. The curve projection method was Normal to Plane of Curves, and the Taper Angle was from Plane Normals. Set the view to a Wireframe display.

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Using Copy Feature / Paste Feature Copying a Feature When you copy features, the system places them onto a clipboard, and then you can paste them onto a different face and/or location. You can paste them onto a different solid in the current part file, or into a different part file. You will copy the pocket in this model onto another model. Choose Edit

Copy Feature.

The Copy Feature dialog displays. Near the middle of the dialog, the Add Dependent Features option is toggled on, so features that are dependent on the pocket will also be selected. The features you wish to copy can be selected either on the graphics screen or from the top portion of the dialog. Scroll to the bottom of the list and choose the GENERAL_POCKET(12) feature. The general pocket feature and any children of the pocket appear in the Selected Features list box in the lower part of the dialog. You can deselect features by shift-selecting on the graphics screen, or by selecting them from the lower part of the dialog. Choose OK. The feature has been copied onto the clipboard.

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Using Copy Feature / Paste Feature Pasting a Feature You can paste the feature onto another face, another model, or onto a model in another part file. Open the part file fmf2_paste.prt from the fmf2 subdirectory. As before, change to a wireframe display. You will paste the feature onto the model in that part file.

Choose Edit

Paste.

The Paste Feature dialog displays.

It will list all the required constraints for pasting this feature.

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Using Copy Feature / Paste Feature Controlling Transfer Modes The Expression Transfer Mode controls how the system will create expressions for the new feature, or whether or not it will create them at all.

Expression Transfer Modes

New - The system will create completely new expressions. Link to Original - The system will create new expressions and set their value equal to the old expression (for example p284=p36). (If the destination is in a part file other than that of the original, the system will create Interpart Expressions to handle this.) Instance of Original - No expressions will be created. The pasted feature will be linked to the original - if it changes, so does the pasted feature. (If the destination is a file different that the original file, the system will create Interpart Expressions. This will operate the same as the Link to Original option.)

Choose Link to Original as the Expression Transfer Mode. The Parent Transfer Mode controls what the new feature will see as its parents (curves and sketches that have been extruded into the feature being pasted).

Parent Transfer Modes

Parent Transfer Modes work in conjunction with the constraint list in the lower part of the dialog. This list contains all the parents needed for the new feature. The symbol (-) in front of an item indicates it is yet required. Once a parent has been selected, the symbol will change to (+). Copy Original Curves This will create a copy of the original curves (the curves that the original "copied" feature was generated from). When this is chosen, all the constraints in the list which are for curves, will show a (+) immediately. Prompt for New You must select new curves for the feature to be generated from. You can use the same number of curves or fewer, but you cannot select more.

1180 Instance of Original This will use the same curves, and will create a duplicate feature in the same location. .

You will be creating an instance of the pocket you copied onto the clipboard from the previous part. You will be using the curves you see for the Placement Outline. As the Parent Transfer Mode, use Prompt for New.

Using Copy Feature / Paste Feature Specifying Constraints for the Pasted Feature The first line in the list box displays: (-) Top surfaces from GENERAL_POCKET(12). Whenever this symbol (-) displays in front of a reference, then the selection must be made. The system is asking that you specify the top surface for the pocket location. With the first constraint highlighted, select the top face of the part as the placement face for the pocket.

The first constraint now has a (+) in front of the statement, because it has been satisfied. The remaining lines that start with "(-) Top outline" indicates that you need to select the select the placement outline curves. You need to select the outline strings for the pocket. A separate object exists for each curve. Select all the orange curves in order. As you select each curve, you will notice that the minus sign is converted to a plus sign in the dialog.

1181 Choose OK because all of the reference prompts have been satisfied. Remember, if you get a message box that displays "Interpart expressions disabled in Customer Defaults file", then the system will not paste the feature. The pocket is pasted onto the model.

Using Copy Feature / Paste Feature Editing the Copied Feature If you change the original feature, the pasted feature will update. Choose File Recently Opened Parts contained the pocket that you copied.

/../../fmf2_copy.prt to display the first part that

You need to change the parameters of the placement and floor radii of the general pocket feature.

Choose the Edit Feature Parameters icon

or Edit

Feature

Parameters.

You need to select the general pocket feature. Choose GENERAL_POCKET(12), and OK. The general pocket dialog displays parameters. On the General Pocket dialog, change the value of the Placement Radius to 0.625, and the value of the Floor Radius to 0.125.

1182 Choose OK until the part updates.

Using Copy Feature / Paste Feature Checking the Pasted Feature If you look at the part that received the pasted feature, you will find that it, too, has been updated. Choose File

Recently Opened Parts

/../../fmf2_paste.prt.

Notice that the Placement Radius and the Floor Radius values have changed here too. Close all part files.

1183

Feature Sets This lesson covers creating Feature Sets. The Feature Set option lets you group features together as one feature. These sets can be named uniquely, edited, and manipulated as one feature.

Some examples of editing functions that can be performed on feature sets include suppress, move, and delete.

Using Feature Sets In this activity, you will create a feature set of the boss, simple hole, and symbolic thread. The chamfer and blend will not be included.

Using Feature Sets Opening the Part Open part file fmf2_feature_set.prt from the fmf2 subdirectory, and start the Modeling application.

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Change to a wireframe display.

Using Feature Sets Starting the Feature Set

You will group the boss, simple hole, and symbolic thread. Choose Format

Group Features.

The Sets of Features dialog displays. The Feature Set Name field is where you key in a unique name for the feature set. You cannot use spaces in the name, but you can use underscores. Key in hole_set as the Feature Set Name. Sets of Features Dialog Options

The Filter field lets you limit the list of features to the string you key into the field. In very large parts, this can make feature selection much easier. The Add Dependencies option, when on, lets you quickly add all dependent features. This option needs to be set before you choose the feature(s) to add to a set. The All in Body option, when on, lets you quickly add all features in the body. This option needs to be set before you choose the feature(s) to add to a set.

Toggle on the Add Dependencies option. If needed, toggle off the All in Body option. Recall that the chamfer, hole, thread and blend are all features that are dependent on the boss feature.

1185 You can create an empty feature set by providing a name, but not adding any features. You need to select the boss and threaded hole for the set, and press the right arrow symbol to add them to the Features in Set list box. Choose the Boss(9) feature from the Features in Part list in the dialog. Choose the Add symbol

to add the boss to the Features in Set list.

Notice that all dependent features have been added to the Features in Set list box. Notice that the entire set of features is highlighted in the view.

Using Feature Sets Removing Features from the Set You will remove the blend and chamfer from the feature set. From the Features in Set column, choose (or select in the view) the Chamfer(11) feature. Choose the Remove arrow

to remove the chamfer from the list.

You also need to remove the Blend feature. From the Features in Set column, choose (or select in the view) the Blend(10) feature. Choose the Remove arrow

to remove the chamfer from the list.

Hide Feature Set Members controls whether or not the features in the set will be listed independently in lists of features, such as for Edit Parameters. Leave this option toggled off, so that you can see the members of the feature set.

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Choose OK to create the feature set. The feature set is created. If you were to open the Model Navigator, you would notice that the hole_set feature is listed. Once a feature set is created, you can use it as you would use other features in a model. Although you created a feature set of existing features, you can also create Feature Sets of several Feature Sets. The parameters of feature sets can be edited. If you want to add features during edit, you can add only features which were created before Timestamp of the Set feature. You can delete all the Set members by using the Edit and select the features to delete.

Delete option, choose Features,

Other editing options for feature sets include: suppressing/unsuppressing the feature set, reordering the feature set, and hiding/displaying members from all feature menus. Close all part files.

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Editing Features This lesson covers many types of editing options in the Modeling application. These are listed below.

Edit Solid Density Suppress Feature Unsuppress Feature Reordering Features Removing Parameters Playback Deleting Features Edit During Update Resize Fixed Datums

Editing Solid Density of Features In this activity, you will edit the solid density of the model. The default solid density can be set on the Modeling Preferences dialog.

Editing Solid Density of Features Opening the Part Open part file fmf2_edtposdim.prt from the fmf2 subdirectory, and start the Modeling

1188 application.

Change to a Gray Thin Hidden Edges view.

Editing Solid Density of Features Editing the Solid Density The Edit Solid Density option lets you change the density and/or the density units for one or more existing solid bodies. Every solid body is given a density value, which defaults to the value in the settings on the Modeling Preferences dialog. The density value represents the material from which the part is to be made. The density is used in analysis functions to find the mass properties of the part. You will edit the solid density now.

Choose the Edit Solid Density icon

or Edit

Feature

Solid Density.

The dialog displays the current density.

Check the current units of measure by looking at the cue line and read the value in the solid density field of the dialog. Choose Change Units and notice that you could change the units to Lbs-Inches, Lbs-Feet, Grams-Cm, or Kg-Meters.

1189 Choose Back. You will continue to use pounds per cubic inch. The solid density that currently exists is 0.2829 lbs/cubic inch. This is close to the density of carbon steel. You will now change the value to one closer to that of an aluminum alloy. Key in .098. Choose OK. Select the body in the view. Choose OK. Cancel the Edit Solid Density dialog.

Editing Solid Density of Features Checking the Model Density If you were to use Information, Object, type, Solid Body, and select the body, you would find that the density is now 0.098. You can do this now. Choose Information

Object.

On the Class Selection dialog, choose Type. Choose Solid Body and OK the dialog. Select the solid body in the view, and OK the dialog. The information window displays the new density value of .098 along with other information about the solid body. Close the information window. Cancel the dialog. Close all part files.

Suppressing and Unsuppressing Features In this activity, you will suppress and unsuppress a datum plane. The features that are dependent on suppressed features will be suppressed automatically.

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About Suppressing and Unsuppressing Features

The Suppress Feature option lets you temporarily remove one or more features from the target body and the display. Suppress Feature is not available if Delayed Update on Edit is active. A suppressed feature still exists within the file but it is removed from the model. Since the features still exist, they can be retrieved using Unsuppress Feature. It is recommended that you do not create new features where a suppressed feature exists. Reasons for using Suppress Feature include the following. Suppressing features will reduce the size of a large model. This speeds up creation, object selection, edit, and display time. Suppressing noncritical features, such as small holes and blends, speeds up analysis work. Suppressed features are not meshed in GFEM Plus. Suppressing features can be used when you create features in locations where there is conflicting geometry. For example: If you need to position a feature using an edge that has already been blended, you do not need to delete the blend. You can suppress the blend, create and position the new feature, and then unsuppress the blend.

Suppressing and Unsuppressing Features Opening the Part Open the part file fmf2_edtposdim.prt from the fmf2 subdirectory, and start the Modeling application. You will suppress a feature now.

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Change to a Gray Thin Hidden Edges view.

Suppressing and Unsuppressing Features Suppressing a Datum Plane

The Suppress Feature option datum plane.

lets you cause features to not display. You will suppress a

Suppressed features are not deleted. They exist within the part file but are not displayed. Also, in the Model Navigator, the boxes to the left of the feature nodes indicate whether features are suppressed or unsuppressed. Checked features are unsuppressed, unchecked features are suppressed. To change the status, just click on the small box next to the desired feature.

Choose the Suppress Feature icon

or Edit

Feature

Suppress.

Choose DATUM_PLANE(3) on the dialog. In the Suppress Feature dialog, if List Dependents is turned on, then all features that are dependent on the selected datum plane are now listed in the lower list box. When you suppress a feature that has additional features associated with it, all of the associated features will also be suppressed. OK the Suppress Feature dialog. The datum plane and the associated hole feature are both suppressed. This is because the hole was associated to the datum plane.

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Suppressing a datum plane is not the same as Blanking it. You can blank a datum plane and dependent features would not be blanked.

Suppressing and Unsuppressing Features Suppressing an Instance Array You will suppress an instance array next.

Choose the Suppress Feature icon

or Edit

Feature

Suppress.

Choose RECTANGULAR_ARRAY(7) on the dialog. All instances of the hole are listed under Selected Features. Selecting an instance from an instance array will only suppress the instance and not the entire set.

If you do not also select the counterbored hole used for the array, only the three instances will be suppressed, and the original hole will not be suppressed. In the dialog, choose the INSTANCE[0](2)/COUNTER_BORE_HOLE(2) feature (press MB1 to select it). All 4 instances are highlighted.

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OK the Suppress Feature dialog.

Do not close the part yet, because you will now learn how to unsuppress features.

Suppressing and Unsuppressing Features Unsuppressing Features

The Unsuppress Feature option features.

lets you display any or all previously suppressed

Any feature that is associated to a selected feature will also be selected. You cannot use Delayed Update when you want to unsuppress features. You will unsuppress the hole, datum plane, and all four counterbored holes.

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Choose the Unsuppress Feature icon

or Edit

Feature

Unsuppress.

You cannot select features in the view. You must select suppressed features to be unsuppressed from the dialog. The dialog displays all objects that have been suppressed. You could selectively unsuppress features, but you will unsuppress all of them.

Select all the features listed in the Unsuppress Feature dialog. OK the Unsuppress Feature dialog. The system regenerates the model and displays all previously suppressed features.

Close all part files.

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Reordering Features In this activity, you will reorder the hollow feature before the pad feature.

Reordering Features Opening the Part

Open part file fmf2_reorder.prt from the fmf2 subdirectory, and start the Modeling application.

Make the hidden edges visible. You can see that the pad and slot are hollowed.

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Reordering Features Starting the Reorder Feature Function

The design change requires that the pad and slot not be hollowed. The Reorder Feature option body.

lets you change the order in which features are applied to a

Using this option you can simplify your work, and reduce the effort needed to make certain design changes.

Choose the Reorder Feature icon

or Edit

Feature

Reorder.

The Reorder dialog displays. All features appear in the list box with their Timestamp (order of creation) in parentheses. The filter option lets you control the types of features displayed in the Reference Feature list box. The Filter can substitute any of the following wild cards for literals to select a range of features: a ? (question mark) substitutes for any single character except a period; an * (asterisk) substitutes for any character string, including strings with a period and null strings.

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To use the dialog, you need to select a feature that you want to use as Reference Feature in the top list on the dialog. This will be the feature that you want something else to be before or after. You can also select a Reference feature directly from the graphics window.

Reordering Features Reordering a Pad, Slot, and Hollow Feature The desired feature(s) can be reordered before or after a selected reference feature. You need to choose the method: Before or After. Before places the next selected feature before the Reference Feature. After places the next selected feature after the Reference Feature. Scroll to the bottom of the list in the dialog. The rectangular pad and slot are 7 and 8. The hollow is 9. You can now select a reference feature. The reference feature is the feature about which the repositioned feature will be placed. You can select the feature with the cursor in the view or by choosing from the list of features in the Reorder Feature dialog. You can deselect a feature by clicking on it in the graphics window with . From the Reference Feature list, choose RECTANGULAR_PAD(7). Because you want to move the hollow, before the rectangular pad, you need to specify that the Choose Method be Before. Choose Before.

1198 Now the lower part of the dialog lists features after which the pad can be positioned.

The bottom list lists all the features that can be reordered based on your choices (Before and rectangular pad). From the Reposition Features list box, choose HOLLOW(9).

Reordering Features Completing the Reorder Choosing Apply performs the reorder on the selected feature only within the list box. You can perform multiple reorders. Choosing OK completes the reorder. You must Apply and OK the reorder. Choose Apply to complete the reorder. The hollow is now numbered 7, and the rectangular pad and associated slot are now numbered 8 and 9.

You must OK the dialog for the feature(s) to be reordered.

1199 OK the dialog. The pad and slot are no longer hollowed.

If you had chosen Cancel and the system would abort the changes, no reorder would have been performed. Features are reassigned Timestamp numbers.

Reordering Features Suppressing a Feature by Using an Expression

The Suppress by Expression icon lets you assign an expression to a feature. This expression will control the feature's suppression status and will act like a switch. If the expression is set to one (1), the feature is unsuppressed; if it is set to zero (0), it is suppressed. This option is useful if you were to create a "maximum" part in which many types of features existed but not all at the same time. For example, a part could have blends or chamfers, depending on the suppression status.

Choose the Suppress by Expression icon Expression.

or Edit

Feature

Suppress by

A Suppress by Expression dialog displays. The Create for each option is toggled on.

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You can use the first two options on the Suppress by Expression dialog to create the suppression expression for a single or a group of features. You can also Delete the suppression expression for a single feature or a group of features.

Reordering Features Creating the Suppression Expression You will create a suppression expression for the hollow feature. Choose HOLLOW(7) on the dialog. Choose the Apply option to create the suppression expression. Choose the List option to see the expression that has been created for the hollow feature. The feature name, HOLLOW(7), is listed at the left side in the information window. The expression that controls the suppression/unsuppression for the hollow(7) feature is p58=1. The value is equal to one because the hollow is currently unsuppressed (feature is displayed). When the value is changed to zero, the feature will be suppressed. Close the information window. Cancel the Suppress by Expression dialog.

1201 Using suppression status, you can control feature suppression status and incorporate it into the design intent of your model. A feature, whose suppression status is controlled by an expression, may be in conflict with the manual suppression (Suppress Feature) or unsuppression (Unsuppress Feature) of features. A couple of rules should prevent such conflict. Parent Child feature relationships will always be preserved. The design intent is always preserved.

Reordering Features Using the Suppression Expression

Now that you have created a suppression expression, you can use it to suppress the feature. Choose Tools suppression.

Expression to access and change the expression that controlls

The dialog displays the expressions in this part file.

Scroll down the list in the dialog. Notice that p58 is listed. This expression, p58=1, controlls the suppression status. Choose the expression p58=1 in the list of expressions. The expression displays in the editor field.

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In the editor field, change the value from 1 to zero (0).

Press Enter on your keyboard to change the equation in the list box to p58=0. Then choose Apply on the Expressions dialog. The hollow is suppressed.

Cancel the dialog and close all part files.

Removing Parameters

In this activity, you will remove parameters from this parameterized model.

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Removing Parameters Opening the Part Open part file fmf2_hub.prt from the fmf2 subdirectory, and start the Modeling application.

Removing Parameters Starting the Removing Parameters Function Remember, you can use the Model Navigator to check the feature before and after removing parameters. When parameters are removed from the model, the model will display the same as before, but because the parameters are removed, editing the model becomes more difficult. In this model, the datum planes are associated with many features, and all features are parametric.

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The Remove Parameters icon lets you remove all parameters from selected models (solids or sheets). You can also remove parameters from curves and points that are associated with features, making them non-associative. Although you can remove parameters for curves and points, you cannot remove parameters from sketch curves. If Delayed Update on Edit is active the Remove Parameters option.

Choose the Remove Parameters icon

, many edit options are not available, including

or Edit

Feature

Remove Parameters.

The Remove Parameters dialog displays. You can select existing named objects by entering their names, or use the filter mask to filter for your selection. The filter options include: Any, Body, Curve, and Point.

Removing Parameters Removing Parameters from the Solid Body For this activity, you will remove parameters of the solid body. You need to select the objects for which parameters should be removed. You can use the filter mask, if necessary, to restrict your selection. If you know the name of an object whose parameters you wish to remove, you can select it by entering its name in the Name field and pressing the return key on the keyboard. Otherwise, you can select the object using the mouse and cursor. Select the yellow solid body and choose OK. A warning message appears that lets you know that parameters of selected objects will be removed. You must ok this message to continue to remove parameters.

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If you cancel the warning message, the parameters will not be removed. Choose OK on the warning message to remove parameters. If you were to save the part file (using File Save, File Save As, or File at this point, you would not be able to Undo the removal of parameters.

Save All)

Cancel the Remove Parameters dialog. The parameters have been removed from the model, but the display is the same as before.

The model now contains an unparameterized feature and three datum planes.

Close all part files.

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Using the Playback Option In this activity, you will use the Playback option to see how this model was constructed.

Using the Playback Option Opening the Part Open the part fmf2_playback.prt from the fmf2 subdirectory.

Start the Modeling application. The Edit feature.

Feature

Playback option lets you review how the model is created, feature by

You can also edit the model as it updates. You can move forward or backward to any feature, then edit it. Then you can move to a different feature. Or, at any time, you can trigger an updating of the model that starts at the current feature and continues until the model is complete, or until a feature fails to update. Playback gives you more control over the update process than the other update methods.

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Using the Playback Option Starting the Playback Choose the Feature Playback icon

or Edit

Feature

Playback.

The Edit during Update dialog displays various options. This dialog may also appear if a failure or a warning occurs while you are updating your model.

The message window of the Edit during Update dialog shows any applicable error or warning messages, as well as whether the current feature updated successfully or failed. When a feature fails to update, the Accept option will automatically suppress the feature, and mark it Out of Date on the Model Navigator. The Show Failure Area option temporarily displays failed geometry, if any exists. The Post Recovery Update Status option lets you specify what should happen when the icon option you choose is completed. Continue restarts the automatic update process from where it left off. Pause lets you choose other Edit during Update options, rather than automatically resuming update. Using the icon options at the bottom of the dialog, you can step through the feature build, or edit features as you go.

Using the Playback Option Playing Each Step of Model Creation A sketch and datum planes display.

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As you play back the part, the system will not suppress the display of Datum Planes, Axes, or Curves/Sketches, so, you will need to watch the screen carefully for a flicker to see which feature was just updated. The Step icon

lets you advance one feature at a time through the model.

Choose the Step option formed.

a number of times, until the basic shape of the wheel has been

Notice that once you have started to step through the model, the other icons are active.

The Step To icon

lets you move forward through the model to a selected feature.

Choose the Step To icon.

1209 The Update Selection dialog displays. The dialog lists features created before the current one, in the order of creation. Choose the SIMPLE_HOLE(9) item. The selected item displays in the Object Selection field.

Choose OK on the Update Selection dialog. The Edit during Update dialog redisplays, and you can now choose to display the current model. The Show Current Model option displays the part of the model that has been successfully rebuilt. Choose Show Current Model to display the model at this point. Notice that the simple hole is located on the top outer area of the model.

You can use the other icons as follows: The Go Back To

icon lets you move backward through the model to a selected feature.

1210 From the Update Selection dialog, you choose a feature from the list of the features created before the current one. The Step Back

icon lets you move backward through the model one feature at a time.

The Continue icon triggers the update process, which continues until the model is completely rebuilt or until a feature fails. If you choose Continue when a failure occurs, that feature is skipped. Choose Continue icon The Edit The Undo began.

to complete the playback.

icon lets you change the parameters of the feature currently being updated. icon undoes the last modification you made to the model before updating

Refer to the Unigraphics NX online help for more details about the options on the Edit during Update dialog. As you rebuild the part, the system will not suppress the display of Datum Planes, Axes, or Curves/Sketches. So you will need to watch the screen carefully for a flicker to see which feature was just updated. Close all part files.

Editing Features During Update In this activity, you will need to use the Edit During Update function when you remove the slot and blend located in the middle of the plate.

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Editing Features During Update Opening the Part Open the part file fmf2_edit_during_update.prt from the fmf2 subdirectory. Start the Modeling application.

Change to a wireframe view.

Editing Features During Update Selecting Features to Delete Sometimes, when you are editing models, the system will be unable to complete the edits you request. In cases like this, the Edit during Update dialog may display. In this part file, if you delete the center slot, the system will complete the edit without displaying the Edit during Update dialog.

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Choose the Delete icon

,or choose Edit

Delete.

The Class Selection dialog lets you select features to delete. Choose Features on the Class Selection dialog. A Select Features dialog displays. Select the slot and the blend in the view. The Rectangular slot and the blend are listed in the Select Features dialog, and are highlighted in the view. Choose OK on the dialog. A Notification displays that lets you know that deleting these objects will affect other features.

Editing Features During Update Checking the Model Choose Information on the Notification dialog and look at the information in the window. Notice that when you delete the rectangular slot, four positioning dimensions will be deleted also. Close the Information window. Choose OK on the Notification dialog to delete these features. The rectangular slot and blend are deleted from the part. Along with slot, you deleted the four positioning dimensions.

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To continue the activity, where you will suppress the slot, you need to return the model to its prior state.

Undo

the delete to return the model to its prior state.

Editing Features During Update Suppressing the Rectangular Slot and Blend Some edits cause the Edit During Update dialog to display. In this model the four holes are positioned to the center line of the rectangular slot. If you suppress the slot, the positioning dimensions for the counterbored holes will need to be respecified. The Edit during Update dialog will let you relocate positioning dimensions created relative to the suppressed feature(s).

Choose the Suppress Feature icon

or Edit

Feature

Suppress.

1214 The Suppress Feature dialog displays. Choose the RECTANGULAR_SLOT(18), and OK the dialog.

Editing Features During Update Using the Edit During Update Dialog The Edit During Update dialog displays, because of missing positioning reference(s).

At this time, the dialog tells you that you will lose a positioning dimension for counterbored hole(19). You can correct this situation by using the Edit Parameters icon on the dialog to Reattach the required positioning dimension. The Accept All option will suppress the feature that you are being notified of, and all other features that cannot update. It will mark all of these Out of Date.

Choose the Edit icon

on the dialog.

The next dialog displays options that are available for editing the selected feature.

Choose the Edit Parameter icon

on this dialog.

You can use the Feature Dialog to change the parameters of the selected feature, use Reattach to reattach the deleted positioning dimensions, or use Change Type to change the selected feature to another type.

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Editing Features During Update Reattaching Positioning Dimensions for the First Hole You need to reattach a positioning dimension that had previously been attached to the slot. Choose Reattach from the dialog of editing options. The Reattach dialog displays.

The graphics screen updates to display the current model with the hole in question highlighted, and the Reattach dialog displays. You need to redefine the positioning dimension. You can use the Redefine Positioning Dimension icon on the Reattach dialog to do this. Choose Redefine Positioning Dimensions. Zoom in on the area of the hole, if you need a larger image. You need to select the dimension that had been associated with the slot. Select the p38 dimension that has an extension line leading to nothing.

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Now you need to select a new target. For the new target edge, select the top left edge.

Choose OK three times. The Edit During Update dialog redisplays. Choose Show Current Model on the Edit during Update dialog. Now, notice that the dialog shows the COUNTER_BORE_HOLE(20) is missing a positioning reference.

Editing Features During Update Reattaching Positioning Dimensions for the Second Hole You need to reattach a positioning dimension for the COUNTER_BORE_HOLE(2).

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Choose the Edit icon

on the dialog.

Choose the Edit Parameter icon

on the next Edit During Update dialog.

Choose Reattach from the dialog of options. The graphics screen updates to display the current model with the hole in question highlighted. Again, the Reattach dialog displays. Choose Redefine Positioning Dimensions. Remember to use Pan and Zoom as needed. Select the p40 dimension. For the new target edge, select this edge.

Choose OK three times. The large Edit during Update dialog redisplays. Choose Show Current Model on the Edit during Update dialog. Now, you need to provide the positioning for the COUNTER_BORE_HOLE(21).

Editing Features During Update Reattaching Positioning Dimensions for the Third Hole Repeat the procedure for the third hole. Choose the Edit icon

on the large Edit During Update dialog.

Choose the Edit Parameter icon

on the small Edit During Update dialog.

1218 Choose Reattach. The graphics screen updates to display the current model with the hole in question highlighted. Choose Redefine Positioning Dimension. Remember to use Pan and Zoom as needed. Select the p43 dimension. For the new target edge, select this edge.

Choose OK three times. The Edit during Update dialog redisplays. Choose Show Current Model. Now, the COUNTER_BORE_HOLE(22) is missing a positioning reference.

Editing Features During Update Completing the Model Repeat the reattach procedure to complete the last hole. Choose the Edit icon

on the large Edit During Update dialog.

Choose the Edit Parameter icon

on the small Edit During Update dialog.

Choose Reattach. The graphics screen updates to display the current model with the hole in question highlighted.

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Choose Redefine Positioning Dimension. Use Pan and Zoom as needed. Select the p46 dimension that has an extension line leading to nothing. Select this edge.

Choose OK three times to complete all changes. You have completed all the needed changes. Fit or Regenerate the view as needed to see the updates. The model is updated, and the Edit during Update dialog no longer displays. All four holes are fully constrained.

Close all part files.

Resizing Fixed Datums In this activity, you will use the Resize Fixed Datums option.

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When you create a fixed datum plane after a feature has been created, and add more features to the model, the fixed datum plane can be resized to that of the modified model.

Resizing Fixed Datums Opening the Part and Creating a Fixed Datum Plane Open part file fmf2_resize.prt from the fmf2 subdirectory, and start the Modeling application. First, you will create a fixed datum plane on the YC-ZC plane.

Choose the Datum Plane icon

or Insert

Form Feature

Choose the Datum Plane Dialog icon in the view.

Choose the Fixed Datum icon

on the Datum Plane dialog.

Choose YC-ZC. Choose OK to create a fixed datum plane. The first datum plane is created.

Datum Plane.

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Resizing Fixed Datums Creating and Uniting a Cylinder Now, you will create and unite a cylinder and unite it to the existing cylinder.

Choose the Cylinder icon

or Insert

Form Feature

Cylinder.

Choose the Diameter, Height method. Choose the YC Axis icon. Choose OK. Now, you need to specify the parameters of the cylinder. Key in a Diameter of 1, a Height of 6, and OK the dialog. The Point Constructor dialog displays. You need to specify the base point for the cylinder. Key in the Base Point values for XC as 5 , YC as -3 , and ZC as 0, and OK the dialog. Choose Unite as the Boolean operation. Cancel the dialog. You modified the model, but the fixed datum plane remains at its original size.

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Resizing Fixed Datums Resizing the Fixed Datum Plane You will resize the datum now. Choose Edit

Feature

Resize Fixed Datums.

Fit the view.

Resizing fixed datum is useful, particularly as your model becomes larger and you need to have the datum plane edges easily selectable. Close all part files.

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Replacing Features This lesson covers using the Replace Feature option. The Replace Feature option lets you make changes to the basic geometry of a design without having to remodel all of the dependent features from scratch. It lets you replace bodies and datums, and lets you reapply dependent features from the first bodies onto the second. The original features on the first bodies and datums are thus replaced by new features, while maintaining associativity with downstream features.

Uses for Replacement Features

This option can use in many ways. For example, you can use it to: Replace older versions of bodies imported from external systems to updated versions of the same bodies, without having to redo later modeling. Replace one free form surface with another modeled in a different way. Remodel a set of features in a body in a different way. Replace Features is not meant as a replacement for the Copy Feature, Paste Feature or any of the other Edit Feature options. It is intended as a way to make edits to a body based on its parent geometry. As such, it maintains associativity between features and bodies.

Replacing Features In this activity, you will replace the orange sheet body with the yellow sheet body and update the model.

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Replace Feature lets you replace one or more features on a body with another set of features from other bodies in the part.

Replacing Features Opening the Part Open part file fmf2_replace.prt from the fmf2 subdirectory, and start the Modeling application. The model contains a sheet body with other features attached to it. You will change the model, replacing the flat sheet with a curved sheet.

Replacing Features Starting the Feature Choose the Replace Feature icon The Replace Features dialog displays.

or Edit

Feature

Replace.

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The Filter option lets you mask for a type of object for selection. You can use Any, Sheet Body, Solid Body, Datum Plane, or Datum Axis.

Replacing Features Specifying the Body and Original Features

The Body/Datum step replace.

lets you select the body or datum whose features you wish to

Using the Body/Datum selection step

The Original Features

, select the orange body in the view.

step lets you select the original features that you want to replace.

1226 Original features can be a set of features on the same body, a datum plane feature, or a datum axis feature. Choose the Original Features selection step advance to this step.

or use the middle mouse button to

Retain Replacement Features lets you save the replacement features instead of deleting them. If this is toggled off, then the system will delete features that are replaced. Leave the Retain Replacement Features toggled on. The Features in Part list shows features that are part of the selected body. You can select any item in this list for original or replacement functions. The Features in Part list varies depending on which selection step is active. When the Original Features selection step is active the list contains all features of the body selected in the previous Body/Datum selection step, and which are available to be added to the Features to Replace listing. With the Replacement Features selection step the listing displays those features you can use to replace original features. You will replace the unparameterized feature (flat sheet). Select the first UNPARAMETERIZED_FEATURE(0) in the list. The flat sheet highlights.

Now, you can add it to the Features to Replace list. Choose the Add Feature icon

to add it to the list on the right.

The unparameterized feature is now located in the Features to Replace list box, and removed from the other list. You need to move the OFFSET(1) feature to the Features to Replace list. Select the OFFSET(1) in the Features in Part list.

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Choose the Add Feature icon

to add it to the list on the right.

Both features are listed in the Features to Restart.

Replacing Features Specifying Replacement Features

Replacement Features

lets you select features to be used as replacements for those that

you selected in the Original Features selection step. Replacement features can be a set of features on other bodies in the same part file, if the original feature is not a datum feature; or, a datum plane, if the original feature is a datum plane; or, a datum axis, if the original feature is a datum axis. You are now ready to specify the feature that will be replacing the unparameterized feature. Choose Replacement Features. The Features in Part now lists two features. You need to select both of the listed features and move them to the Replacement Features list box. Select the UNPARAMETERIZED_FEATURE (3) and choose the Add Feature icon. Select the OFFSET(4) feature and choose the Add Feature icon.

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Replacing Features Specifying the Parent Map and Completing the Change

The Parent Map option lets you select new parents for the children of the features you are replacing. You need to specify the parent mapping. Choose Parent Map. The dialog does not list any unresolved constraints, so you can just ok the dialog to continue editing the model. Choose OK. If no errors occur, the model updates. However, for this part file, an Edit during Update dialog displays, because certain objects of the trim and blend operations need to be respecified.

Replacing Features Respecifying the Trimmed Sheet Snapshot Curve The Edit During Update dialog displays an error updating the trimmed sheet feature.

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Select the Edit icon

on the Edit during Update dialog.

Select the Edit Parameter icon

on the next Edit During Update dialog.

The view displays the features for the respecification of the Trimmed Sheet operation.

The Trimmed Sheet dialog displays two selection steps: Trim Boundary, and Region. The Trim Boundary selection step respecify the trim boundary.

is active on the Trimmed Sheet dialog, so you need to

Use a Filter of Any. The system currently sees the white circular snapshot curve (edge) as the trim boundary. You need to deselect it first, and then you can select the new snapshot curve (edge). First shift and MB1 and select the white intersection snapshot curve to deselect it.

The white circle will now display as a green circle. Rotate the view slightly. An orange edge displays where there is an intersection of the cylindrical sheet and the unparameterized free form sheet. Select the orange snapshot edge that intersects the new free form sheet body, above the green intersection curve.

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Choose OK on the Trimmed Sheet dialog. Now, the Region selection step

is active.

Since a point was already selected, when the trim was originally created, you do not have to reselect it now. You will trim and keep the same general area. Choose OK on the Trimmed Sheet dialog. Choose OK on the small Edit During Update dialog.

Replacing Features Respecifying the Blend Snapshot Curve

Now, the Edit during Update dialog lists an error updating the blend feature. You need to respecify objects for the blend creation.

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Again, you need to edit the parameters of the blend, respecifying the blend edge.

Select the Edit icon

on the large Edit during Update dialog.

Select the Edit Parameter icon

on the small Edit During Update dialog.

The Edge Blend dialog displays. First shift and MB1 and select the white intersection curve to deselect it. (It will display as green after your selection.)

Now you need to specify the correct edge for the blend. Select the edge at the intersection of the free form sheet and the cylindrical sheet.

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Choose MB2 to OK the selection, and OK until the model updates. The original feature is replaced and the child features are replaced based on the Parent Map specifications.

Close all part files.

Knowledge Fusion Knowledge Fusion contains tools for capturing and manipulating engineering rules and design intent, so that you can add knowledge based engineering rules into the your design process.

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The rules extend beyond a purely geometric nature, and may involve engineering calculations, such as non-geometric physical properties, analysis results, sensitivity, physical properties, processes, and much more. A separate license is needed to run Knowledge Fusion. If you do not have access to this license, you can still read through this brief overview.

Creating a Simple Model Using Knowledge Fusion In this activity, you will create four lines, extrude them into a solid body, and at the location of the WCS, add a hole to the model. Remember, Knowledge Fusion requires a separate license.

Creating a Simple Model Using Knowledge Fusion Opening the Part Open part file fmf2_prim_1.prt from the fmf2 subdirectory, and start the Modeling application. You'll need to save the file in a writable directory. Choose File

Save As, key in a unique file name, and save it in a writable directory.

You can interactively program engineering rules by choosing Tools

Knowledge Fusion.

1234 Make the Knowledge Fusion toolbar visible and make sure that all icons are included in the toolbar. (You may need to toggle on Knowledge Fusion Toolbar on the Application and Modeling Toggles toolbars. Refer to the Unigraphics NX Essentials course for details on customizing the toolbars.) The toolbar displays.

Creating a Simple Model Using Knowledge Fusion Displaying the Knowledge Fusion Navigator

Choose the Knowledge Fusion Navigator icon or tab. The Knowledge Fusion Navigator window displays.

If you are running a under Windows, you can pin the display open.

Creating a Simple Model Using Knowledge Fusion Starting the First Line Object To create the first of four lines for the extrusion, you need to identify the child rule for the line, and then specify its parameters. Place the cursor on the root node in the Knowledge Fusion Navigator and using MB3, choose Add Child Rule. The Add Child Rule dialog displays.

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You need to specify a class next. The class contains objects (lines, arcs, body, etc.), each of which have default parameters that are needed to construct the geometry. You can choose objects from the User Class, or System Class, or from both. Use Both classes. Since each child object must have a unique name, you need specify one. In the Name field, for the rule name, key in line1. You can select any of the objects listed in the list box, and edit its parameters in the Input Parameters list box. You can see the various types of objects that are available by scrolling through the list below "Filter Setting". Because the object you will be creating is a line, you need to select the ug_line object from the list of objects in the classes. Select ug_line from the list under Filter String.

Creating a Simple Model Using Knowledge Fusion Specifying the First Line Start Point Now, the ug_line input parameters displays in the Input Parameters list box.

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Now, you need to change the ug_line parameters to create the desired line. For line objects, you need to specify the start and end points. This line will be 4 units long. It will be created so that when all four lines are complete, the WCS will be in the center of the rectangle formed by the four lines. First, you can modify the start point. In the Input Parameters list box, choose Start__Point (Point) to display it in the Rule for Parameter list box. Edit the rule to read Point(-2,2,0);.

The Apply Typing icon saves your edits into the Input Parameters list box and removes them from the editing area of the Rule for Parameter list box. The Cancel Typing icon clears the text from the Rule for Parameter list box, and does not save your edits.

Choose the Apply Typing icon

to complete the change.

The new start point parameters display in the Input Parameters list box.

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Creating a Simple Model Using Knowledge Fusion Specifying the First Line End Point Using the same technique, change the End_Point (Point) to read Point (2,2,0);. Choose the Apply Typing icon. The line start point and end point are complete.

You will use all other default parameters for this first line. To complete the line, you need to apply the input parameters. If you do not apply these changes, and you Cancel the editor dialog, the line will not be created. Apply the dialog.

Creating a Simple Model Using Knowledge Fusion The Attributes of the New Child Rule The new line is created, displayed in the view, and listed under the root.

You can see what attributes have been added by expanding the rule that you just added. Expand the line1 (ug_line) by clicking on the + (plus) sign. Expand the Attributes (ug_line) by clicking on the + (plus) sign. All the attributes of the line are listed. Some are defined, others are not.

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Collapse the lists by clicking on the two - (minus) signs. Cancel the Add Child Rule dialog.

Creating a Simple Model Using Knowledge Fusion Adding the Second Line You need to repeat the procedure, and create the second line to be extruded into the block. Choose root to highlight it in the Knowledge Fusion Navigator. Using MB3 on the root, choose Add Child Rule to create the next line. In the Name field, for the rule name, key in line2. Choose ug_line from the Filter String list. Choose the Start_Point (Point) to display it in the Rule for Parameter list box. Edit it to read Point(-2,2,0); and choose Apply Typing

.

Edit the End_Point to read Point(-2,-2,0); and choose Apply Typing. Choose Apply on the Add Child Rule dialog. Two lines now display in the view. You may want to move the dialog to one side of the graphics area to see this display.

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Creating a Simple Model Using Knowledge Fusion Adding the Third Line

You need to create the last two lines to form a square. In the Name field of the Add Child Rule dialog, enter line3 as the name. Choose ug_line from the Filter String list. Change the Start_Point to Point(-2,-2,0); and choose Apply Typing. Change the End_Point to Point(2,-,2,0) and choose Apply Typing. OK the Knowledge Fusion Navigator. Three lines display in the view.

Creating a Simple Model Using Knowledge Fusion Adding the Last Line You need to repeat the procedure to create the last line for the extruded body. This will connect the endpoints of the first and third line, closing the string. Choose root and choose Add Child Rule. In the Name field, for the rule name, enter line4. Choose ug_line from the Filter String list. Change the Start_Point to Point(2,-2,0); and apply the typing. Change the End_Point to Point(2,2,0); and apply the typing. Choose OK on the Knowledge Fusion Navigator. All four lines are complete.

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The four lines are listed in the left side of the Knowledge Fusion Navigator dialog. You are now ready to extrude the string into a solid body. Save your part file.

Creating a Simple Model Using Knowledge Fusion Specifying a ug_extruded Child Rule To continue adding child rules, you need to choose root again.

Display the Knowledge Fusion Navigator. Choose root, and choose Add Child Rule. The four curves are listed under the Attributes of the root.

Now, you need to create a child rule that extrudes these curves into a block. Use the class ug_extruded and name the child extr. The input parameters display in the lower list box. Choose Profile (List) .

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Creating a Simple Model Using Knowledge Fusion Adding the First Line to the Rule for Parameter You need to specify the objects that will form the profile for the extruded body. You can simply select the objects and add a comma at the end of the object. In the Knowledge Fusion Navigator window, place your cursor over line1 (ug_line). Press MB3 and choose Reference.

The selected line1 now is included in the Rule for Parameter. Type in a comma, using your keyboard. You have completed the first line segment for the string of curves that you'll use in the extruded feature.

Creating a Simple Model Using Knowledge Fusion Adding Three More Lines to the Rule for Parameter You need to add line2, line3, and line4. Place your cursor on line2, press MB3 and choose Reference. Key in a comma at the end of the current Rule for Parameter statement, placing it just before the closing bracket. Repeat this process for line3. You do not need to use the comma after "line4:" Place your cursor on line4, press MB3 and choose Reference. (No comma is needed after

1242 the last line.) Remember, commas must separate each line number. Now, you need to save the profile rule.

Choose Apply Typing.

Creating a Simple Model Using Knowledge Fusion Completing the Extruded Body You could change the start limit, end limit, taper angle, and other input parameters of the extruded feature, but for this activity, you will use all the defaults. Therefore, the block will start at zero and end at one, making the block one inch tall. No taper will exist. Choose Apply on the dialog. Cancel the Add Child Rule dialog. The extr (ug_extruded) rule has been added to the list of objects under root.

Choose root. The block (extruded body) is displayed in the view. You can move the Knowledge Fusion Navigator dialog to see the solid body.

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Creating a Simple Model Using Knowledge Fusion Adding a Hole to the Model The model needs a simple through hole with a diameter of 3/4 inch. You can use a cylinder and subtract it from the solid model. Using Add Child Rule, name the new child rule hole1 and use the class ug_cylinder.

Choose the Diameter (Number) parameter, change it to .75; and choose the Apply Typing icon.

1244 Choose the Operation (Name) parameter, change it to Subtract;, and choose the Apply Typing icon. Choose the Target (List) Input Parameters, place the cursor over extr (ug_extruded) and use MB3 to select Reference. Notice that the origin is at (0,0,0), which is at the WCS. Choose Apply Typing. Choose Apply on the dialog, then Cancel the dialog. The model is complete. The hole and the block have been created at the location of the WCS.

Save your part file.

Creating a Simple Model Using Knowledge Fusion Examining the Knowledge Fusion File When you create a model using Knowledge Fusion Navigator dialog, you are generating an ASCII text file with the extension of *.dfa.

Choose the Knowledge Fusion Navigator

icon again.

To view the *.dfa file for the current part, you can list rules for the root.

1245 Highlight root and press MB3

List Rules.

The Information window displays the text contained in the dfa file.

This dfa file contains all rules and parameters of created objects for the current part file. All dfa files can be edited in an ASCII text editor, or edited through Unigraphics NX Knowledge Fusion. Parameters can be edited by selecting the desired object and editing the Input Parameters.

Creating a Simple Model Using Knowledge Fusion Examining the Model You can use the Knowledge Fusion Navigator, Information on features, the Model Navigator, or many other tools to find information about the model that has been created using Knowledge Fusion. Use the Model Navigator to view the features in this model.

The extruded body and cylinder feature is displayed. Use Information

Feature to see the feature list, which includes the same two features.

1246 Then, cancel the dialog. Use Tools Expression to see the expressions listed, which you created using Knowledge Fusion. Then cancel the dialog. Cancel all dialogs. Close the part file.

Additional Projects This section provides extra modeling projects for you to work through. They will provide you with a little more practice in Unigraphics NX.

Creating a Mounting Bar In this activity, you will create a mounting bar.

This metric part is a bar of metal with a series of smaller simple holes drilled through it. The larger holes are counterbored holes. To complete this project quickly, you should be familiar with the following features. Block Hole Instance -

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Creating a Mounting Bar Methods Used in this Project In this activity, you will create this mounting bar.

In this project you will do the following. Create a block.

Create two types of holes.

Array the two holes across the block.

Create a small tooling hole at the right end of the block.

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And finish by relating the number of holes to the length of the block in order to let the number of holes determine the length of the bar.

Creating a Mounting Bar Dimensions of the Part These are the overall dimensions of this part (in millimeters).

The smaller holes go completely through the part. The larger holes are countersunk holes, and also go through the part.

Creating a Mounting Bar Design Intent If this were used to mount electrical equipment, one set of holes might be for mounting the bar to the equipment, the other set for mounting equipment to the bar.

1249 You want the part to be adaptable to change. That is, if you change the number of holes in the part, you want the length of the bar to lengthen or shorten automatically. But you want the thickness and the width to remain unchanged.

Creating a Mounting Bar Starting a New Metric Part File Open the part file standard_mm.prt from the fmf2 subdirectory; or, you can start a new part file in millimeters, using a part file name such as bar_1.) The standard part file uses the following layer standards: Solid geometry on layers 1 through 20. Sketch geometry on layers 21 to 40 Curve geometry on layers 41 to 60 Reference geometry on layers 61 to 80 Sheet bodies on layers 81 to 100 Drafting objects on layers 101 to 120 Start the Modeling application.

Creating a Mounting Bar Modeling the Basic Shape of the Part Your first task is to model the basic shape of the part. One way to do this is to begin with a block solid.

Create a block with these dimensions. Place its lower, front, left corner at the origin of the

1250 WCS.

Choose the Block icon

or Insert

Form Feature

Block.

Use the Origin, Edge Lengths method. Key in the parameters of this feature ( XC = 608, YC = 19, ZC = 42) and choose OK. Change the display to Gray Thin Hidden Edges.

Creating a Mounting Bar Creating the First Hole You can place the first through hole near the left end of the block.

On the front face of the block, create a hole that goes all the way through the solid. Choose the Hole icon

or Insert

Form Feature

Hole.

Use the Simple option. Key in the diameter of the hole (16.0).

For the planar placement face For the thru face

, select the front face of the block.

, select the back face of the block.

Use two perpendicular constraints to position the hole at this location.

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Use the Perpendicular positioning icon. For the first perpendicular constraint, select the left vertical edge of the block.

Key in the distance (38.0) between the left edge and the center of the hole. Use the Perpendicular icon again. For the second perpendicular constraint, select the lower horizontal edge of the block. Key in the distance (25.0) between the lower edge and the center of the hole.

Creating a Mounting Bar Creating the Counterbored Hole The other type of hole that you will need on this part is a through counterbored hole.

You know that you will need seven of each type of hole along this bar. So you decide to create this counterbored hole before you create the array. You will want to place the counterbored hole near the simple hole.

Create a counterbored thru hole to the right of the simple hole.

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Choose the Hole icon. Choose Counterbore. Key in the parameters of this feature (21, 12.5, 12.5).

For the planar placement face For the thru face

, select the front face of the block.

, select the back face of the block.

Creating a Mounting Bar Positioning the Counterbored Hole Use the first hole to position this counterbored hole at this location. (Use a Horizontal and a Vertical constraint.) Use the Horizontal icon. For the horizontal reference, select the lower front edge of the block. For the target object, select the first hole. On the Set Arc Position dialog, choose the Arc Center option. On the dialog, key in the horizontal distance (32.0). For the vertical positioning constraint, choose the Vertical icon. For the target object, select the lower front edge of the block. Key in the vertical distance (19.0).

Creating a Mounting Bar Preparing to Create the Other Holes On this part, you need holes across the length of the mounting bar.

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You have already planned to array the two holes together along the length of the bar. To do this correctly, you will first need to orient the WCS so that its XY plane coincides with the top face of the bar. This will let you define a positive X value along the length of the bar, and a Y value vertically on the bar. Rotate the WCS to this orientation (or use edges to orient it). Choose WCS Rotate. On the Rotate WCS dialog, choose the +XC Axis option. Be sure the Angle value is set to 90. OK the dialog.

Creating a Mounting Bar Creating the Other Holes Along the Bar You will need seven sets of holes along the length of the mounting bar.

Make an array of both holes that creates a total of seven sets of holes along the bar. (NOTE: Only the first hole will be displayed in the tool image). Choose the Instance Feature icon Instance.

or Insert

Feature Operation

1254 On the Instance dialog, use the Rectangular Array option. Select both hole features. Use the General method. Key in the number of instances along the XC = 7, the Offset along XC = 76, the number of instances along YC = 1, and the YC Offset = 0.

On the dialog, choose Yes if the array is correct.

Creating a Mounting Bar Creating the Tooling Hole To finish up the modeling of this part, you need a small tooling through hole at the right end of the bar.

Create one hole that goes through the part. Choose the Hole icon. Choose the Simple option. Key in the diameter (9) of the hole.

For the planar placement face right end. For the thru face

, select the front face of the block near its

, select the back face of the block.

Use two perpendicular constraints to position it at this location. (Be sure to use the top

1255 edge and the right edge.) Choose the Perpendicular icon. For the first perpendicular constraint, select the right vertical edge of the block. On the dialog, key in the distance 28 between the left edge and the center of the hole. Choose the Perpendicular icon again. For the second perpendicular constraint, select the upper horizontal edge of the block. Key in the distance of 12.5 between the lower edge and the center of the hole.

Creating a Mounting Bar Relating the Length of the Part to the Number of Holes The part is finished, but you can make it a more useful part by finding the expressions that will let you change the number of holes and have the length of the part stretch or shrink accordingly. In order to be sure you are looking at the correct expression numbers, you can work with a specific part. Open part file metric_bar.prt from the fmf2 subdirectory. This part was created according to the same instructions you followed for this project.

Creating a Mounting Bar Adding the First New Expressions You will need to add two expressions to those already created. The first will let you key in a specific number of holes. The second will define a specific distance between the instances of holes. Be sure you are in the Modeling application. Use Tools

Expression to display the Edit Expressions dialog.

In the text field, above "Value=", key in N=7.

1256 Apply the dialog. This new expression appears alphabetically at the top of the list box.

Creating a Mounting Bar Adding the Second New Expression This second expression will be a formula that includes: the expression that defines the distance between the end of the bar and the first hole.

the expression that defines the distance between instances.

plus a constant value that will place the right end of the bar a specific distance away from the last instance.

You can begin by finding the expression in the array feature for the number of holes along the X value of the array. Choose Information

Expression

List All By Reference.

Because two features were instanced at the same time in the part file, this is info on RECTANGULAR ARRAY(3) and RECTANGULAR ARRAY(4). But you will find that each array feature has the same expression numbers.

1257 The number of the expression for the "Number Along X" is "p11". You also find that expression "p12" defines the distance value between the instances in the array, the "Positioning Dimension Distance". You can create a "length of the bar" formula that will combine these three values.

Create a second expression that will relate the number of holes to the length of the part: L = p12 + ( p11 * p12 ) + 48 In the editor field, above "Value =", key in L = p12 + ( p11 * p12 ) + 48 and press Enter.

This new expression appears alphabetically at the top of the list box.

Creating a Mounting Bar Changing the Length of the Bar and Number of Holes Your final step is to change the values of the two "number" and "length" expressions you included in the formula. Set the expression that defines the length of the block along X to the new "Length" expression: p0=L Choose p0=608. In the editor field, above "Value=", change 608 to L and press Enter.

Now here is the key expression. Right now expressions "N" and "p11" both equal seven. You want expression "p11" to use the number of holes value that you key in on expression "N". Change expression "p11" to this: p11=N Choose p11=7. In the editor field, above "Value=", change 7 to N and press Enter.

1258 Apply these values on the Expressions dialog. The system warns you that expression "p11" is "used by" another expression. You are ready to check your work. Right now there are seven sets of holes along the bar. Change the N value to 5 and OK the dialog. Choose N=7. In the editor field, above "Value=", change 7 to 5 and press Enter. Choose Apply. Check the results on the part. The bar should be shorter, and have five sets of holes in the instance array. Close all parts.

Creating a Vessel In this activity, you will create this vessel.

This is a vessel with four feet on its bottom. There is also a small hole drilled through the bottom of the vessel. To complete this project quickly, you should be familiar with the following features. (Review these lessons if you are unfamiliar with these features.) Cylinder Edge Blend Hollow -

1259

Datum Plane Boss Instance Feature Hole -

Creating a Vessel Methods Used in this Project You will create this vessel.

To create this vessel, you will complete the following. Begin with a cylinder.

Round off the bottom with a blend.

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Hollow out the inside of the cylinder.

Add four small feet to the bottom.

And, finally, place a hole

in the bottom.

Creating a Vessel Dimensions of the Part These are the overall dimensions of this part (in millimeters).

1261

Creating a Vessel Design Intent For this part you need to be able to vary: the diameter of the vessel. the wall thickness of the vessel. the angular location of the small hole. the size and placement of the feet.

Creating a Vessel Starting a New Part File (Metric) Open the part file standard_mm.prt from the fmf2 subdirectory, or start a new part file in millimeters. The standard part file uses the following layer standards:

1262 Solid geometry on layers 1 through 20. Sketch geometry on layers 21 to 40 Curve geometry on layers 41 to 60 Reference geometry on layers 61 to 80 Sheet bodies on layers 81 to 100 Drafting objects on layers 101 to 120 Start the Modeling application.

Creating a Vessel Creating the Basic Shape of the Vessel You can use a cylinder feature to form the basic shape of this part.

Create a cylinder. Place its axis at the 0, 0, 0 position of the current location of the WCS. Choose the Cylinder icon or Insert Form Feature Cylinder. Use the Diameter, Height method. Align the axis of the cylinder along the ZC axis of the WCS. Specify the parameters of this feature (diameter of 600 and height of 300). Place the origin of the cylinder at the 0, 0, 0 location of the WCS. Place the center of the cylinder at the origin of the WCS. Fit the view.

1263

Creating a Vessel Rounding Off the Bottom of the Vessel The vessel has a rounded bottom edge.

Create a blend on the bottom edge of the cylinder. Choose the Edge Blend icon Blend.

or Insert

Feature Operation

You need the radius of the blend to be 25. Enter the default radius value of 25.0 for the blend. Select the bottom edge of the cylinder, then OK the dialog.

Creating a Vessel Hollowing the Model Hollowing out the cylinder will create the true shape of the vessel.

Edge

1264 Create a hollow feature with a wall thickness of 10.0. Choose the Hollow icon

or Insert

Feature Operation

Hollow.

Be sure the Type if set to Face. Use the Pierced Face selection step. Select top face (to be pierced) of the cylinder.

Enter the Default Thickness value for the wall (10.0). OK the dialog until the model updates.

Creating a Vessel Preparing to Add Feet to the Vessel To place the feet, you will need datum planes through the part that are perpendicular to each other

You will want to have this datum geometry on its own layer. Make layer 61 the work layer. Create a datum plane through the axis of this part.

1265

Choose the Datum Plane icon or Insert Plane. Select the cylindrical face of the model. Choose OK.

Form Feature

Datum

Create another datum plane through the axis of the part and perpendicular to the first. Choose the Datum Plane icon or Insert Form Feature Plane. Select the axis of the cylindrical face. Select the datum plane Check that the angle value is 90, and choose OK.

Datum

You should have two datum planes at right angles to each other, and both through the center of the cylinder.

Creating a Vessel Creating a Datum Axis When you are ready to instance the feet, you will want to have a datum axis through the axis of the cylinder.

Be sure layer 61 is still the work layer. Create a datum axis through the cylinder. Choose the Datum Axis icon Select the cylindrical face. Choose OK.

or Insert

Form Feature

Datum Axis.

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Creating a Vessel Preparing to Add the First Foot You can use a tapered pad to create the first foot on the bottom of the vessel. It does not really matter where you begin.

You may want to change to a BOTTOM view, then slightly rotate it so that you will be able to select the datum axis later.

Creating a Vessel Adding the First Foot Change the work layer back to layer 1. Create one boss on the bottom of the vessel. Choose the Boss icon or Insert Form Feature Select the bottom face of the part. Key in the parameters of this feature (50, 20, 4).

Boss.

1267 Position this hole on the "YC" datum plane and perpendicular to the "XC" datum plane. Use the Point onto Line icon. For the target edge, select the datum plane along the YC axis. Use the Perpendicular icon. For the target edge, select the datum plane along the XC axis. Key in the distance value (230) from the datum plane to the hole, and OK the dialog.

Creating a Vessel Adding the Rest of the Feet Now that you have the first foot, you can add the rest.

To create the four feet on the bottom of the vessel, create a circular array of the boss. After you create them, rotate the vessel around to check the results. Choose the Instance Feature icon or Insert Feature Operation Instance. Choose Circular Array. Choose the boss feature, then OK the dialog. Use the General method. Key in the total number of instances (4) in the array and the angle (90) between

1268 instances, then OK the dialog. For the rotation axis, use the Datum Axis method. Select the datum axis, then OK the dialog. If the tool display looks correct, choose Yes on the Create Instances dialog.

Creating a Vessel Planning for the Creation of a Hole in the Bottom of the Vessel Your last task is to place a small hole in the bottom of the vessel. It must be near the rim of the vessel but must miss the foot.

Thinking ahead, you plan to position this hole by using a datum plane that is canted 15 degrees off of the "vertical" datum plane. Then, to position the hole a certain distance from the center of the part, you will need to use another datum plane that is perpendicular to the canted one. You will want these datum planes to be on their own layer. Make layer 62 the work layer. To help keep yourself oriented, you might want to return to a trimetric view.

1269

Creating a Vessel Creating the Canted Datum Plane Use the "YC" datum plane to create a datum plane through the axis of the part, but at an angle of 15 degrees to it. Choose the Datum Plane icon or Insert Form Feature Plane. Select the axis of the cylindrical face of the model. Select the "YC" datum plane Key in an angle value of 15. Choose OK.

Datum

Creating a Vessel Creating the Final Datum Plane

You'll use this final datum plane to position the hole a certain distance from the center of the part. Optional: Make layer 61 invisible. Create a fourth datum plane through the part at 90 degrees to the third datum plane. Select the axis of the cylindrical face again. Select the canted datum plane. Key in the Angle of 90. Choose OK.

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Creating a Vessel Creating the Hole Now you are ready to place the hole in the part. It must penetrate the thickness of the vessel.

Make layer 1 the work layer. You might also want to rotate the part so you are looking down into it. (Just be sure you will be able to easily select the bottom face of the part.) Create a hole that goes all the way through the part. Indicate a location for it near its eventual position. Choose the Hole icon

or Insert

Choose the Simple option. Key in the diameter of the hole (20).

Form Feature

Hole.

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For the planar placement face For the thru face

, select the inside bottom face of the vessel.

, select the outside bottom face.

Use the two canted datum planes to position it. Use the Point onto Line hole at a distance of 250.

and Perpendicular

methods to position the

Make all layers except layer 1 Invisible.

Creating a Vessel Modifying the Part There are many dimensions you can modify on this part without "breaking" it. Of course there is a limit to the amount of variation you can introduce. You can vary these dimensions: the diameter of the vessel. the wall thickness of the vessel. the angle of the small hole. the size and placement of the feet.

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Creating a Simple Collet In this activity, you will be creating this collet model.

This is a small collet is designed to be clamped onto a flat surface with four bolts. The top portion is tapered, and there is a counterbored hole through the axis of this part. To complete this project quickly, you should be familiar with the following features. (Review these lessons if you are unfamiliar with these features.) Cylinder Boss Hole Datum Plane Datum Axis -

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Instance Feature Edge Blend -

Creating a Simple Collet Methods Used in this Project You will be creating the following collet model.

There are several different ways you can use features to model this part. In this project you will: Use a cylinder

Add a tapered boss

to create the rim of the collet.

to create the vertical portion.

Drill the internal counterbored hole.

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Add datum planes , and one hole on the rim (whose center is a little outside the circumference of the rim).

Add the other three holes around the rim.

And finish with some blends.

Creating a Simple Collet Dimensions of the Part These are the overall dimensions of this part (in millimeters).

1275

Creating a Simple Collet Design Intent

You need to be able to vary this part in several ways: Change the size and taper angle on the boss Change the dimensions of the central counterbored hole Change the size and number of the holes around the rim

Creating a Simple Collet Starting a New Part File (Metric) Open part file standard_mm.prt from the fmf2 subdirectory.

1276 The standard part file uses the following layer standards: Solid geometry on layers 1 through 20. Sketch geometry on layers 21 to 40 Curve geometry on layers 41 to 60 Reference geometry on layers 61 to 80 Sheet bodies on layers 81 to 100 Drafting objects on layers 101 to 120 Start the Modeling application.

Creating a Simple Collet Creating the Base Feature of the Collet You can start with a cylinder.

Create a cylinder. Place its axis at the origin of the WCS. Choose the Cylinder icon or Insert Form Feature Cylinder. Use the Diameter, Height method. Align the axis of the cylinder along the ZC axis of the WCS. Key in the parameters of the cylinder (diameter of 125 and height of 25). Place the origin of the cylinder at the 0, 0, 0 location of the WCS.

Creating a Simple Collet Adding a Boss to the Cylinder One way to construct the upper part of this part is to use a tapered boss feature so that the two features will be associated.

1277

Create a tapered boss on the top face of the cylinder. Choose the Boss icon or Insert Form Feature Key in the parameters of this feature (70, 50, 9). For the placement face, select the top face of the cylinder.

Boss.

Position the boss at the center of the top face of the cylinder. Choose the Point onto Point icon. Select the top edge of the cylinder. Choose the Arc Center option.

Creating a Simple Collet Creating the Internal Holes There is one hole that goes all the way through the collet as well as a large but shallow hole bored into the bottom of the collet.

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The easiest way to create these holes is to use a counterbored hole feature. Use the bottom face of the cylinder to create a counterbored hole. Make it go completely through the part. Choose the Hole icon

or Insert

Form Feature

Hole.

Choose the Counterbore option. Key in the parameters of this feature (76, 12.5, 38).

For the planar placement face, select the bottom face of the cylinder. For the thru face, select the top face of the tapered boss. Position the axis of the counterbored hole along the axis of the cylinder. Choose the Point onto Point icon. Select the bottom edge of the cylinder. Choose the Arc Center option.

Creating a Simple Collet Creating the Reference Geometry One of your next tasks will be to create four partial holes around the rim of the collet.

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So this is a good time to create two datum planes through the center of the cylinder that you can use to position the first hole. Also, you want to place these datum planes on a layer reserved for reference geometry. Change the work layer to layer 61. Create a datum plane through the cylinder axis. Choose the Datum Plane icon or Insert Form Feature Plane. Select the cylindrical face of the cylinder feature. Choose OK.

Datum

Create another datum plane through the cylinder axis, but perpendicular to the first. Select the vertical datum plane. Select the axis of the boss. Be sure the angle value is 90 degrees. Choose OK.

Creating a Simple Collet Creating the Datum Axis You also plan to use a circular array to create the holes around the rim of the collet. So you can create a datum axis now that you will use later. You are still working on layer 61. Create a datum axis through the center of the cylinder solid.

1280

Choose the Datum Axis icon Select the cylindrical face. Choose OK.

or Insert

Form Feature

Datum Axis.

Creating a Simple Collet Creating the First Hole on the Rim The centers of the holes around the rim of the collet are not on the circumference of the cylinder, but are placed a little further out.

You will need to use both datum planes to position this first hole after you create it. Change the work layer back to layer 1. Create a simple thru hole on the top face of the cylinder. Indicate a location near the front edge of the part. Choose the Hole icon

or Insert

Form Feature

Hole.

Choose the Simple option. On the Simple Hole dialog, key in the diameter of the hole (25).

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For the planar placement face, select the top face of the cylinder. (Do not pick up a datum plane by mistake.) For the thru face, select the bottom face of the cylinder. Position this hole on the "YC" datum plane and at the required distance perpendicular to the "XC" datum plane. Use the Point onto Line icon. For the target edge, select the datum plane along the YC axis. Use the Perpendicular icon. For the target edge, select the datum plane along the XC axis. Key in the distance value (66) from the datum plane.

Creating a Simple Collet Creating the Four Holes Around the Rim of the Collet You have planned all along to create four holes around the rim of the collet by using a circular array.

1282

Array the other holes around the rim of the collet. Choose the Instance Feature icon or Insert Feature Operation Instance. Choose Circular Array. On the dialog, choose the last simple hole feature, then OK the dialog. On the Instance dialog, use the General method. Key in the total number of instances (4) in the array and the angle (90) between instances, then OK the dialog. For the rotation axis, use the Datum Axis method. Choose the datum axis, then OK the dialog. If the tool display looks correct, choose Yes on the Create Instances dialog.

Creating a Simple Collet Adding Blends To finish this part you would like to round some edges.

1283 Add a blend to the top edge of the boss and to the join between the cylinder and the boss. Choose the Edge Blend icon or Insert Blend. Be sure the blend type is Edge. Key in the default radius (2.0) for the blend. Select the two edges, and OK the dialog.

Creating a Simple Collet Variations on the Part You could vary this part in several ways: change the taper angle on the boss change the diameter of boss change the dimensions of the counterbored hole change the size of the holes in the rim change the number of holes in the array

Feature Operation

Edge

1284

Creating a Pivot Plate In this activity, you will create a pivot plate.

This is a plate with a pivot boss on its underside. There are several different kinds of mounting holes in the plate. To complete this project quickly, you should be familiar with the following features. (Review these lessons if you are unfamiliar with these features.) Block Datum Plane Pad Pocket Boss Hole Edge Blend Edge Chamfer -

1285

Creating a Pivot Plate Methods Used in this Project You will create this pivot plate.

In this project you will complete the following. Begin with a block

Add a pad

feature to model the basic shape of this part

under the block to create the pivot.

Use a pocket feature

Create a hole

Add a tooling hole

to cut a chunk of material out of the front of the block.

through the pad under the block.

and three counterbored holes to the model.

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Chamfer

the front and back edges of the pad.

And finish by blending

various edges.

Creating a Pivot Plate Dimensions of the Part These are the overall dimensions of this part (in millimeters).

A large hole goes through the pivot boss underneath the plate.

1287

Creating a Pivot Plate Design Intent

For this part you need to be able to: Change the length of the plate, but keep the counterbored holes (and the tool hole) the same distance from the edges. Change the height of the plate but still maintain the cutout in the front of the plate. Change the dimensions of the cut out area but keep it centered between the left and right edges of the part. Change the dimensions of the pivot boss or the hole that goes through it, but keep the hole centered within the structure. Change the amount of chamfer on the pivot boss. Change the depth of the cutout in the front of the part.

1288

Creating a Pivot Plate Starting a New Part File (Metric) Open the part file standard_mm.prt from the fmf2 subdirectory. The standard part file uses the following layer standards: Solid geometry on layers 1 through 20. Sketch geometry on layers 21 to 40 Curve geometry on layers 41 to 60 Reference geometry on layers 61 to 80 Sheet bodies on layers 81 to 100 Drafting objects on layers 101 to 120 Start the Modeling application.

Creating a Pivot Plate Creating the Plate Portion of this Part The most logical solid to begin with for this part is the plate portion, which you can model with a block feature.

Create a block feature. Position it at the 0, 0, 0 location of the WCS. Choose the Block icon

or Insert

Form Feature

Block.

Use the Origin, Edge Lengths method. Key in the parameters of this feature (480, 260, 50) and OK the dialog.

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Fit the view.

Creating a Pivot Plate Preparing to Create the Pivot You know that you will want to center the pivot between the left and right sides of the plate (block). You can use a datum plane that is centered between the left and right faces of the block to do this. You will want to have this datum plane on its own layer. Make layer 61 the work layer. Create a datum plane centered between the left and right ends of the block feature. Choose the Datum Plane icon or Insert Plane. Select the left vertical face of the block feature. Select the right vertical face". Choose OK.

Form Feature

Datum

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Creating a Pivot Plate Creating the Structure for the Pivot The pivot is on the underside of the plate (block).

Create a rectangular shaped pad on the bottom face of the block feature. Make its horizontal (length) parameter parallel to the XC axis. Choose the Pad icon or Insert Form Feature Pad. Use the Rectangular method. For the planer placement face, select the bottom face of the block. For the horizontal reference, select the top front edge of the block (or any edge parallel to the XC axis). Key in the parameters of this feature (200, 100, 100, 0, 0).

Creating a Pivot Plate Positioning the Rectangular Pad Use the datum plane to position the pad at center location between the left and right sides of the plate. Then use the back edge of the block and the top back edge of the pad to define the distance from the back of the plate to the back of the pad. Choose the Line onto Line icon. Select the datum plane. Select the back-to-front dashed centerline on the pad tool. Choose the Perpendicular icon. Select the lower back edge of the plate.

1291 Select the top back edge of the pad tool. Key in the distance value (55). OK the dialog.

With the pad in place, your model should look like this.

Creating a Pivot Plate Preparing to Create the Cutout at the Front of the Plate Your next step will be to cut a rectangular shape out of the front of the plate.

You plan to use a pocket feature to do this. You will also want to center this feature along the front face of the plate. You already have one datum plane centered between the left and right faces of this part. The next datum plane can be centered between the top and bottom faces of the plane. You can create this next datum plane on the same layer as the first. Be sure that layer 61 is still the work layer. Create a datum plane centered between the top and bottom faces of the block feature.

1292

Choose the Datum Plane icon or Insert Form Feature Plane. Select the top face of the block feature. Select the bottom face of the block and choose OK. Fit the view.

Datum

Creating a Pivot Plate Creating the Cutout at the Front of the Plate Now you are ready to create the cutout. Create a rectangular pocket on the front face of the block feature. Make its horizontal (X length) parameter parallel with the XC axis. Use a width (Y length) that will assure that the material in the block feature will still be removed even if its height is made larger. Choose the Pocket icon or Insert Form Feature Pocket. Use the Rectangular method. For the planar placement face, select the front face of the block. For the horizontal reference, select the top front edge of the block. Enter the parameters of this feature (200, 75, 50, 0, 0, 0).

Center this pocket feature on the front face of the block. Be careful not to overconstrain its position. Choose the Line onto Line icon. Select the horizontal (top/bottom centered) datum plane. Select the horizontal centerline on the pocket tool.

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Select the Point onto Line icon. Select the vertical datum plane. Select the vertical centerline on the pocket tool.

With the pocket in place, your model should now look like this.

Creating a Pivot Plate Preparing to Create the Hole Through the Pivot You will need to create a hole through the pad under the plate. You will want to position it in the center of the pad (looking from its right end).

You can use two datum planes to do this. You would like both of these datum planes to be on their own layer. Make layer 62 the work layer, then make the datum planes on layer 61 invisible. Create a datum plane that is centered between the bottom face of the block and the bottom face of the pad.

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Choose the Datum Plane icon or Insert Form Feature Plane. Select the bottom face of the block feature. Select the bottom face of the pad feature and choose OK.

Datum

Create another datum plane that is centered between the front and back faces of the pad. Choose the Datum Plane icon or Insert Form Feature Plane. Select the front face of the pad feature. Select the back face of the pad feature and choose OK.

Datum

Creating a Pivot Plate Creating the Pivot Hole Now you are ready to create the hole through the pad.

Create a hole on right face of the pad. Be sure it goes all the way through the pad. Choose the Hole icon Choose the Simple option. Use a hole diameter of 60.

or Insert

Form Feature

Hole.

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For the placement face, select the right face of the pad. For the thru face, select the left face of the pad. Position it in the center of the right end of the pad. Choose the Point onto Line icon. Select the vertical datum plane that is centered in the pad. Choose the Point onto Line icon again. Select the horizontal datum plane that is centered in the pad.

Creating a Pivot Plate Creating a Tooling Hole You need to create a small hole through the front left side of the plate.

You will not need to leave the datum planes visible. Make layer 1 the work layer, then make the datum planes on layer 62 invisible. Create this simple hole at the left side of the part. You can place it on the top face of the block. Choose the Hole icon

or Insert

Form Feature

Hole.

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Choose the Simple option. Make the hole diameter 12.5.

For the placement face, select the top face of the block. For the thru face, select the bottom face of the block. Position the hole at this location on the block. Choose the Perpendicular icon. Select the bottom front edge of the block. Key in the distance value (32). Choose the Perpendicular icon again. Select the bottom left edge line of the block. Key in the distance value (32).

Creating a Pivot Plate Creating the First Counterbored Hole There are three counterbored holes that you must add to this part.

1297 Each will be drilled completely through the plate from the bottom face.

Create a counterbored hole on the bottom face of the block near its front left side. Choose the Hole icon

or Insert

Form Feature

Hole.

Choose the Counterbore option. Key in the parameters of this feature (35, 18, 12.5).

For the placement face, select the bottom face of the block. For the thru face, select the top face of the block. Position the hole at this location on the left side of the block. Choose the Perpendicular icon. Select the bottom front edge of the block. Key in the distance value (70). Choose the Perpendicular icon again. Select the bottom left edge of the block. Key in the distance value (70).

Creating a Pivot Plate Creating the Second Counterbored Hole Create a similar counterbored hole on the bottom right face of the block.

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Choose the Hole icon

or Insert

Form Feature

Choose the Counterbore option. Key in the parameters of this feature (35, 18, 12.5). For the placement face, select the bottom face of the block. For the thru face, select the top face of the block. Position the hole at this location on the right side of the block.

Choose the Perpendicular icon. Select the bottom front edge line of the block. Key in the distance value (70). Choose the Perpendicular icon again. Select the bottom right edge line of the block. Key in the distance value (70).

Creating a Pivot Plate Creating the Third Counterbored Hole The last counterbored hole is near the back of the part.

Hole.

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To position this counterbored hole, you will want to be able to use the datum plane centered between the left and right faces of the block. Make the two datum planes on layer 61 selectable. Create a third counterbored hole on the bottom face of the block with the same parameters as the other two.

Choose the Hole icon

or Insert

Form Feature

Hole.

Choose the Counterbore option. Key in the parameters of this feature (35, 18, 12.5). For the placement face, select the bottom face of the block. For the thru face, select the top face of the block. Position the hole at this location near the back side of the part. Keep it centered between the left and right sides of the block. Choose the Point onto Line icon. Select the "centered right/left" datum plane. Choose the Perpendicular icon. Select the back bottom edge of the block feature. Key in the distance value (28). OK the dialog.

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Creating a Pivot Plate Chamfering the Edges of the Pivot The pivot boss needs to have its two lower edges chamfered.

If you want, make the two datum planes on layer 61 invisible again. Chamfer the front and back bottom edges of the pad. Choose the Edge Chamfer icon or Insert Chamfer. Use the Single Offset method. Select the front and back bottom edges of the pad. Key in the parameter (20) of this feature. OK the dialog.

Feature Operation

1301

Creating a Pivot Plate Blending Edges There are many edges in this part that will be rounded as part of the casting process.

Blend these vertical edges with a 6 mm radius blend. Choose the Edge Blend icon or Insert Feature Operation Edge Blend. On the Edge Blend dialog, be sure the blend type is Edge. Key in the default radius of the blend (6 mm). Select each edge around the plate portion of this part that you want to blend. Apply the dialog.

Blend the tangent edges all the way around the bottom edges of the plate (block). Use the same blend radius.

Blend all of the edges around the pad under the block with the same radius blend.

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Creating a Pivot Plate Modifying the Part There are many dimensions you can modify on this part without "breaking" it. Of course there is a limit to the amount of variation you can introduce. You can vary these dimensions: If you change the length of the plate, all of the features positioned on the "center" datum planes will remain centered in the plate. The counterbored holes (and the tool hole) will remain positioned the same distance from the edges of the plate. If you change the height of the plate, the counterbored holes and the tooling hole will adjust to the new height of the thru face. The width dimension of the cutout (pocket) is large enough to accommodate a reasonable change and will remain positioned on the "center" datum planes. If you change the horizontal or depth (Z length) dimensions of the cut out area, it will remain centered between the left and right edges and the upper and lower faces of the plate (block). If you change the dimensions of the pivot boss (including the hole size), the hole that goes through it will remain centered between its faces. If you change the dimension of the chamfer on the pivot boss (pad), the blends will remain the same on all the edges of this feature. Change the depth of the cutout in the front of the part.

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Creating a Cover In this activity, you will create the following cover plate.

This is a plastic cover that will be made from a mold. To complete this project quickly, you should be familiar with the following features. (Review these lessons if you are unfamiliar with these features.) Cylinder Datum Plane Extruded Body Edge Blend Taper -

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Hollow Instance Feature Slot Boss Hole Pad -

Creating a Cover Methods Used in this Project You will create this cover plate.

In this project you will complete the following. Begin with a cylinder feature.

Create some intersection curves of the profile of the cylinder.

Extrude the intersection curves to create the right end of the part.

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Round off the right end corners.

Add a draft angle to the sides of the part.

Round off the bottom of the part.

Create the walls of the part.

Add a groove in the right face of the part.

Add another slot in the right wall.

Create some support material with a hole though it and the bottom of the part for a mounting screw.

Duplicate the mounting screw material and the slot on the front side of the part.

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Add a lip around the curved side of the part.

Add some more support material in the bottom of the part, then add a hole through it.

And finish with some blends.

Creating a Cover Dimensions of the Part These are the overall dimensions of this part (in millimeters).

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Creating a Cover Design Intent For this part you need to be able to vary these dimensions: The overall length and height of this part. The radius of its left end. The rounded corners of its right end. The size of the mounting holes and the material surrounding them. The size and placement of the cutouts in the right wall of the part. The size and placement of the central hole and the material surrounding it. You also want to keep the two mounting holes and the central hole centered within the part. You want to keep the two horizontal cutouts equidistant from the centerline of the part.

Creating a Cover Starting a New Part File (Metric) Open the part file standard_mm.prt from the fmf2 subdirectory, or start a new part file in millimeters. Use a part file name such as cover_1. The standard part file uses the following layer standards: Solid geometry on layers 1 through 20. Sketch geometry on layers 21 to 40 Curve geometry on layers 41 to 60 Reference geometry on layers 61 to 80 Sheet bodies on layers 81 to 100 Drafting objects on layers 101 to 120 Start the Modeling application.

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Creating a Cover Planning the Modeling of This Part You can see the basic shape of this part either as a cylinder and a block or as a block with one end rounded.

For this project you can begin with a cylinder feature, then extrude a profile of the cylinder to create the rectangular portion of this part.

Creating a Cover Creating the Basic Shape of the Part You can begin with a cylinder feature which will model the left side of the part.

Create a cylinder feature at this location. Choose the Cylinder icon or Insert Form Feature Use the Diameter, Height method. For the direction of the cylinder, use the ZC axis. For the origin, use the 0, 0, 0 location of the WCS. Key in the parameters for the cylinder (60, 8).

Cylinder.

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Creating a Cover Preparing to Create the Rectangular End of the Cover In order to model the rectangular right end of this part, you have planned to extrude a profile of a section of the cylinder. To do this you will need some datum geometry. You would like to have this datum geometry on its own layer. Make layer 61 the work layer. Create a datum plane through the axis of the cylinder. Choose the Datum Plane icon or Insert Form Feature Plane. Select the cylindrical face of the cylinder feature. Choose OK.

Datum

Create second datum plane through the axis of the cylinder but perpendicular to the first. Select the axis of the cylindrical face. Choose the Datum Plane Dialog. Choose the constraint of Angle. Select the datum plane in the view. Be sure the angle value is 90, and OK the dialog.

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Creating a Cover Creating Curves to Define the Cross Section of the Cylinder One way to create the curves you want is to have the system create curves at the intersection between the cylinder and the datum plane that cuts through the cylinder in along the YC axis of the WCS.

You would like to have these curves on their own layer. Make layer 41 the work layer. Use the "YC" datum plane to create intersection curves. Be sure these curves will be associated with the part. Choose the Intersection Curve icon or Insert Curve Operation Intersect. Be sure the First Set selection step icon is highlighted. Be sure the Associative Output option is on. Set Filter to Solid Body, and select the cylinder. Select the Second Set selection step icon (or just OK the dialog). Select the "YC" datum plane. OK the dialog.

Creating a Cover Extruding the Intersection Curves Now you are ready to create the rectangular right end of this part.

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Extrude the intersection curves. Choose the Extruded Body icon or Insert Form Feature Select the intersection curves. Use the Direction, Distance method. Be sure the direction arrow points to the right (along the XC axis). Key in the parameters for the extrusion (0, 50, 0, 0, 0). Unite the extrusion with the cylinder feature.

Extrude.

Creating a Cover Rounding Off the Corners of the Rectangular End You want the corners at the right of this part to be rounded.

First, you can make the intersection curves invisible. Make layer 1 the work layer again. Make layer 41 invisible but keep the datum planes on layer 61 selectable. Round off the two corners with a blend.

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Choose the Edge Blend icon or Insert Feature Operation Blend. Key in the radius value (10) for the blend. Select each vertical edge at the right end of the part. OK the dialog.

Edge

Creating a Cover Tapering the Side of the Part The sides of this part must have a slight draft angle.

Taper the vertical faces of this part from its top toward its bottom. Choose the Taper icon or Insert Feature Operation Be sure the taper Type is set to Faces. Be sure the Faces To Taper selection step icon is highlighted. Be sure the Collector is set to Faces. Select all six faces around the sides of this part. Choose the Draw Direction selection step icon. Leave the vector method set to Infer. If you need to, reverse the vector direction to point it downward. Choose the Reference Point icon. Leave the vector method set to Infer. Select the end point at the top end of any vertical edge. Key in the angle of the taper (3). OK the dialog.

Taper.

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Creating a Cover Rounding the Bottom of the Part You know that you are going to create the walls of this part by using a hollow feature. You also know that the bottom edge must be rounded. If you round this edge before you hollow out the part, you will maintain the desired wall thickness at the bottom of the part.

Blend the bottom edge of this part. Choose the Edge Blend icon or Insert Blend. Be sure the blend type is set to Edge. Turn the Add Tangent edges option on. Select any bottom edge. Key in the radius value for this blend (2). OK the dialog.

Feature Operation

Edge

Creating a Cover Creating the Walls of the Part Now you are ready to hollow out this solid to create the walls of the cover.

Hollow the solid to create the walls of this cover. Choose the Hollow icon or Insert Be sure the Type is set to Face.

Feature Operation

Hollow.

1314 Be sure the Pierced Face selection step is highlighted. Leave the filter set to Face. Key in the default thickness (1.0). Select the top face of the part as a pierced face. Choose Apply, then cancel the dialog.

Creating a Cover Creating a Cutout in the Right End of the Part Your next task is to create the small cutout in the top part of the wall at the right end of this part.

One way to do this is to use a rectangular slot that is positioned on the top edge of the right wall so that only half of it actually creates the cutout.

You can make the depth of this slot perpendicular to the tapered wall. Create the small cutout at the top of the right wall. Use a depth value that you know will completely penetrate the wall thickness. Run its horizontal up and down. Choose the Slot icon or Insert Form Feature Be sure the Thru Slot option is off. Choose the Rectangular option. Select the outside right face. For the horizontal reference, use the "XC" datum plane. Key in the parameters of the slot (4, 1, 7).

Slot.

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Position this slot at this location (but don't overconstrain it). Choose the Line onto Line icon. Select the top edge of the wall the slot is on. Select the horizontal centerline of the slot tool. Choose the Point onto Line icon. Select the "XC" datum plane. Select the vertical centerline of the slot tool.

If your design intent was that the sides of this slot had to be perpendicular to the XC-ZC plane (that is, drilled horizontally into the wall), you would first need to create a datum plane through the outside top edge of this wall, then create the slot on it.

Creating a Cover Creating the Small Slot in the Right Face of the Part There are two slots required in the right face of this part along with two bosses for the mounting screws.

Your plan is to create one slot and one boss on one side of the part, then instance both of them to the other side.

1316 Create a slot in the right wall of this part toward the back. Be sure to use a depth that you know will completely penetrate the wall thickness. Keep the length of the slot horizontal to the top edge of this right wall. Choose the Slot icon the Insert Form Feature Slot. Be sure that the Thru Slot option is off. Choose Rectangular. Select the right outside face of the part. For the horizontal reference, select the top edge of the face the slot will be placed on. Key in the parameters of the slot (2, 1, 6).

Use the top edge of the wall and the "XC" datum plane to position the slot. Choose the Parallel At a Distance icon. Select the top outside edge of the wall. Select the horizontal centerline of the slot tool. Key in the distance (3). Choose the Perpendicular icon. Select the "XC" datum plane. Select the vertical centerline of the slot tool. Key in the distance (14).

Creating a Cover Planning the Modeling Method for the Mounting Screw Material This cover is held in place with two mounting screws. Your next task is to create the material that will support them.

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You will notice that extra material is required near the floor of this part.

One way to do this is to use two bosses (with a counterbored hole through them). You can create just one, then mirror it (along with the slot) to the other side of the part.

Creating a Cover Creating the First Boss Create a boss on the inside face at the bottom of the part. Choose the Boss icon the Insert Form Feature Key in the parameters for this boss (6, 2, 3).

Boss.

Select the top face at the bottom of this part. Use the two datum planes to position it at this location. Choose the Perpendicular icon. Select one of the datum planes, then key in the distance from it. Repeat this procedure with the other datum plane.

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Creating a Cover Creating a Second Boss on the First You can finish the support material needed by adding a second boss on top of the first.

Create another boss, this time centered on the top of the first boss. Choose the Boss icon or Insert Form Feature Key in the parameters for this boss (4, 2, 3).

Select the top face of the existing boss. Center this boss on the top face of the first boss. Use the Point onto Point method.

Boss.

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Creating a Cover Creating the Counterbored Hole

Create a counterbored hole on the bottom face of the part. Make it go completely through both bosses. Choose the Hole icon

or Insert

Form Feature

Hole.

Choose the Counterbore option. Key in the parameters of the counterbored hole (4, 2, 2).

For the placement face, select the bottom face of the part. For the thru face, select the top face of the upper boss. Position this counterbored hole along the axis of the boss. Use the Point onto Point method.

Creating a Cover Duplicating the Countersunk Hole and the Rectangular Slot Now that you have the countersunk hole material and the rectangular slot, you can duplicate them on the front side of the part by mirroring them.

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Use the "XC" datum plane to mirror both the countersunk hole material and the rectangular slot feature. Choose the Instance Feature icon or Insert Feature Operation Instance. On the Instance dialog, choose the Mirror Feature option. On the Mirror Feature dialog, be sure the Feature to Mirror selection step icon is highlighted. In the Features In Part list box, choose the four features you want to mirror (use Control+Select), then use the right arrow option to move them into the Features In Mirror list box. Choose the Mirror Plane selection step icon. Select the "XC" datum plane as the mirror plane. OK the dialog.

Creating a Cover Adding Support Material Around the Curved Upper Edge of the Part This part needs some extra material around the top of its round (left) end.

One way to create this material is to create an extrusion using the inside edge of the part. Extrude the top inside edge to create this cross section around the top of the curved side of the part. Be sure the direction of the extrusion will be downward, and offset the extrusion into the part. Choose the Extruded Body icon

or Insert

Form Feature

Extrude.

1321 Select the inner top edge. OK the dialog. Use the Direction, Distance method. Point the direction arrow downward. Key in the parameters of the extrusion (including its offset value) (0, 1, 0, 1, 0). Unite the extrusion with the solid.

Creating a Cover Adding Material for a Hole in the Bottom of the Part You need to add a rectangular pad of material on the floor of this part. Eventually it will have a hole drilled through it. It will need to be positioned along the center of the part (along the XC axis) and at a certain distance from the bottom of the right wall.

Add a rectangular pad to the inside face at the bottom of the part. You will want the horizontal reference of this feature to run from back to front. Choose the Pad icon or Insert Form Feature Pad. Use the Rectangular method. Select the inside face at the bottom of the part. For the horizontal reference, select the "YC" datum plane. Key in the parameters of the pad (20, 15, 2, 2, 3). OK the dialog.

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Position this pad in the left-to-right center of the part. Use the inside lower edge at the right side of the part to define the distance to the center of the pad. Choose the Line onto Line icon. Select the "XC" datum plane. Select the vertical centerline of the pad tool. Choose the Perpendicular icon. Select the inside bottom smooth edge (of the blend). Select the horizontal centerline of the pad tool. Key in the distance value (25). OK the dialog.

Creating a Cover Preparing to Center a Hole in the Pad You will want to keep the hole that will go through this pad centered in the pad. One way to do this is to create datum geometry that will allow you satisfy the design intent.

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You would like to have this datum geometry on its own layer. Make layer 62 the work layer. Create a datum plane through a topmost left edge of the pad parallel to the YC datum plane. HINT: Avoid selecting control points. Choose the Datum Plane icon or Insert Form Feature Datum Plane. Select top left edge of the pad at a place where there are no control points. Select the YC datum plane. Key in an angle of zero. Choose OK.

Create a second datum plane through a topmost right edge of the pad, again parallel to the YC datum plane. Use the same procedure you used for the first datum plane.

Finally, create a third datum plane that is centered between the two new datum planes. Select each of the new datum planes.

1324 Choose OK.

Creating a Cover Creating a Hole Through the Pad When you create this hole, you can position it with the "XC" datum plane and the datum plane that is centered in the pad and is perpendicular to it.

Create a simple hole that goes completely through the bottom of the part and the pad. Choose the Hole icon

or Insert

Choose the Simple Hole option. Key in the parameter of the hole (4).

Form Feature

Hole.

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For the placement face, select the bottom face of the part. For the thru face, select the top face of the pad. Use the datum planes to keep this hole centered within the pad. Choose the Point onto Line icon. Select the "XC" datum plane. Choose the Point onto Line icon again. Select the datum plane centered between the two "pad edge" datum planes.

Creating a Cover Blending the Bottom Edges of the Pad and the Bosses The base of the pad needs to be blended into the floor of this part. Even though the pad height is 1 mm, you can use a larger radius blend. Make layer 1 the work layer, then make layers 61 and 62 invisible. Add a 2 mm blend all around the lower edge of the pad. Choose the Edge Blend icon

or Insert

Feature Operation

Edge

1326 Blend. Be sure the Add Tangent Edges option is on. Key in the radius value (2). Select any bottom edge on the pad. OK the dialog.

Add a 1 mm blend around the bottom of each boss.

Creating a Cover Modifying the Part There are many dimensions you can modify on this part without "breaking" it. Of course there is a limit to the amount of variation you can introduce. You can vary these dimensions: The overall length and height of this part. The radius of its left end. The rounded corners of its right end. The size of the mounting holes and the material surrounding them. The size and placement of the cutouts in the right wall of the part. The size and placement of the central hole and the material surrounding it. You also want to keep the two mounting holes and the central hole centered within the part. You want to keep the two horizontal cutouts equidistant from the centerline of the part.

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-Free Form ModelingOverview of Free Form Modeling In this course, you will learn how to create and edit free form features, some of which are shown here.

Free form features can be sheets or solids that have one or more B-Surfaces or trimmed planar surfaces. Because of their construction techniques and design applications, these surfaces are usually stylistic.

Using Free Form Features In this activity, you will perform the following tasks. Set up toolbars for creating and editing features. Set up Modeling Preferences for free form features. Learn about creation techniques based on available geometry. The Free Form Modeling course shows you how to create more "stylized" features that have soft, curved faces. Most of these free form features will be sheet bodies.

Using Free Form Features Opening the Part

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Open part file fff_fff_1.prt from the fff subdirectory. A free form sheet body displays. Start the Modeling application. This Ruled feature was created with two curves: one at the top of the sheet and one at the bottom.

For this course, you may want to display and dock several toolbars for easier selection of creation and editing icons.

Using Free Form Features Setting up Toolbars for this Course You should display the following toolbars: Free Form Feature, Edit Free Form Feature, Form Feature, Feature Operation, and Edit Feature. If these toolbars are not displayed, choose View

Toolbars

Customize.

The Customize dialog displays. On the Customize dialog, choose the Toolbars tab, and turn on the toolbars you want to display: Free Form Feature, Feature Operation, Form Feature, Edit Feature, and Edit Free Form Feature. To specify the icons for toolbars, choose the Commands tab, select each toolbar name from the Toolbars list, and turn on all of the icons for each toolbar. Close the dialog.

1329 The toolbars for Free Form Feature, Edit Free Form Feature, Form Feature, Feature Operation, and Edit Feature should display, so you should position them for your convenience. The following link will show you the types of Free Form Feature creation icons that you'll use in this course.

Free Form Feature Creation Icons Used in this Course

This course covers these free form feature types found on the Free Form Feature toolbar. Through Points From Poles From Point Cloud Ruled Through Curves Through Curve Mesh Swept N-Sided Surface Section Body Extension Law Extension Enlarge Offset Surface Bridge Global Shaping Trimmed Sheet Quilt Fillet Surface This course also covers these Form Features. Bounded Plane

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Thicken Sheet This course also covers these Feature Operations. Face Blend Soft Blend

The following link will show you the types of Free Form Feature editing icons that you'll use in this course.

Feature Edit Icons Used in this Course

This course covers only one Edit

Feature option.

Edit Feature Parameters This course covers these Edit

Free Form Feature options.

Move Defining Point Move Pole Isoparametric Trim/Divide Sheet Boundary Change Degree Change Stiffness Change Edge Reverse Normal

Using Free Form Features Setting General Modeling Preferences You can use Preferences Modeling to set preferences such as distance and angle tolerances, density, density units, and surface grids. Choose Preferences

Modeling.

1331 Choose the General tab. The Modeling Preferences General tab displays the following options.

For complete information on all options, refer to the Unigraphics NX online help.

Using Free Form Features Specifying the Body Type The Body Type option is used with the free form feature options for Through Curve Mesh, Through Curves, Swept, Section, and Ruled.

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For now, leave the Body Type set to Solid.

Using Free Form Features Tolerances Distance Tolerance is a multipurpose tolerance used by many Modeling functions; and often the maximum allowable distance between the true theoretical sheet and the resulting approximated sheet that the system creates. Feature creation methods that use approximation require a distance tolerance. Angle Tolerance is the maximum allowable angle between the normal of the true theoretical sheet and the normal of the sheet that the system creates to approximate it. Some methods require an angle tolerance. Even when the distance tolerance has been met, it is possible that more segments would have to be added to meet the angle tolerance. If you find that the sheet created has an excessive amount of data or that sheet creation is taking too long, you may want to increase the angle tolerance or possibly make the angle tolerance very large to, in effect, remove that tolerance from consideration.

Using Free Form Features Grid Lines Grid lines are a display feature that can help you visualize the shape of a free form surface.

1333 The Grid Line U Count and V Count values are the number of grid curves in the U and V directions of the model that you are creating. To change the values, simply key in the values you desire for the U Count and V Count, and choose OK on the Modeling Preferences dialog. If the grid counts are small, the surface may appear to be jagged. To obtain a smoother display, you may want to use a larger number of grid curves. Grid Lines do not effect the accuracy of the actual surface.

Using Free Form Features Setting Free Form Modeling Preferences Choose the Free Form tab on the Modeling Preferences dialog. The dialog displays options that are useful for construction of free form features.

Using Free Form Features Free Form Construction Result The Free Form Construction Result controls whether a plane or B-Surface is created for these free form features: Through Curves, Through Curve Mesh, Swept, and Ruled. When the Plane option is toggled on, and the creation geometry would produce a planar surface, a bounded plane is created. Using the B-Surface option tells the system to always create a B-Surface.

1334 Using bounded planes instead of B-Surfaces enhances the performance and reliability of downstream applications. However, if the isoparametric curves or flowlines of the surface are important to your application, the B-Surface option gives you control over this data.

Using Free Form Features Curve Fit Method The Curve Fit Method controls the fitting method used when curves must be approximated by splines. If the result can be exactly replicated by a spline of any degree, that spline will be created. Cubic uses degree 3 splines. If you need to transfer your spline data to another system that only supports degree 3 splines, you should use this option. Quintic uses degree 5 splines. A spline created with the Quintic option will better replicate the curvature properties of the true curve. Cancel the Modeling Preferences dialog.

Geometry Used for Free Form Features

The following types of geometry can be used to create free form features. Creating features from points.

Features from Point Geometry

If construction geometry includes only points, you may be able to use one of these three options to build the feature. From Point Cloud - if you have scattered points. Through Points - if defined points form a rectangular array. From Poles - if defined points form a rectangular array.

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Creating features from section strings.

Features from Section Strings

If construction geometry contains strings of connected objects (curves, faces, and edges), you may be able to use one of these two options to build the feature. Ruled - if the two strings are roughly parallel.

Through Curves - if the three or more strings are roughly parallel.

If construction geometry contains one or more strings (curves, faces, edges) that are roughly parallel to each other, and one or more section strings that are roughly perpendicular the first set of curves, you may be able to use one of these options to build the feature. Swept - if at least two strings are positioned in a roughly perpendicular orientation.

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Through Curve Mesh - if at least four strings exist with at least two strings in each direction. Bounded Plane - if coplanar strings form a closed loop.

Creating features from faces.

Features from Faces

If the construction geometry contains a sheet or face, you may be able to use one of these options to build the feature. Offset Surface - if you have faces to offset.

Thicken Sheet - if you have a sheet body. Enlarge - if you have a face. Extension - if you have a face and edges, edge curves, or curves on the face.

1337 Law Extension - if you have faces, edges, and edge curves.

Creating features from faces, tangency strings, limits, and more.

Features from Other Geometry

If the construction geometry contains faces, and optional spline strings, limiting points, and faces to which tangency needs to be maintained, and other geometry, you may be able to use one of these options to build the feature. Fillet Surface - if you have faces, tangency strings, and limits. Face Blend - if you have faces and tangency strings.

Soft Blend - if you have faces, tangency strings, and a spline. Bridge - if you have faces, and edges.

Section Body - if you have specialized free form construction options.

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Trimmed Sheet - if you have one sheet and trim objects. Quilt - if you have multiple faces, a driver sheet, or two sets of curves that form a rectangularly shaped closed loop.

Geometry Used for Free Form Features Applications for Sheet Bodies There are many ways to use sheet bodies. Some of the ways are listed here. You can create contours and shapes that would be difficult to achieve with standard solid modeling. You can trim a solid body to create a contour or shape on one or more faces of the solid body. You can create a solid body by sewing several sheets together to totally enclose a volume. You can surface a wire frame part.

For more information on concurrent engineering and design tips, use these links.

About Concurrent Engineering

The ideal situation in preparing models for manufacturing involves a concept known as concurrent engineering.

1339 This means that the designer and N/C programmer communicate throughout the design process. Communication must occur early in the conceptual design stage of the project so that the programmer can offer suggestions to help the designer avoid modeling problems and gain insight into the proper manufacturing approach for the model.

Design Tips for Features

It is critical that you use accurate construction geometry to create free form features. If your construction geometry is irregular, the final free form features may contain undesireable surface undulations, and may be difficult or impossible to machine. Remember to make the model full scale, because manufacturing will cut the actual part. Keep the model as simple as possible. Use different layers and category names to organize the information in the part file. Use the largest radius possible. The smaller the radius, the smaller the tool required to machine the part. This will increase the complexity of the manufacturing process. Use an internal corner radius slightly larger than standard tooling available so that circular cutting can be done to avoid abrupt directional changes which cause wall marks. Sometimes filleting is not required. For example, you could let the tool corner radius create the fillets on the part. Because many design-based manufacturing problems are caused by improperly trimmed curves, look for improperly trimmed objects, and correct for sharp transitions or kinks where sheets meet.

Manufacturing Free Form Features

Manufacturing modules are face normal based. They do not recognize types of faces. Ruled free form features sheets will have different face normal vectors than curve mesh sheets, and the CAM processors will determine tool positions depending upon the module used. You should keep in mind this requirement of tool positioning to face normals of free form features as you design a model. Use the simplest free form features possible when you are designing a model. Complex free form features will take longer to machine.

Close all part files.

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Through Points This lesson covers creating free form features through points.

The Through Points option is useful when you are creating features using rows of points.

Creating a Multiple Patch Through Points Feature by Chaining Points In this activity, you will learn to perform the following tasks. Create a multiple patch sheet body with points. Select points using the Chain from All option. Analyze the face and check for surface undulations.

You will create a free form sheet body through seven rows of points, using Through Points.

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Creating a Multiple Patch Through Points Feature by Chaining Points Opening the Part Open part file fff_thrupoints_1.prt from the fff subdirectory. Start the Modeling application. The part file contains seven rows of point data.

The Grid Lines in Modeling Preferences have been set to 10 for both the U and V directions.

Creating a Multiple Patch Through Points Feature by Chaining Points Starting the Through Points Feature

The Through Points icon lets you create a body (sheet or solid) that passes through a defined rectangular array of points.

Choose the Through Points icon Through Points.

or choose Insert

Free Form Feature

A Through Points dialog displays. Before you can select the points, you must specify the patch type.

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The Points From File option lets you import points from an ASCII text file. These points could have been created from computer generated data, machine generated data, manually entered data, etc. When Points From File is chosen, a Point File dialog displays that lets you choose the *.dat file to be imported. You will not use this option now. Single patch type creates a body with one patch. You can use a single patch if you have from 2 to 25 points in the row and in the column.

Choose the Single Patch Type option. Notice that the other options are grayed out, because the system automatically determines the row and column degree for single patch bodies. The system determines the degree for the row and column as follows: The row degree (U direction) is one less than the number of points in the row with the highest number of points. The number of points per row can range from 2 to 25. The column degree (V direction) is one less than the number of rows. In the example below, the column degree = 3, and the row degree = 5.

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Creating a Multiple Patch Through Points Feature by Chaining Points Using the Multiple Patch Option Multiple patch type creates a body with a rectangular array of patches. With multiple patch bodies, you must specify a method of closure, the row degrees, and column degrees.

You need to use the Multiple patch option, because there are too many points in this part file for you to use a single patch option. Choose the Multiple patch type. Closed Along options let you specify how you want the body closed.

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The Closed Along Rows option lets you create a body where the first column of points become the last, as shown below.

The Closed Along Columns option lets you create a body where the first row of points becomes the last, as shown below.

The Closed Along Both option lets you close the body in both directions (rows and columns), as shown below.

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If you close the body in both directions, or you close the body in one direction and in the other direction the ends are planar, the system creates a solid body when the Modeling Preferences are set to "Solid". The closed along Neither option creates a sheet that begins and ends with the specified points. The body will not be closed.

Use the Closed Along option of Neither. The row degree can be a value from 1 to 24. The column degree can be a value from 1 to 24. Use 3 for both the Row Degree and Column Degree. Choose OK in the dialog.

Creating a Multiple Patch Through Points Feature by Chaining Points Selecting Points in the First Row A next dialog displays four selection options: Chain from All, Chain within Rectangle, Chain within Polygon, and Point Constructor. With Chain from All, you select the first and last point in each row. This works well if the points in each row are close together. With Chain within Rectangle, you drag a rectangular box around the points in the row. With Chain within Polygon, you indicate a series of locations, creating a polygon around the points in the row. You can use Point Constructor if you want to select the points in very specific ways.

1346 Since the points in each row are close together, Chain from All makes selection easy. Choose Chain From All. A dialog displays that lets you select points by name, but you will select directly from the view. Select the start point of the left row. The selected point highlights in the system color. Select the end point of left row.

The first row of points highlights.

1347

Creating a Multiple Patch Through Points Feature by Chaining Points Selecting Additional Rows of Points You need to select the next row of points. Select the start point of the row immediately next to the row that you just finished selecting. Select the end point of that same row. Again, the entire row highlights. Select the start point and end point of each of the next two rows. Four rows are now highlighted.

The dialog lets you stop selecting rows of points (All Points Specified), or specify an additional row (Specify Another Row). These options display, because you specified a column degree of three, and you selected four rows of points (the minimum number of rows required to create a body with the column degree of three). You will continue to select rows. Choose Specify Another Row. Select the start and end point for the next row. For each of the remaining rows, choose Specify Another Row, and select the start and end points of the row.

1348 All rows should be highlighted now. Choose All Points Specified to tell the system that you have finished selecting rows of points. The sheet body is created. Cancel the Through Points dialog.

Creating a Multiple Patch Through Points Feature by Chaining Points Changing Your Display The U, V grid displays on the sheet, based on the U, V grid values saved with this part file. Refresh your view.

To eliminate the display of points, you need to make layer 100 invisible. Make layer 100 invisible so that the points do not display. The grid gives you an idea of how smooth the sheet body is.

Creating a Multiple Patch Through Points Feature by Chaining Points Shading the Sheet Body Shade the model.

1349 You should always check free form bodies for irregularities. Shading the model will make surface undulations more visible.

One hazards in using too many points for a sheet or solid body is that surface irregularities may develop. You can reduce or eliminate irregularities by using the Points From File to import other points that represent a smoother surface; or by moving or deleting some of the existing points; or by obtaining better point data. Return to a Wireframe display.

Creating a Multiple Patch Through Points Feature by Chaining Points Finding Information on the B-Surface When you are creating parts for machining, it is important to check the face smoothness. The system will let you know whether the face is mathematically smooth and aesthetically pleasing. The Information option lets you check the B-Surface. Remember, you can refer to the Unigraphics NX online help for details about all of these options. Choose Information

B-Surface to display the analysis dialog.

The B-Surface Analysis dialog lists information options.

1350

Show Patch Boundaries - displays all patch boundaries of the selected B-Surface Show Poles - displays all poles of the selected B-Surface Output to Listing Window - Information window displays numbers of poles and seams, continuity types, number of patches in U and V, degree of the B-Surface, and rational or polynomial status. To see the information in a printable format, you need to output the data to an information window. Toggle Output to Listing Window to on. Choose OK. Another dialog displays to let you select the B-Surface by name. Select the sheet body and choose OK. The Information window displays the number of poles in the U and V directions, the number of C0, C1, and C2 continuous seams, and the number of patches in the U and V directions of the untrimmed B-Surface.

Close the Information window. The patch boundaries display in the object color (red for this part), with different fonts to indicate multiple levels of continuity: C2 in solid font, C1 in dashed, and C0 in dotted. The control polygon is displayed in the system color.

1351

Do not use Refresh, Update Display, or Fit options, while the temporary display of the patches and seams is present, because the options will remove the display of the patch boundaries, levels of continuity, and control polygons. Use the Zoom, Zoom In/Out, Pan, Rotate, and Restore options to look at the details of the patch boundaries and continuous seams. This is one way to check this B-Surface. Refresh the view.

Creating a Multiple Patch Through Points Feature by Chaining Points Analyzing the Faces The Analysis display.

Face

Radius option lets you choose one or more faces for the color analysis

Face analysis displays can be created for a number of analysis types, including shaded, color-coded plots, color-coded spines on face grid points, and face reflections. Face analysis displays are useful for detecting inflections, variations, and defects on faces. Reflection options are useful for visualizing objects and evaluating their aesthetic quality. The Analysis Face, and Analysis Curve options let you detect irregularities such as inflections, flat sections, and sharp corners on faces or curves.

Choose the Face Analysis - Radius icon from the Analyze Shape toolbar, or choose Analysis Face Radius to display the Face Analysis - Radius dialog.

1352 The Face Analysis - Radius dialog displays.

Options that are not available at this time will be grayed out on the dialog. If you need to analyze more than one face, you can select and confirm each face, but you only need to analyze one face in this part file. You need to select the sheet that you want analyzed. Select the sheet.

Creating a Multiple Patch Through Points Feature by Chaining Points Analysis Options Various Radius Types are available.

1353

Various Radius Types

The Mean, Minimum, or Maximum radius displays color-coded output to analyze the radius of curvature at each point on the face. For quantitative analysis, you should use the Minimum Radius option, because these results can be used to decide the maximum tool radius that can be used for machining purposes. The Normal radius is used with the Reference Vector option. At each point, the curvature is evaluated by cutting the face with a plane that contains a normal to the surface and a specified reference vector. This is useful for fluid dynamics analysis. You would define the Reference Vector that is parallel to the flow direction. The Sectional radius method is used with the Reference Plane option. At each point, the curvature is evaluated by cutting the face with a plane that passes through the point and is parallel to the specified reference plane. U radius is the radius in the U direction. V Radius is the radius in the V direction. These options are available with the Fringe, Hedgehog and Contour Lines Analysis types. The Gaussian radius option displays a color-coded output according to the Gaussian radius of curvature for the face at that point. This option may be useful for identifying saddle-shaped regions on the surface. You'll use this option. On terminals that support hardware shading, the Reflection Lines and Contour Lines display options will be available.

The Gaussian radius option displays a color-coded output according to the Gaussian radius of curvature for the face at that point. This option may be useful for identifying saddle-shaped regions on the surface. You'll use this option. Use the Gaussian radius analysis type and choose Apply. The display provides you with a qualitative check on the shape of the surface. On terminals using a 3D driver, the display colors are continuous. If two curvatures are nearly the same, the two color hues displayed will also be nearly the same, like this.

1354

On terminals using a 2D driver, the range of colors is comparatively limited. In the graphics area, press MB3 and choose Display Mode display to a wireframe display.

Wireframe to return the

Close all part files.

Creating a Multiple Patch Through Points Feature by Selecting Each Point In this activity you will learn to perform the following tasks. Create a sheet body using the Point Constructor to select points. Analyze the B-Surface that you create. You will create a sheet body with the nine rows of points like this.

1355

Creating a Multiple Patch Through Points Feature by Selecting Each Point Opening the Part Open part file fff_thrupoints_2.prt from the fff subdirectory, and start the Modeling application. The dashed lines between the points were created to make the rows more obvious.

1356

Creating a Multiple Patch Through Points Feature by Selecting Each Point Starting the Through Points Feature Choose the Through Points icon Through Points.

or choose Insert

Free Form Feature

The Through Points dialog displays the Through Points defaults: Multiple patch, Closed Along Neither, Row Degree 3, and Column Degree 3.

Choose OK to accept the defaults on the Through Points dialog (multiple patch, degree of three).

Creating a Multiple Patch Through Points Feature by Selecting Each Point Selecting Points in the First Row You cannot use the Chain From All option, because the points are not closely spaced in each row. You need to individually select the points. Choose Point Constructor. The Point Constructor dialog displays. Choose the Existing Point icon. About Selecting Points

When selecting points (or poles), you need to select them in approximately the same order for each row.

1357

If you select points in differing orders, you may get self intersecting, or convoluted shapes.

Carefully select the five points in the top row, and OK the dialog.

Since you are done specifying points, you can indicate this in the next dialog. Choose Yes to specify that all points have been selected for the first row.

Creating a Multiple Patch Through Points Feature by Selecting Each Point Selecting Points in the Next Three Rows The Point Constructor dialog displays again, so you can select another row. Choose the Existing Point icon

, select the second row of points, choose OK, and Yes.

1358 (Remember, start your selection at the same side so that the part does not twist.) Repeat this process to select the third, and fourth rows of points. (Remember, start your selection at the same side so that the part does not twist.)

Four rows have been selected, which is enough to satisfy a degree of three.

Creating a Multiple Patch Through Points Feature by Selecting Each Point Completing the Selections You need to select more rows. Choose Specify Another Row. Choose Existing Point , repeat the process of selecting the points in the next row, choose OK, Yes, and Specify Another Row. Repeat this process until all rows of points have been selected. When you have selected the last row of points, choose All Points Specified. The sheet body is created. Notice the undulations in the sheet body.

1359

Cancel the Through Points dialog.

Creating a Multiple Patch Through Points Feature by Selecting Each Point Analyzing the B-Surface Make layer 1 invisible and Refresh the view. As you model free form features, you should evaluate the surfaces. Choose Information

B-Surface.

The B-Surface Analysis dialog displays. Toggle off the Output to Listing Window, if needed. Choose OK. The B-Surface Analysis name dialog displays. You need to select the B-Surface. Select the sheet body. Choose OK to analyze the sheet. Depending on your design intent, you may not want so many undulations.

1360

Refresh the view. Remember, you can also analyze the face of the sheet body as you did in an earlier activity. Close all part files.

1361

From Poles This lesson covers creating free form features From Poles. You can use the From Poles option to specify points as poles (vertices) of a control net that defines the shape of a body. From Poles gives you better control of the overall shape and character of the body than does Through Points. The use of poles also minimizes unwanted undulations in the face of the free form feature.

Creating a Multiple Patch Sheet Body Using From Poles In this activity, you will learn how to perform the following tasks. Create a sheet body using From Poles. Analyze the surface of the sheet. You will use From Poles to create this sheet body.

1362

Creating a Multiple Patch Sheet Body Using From Poles Opening the Part and Starting the Feature Open part file fff_from_poles.prt from the fff subdirectory, and start the Modeling application. The dashed lines between points are for your reference.

Choose the From Poles icon

or Insert

Free Form Feature

From Poles.

The From Poles dialog displays. It has the same options as the Through Points dialog.

At the bottom of the dialog, the Points from File lets you import points.

1363

Creating a Multiple Patch Sheet Body Using From Poles Selecting the First Row of Points Since the points already exist in this file, you will select them. For this activity, you can just use the defaults on the From Poles dialog. Choose OK to accept the defaults on the dialog. The Point Constructor dialog displays. Unlike the Through Points option, where you had four methods to select points, the From Poles selection must be completed by using the Point Constructor dialog. You will be selecting only existing points. Choose the Existing Point icon. Select the five existing points in the top row. (Remember to zoom in on the points for easier selection.)

Notice that when you use From Poles, rubber banding displays as you move from point to point. This did not happen when you selected the points using the Through Points option.

Choose OK. Since you have selected all the points in the first row, you need to confirm it.

1364 The Specify Points dialog displays Yes/No options. Choose Yes to confirm your selections.

Creating a Multiple Patch Sheet Body Using From Poles Selecting the Remaining Rows of Points You need to select the next row. Remember to select the points beginning at the same side of the part to prevent twisting of the final body. The Point Constructor dialog displays again. Choose the Existing Point icon. Select the five points in the second row. Choose OK on the Point Constructor dialog. The Specify Points dialog displays Yes/No options. Choose Yes to confirm that your point selection is complete. Creating a Multiple Patch Sheet Body Using From Poles Completing the Model

You need to continue selecting other rows. Using the same procedure, select the five points in the third row. Using the same procedure, select the five points in the fourth row. Choose Specify Another Row. The Point Constructor dialog displays again. Repeat the procedure to select the remaining rows of points. When you have selected the last row of points, choose All Points Specified. Refresh the view. The sheet is created.

1365

Cancel the From Poles dialog.

Creating a Multiple Patch Sheet Body Using From Poles Analyzing the Sheet Body Layer six contains a Through Points sheet body. Make layer 6 the Work Layer and 1 Invisible, and fit the view. Notice the differences between the surfaces. The From Poles sheet has a smoother surface than Through Points.

1366

You can also use the Face Analysis Radius option to check the surfaces. If you are using a 3D graphics driver, you may see shaded images like these.

Close all part files.

1367

From Point Cloud This lesson covers creating free form features from a cloud of points.

You can use the From Point Cloud option to create a body (sheet or solid) that passes through a specified rectangular array of points. This is a simple way to create a sheet body that approximates a large cloud of data points, typically produced by scanning or digitizing.

Creating a Sheet Body from a Cloud of Points In this activity, you will use the From Point Cloud option to create this sheet body by using a set of points.

Creating a Sheet Body from a Cloud of Points Opening the Part Open part file fff_cloud.prt from the fff subdirectory, and start the Modeling application.

1368

Creating a Sheet Body from a Cloud of Points Starting the Feature

Choose the From Point Cloud icon Cloud.

or Insert

Free Form Feature

From Point

The From Point Cloud dialog displays.

As with Through Points, and From Poles, you can import points using Points From File.

1369 The Confirm Upon Apply option lets you view and analyze the feature before you create it. Toggle off the Confirm Upon Apply option on the From Point Cloud dialog.

Creating a Sheet Body from a Cloud of Points Selecting the Points

The From Point Cloud function should be used on dense sets of points, like those from laser scanners. It may not work well for a small number of points. There is no limit to the number of points, other than system memory. However, memory limits may be exceeded if you have too many points. In these cases, you may want to select fewer points. There is no requirement on the organization of the points. They may or may not be organized in "scan lines." The distribution of the points on the proposed surface is very important - each patch on the proposed surface must have a sufficient number of points lying on it. You can avoid this problem by using small numbers of patches. Select the points by dragging a rectangle around all the points in the view. The system creates a coordinate system in the view of selection, because "View of Selection" is the current Coordinate System setting on the dialog.

The boundary that displays encloses all selected points, and the U and V direction vectors display. As you select/deselect points, the size of the boundary will change. The points should be evenly distributed over the rectangular area. Since they are not distributed equally within the boundary, you need to realign the temporary coordinate system.

1370

Creating a Sheet Body from a Cloud of Points Selecting the Coordinate System

The From Point Cloud dialog provides coordinate system selections. The chosen Coordinate System consists of a vector approximately normal to the sheet body, that corresponds to the Z axis. The U and V direction vectors correspond to the X and Y axes. View of Selection - The U-V plane is in the plane of the view, and the normal vector is normal to the view. The U vector points to the right, and the V vector points up. WCS - This uses the current Work Coordinate System. Current View - The coordinate system of the current work view. Specified CSYS - Selects the coordinate system previously defined by using Specify New CSYS. If a CSYS has not been defined, this will behave just like Specify New CSYS. Specify New CSYS - Brings up the CSYS Constructor dialog, which you can use to specify any coordinate system. You must specify a coordinate system so that the completed sheet body will not fold under itself when viewed along the Z axis. If a normal vector is specified that violates this requirement, the resulting sheet body will be dramatically different and probably not what you want. For this part, you need to align the temporary coordinate system with the WCS. Choose WCS as the Coordinate System. The U and V coordinates redisplay.

The boundary is now aligned so that points are more evenly distributed within the boundary.

1371

Creating a Sheet Body from a Cloud of Points Specifying U and V Degree and Patches You can independently specify the Degree and number of Patches in both directions. The default degree of 3 is recommended, but you could use a value from 1 to 24, if you have enough points. The combination of degree and patches in the two directions controls the distance error between the input points and the created body. Generally, you will need one patch each time the slope varies as much as 90 degrees in the corresponding direction. You can use fewer segments with higher degrees. Memory limits may be exceeded when the U and V degree or patch values are too high. Use the defaults, but do not OK the dialog yet. The number of points selected must be at least (Row Degree + #Row Patches) * (Column Degree + #Column Patches). If this is not true, you must select more points or reduce the value of some of the parameter values.

Creating a Sheet Body from a Cloud of Points Specifying the Boundary You need to specify the Boundary for the feature. The default boundary for the body is generated by projecting all selected data points onto the U-V plane. The Minimum Box that encloses all points is found and projected along the normal vector onto the cloud of points.

Boundary Conditions for a From Point Cloud Feature

Unconstrained areas within the boundaries can result in wild twists in the sheet body, as shown below. Areas that were unconstrained, because they did not contain any points, are erratic in the sheet body produced.

1372

In a case where a part is erratic, you may want to provide a Specified Boundary - a different quadrilateral (four-sided polygon) to be projected onto the point cloud. You do this by specifying four corner points, which are projected onto the U-V plane along the normal axis. The resulting quadrilateral must be convex. Note that specifying a new boundary does not change the U-V plane of the coordinate system. However, the U and V vectors will change direction within the plane. The direction of the U vector is determined by connecting the midpoint of the 1- 4 segment to the midpoint of 2 - 3. The direction of the V vector is determined by connecting the midpoint of 1 - 2 to the midpoint of 3 - 4 (The V vector is not necessarily perpendicular to the U vector). The origin is the intersection of these two lines.

Use the Minimum Box as the Boundary option. The Specify Boundary option lets you specify the corners for boundary.

1373

Creating a Sheet Body from a Cloud of Points Deviation Values Choose Apply on the From Point Cloud dialog. The feature is created. The Fit Information dialog displays the average and maximum deviation. Choose OK in the Fit Information dialog to close it.

The Average deviation and Maximum deviation are an analysis of the distance the sheet body differs from the original points in the direction of the normal to the U-V plane. The true 3D distance from the sheet body to the points is never greater than this number and it is usually less. These numbers are most useful for comparing the results from two different sets of input parameters. The display updates, showing the boundary, the U and V direction vectors, the coordinate system used, and the feature. Cancel all dialogs. You will see a data point (near the WCS), which is highlighted in the system color. This data point is the one with the maximum distance from its intended position on the sheet body.

Close the part file.

1374

Ruled This lesson covers creating Ruled features. A Ruled feature is created through two section strings.

Creating Ruled Sheet Bodies with Parameter Alignment In this activity, you will: change Modeling Preferences for the U and V grid count values, use both Plane and B-Surface Free Form Construction techniques, and use Information options to check the type of faces that you have created.

1375

Creating Ruled Sheet Bodies with Parameter Alignment Opening the Part Open part file fff_ruled_parameter_align.prt from the fff subdirectory, and start the Modeling application. Many curves display in the view.

Creating Ruled Sheet Bodies with Parameter Alignment Setting Modeling Preferences

In order to create a planar sheet body, and display the surface in wireframe, you need to set two Modeling Preferences. Choose Preferences

Modeling.

Choose the General tab. So that you can see the surface more easily, set the U Count and V Count Grid Lines to 10. Choose the Free Form tab. Make sure that the Free Form Construction Result has been set to Plane in the Modeling Preferences dialog. OK the dialog.

1376

Creating Ruled Sheet Bodies with Parameter Alignment Starting the Ruled Feature You will create ruled sheet bodies using parameter alignment.

Choose the Ruled icon

or Insert

Free Form Feature

Ruled.

The Ruled dialog of string selection options displays, so you can select the first string. The first string can consist of a point, or one or more curves, solid edges, and solid faces. Select this string at the right end of the string, and choose OK.

Your direction vector should point toward the left. (If you selected the line at the other end of the string, the vector will point in the opposite direction.)

1377

Creating Ruled Sheet Bodies with Parameter Alignment Selecting the Last Section String You can now specify the second section string. Another dialog of string selection options displays. Both direction vectors must point in the same general direction, or your final sheet body will be twisted. The second string can consist of curves, solid edges, and solid faces. Select the next string and choose OK twice.

Creating Ruled Sheet Bodies with Parameter Alignment Specifying Parameter Alignment A Ruled dialog displays default parameters.

1378 The Parameter alignment spaces the points, through which the isoparametric curves will pass, at equal parameter intervals along the strings. The entire length of each curve will be used.

Use the Parameter alignment option. OK the dialog. The ruled feature is created.

This ruled feature has a planar surface because the Modeling Preferences were set to Plane as the Free Form Feature Construction Result. You may recall that many form features (such as a hole) must be placed on a planar placement face. If you thicken this (planar) ruled feature into a solid body, you could place features (such as a hole) on the body. Form features cannot be placed on B-Surfaces.

1379 You can create a ruled B-Surface sheet body with coplanar lines.

Creating Ruled Sheet Bodies with Parameter Alignment Setting Modeling Preferences for a B-Surface To create a B-Surface sheet body, you need to change the construction result option in the Modeling Preferences dialog and create another ruled sheet body. Choose Preferences

Modeling.

Choose the Free Form tab on the dialog. Set the Free Form Construction Result to B-Surface and OK the Modeling Preferences dialog.

Creating Ruled Sheet Bodies with Parameter Alignment Creating the B-Surface Feature Now, create another ruled sheet body using these two strings. (When you get a dialog of Boolean operations, choose the Create option.)

The ruled feature is complete.

1380

Creating Ruled Sheet Bodies with Parameter Alignment Finding Information on the Object Choose Information

Object.

Choose Type on the Class Selection dialog. Choose Face and OK the Select by Type dialog. Select both faces and OK the Class Selection dialog. The Information window displays information that shows the first sheet body has a planar surface, and the second sheet body has a B-Surface surface. Close the Information window and Refresh the view. You cannot create a ruled sheet with interior boundaries, which would result in holes. To do this, you would have to create a bounded plane, which is described in another lesson.

Creating Ruled Sheet Bodies with Parameter Alignment Creating Another Ruled Sheet Body Zoom in on the area shown below. Select the three curves in the first string and confirm the selection. Select the two curves in the second string and confirm the selection. Make sure the direction vectors point in the same direction, and use the defaults in the Ruled feature dialog.

1381

Choose OK until the ruled feature is created, remembering that the Boolean options will appear because multiple bodies exist. A ruled feature is created.

Because these curves are not coplanar, a B-Surface ruled sheet was created. Also, even if these lines had been coplanar, a B-Surface would have still been created because the Modeling Preferences settings are set to B-Surface type. You could continue to create ruled sheets using the remaining strings. Close all part files.

Creating a Ruled Body using By Points Alignment In this activity, you will create a ruled feature using the By Points alignment.

1382

Creating a Ruled Body using By Points Alignment Opening the Part Open part file fff_ruled_by_points.prt from the fff subdirectory, and start the Modeling application.

Set the U Count and V Count in the General Modeling Preferences to 10. Set the Free Form Modeling Preferences to the Free Form Construction Result of Plane and OK the dialog.

Creating a Ruled Body using By Points Alignment Selecting Section Strings Choose the Ruled icon

or choose Insert

Free Form Feature

Ruled.

1383 A Ruled dialog displays. Because the strings consist of closed coplanar curves, and the Modeling Preferences body type is set to solid, a solid body will be created. You will be able to select the strings without using the dialog. In a counterclockwise direction, select the three lines in the first string, and choose OK. In a counterclockwise direction, select the four sections in the second string, and choose OK twice.

Direction vectors should point in approximately the same direction.

Creating a Ruled Body using By Points Alignment Specifying By Points Alignment The By Points alignment option lets you align sharp corners of section strings. When the section strings contain sharp corner(s) (like in this part), you can use the By Points alignment to preserve the sharp corners.

1384 All the sections should contain at least one alignment point, and the same number of alignment points must be present in each section string. The starting and ending points cannot be selected as alignment points. You will need to use the By Points option. Change Alignment to By Points. Use the tolerance value of 0 (zero). OK the dialog.

Creating a Ruled Body using By Points Alignment Selecting the First and Second Set of Points

You are now prompted to select alignment points. Select the point on the first string and the point on the second string.

The number 1 appears at the two points.

Select the next pair of alignment points. (For the first point, you need to select the same

1385 point on the triangle that you selected before.)

These points are numbered in the view.

Creating a Ruled Body using By Points Alignment Selecting the Third Set of Points Select the third set of alignment points.

1386 The number 3 appears at the two points.

Creating a Ruled Body using By Points Alignment Completing the Model

You have specified all alignment points. You do not have to specify the ending alignment points because the system does this for you. Choose OK in the dialog. Regenerate the work view. Cancel the dialog. The solid ruled feature is created.

1387 Close all part files.

Through Curves This lesson covers creating free form features Through Curves.

Through Curves lets you to create a sheet or solid body through a set of section strings. The section strings define the rows of the body. It is similar to Ruled features, except you use more than two section strings.

Creating a Single Patch, Parameter Alignment Sheet Body In this activity, you will create a Through Curves sheet body with a single patch, and use Parameter Alignment.

1388

Creating a Single Patch, Parameter Alignment Sheet Body Opening the Part Open part file fff_thrucurves_parameter.prt from the fff subdirectory, and start the Modeling application.

Creating a Single Patch, Parameter Alignment Sheet Body Starting the Feature Choose the Through Curves icon Curves.

or Insert

Free Form Feature

Through

1389 The Through Curves dialog lists section string options: Solid Face, Solid Edge, Curve, and Chain Curves. In complex parts, you will want to choose an option from the Through Curves dialog, and then select the string. A section string can consist of one or more curves, solid edges, or solid faces. The strings define the rows (U direction) of the body. The strings and the body are associative; therefore, when you modify the string(s) the body changes. You need to select the first section string. Select the first section string and choose OK.

A direction vector displays at the end of the string.

Creating a Single Patch, Parameter Alignment Sheet Body Selecting the Remaining Section Strings Repeat the selection and confirmation for each of the remaining strings, remembering that you need to select strings at similar ends. Five vectors are displayed.

1390 Remember, vectors must be located at the same ends of the strings and point in about the same direction or a twisted shape will be created. (If they are not pointing in the direction, cancel the dialog and try it again.) Choose OK to confirm that all strings are selected.

Creating a Single Patch, Parameter Alignment Sheet Body Specifying a Single Patch A Through Curves dialog displays parameter options.

Single patches were described in the lesson on Through Points. A Single patch through curves feature can have from 2 to 25 strings. Choose the Single patch type on the Through Curves dialog. You cannot close single patch features in the V direction, so the Closed in V option is grayed out. The V Degree is grayed out because, for single patch bodies, the system will calculate the V degree to be equal to the number of section strings minus one. Since you selected 5 section strings, the V degree will be 4. When you use multiple patches, you have an option to close the part in the V direction. You must specify a V degree of 1 or greater. The V degree must be a number from 1 to 24, and must be smaller than the number of strings used.

1391

More About Closed Bodies in the V Direction

The Closed in V toggle lets you close a sheet along columns (V direction) as shown below.

Closed in U - If the strings you select are all closed, the body generated will be closed in the U direction. The closed status of the body along rows (U direction) is based on the closed status of the selected section strings.

For a multiple patch body, the number of strings that you must specify is dependent upon the degree. The degree affects the shape of the model, as shown below. For example, multiple patch and a degree of one creates linear segments between the curves.

Creating a Single Patch, Parameter Alignment Sheet Body Specifying the Parameter Alignment The alignment methods let you control the alignment between selected curves in the section strings.

1392 The Parameter alignment spaces the points, through which the isoparametric curves will pass, at equal parameter intervals along the strings. The entire length of each curve will be used.

Use the Parameter alignment. When the Simple option (near the bottom of the dialog) is toggled on, the system tries to build the simplest surface possible and minimizes the number of patches. Toggle on the Simple option near the bottom of the dialog.

Creating a Single Patch, Parameter Alignment Sheet Body Completing the Feature Tolerance is the maximum distance between the input geometry (strings in this case) and the resulting body. The value is defaulted to the specified Distance Tolerance value in the Modeling Preferences dialog. Use .001 as the Tolerance value. Choose OK on the Through Curves dialog. Because you chose Simple as a surface creation technique, you can now select a template curve that will be used during surface creation. You are prompted to select a template curve.

1393 If you choose not to specify a template string, by choosing OK on the dialog, the system will choose the most complicated string for you. Choose OK to indicate that you will not be selecting a template curve. The single patch sheet body is created with a U degree and V degree of 4. When Simple is toggled off, the U degree will be 3, and the V degree will be 4.

Cancel the dialog. The section strings and the newly created body are associated. If you change one of the section strings used to create the feature, the body will update. Close all part files.

Creating a Multiple Patch Sheet Body Using Arclength Alignment You will create a sheet body through curves, using arclength alignment. Then, you will compare it with the other one that has a parameter alignment.

1394

Creating a Multiple Patch Sheet Body Using Arclength Alignment Opening the Part Open part file fff_thrucurves_arclength.prt from the fff subdirectory, and start the Modeling application. Shade the model to see the green sheet body.

1395 Return to Wireframe display.

Creating a Multiple Patch Sheet Body Using Arclength Alignment Starting the Feature

Choose the Through Curves icon Curves.

or Insert

Free Form Feature

Through

You will use the lower two strings to create a sheet body. Each of the two lower strings are composed of three curves. You must select all curves in each string. Working from right to left, select the three curves in the bottom string and choose OK.

A direction vector displays at the beginning of the string. It should be pointing to the left.

Creating a Multiple Patch Sheet Body Using Arclength Alignment Selecting the Last Section String Now, you need to select the second curve string. Select the three curves in the upper string, beginning at right and moving to the left.

Choose OK twice (once to confirm the selection of the string, and once to confirm that all

1396 strings have been selected). Two direction vectors display.

Check the direction vector orientation. (They should be pointing in approximately the same direction or the sheet will be twisted.)

Creating a Multiple Patch Sheet Body Using Arclength Alignment Specifying an Arclength Alignment A Through Curves dialog display parameter options. The Arclength alignment option spaces the points, through which the isoparametric curves will pass, at equal arclength intervals along the defining curves. The entire length of each section string will be used, as shown below.

You need to specify an alignment option. Choose the Arclength alignment option. Toggle off the Simple option.

1397 Set the Patch Type to Multiple.

Creating a Multiple Patch Sheet Body Using Arclength Alignment Specifying the Degree of One Notice that the V Degree is 1. This is the way the part was last saved. The sheet at the top of the graphics screen was created with Parameter alignment, multiple patch, and V degree of 1. Choose OK on the dialog. Choose Create. (The system recognizes the other sheet body.) The sheet is created. Set the display mode to Shaded. Whether you use Parameter or Arclength alignment is based on your design and manufacturing requirements. Each alignment produces different results. One way to see these visual differences between the two sheets is to shade them. As you can tell, the surfaces are different.

Notice the differences and then return to a wireframe display.

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Creating a Multiple Patch Sheet Body Using Arclength Alignment Finding Information on the B-Surface You can also use Information Choose Information

B-Surface to provide other important data.

B-Surface.

Make sure all three B-Surface Analysis dialog options are toggled on, and choose OK on the dialog. Select both sheet bodies, and choose OK. The Information window displays the number of patches, seams, degrees, etc. One of the important differences between the two sheet bodies in this part file is the continuity at the seams of the patches: C1 = slope continuous, C2 = curvature continuous, C0 = contiguous. Review the data in the Information window, and then close it. In the view, you can visually compare the alignment for the Parametric and Arclength methods. Remember, your design intent, and manufacturing considerations will influence your decision as to which alignment option to use.

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Creating a Multiple Patch Sheet Body Using Arclength Alignment Analyzing the Arclength and Parameter Alignment Options Refresh the view. Choose Analysis

Face

Radius and use the default values.

Select both sheet bodies, and choose OK. If you are using a 3D graphics driver in your system, you may see shaded images like these.

Rotate the view to visually compare the sheets and curves and cancel any dialogs. Close all part files.

Creating a Sheet with By Points Alignment with a Degree of One In this activity, you will create a through curves sheet body using By Points alignment. Then, you will edit the feature, changing the degree to 2.

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Creating a Sheet with By Points Alignment with a Degree of One Opening the Part Open part file fff_thrucurves_by_points.prt from the fff subdirectory, and start the Modeling application.

You will use three strings of curves to define the shape of the sheet body.

Creating a Sheet with By Points Alignment with a Degree of One Starting the Through Curves Feature

Choose the Through Curves icon Through Curves.

or choose Insert

Free Form Feature

For this feature, you will be selecting three strings, each with three sections. Select the three section curves in the first string and choose OK. (A direction vector will

1401 display, pointing upward.)

Select the three section curves in the second section string and choose OK. Select the three section curves in the third section string and choose OK. Your vectors should display like this.

Choose OK to confirm that all strings have been selected.

Creating a Sheet with By Points Alignment with a Degree of One Specifying the Multiple Patch Type, By Points Alignment, and Degree of 1 Use the default, Multiple patch option. The By Points alignment option lets you specify the specific alignment points between section strings. When the section strings contain sharp corner(s) (like in this part), you can use the By Points alignment to preserve the sharp corners.

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All the sections should contain at least one alignment point, and the same number of alignment points must be present in each section string. The starting and ending points cannot be selected as alignment points. You will need to use the By Points option to align the corners correctly. Choose the By Points Alignment option. Toggle off the Simple option. Use the Multiple patch type. To create a very stiff shape, multiple faces, and sharp edges on the body, you need to use a V degree of 1. Double-click in the V Degree field and key in 1 as the degree. Notice that the Tolerance is 0. Because the selected section strings contain sharp corners, it is recommended that you use a zero tolerance for an exact fit, and to preserve sharp corners. The system will create separate faces joined with sharp edges. Choose OK.

Creating a Sheet with By Points Alignment with a Degree of One Selecting the First Set of Alignment Points You need to select the alignment points that tell the system how to connect the ends of the curves in the section strings. Select the curve endpoints shown below to specify the first set of alignment points.

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A number 1 appears at the ends of the selected curves to specify the first set of alignment points.

Creating a Sheet with By Points Alignment with a Degree of One Selecting the Second Set of Alignment Points You can specify the next set of points in the same direction as the last set of points. Select the curve ends to specify alignment for the second set of points.

1404 The number "2" should display at the vertex of each of your selections. Choose OK in the dialog to confirm that all points have been selected. The model is created with sharp corners at the alignment points.

Cancel the dialog.

Creating a Sheet with By Points Alignment with a Degree of One Changing the Degree from One to Two Separate faces are formed between the sharp corners in this part. The degree of 1 created the stiffer faces of the free form feature. The zero tolerance maintained the sharp edges. You will change the degree from one to two and update the feature.

Choose the Edit Feature Parameters icon

or Edit

Feature

Choose THROUGH_CURVES feature and choose OK. A dialog of editing options for this feature displays. Choose Edit V Degree. The current V Degree of 1 displays in the field on the dialog. Change the V Degree to 2 and choose OK. Choose OK on the list of edit options.

Parameters.

1405 Choose Apply. The model is updated.

Notice the change in the shape of the faces of the model. Closed Body Using Alignment by Points

An example of a solid body created with alignment by points is illustrated below.

To align points in the above example, you would need to select points from each section string, selecting the point for the first and second points at the same location. The starting location of the string does not have to be selected.

1406 Close all part files.

Creating a Sheet Body with Tangency Constraints In this activity, you will create a through curves feature that is tangent to two adjacent faces.

Creating a Sheet Body with Tangency Constraints Opening the Part Open part file fff_thrucurves_tangent.prt from the fff subdirectory, and start the Modeling application.

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Creating a Sheet Body with Tangency Constraints Starting the Feature

Choose the Through Curves icon Curves.

or Insert

Free Form Feature

Through

You need to make the string selections. Starting at the left yellow string, select and OK each of the five section strings so that vectors display like this.

Choose OK to confirm all strings are selected. The Through Curves dialog displays options for Patch Type, Alignment, and all other options that you have seen before.

Creating a Sheet Body with Tangency Constraints Specifying the Patches, Alignment, Tolerance, and Tangency Use the Multiple patch type. Use the Parameter alignment option. Use a V Degree of 3. Use the default tolerance value. Toggle off the Simple option. You can apply tangency or curvature constraints to the first and/or the last selection string of the feature. If you were to create it using No Constraint, you would get this type of non-tangent condition between the sheet bodies.

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You will apply tangency constraints. Change the First Section String to have Tangency constraints. Change the Last Section String to have Tangency constraints. You can specify that the direction of the tangency be Not Specified, Isoparametric, or Normal. Use Not Specified for the Direction. Choose OK on the dialog.

Creating a Sheet Body with Tangency Constraints Selecting Tangent Faces Now, you need to select the face for the first tangent face (tangency string constraint). Select the face adjacent to the first section string and choose OK.

And, you need to select the face for the second tangent face. Select the face adjacent to the last section string to specify the tangency constraint for the last string and choose OK.

1409

Creating a Sheet Body with Tangency Constraints Completing the Model Choose Create on the dialog of boolean options. The finished part is a free form multiple patch sheet body created Through Curves that is tangent to the two adjacent faces.

Rotate, Shade, find information on the sheet, and analyze the face curvature. Close all part files.

Creating a Solid Body Using Spline Points Alignment In this activity, you will create a through curves free form feature using the Spline Points alignment option.

1410

Creating a Solid Body Using Spline Points Alignment Opening the Part Open part file fff_thrucurves_spline_points.prt from the fff subdirectory, and start the Modeling application.

Creating a Solid Body Using Spline Points Alignment Starting the Feature Choose the Through Curves icon Curves.

or Insert

Free Form Feature

Through

When you create a Spline Points feature, the section strings must be single B-curves each with the same number of defining points. In this part, the section strings meet these conditions. Select each of the strings, and confirm each selection.

1411

Make sure the direction vectors point in the same direction, otherwise your part will be twisted. Choose OK after all seven section strings have been selected.

Creating a Solid Body Using Spline Points Alignment Specifying the Alignment The Spline Points alignment option creates a surface using points and tangent values for the input curves. The new surface is required to pass through the points that define the input curves, and not the curves themselves. This changes the curve parameters and creates a smooth surface. When the curve parameters are changed, the tangent values remain the same. Use a Multiple patch type. Choose Spline Points alignment. Use a V Degree of 3. Choose OK to create the body. The feature is created.

1412

If you were to create this feature using the Parameter alignment, you would have a higher number of faces and patches with a zero tolerance, making the faces more complex. Using spline points simplifies the faces, while maintaining zero tolerance. Cancel the dialog and close all part files.

Creating a Through Curves Feature Selecting Multiple Faces In this activity, you will create a through curve sheet that is curvature continuous with the top 2 sheets, and the 3 vertical sheets.

1413

Creating a Through Curves Feature Selecting Multiple Faces Opening the Part Open the part file fff_thrucurves_faces.prt from the fff subdirectory, and start the Modeling application.

Choose the Through Curves icon Curves.

or Insert

Free Form Feature

The direction vector displays along the edges in the view. Remember, all direction vectors need to point in the same direction.

Creating a Through Curves Feature Selecting Multiple Faces Selecting the First Section String

You need to select the first section string. Select this edge for the first part of the first section string.

Through

1414

Select the next edge for the first section string and choose OK.

Creating a Through Curves Feature Selecting Multiple Faces Selecting the Second and Last Strings You need to select the next section string. Select the curve at the left most location for the second section in the second string and choose OK. Now, two direction vectors display.

1415

Now, you need to select the three edges of the lower sheet body. This will form the last of the three section strings. Being careful to select starting at the left, select the top edges of the last set of faces, and choose OK. Three direction vectors should be displayed.

Choose OK.

Creating a Through Curves Feature Selecting Multiple Faces Specifying Patches, Alignment, Degree, and Continuity The Through Curves dialog displays.

1416 Use Multiple Patch Type. Use Parameter Alignment. Use a V Degree of 2. Set the First and Second Section String options to Curvature continuous. OK the dialog. You must specify the tangent faces for the first string. When prompted for the constraint on the first section string, select the two top faces and choose OK.

Now, you must specify the tangent faces for the second string. When you are prompted to select the constraint on the last section string, select the three vertical faces and choose OK. The model is complete. Cancel the dialog. You can use the Analysis Face Remember to select all faces.

Reflection to analyze the surfaces for reflections.

1417

Close all part files.

Through Curve Mesh This lesson covers creating features through a mesh of curves. The Through Curve Mesh option lets you create a body from a set of existing strings that consist of one or more curves, solid edges, or solid faces.

1418

Creating a Curve Mesh with Strings and a Point In this activity, you will create this free form sheet body, using primary and cross strings.

1419

Creating a Curve Mesh with Strings and a Point Opening the Part Open part file fff_curvemesh_1.prt from the fff subdirectory, and start the Modeling application.

The modeling preferences for U and V grid counts have been set to 15. (You can check this by choosing Preferences Modeling.)

Creating a Curve Mesh with Strings and a Point Starting the Feature

1420

Choose the Through Curve Mesh icon Curve Mesh.

or Insert

Free Form Feature

Through

A Through Curve Mesh dialog displays primary string selection options.

Creating a Curve Mesh with Strings and a Point Specifying the First Primary String

Primary and cross strings are required. Primary strings should run in approximately one direction. You can use from 2 to 150 primary strings. You need to select the primary section strings. You can select a point as the first and/or last primary string. If you have several primary strings, selecting the point as the last primary, will make editing the sheet body easier. Remember to select the same ends so that the part does not twist. Select the first primary string and choose OK.

1421

A direction vector displays on the primary string.

Creating a Curve Mesh with Strings and a Point Selecting a Point as the Second Primary String

In this model, you will be selecting a point as the last primary string. Choose Point from the dialog. Select the point as the last primary string.

1422

Because you selected a point, the system knows that this is the last primary string; so, you will not have to OK the selection. To create a closed body, the primary strings must form a closed loop. You must also reselect the first cross string as the last cross string.

Creating a Curve Mesh with Strings and a Point Specifying Cross Strings After selecting all primary strings, you need to select the cross strings. Cross strings must be tangent or curvature continuous, and must run approximately perpendicular to the primary strings. Select the first cross string and choose OK to confirm the selection.

Just as in selecting primary strings, you must select the cross strings in an orderly manner, moving from one side of the body to the other. Remember to select at the same ends of the cross strings.

1423 Select each of the remaining cross strings, and choose OK after each selection.

Choose OK to confirm that all cross strings have been selected. There is no spine string in this part file. However, if you needed to use a spine string, you would select it now. The spine string controls the parameterization of the cross strings, and can improve the surface smoothness. The spine string must be roughly perpendicular to all primary strings. Spine curves are invalid if they are all, or in part, perpendicular to the cross strings. This is because the intersection between the section planes and the cross string (defining curves) will be nonexistent or poorly defined. Choose OK to indicate that no spine string exists and all strings have been selected.

Creating a Curve Mesh with Strings and a Point Specifying Parameters for the Feature

The Through Curve Mesh dialog displays.

1424

The system lets you control the emphasis of the sheet body. Use the Both emphasis option. Use 0.02 as the tolerance value. The system lets you constrain the first and last primary and cross sections of the curve mesh surface with tangent continuous or curvature continuous options. Because you will not constrain the new surface to any adjacent surface, you can use the No Constraint option.

Creating a Curve Mesh with Strings and a Point Construction Options You can use one of three construction options when you create a Through Curve Mesh feature: Normal, Use Spline Points, and Simple.

Curve Mesh Construction Options

Normal - Lets you constrain the first and last primary and cross strings with either tangent or curvature continuous constraints. This is useful where you want to maintain surface continuity between the new surface and adjacent surface(s).

1425 Use Spline Points - Lets you create a body using the points and tangent values at the points for the input curves. For this option, the selected curves must be single Bcurves with the same number of defining points. The curves are temporarily reparameterized through their defining points (retaining any user-defined tangent values). These temporary curves are then used to create the body. This can help create a simpler body with fewer patches. Simple - Lets you create the surface without specifying constraints. It is for use when the curves you are selecting have different segments. If turned on, the system will find the most complex curve and use it as a template to change the other curves to match its segments.

You will not be using Spine Points. Use the Normal Construction option. Choose OK on the dialog. The curve mesh body created is a polynomial bi-cubic. This means that its degree is cubic, a degree of 3, in both the U and V directions.

Cancel the dialog. Close the part file.

Creating a Curve Mesh with Emphasis on Primary and Cross Strings In this activity, you will create a curve mesh between primary and cross strings that do not meet. When a situation like this occurs, you can control where the sheet is located by using the emphasis options: Primary, Cross, or Both. You will create a curve mesh feature, applying emphasis on both primary and cross strings.

1426

Emphasis refers to the strings that have the most influence over the final shape of the feature. If all three Through Curve Mesh Emphasis options are used on this model, three different features will be created.

Creating a Curve Mesh with Emphasis on Primary and Cross Strings Opening the Part Open part file fff_curvemesh_2.prt from the fff subdirectory, and start the Modeling application.

1427

Creating a Curve Mesh with Emphasis on Primary and Cross Strings Finding the Distance between Primary and Cross Strings Make layer 2 the work layer so that the sheet body is on a different layer than the curves. Notice that the endpoints of the strings do not intersect.

You need to find the distance between the two endpoints of the primary and cross string. Then you can use the distance value as the tolerance value when you create a body using the Both emphasis option. Choose Analysis

Distance.

Select the right endpoints of the strings.

A information window displays the minimum distance of .250 inches. Cancel the dialog. Close the information window.

Creating a Curve Mesh with Emphasis on Primary and Cross Strings Specifying Primary Strings

1428

Choose the Through Curve Mesh icon Curve Mesh.

or Insert

Free Form Feature

Through

The dialog of selection options displays for the selection of the first primary string. Select this primary string and choose OK.

Select the other primary string and choose OK. The vectors must point in about the same direction, like this.

Choose OK twice to confirm that all primary strings have been selected.

Creating a Curve Mesh with Emphasis on Primary and Cross Strings Specifying Cross Strings Now, you can specify the cross strings. Select each cross string, choosing OK after each selection.

1429

When you have selected all cross strings, choose OK. This would be the time for you to specify a spine string, if you were going to use one. This part does not have a spine string, so choose OK to confirm that you have selected all strings.

Creating a Curve Mesh with Emphasis on Primary and Cross Strings Specifying Emphasis and Tolerance The Emphasis setting (primary, cross, or both) determines which set of strings will have the most effect over the shape of the curve mesh body. Emphasis has a bearing if primary and cross string sets do not intersect, in which case the resulting body will pass through the specified emphasis strings: primary, cross, or both. Because the distance between the body and its strings is controlled by the tolerances, the body will not pass through the strings exactly. For this sheet body, you will place emphasis on both sets of strings. Use the Emphasis of Both. The Intersection Tolerance is defaulted to 0.02. The tolerance is used to check primary and cross string intersection. Strings must intersect within tolerance or a body will not be created, and a message will display. The tolerance should be equal to, or greater than, the minimum distance between the primary and cross strings. Remember, the distance between the strings was .250, so you must set the tolerance to a value of .250, or greater. You need to use a tolerance value that is large enough to include the ends of the cross and primary strings.

1430 Change the Tolerance value to .25. Use No Constraint for all strings. Use the Normal construction option and choose OK. The sheet body is created midway between the primary and secondary strings because you selected Both as the emphasis.

Cancel the dialog. Close the part file.

Creating a Curve Mesh with Emphasis on Primary Strings In this activity, you will create a sheet, placing emphasis on the primary strings.

Creating a Curve Mesh with Emphasis on Primary Strings Opening the Part Open part file fff_curvemesh_2a.prt from the fff subdirectory, and start the Modeling

1431 application.

Creating a Curve Mesh with Emphasis on Primary Strings Starting the Feature Choose the Through Curve Mesh icon Curve Mesh.

or Insert

You are prompted to select the strings. Select and confirm each primary string.

Choose OK to end the primary string selection. Select and confirm each cross string.

Free Form Feature

Through

1432

When you have selected all cross strings, choose OK to tell the system that you have completed all cross string selections. You are prompted for a spine string. Choose OK, because there is no spine string to select.

Creating a Curve Mesh with Emphasis on Primary Strings Specifying Emphasis and Tolerance Choose Primary for the Emphasis option. Change the tolerance to .250. Use No Constraint for all strings. Use the Normal construction option. OK the dialog. A list of Boolean operations displays, because a sheet body is present on layer 2. (That body was created using the Both emphasis option.) Choose Create on the boolean operations dialog. Notice that the sheet you just created is closely aligned with the primary strings that you selected.

1433

Cancel the dialog. Layer 2 contains the sheet body created using the Both emphasis option. Make layer 2 selectable and compare the two sheet bodies. Close the part file.

Creating a Curve Mesh with Emphasis on Cross Strings In this activity, you will create a sheet, placing emphasis on the cross strings.

Creating a Curve Mesh with Emphasis on Cross Strings Opening the Part and Starting the Feature Open part file fff_curvemesh_2b.prt from the fff subdirectory, and start the Modeling application.

1434

Choose the Through Curve Mesh icon Curve Mesh.

or Insert

Free Form Feature

Creating a Curve Mesh with Emphasis on Cross Strings Selecting Primary Strings You need to select the primary strings. Select and confirm each of the primary strings.

Choose OK to confirm the primary string selection. Select and confirm each cross string.

Through

1435

Choose OK to confirm all cross string selections. Choose OK to confirm that no spine string will be used.

Creating a Curve Mesh with Emphasis on Cross Strings Specifying Emphasis and Tolerance Choose Cross for the Emphasis option. Change the tolerance to .25. Use No Constraint for all strings. Use the Normal construction option. OK the dialog. The Boolean options dialog displays, because other sheet bodies exist in the part file. Choose Create on the dialog of boolean operations. Cancel the dialog. Notice that the new sheet is closely matched to the cross strings.

1436

Creating a Curve Mesh with Emphasis on Cross Strings Comparing Various Emphasis Options You can compare three sheet bodies, each created with a different Emphasis option. Make layers 2, and 3 selectable. Two other sheets display. Compare the three sheet bodies, noticing gaps and how the sheets are aligned with the section strings used to create them.

The creation strings and the new bodies are associative. Therefore, if you change the strings, the bodies will change, when updated. Cancel all dialogs. Close all part files.

Creating a Curve Mesh with Tangency Constraints In this activity, you will fill the central area of the model with a curve mesh sheet that is tangent to primary and cross faces.

1437

Creating a Curve Mesh with Tangency Constraints Opening the Part Open part file fff_curvemesh_3.prt from the fff subdirectory, and start the Modeling application.

Shade the model. Notice that there is an area within the model where no sheet body exists. Return to a wireframe display. You will create a curve mesh sheet body and apply tangency constraints so that the new feature has a tangent continuous condition relative to the adjacent faces.

Creating a Curve Mesh with Tangency Constraints Specifying Primary Strings Choose the Through Curve Mesh icon Curve Mesh.

or Insert

Free Form Feature

Through

You will use three primary strings this time. Select the first primary string, and choose OK. (You may want to zoom in a little.)

1438

Select the second primary string, and choose OK. Select the third primary strings, and choose OK. Remember to check that the direction vectors are pointing in the same direction. (Back up and reselect primary strings if you do not have all direction vectors pointing in the same direction.) After you have selected all three primary strings, choose OK to complete the primary string selection.

Creating a Curve Mesh with Tangency Constraints Specifying Cross Strings You will use two cross strings for this feature. Select the first cross section string, and choose OK. Select the second cross string and choose OK twice to confirm that all cross strings have been selected. You will not use a spine, so choose OK when you are prompted for a spine string.

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Creating a Curve Mesh with Tangency Constraints Specifying Emphasis, Tolerance, and Tangency A Through Curve Mesh dialog displays. Use Both for the Emphasis option. Use a Tolerance value of .02 which will be large enough for this part. Use the Normal construction option. You can add Tangency or Curvature continuity on the first and/or last primary strings, and on the first and/or last cross stings. You are allowed to select more than one face for tangency or curvature constraint. The Curvature option constrains the new body tangent to, and curvature continuous with, a selected adjacent face. When these constraints are created, they match the tangency and the normal curvature, in the tangent direction of the new body. The Tangency option constrains the new body tangent to a selected adjacent face. The Tangency constraint option causes the new curve mesh feature to match neighboring surfaces smoothly, with a tangent continuous condition. There will be an associativity of the curve mesh surface to its neighbors when these constraints are applied. You will be creating a tangent condition with adjacent faces. Change all four options to read Tangency. You can match the constraints along common edges, as well as when the edges of the curve mesh body are in the interior of the constraint body. Choose OK in the Through Curve Mesh dialog.

Creating a Curve Mesh with Tangency Constraints Selecting Tangent Faces for Primary Strings Now, you need to select a tangent face for the first primary string. Select the tangent face to constrain the first primary string, and choose OK.

1440

Select the tangent face that will be used as a constraint on the last primary string, and choose OK.

Creating a Curve Mesh with Tangency Constraints Selecting Tangent Faces for Cross Strings Now, you need to select the faces that are tangent to the cross strings. Select the face for the constraint on the first cross string, and choose OK.

You only need to select one more face. Select the face for the constraint on the last cross string, and choose OK.

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Creating a Curve Mesh with Tangency Constraints Completing the Model You are provided with Boolean options. You could unite the new sheet with another, or create it separately. Choose Create on the dialog of boolean operations. Cancel the dialog. After the Through Curve Mesh feature is created, you could change the type of constraint (tangency/curvature) by editing the through curve mesh using Edit Feature Parameters. The shaded image will look like this.

Close all part files.

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Swept This lesson covers creating Swept features. A Swept feature is a body swept out by section strings (outlines) moving along guide strings (paths). Swept features can be sheet or solid bodies.

You can use the Swept option to create closed bodies.

About Creating Closed Swept Features If all guide string(s) form closed loop(s), the first section string can be reselected as the last section string to close the part, as shown here.

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Using 2 Guide Strings and 1 Section String In this activity, you will create two features using two guide strings. One of the sheets will have lateral scaling and the other will have uniform scaling.

Using 2 Guide Strings and 1 Section String Opening the Part Open part file fff_swept_2_guide_1_section.prt from the fff subdirectory, and start the Modeling application.

1444

Make layer 20 the work layer. Three strings exist. Two curves will be used as guide strings, and one will be used as a section string.

Choose the Swept icon

or Insert

Free Form Feature

Swept.

Using 2 Guide Strings and 1 Section String Starting Guide and Section Strings Notice that each string consists of only a single curve. A Swept dialog lists selection options. For swept features, 1 to 3 guide strings can be used. Guide strings can have many segments. Each segment can be either a curve, solid edge, or a solid face. Guide string segments must be smooth and continuous. Select and OK each of the two guide strings.

Choose OK to indicate that all guide strings have been selected. A section string can consist of one or more curves, solid edges, and solid faces. Section strings do not have to be smooth. Up to 150 section strings can be used in swept features.

1445 The section and guide strings do not have to intersect. Select the section string and choose OK twice. The direction vector displays on the section string.

The Swept dialog displays alignment methods and a default tolerance.

Options on the Swept Dialog

The Alignment Methods control the spacing of isoparametric curves between the section strings. (Alignment methods were discussed in the lesson on Through Curves.) Tolerance is the maximum distance between the strings and the resulting body. The default value is the Modeling Preferences Distance Tolerance. To create a body where you have an exact fit, you can enter a tolerance value of zero. For example, if the section strings contain sharp corners that you want to maintain, then use a tolerance of 0.0.

1446 Choose OK to accept the defaults on the Swept dialog.

Using 2 Guide Strings and 1 Section String Specifying Orientation and Uniform Scaling When two guide strings are used, you can scale the feature laterally or uniformly. (Scale Laterally, or Scale Uniformly options display on the dialog.) Scale Laterally scales the section string between the guide strings, but not vertically. When you use two or more guide strings, the orientation and scaling are constrained to follow the guides. The orientation and scaling will be specified with the use of two guide strings. When you use two or more guide strings, you cannot specify a scale factor. Scaling allows the section string to increase or decrease in size as it is swept along the guide.

Swept Scale Options

When specifying only one guide string, you can also impose scaling control. The Constant scaling option lets you enter a scale factor that will remain constant along the entire guide. If you enter a scale factor other than 1.0, the system scales the section string prior to sweeping. It is important to note that the section string is scaled about the point at the start of the guide. The Blending Function scaling option allows for linear or cubic scaling between specified starting and ending scale factors, which correspond to the start and end of the guide string. The Another Curve option is similar to using another curve for orientation control, but here the scale at any given point is based on the length of the ruling between the guide string and the other curve or solid edge.

1447 The A Point option is like the Another Curve option but you would use a point instead of a curve. Choose this form of scale control when you are also using the same point for orientation control (in the construction of three-sided swept). The Area Law scaling option lets you use the Law Subfunction dialog to control the cross sectional area of the swept body. The Perimeter Law scaling option lets you define a law curve to control the perimeter along the sweeping direction.

You will scale uniformly in all directions. Choose Scale Uniformly. A spine string may be used to further control the orientation of the section as it sweeps out the body. You have the option of selecting a spine string. Choose OK to indicate that you will not be selecting a spine string.

Notice how the scaling was performed.

Using 2 Guide Strings and 1 Section String Creating the Feature with Lateral Scaling Next, you will create the feature using lateral scaling. First, Blank the current sheet body. Choose Edit

Blank

Blank and select the sheet body, and choose OK.

Select and OK each of the two guide strings on the XC-YC plane. Choose OK to indicate that all guide strings have been selected.

1448 Select the section string, and choose OK twice. The Swept dialog displays. Choose OK to accept the defaults. The scale methods display. Choose the Scale Laterally scaling option, and choose OK because you will not use a spine. Choose Create and then Cancel the dialog. This sheet looks considerably different from the last sheet you created.

Using 2 Guide Strings and 1 Section String Comparing the Two Features You can unblank the other sheet body and compare both sheets. Choose Edit

Blank

Unblank All of Part to see both sheets.

Notice that the section string is swept along the entire lengths of both guide strings for both sheet bodies that you created.

1449 Rotate the part and compare the differences in the sheet bodies. Close all part files.

Using 2 Guide Strings, 1 Section String, and 1 Spine String In this activity, you will create a swept feature using a spine string to further control the orientation and sweep.

Using 2 Guide Strings, 1 Section String, and 1 Spine String Opening the Part Open part file fff_swept_spine_used.prt from the fff subdirectory, and start the Modeling application. The part contains two guide strings, a section string, and a spine that is aligned parallel to the guide strings.

1450

Using 2 Guide Strings, 1 Section String, and 1 Spine String Starting the Feature Choose the Swept icon

or Insert

Free Form Feature

Swept.

You need to select the guide strings. Select and OK each of the two guide strings, and choose OK to complete the guide string selection.

You need to select the section strings. Select the section string and choose OK twice.

Choose OK to accept the defaults (parameter alignment and tolerance of 0.001) in the Swept dialog.

Using 2 Guide Strings, 1 Section String, and 1 Spine String Specifying a Scale and Spine String The dialog of scaling methods displays.

1451 Choose Scale Uniformly. A spine string helps to control the orientation of the section string(s).

Use of Spine Strings

Consider using a spine string when uneven parameterizations of the guide strings would result if no spine string were used. The spine string will eliminate the effects of guide parameterizations, thus allowing better sheet definition. A spine string is most effective when it is normal to the section string(s). A spine string might be needed in a situation like the one shown below.

You will select the spine string. Select the spine string as shown, and choose OK.

1452 The part is created. Notice that the body limits are controlled by the length of the spine curve.

Using 2 Guide Strings, 1 Section String, and 1 Spine String Comparing Scaling Options Notice that the section string is not swept along the entire lengths of both guide strings, but is limited by the spine curve.

Remember, you used uniform scaling for this feature. If you were to create this sheet with a lateral scaling and a spine string, the model would look like this.

Cancel all dialogs and Close all part files.

Using 2 Section Strings, 2 Guide Strings, and 1 Spine String In this activity, you will create a solid body using two closed section strings.

1453

Using 2 Section Strings, 2 Guide Strings, and 1 Spine String Opening the Part Open part file fff_swept_solid_body.prt from the fff subdirectory, and start the Modeling application.

Turn off the display of the WCS. You will create a solid body.

Using 2 Section Strings, 2 Guide Strings, and 1 Spine String Starting the Feature Choose the Swept icon

or Insert

Free Form Feature

Swept.

You need to select the guide strings. Remember to select the strings at similar ends. Select and OK each green guide string, then choose OK after both guides are selected. You need to select the section strings. A solid body is created if all section strings form closed planar faces, and the Modeling Preferences are set to Solid Body.

1454 Select all nine (9) curves in section string #1, and OK your selection. (You may want to zoom in on the area for a careful selection.)

The direction vector is shown below as pointing upward. Your vector may point in the opposite direction.

Using 2 Section Strings, 2 Guide Strings, and 1 Spine String Selecting the Last Section String As long as direction vectors of all section strings point in about the same direction, the part will not be twisted. Select the two (2) curves in section string #2, OK the selections, and OK that all section strings have been selected.

1455 If the arrows point in different directions, you do not need to cancel and reselect the strings. You can reselect the start of the string you just selected. To do this, select near the start of the curve on the side that you want the arrow to point.

Using 2 Section Strings, 2 Guide Strings, and 1 Spine String Specifying the Interpolation Method A Swept dialog lists two interpolation methods, because you selected more than one section string. Linear interpolation causes the rate of change from the first section string to the second to be linear function. Cubic interpolation causes the rate of change from the first section string to the second to be a cubic function.

The bodies above were each constructed from 2 section strings, 1 guide string, parameter alignment, tolerance of .001, fixed orientation, and constant scale of 1. You need to choose an interpolation method. Choose the Linear interpolation method. (Or OK the dialog if Linear is the default.)

1456

Using 2 Section Strings, 2 Guide Strings, and 1 Spine String Specifying Alignment, Tolerance, and Scale Method A Swept dialog displays alignment methods (Parameter, Arclength, and By Points) and a tolerance value. Because you used two section strings with different shapes, the By Points alignment method is available in the dialog. (Alignment options were discussed in the section on Through Curves.) Choose OK in the Swept dialog to accept Parameter alignment and .001 tolerance. The scale methods display in a dialog. You need to specify a scaling method. Choose Scale Laterally.

Using 2 Section Strings, 2 Guide Strings, and 1 Spine String Specifying a Spine String You will use a spine string to control the parameterization of this model. Select the cyan curve as the spine string and choose OK.

The solid body is created. Turn on the display of the WCS. Regenerate the work view.

1457

Cancel the dialog. Close all part files.

Using Faces as Section Strings In this activity, you will create a solid body between two existing bodies. You will select planar faces as the section strings and use two green splines for the guide strings.

Using Faces as Section Strings Opening the Part Open part file fff_swept_faces.prt from the fff subdirectory, and start the Modeling application.

1458

Using Faces as Section Strings Selecting Guide Strings You will create a swept solid feature between two faces of other two solid bodies.

Choose the Swept icon

or Insert

Free Form Feature

Swept.

You need to select the guide strings. Select and OK each guide string.

Choose OK to indicate that all guide strings are selected.

Using Faces as Section Strings Selecting the First Section String You need to select a face as the first section string. This part contains two solid bodies. You will sweep between the planar faces of the solid bodies. For the section string, choose Solid Face on the dialog, select the left face, and choose OK twice. (Zoom if needed.) Careful selection is important. Use Back if you need to reselect Face 1. The direction arrow should display. Depending on your cursor location, the vector may point upwards or downwards.

1459

Using Faces as Section Strings Selecting the Second Section String For the last section string, you can use a face on another body. Choose Solid Face on the dialog, select the other face. (Zoom if needed.) The direction vectors must point in roughly the same direction, either both up, or both down.

Choose OK twice. If the direction vectors are correct, choose OK.

Using Faces as Section Strings Specifying Interpolation, Alignment, and Scaling, and a Spine String The Interpolation Methods dialog displays. Choose OK to accept the default Linear interpolation method.

1460 The Swept dialog displays alignment methods and a tolerance. Use the Parameter alignment, and a tolerance of 0.001. Choose OK. The scale methods dialog displays. Choose Scale Laterally as the scaling method. The dialog of spine selection options displays. In this part file, the spine curve extends beyond both faces, so it will not limit the extents of the body. Select the spine string, and OK the selection.

Using Faces as Section Strings Completing the Model The dialog of Boolean operations display, because two other solids exist in the part file. Choose Create on the dialog of boolean operations. Shade the model.

Cancel all dialogs.

1461 Close all part files.

Using an Area Law to Control the Shape of a Swept Feature In this activity, you will create a body that has a constant area throughout its length by using a law curve. Then you will hollow the body. Finally, you will change the law curve and update the model.

Using an Area Law to Control the Shape of a Swept Feature Opening the Part Open the part file fff_swept_law.prt from the fff subdirectory, and start the Modeling application.

1462

Before you create this swept feature, you must find the area of that will govern the section.

Using an Area Law to Control the Shape of a Swept Feature Locating the WCS First, you need to use a WCS located on the plane of the governing area. Choose WCS

Orient.

The CSYS Constructor dialog displays. You need to specify the desired location. You will be finding the area of the closed curves near the lower left area on your screen. Choose CSYS of Object

on the dialog.

You must select the arc that you want the WCS oriented to.

1463 Select this arc and choose OK on the CSYS Constructor.

The WCS should be oriented at the corner of the arc you selected.

Using an Area Law to Control the Shape of a Swept Feature Finding the Area of the Governing Section The first section will govern the shape and area, but subsequent sections only approximate the shape to be developed.

Choose Analysis Area using Curves, because you will be selecting the governing curves to determine the area within the curves.

1464 The Analysis dialog displays. Choose Boundary (Temporary) as the boundary creation, because you do not want to create a permanent boundary here. The 2D Analysis dialog displays. Choose Chaining, and click on the yellow curve and choose OK twice. A dialog displays the default tolerance value. Choose OK to accept the tolerance default value (0.0100). The curves are selected. Vectors display in the graphics area.

The next dialog displays options for 2D analysis. Refer to the Unigraphics NX online help for more information about these options. Choose Perimeter/Area option.

Using an Area Law to Control the Shape of a Swept Feature Copying and Pasting Data to the Clipboard A dialog displays the perimeter of 11.1415 and area of 7.7853 for the governing area/shape that you selected.

1465 You need to copy the Area information onto your clipboard. Highlight the Area field. Press MB3 and choose Copy from the list. This copies and places the value in your clipboard. Cancel the dialogs. Toggle off the User Interface Preference for Tracking before you continue. (This will make editing the curve endpoint easier for this activity.)

Using an Area Law to Control the Shape of a Swept Feature Returning the WCS to Absolute An area law curve must be created relative to Absolute Zero in the Absolute X-Y plane. You need to return the WCS to Absolute. Choose WCS

Orient.

Choose the Absolute CSYS icon

and choose OK on the CSYS Constructor dialog.

Refresh the view. Cancel all dialogs.

Using an Area Law to Control the Shape of a Swept Feature Creating a Linear Area Law Curve Now, you will create a constant law curve that will control the area (law) at any cross-section along the swept feature. (You will use the Basic Curves icon to create the curve to do this.)

Choose the Basic Curves icon

or Insert

Curve

Basic Curves.

You will create a horizontal line 4 inches long that will start at XC = 0 and end at YC = the area value. Choose the Line icon. Choose the Point Method

Point Constructor option.

1466 The Point Constructor dialog displays. Choose Reset to make sure all XC, YC, and ZC values are set to zero. Remember, you still have the area value in your clipboard. Highlight the YC field, press MB3, and choose Paste. Your Base Point field values should look like this.

Choose OK on the Point Constructor to accept the base point values. An asterisk displays the first endpoint location for the horizontal line. Now, you will create the other endpoint for the law curve (line).

1467 You will want a constant (level) law, so any length horizontal line will work. You can, for example, use X = 4 but a longer or shorter line would also work. Change the XC field value to 4.0 and choose OK to create the line endpoint. The constant area law that you created will maintain the constant area at 7.7853, the area value that you found. Cancel the dialog. Your part should look like the figure below.

Using an Area Law to Control the Shape of a Swept Feature Creating the Swept Body Using the Area Law Curve for Scaling Now that you have created the law curve, you are ready to use it in a swept feature.

Choose the Swept icon

or Insert

Free Form Feature

Swept.

You need to select the guide string. Select the five curves in the cyan guide string, starting at the left end of the string, and choose OK twice.

1468

Using an Area Law to Control the Shape of a Swept Feature Specifying the First Section String The section string curves in this part file were created so that all sections could start at a midplane of each section. The side curves of the two rectangularly shaped strings were split into a magenta and a yellow curve so that this could be accomplished. The yellow curve needs to be the start of the section string, and the direction needs to point from the midplane location towards the remainder of the string. Also, remember that the vectors must point in a direction that will result in a non-twisted part. You need to select the first section string. You will use the set of curves at the left as the first section string. Start by selecting this end of the line first.

Then select the remaining magenta curves in a counter clockwise direction so that the arrow points upward, and choose OK.

1469

Using an Area Law to Control the Shape of a Swept Feature Selecting the Second Section String Next, you need to select the middle section string. You need to select the yellow curve, near the end that is in the middle of the string, and then select the remaining curves in a clockwise direction. Zoom in on the middle section string. Select the yellow curve near the end that is roughly in the middle of the straight section. Select in a clockwise direction, the curves in the second string, and choose OK. Again, check the vector, which should look like this.

Using an Area Law to Control the Shape of a Swept Feature Selecting the Last Section String You can continue to select the last curve in this section string. Select the yellow curve in the circular section string. Select the magenta curve in the third section string, and choose OK. (Again, check the vector.) The vectors should look like this.

1470

Choose OK, because no other section strings will be used.

Using an Area Law to Control the Shape of a Swept Feature Specifying Interpolation, Alignment, Tolerance, and Orientation You need to specify an interpolation method: Linear or Cubic. Choose the Linear interpolation option. Choose OK on the next dialog to accept the defaults of Parameter alignment and a .001 tolerance. You need to specify an orientation method. Choose the Fixed orientation. Using an Area Law to Control the Shape of a Swept Feature Specifying Scaling

Because you used only one guide string, you need to specify a scaling method. On the dialog that displays, you can select Area Law as the scaling method. Remember, you created a law curve (line) that you will use to control the area along the swept feature. Choose Area Law as the scaling method. You can specify the curve or other law methods in the dialog. Choose By Law Curve.

1471 Your law curve consists of one straight line, but you can choose other options to specify an area law, if you needed. Select the area law curve (line) that you created, and choose OK. You are prompted for a base line, which you will not need. Choose OK. Regenerate the view. The swept body is created. It is associated to the law curve as well as the guide and section strings.

Shade the model to look at it, then return to a wireframe view. Cancel all dialogs. You can check the ending Area to confirm accuracy in your part by using the following sequence: Analysis Area using Faces, use a Parameter value of 1, to give you the maximum accuracy possible, select the round planar face, and confirm the selection. You can also check the area of the face at the other end of the swept body, and compare these two areas. Because of the tolerance used (.001), the end area may vary slightly because the system can use the tolerance on each curve on the string. Your end area should be within .002 of the start area.

1472

Using an Area Law to Control the Shape of a Swept Feature Hollowing the Swept Solid Body Hollow the body with a -0.1 (negative) thickness and select the planar faces to be pierced. (Hint: Choose Insert Feature Operation Hollow, use a Default Thickness of -0.10, and select the two end faces of the swept body, and choose Apply.) Cancel the dialog. Make your hidden edges invisible. The model is complete.

Using an Area Law to Control the Shape of a Swept Feature Changing the Law Curve and Updating the Model If you change the law curve, the model will change. You will increase the area of the circular end of the model.

Choose the Edit Curve Parameters icon

or Edit

Curve

Parameters.

The Edit Curve Parameters dialog displays. At the bottom of the graphics area, you will see the XC, YC, and ZC fields, which will be set to zero at the time you select the Edit Curve icon. You will change the line endpoint using the fields at the bottom of the screen.

1473 Select the right endpoint of the law curve.

Because you toggled off the Tracking option, the values in the fields, below the graphics area, do not change as you move the cursor in the view. However, as you move your cursor, the white rubber banding is displayed showing you how the line might be positioned. Highlight the XC field. Key in 4 as the XC value. Tab to the YC field. Key in 2* and then press MB3 and Paste to paste in the value from your clipboard (7.785398), and press the Enter key on your keyboard.

Using an Area Law to Control the Shape of a Swept Feature Updating the Model You can choose the Update option on the Edit Curve Parameters dialog, or simply cancel the dialog to update the model. Cancel the Edit Curve Parameters dialog. The body updates to show the changed shape.

1474 You used a linear law curve, but area laws can be linear or curvilinear. Close all part files.

Using Fixed or ZC Axis Orientation In this activity, you will create compression springs made of square wire by using a guide and section string. One will have a fixed orientation, and the other will have a +ZC axis orientation.

Orientation Options

The orientation control of the section string as it moves along the guide is of primary importance in defining the proper shape.

1475 When you use only one guide string, you can specify how the section string is scaled and oriented as it moves down the guide. We recommend that you not use the Fixed option when you use only one guide string. The Face Normals option causes the section string to maintain a consistent relationship to the base face. The Vector Direction option causes the second axis of the local coordinate system to be aligned with a vector that you specify over the length of the guide string. You must define this vector so that it never becomes tangent to the guide string. If it does, the resultant feature could be poorly defined. The Forced Direction option lets you fix the orientation of the section plane with a vector as the section string is swept along the guide string. The section string slides along the guide string in a set of parallel planes. This option prevents self-intersections when the guide string has a tight curvature radius. Both the Forced Direction and Vector Direction options let you alter the swept surface. You would select a relative datum axis as the defining vector. Any changes that you make to the datum axis will be reflected in the swept surface. The Another Curve option lets you use another curve or solid edge to control section string orientation. This second curve must not intersect the guide, since this would make the second axis indeterminate. The A Point is similar to using another curve. You can use this option when constructing a three-sided swept feature, where one end of the section string is held in a fixed position and the other end slides along the guide. The Angular Law option lets you use the Law Subfunction dialog to define a law that will control the orientation.

Using Fixed or ZC Axis Orientation Opening the Part Open part file fff_swept_helix.prt from the fff subdirectory, and start the Modeling application.

1476

Choose the Swept icon

or Insert

Free Form Feature

Swept.

Using Fixed or ZC Axis Orientation Selecting a Guide and Section String You need to specify the guide strings. Select all five of the curves in the helical string for the guide string.

Choose OK twice. You need to specify the section strings. Select the four curves in square section string. (Zoom in if needed.) Choose OK twice.

1477

Using Fixed or ZC Axis Orientation Specifying Alignment, Tolerance, and Orientation Use the Parameter alignment. A tolerance of zero will keep the corners square. Change the Tolerance value to 0.0. Choose OK. Choose the Fixed orientation and Constant Scale of 1. Choose Create to create the spring. Cancel the dialog and Shade the model. Notice that the square shape twists as it moves along the helical guide.

This is probably not the type of spring that you would want.

1478

Using Fixed or ZC Axis Orientation Creating another Spring with a Vector Direction Orientation Next, you will orient the model along a vector direction. Another set of curves exists on layer 4. Make layer 4 selectable, and fit the view. Choose the Swept icon

or Insert

Free Form Feature

Swept.

To create the spring without twisting, you will use Vector Direction and use the +ZC direction. You need to specify the guide strings. Select all five of the curves in the helical string for the guide string on the right side of the graphics window. Choose OK twice.

Using Fixed or ZC Axis Orientation Selecting the Section String You need to specify the section strings. Select the four curves in the square section string. (Zoom in if needed.) Choose OK twice.

1479

Use the Parameter alignment. The tolerance of zero will keep the corners square. Change the Tolerance value to 0 and choose OK.

Using Fixed or ZC Axis Orientation Using a ZC Direction for the Orientation Choose Vector Direction for the orientation method. The Vector Constructor dialog displays. Choose ZC Axis for the orientation vector and OK the Vector Constructor dialog. Choose Constant as the scaling method. Choose OK on the dialog to accept the default scale value of 1. Choose Create to create the spring. Cancel the dialog. The two springs you created are shown below.

1480 Close all part files.

N-Sided This lesson covers the N-Sided Surface feature. This function lets you create a surface by selecting a closed set of curves or edges. The N-Sided surface smoothly patches gaps between surfaces without having to remove trim or change edges.

Shape control options let you control the sharpness of the center point of the new feature, while maintaining continuity constraints. The feature is useful for designer, stylists, and product designers who want to smoothly patch gaps between surfaces without having to untrim or change edges of the outside surfaces.

Creating an N-Sided Surface from a Closed Spline

1481

In this activity, you will create an N-Sided Surface and trim the surface to the closed loop. The image below is one made with the Analysis Face Radius function.

Creating an N-Sided Surface from a Closed Spline Opening the Part Open part file fff_n_side_loop_1.prt from the fff subdirectory, and start the Modeling application.. The part file contains a single closed spline with a degree of three and eight poles.

Creating an N-Sided Surface from a Closed Spline Starting the Feature For easier visibility as you work, you can change the grid line display. Change U Count to 10 and the V Count to 10 on the Modeling Preferences dialog.

1482 The design intent requires that a rounded and raised surface be created, using only the closed spine string in the view. The easiest way to create the surface is with the N-Sided Surface option.

Choose the N-Sided Surface icon Sided Surface.

or choose Insert

Free Form Feature

N-

The N-Sided Surface dialog displays.

Creating an N-Sided Surface from a Closed Spline Using the Trimmed Single Sheet Type Types of N-sided features include: Trimmed Single Sheet lets you create a single surface covering the entire region within a closed loop of selected surfaces. Multiple Triangular Patches lets you create a surface of individual, triangular patches, each consisting of the triangular region between each side and a common center point. The trimmed single sheet option will build a single face covering the entire region of selected N-sided loop, meeting with the loop within tolerance. The resulting surface will be trimmed by the N-Sided loop.

1483

Use the Trimmed Single Sheet type icon.

Creating an N-Sided Surface from a Closed Spline Selecting a Boundary

The Boundary Curves icon lets you select a closed loop of curves, edges, or sketch to serve as a boundary for the new surface. You need to select the profile curve(s) or edge(s) first. The profile must form a simple closed loop. It defines the boundary of the surface. You can also select the faces for the tangency or curvature constraints, if needed. For this activity there are no tangent faces. You can optionally select a spine curve or vector direction for U/V orientation of N-Sided sheet, but it is not needed for this activity. The Filter options let you select a curve, edge, sketch, or string. With the Boundary Curves icon

active, select the closed green spline.

The Boundary Faces icon lets you select faces for tangency and curvature constraints. You can match the position, tangency, and curvature of the N-Sided surface with the selected boundary faces. You do not need to specify Boundary Faces in this activity.

, because there are no boundary faces

Creating an N-Sided Surface from a Closed Spline Specifying the UV Orientation Because you need the curvature of the surface to be controlled along the YC axis for this model, you can use a vector orientation.

UV Orientation Options for an N-Sided Surface

The UV Orientation option lets you control the orientation by selecting a spine or by specifying a vector.

1484 The Spine option lets you specify a spine string to control the V orientation of the new surface. The U directional isoparametric lines of the new surface is oriented perpendicular to the selected spine curve.

The Vector selection step icon lets you define a vector to control the V orientation of the new surface. The UV orientation of the new N-Sided surface follows the given vector direction. Toggle on the Vector UV Orientation option. Choose the UV Orientation - Vector

icon.

The Vector Method options are now active on the N-Sided Surface dialog. You will use the ZC direction as the orientation. Choose the ZC Axis from the Vector Method options. The vector displays along the positive ZC direction of the coordinate system.

Creating an N-Sided Surface from a Closed Spline Trimming the Sheet Body The Trim to Boundary option, when toggled on, results in the sheet body being trimmed to the specified boundary curve. In this model, it is the closed spline curve. You need a trimmed surface for this model. Make sure that Trim to Boundary is toggled on. Choose Apply to complete the temporary creation of the sheet body.

1485 A sheet body is temporarily created, but has not been trimmed yet, because you have the option to use shape controls to model the surface.

Creating an N-Sided Surface from a Closed Spline Changing the Shape of the Surface and Completing the Trim The Shape Control dialog displays and lets you modify the shape of the sheet body. You will use the Shape Control options to create a domed surface. Notice that the surface passes through the three dimensional closed spline curve that you selected as the boundary curve.

You can dynamically control the shape of this sheet body by using the Center Flat slider bar on the dialog.

1486 Move the Center Flat slider bar on the Shape Control dialog to modify the shape of the NSided Surface feature. A Reset option lets reset the sheet to it's original form. Using the Center Flat slider, you could distort the sheet to look like this.

When you have adjusted the slider and developed a desired shape, choose OK on the Shape Control dialog. The sheet is trimmed to the boundary spine curve. Shade and Rotate the surface to look at the shape. Your model may look different, depending on your settings on your slider bars. As you rotate the model, notice the shape of the surface. When you edit an existing N-sided feature, you can specify a Distance & Angle tolerance, instead of using the default modeling tolerance used when creating the feature; and, you can use a Drag option that brings up Shape control dialog. Close all part files.

Multiple Triangular Patch N-Sided Surfaces

You will create a multiple triangular patch N-Sided surface.

1487

Multiple Triangular Patch N-Sided Surfaces Starting the Model Open part file fff_n_side_mesh_1.prt from the fff subdirectory, and start the Modeling application.

Multiple Triangular Patch N-Sided Surfaces Using Multiple Triangular Patches and Selecting the Boundary

Choose the N-Sided Surface icon Sided Surface.

or choose Insert

Free Form Feature

N-

1488 In this model, you need to create a rounded top to the six sided model. You need to maintain tangency to the six faces, when you create the patch. The Multiple Triangular Patch of triangular patches.

option lets you build a surface with a multiple number

Choose the Multiple Triangular Patches. Next, you need to select the profile (boundary) curve(s) or edge(s) for the patch. Set the Filter option to Edge since you will be limiting your selection to edges. The boundary can be any number of curves or edges that form a simple closed loop. Adjacent curves or edges don't need to be tangent or curvature continuous. With the Boundary Curves face.

toggled on, select the six edges of the smaller hexagonal

Multiple Triangular Patch N-Sided Surfaces Selecting Boundary Faces Next, you need to select the faces for the tangency or curvature constraints. Using tangent boundary faces is optional. Choose the Boundary Faces icon face.

and select the six faces adjacent to the hexagonal

1489

You do not need to merge the faces of the model. Check that Merge Faces if Possible is toggled off. Choose Apply.

Multiple Triangular Patch N-Sided Surfaces Controlling Flow Direction and Continuity The surface feature is temporarily created. The shape may not be what you desire, so you have the options on the Shape Control dialog to modify the patch. Near the bottom of the dialog, there are four Flow Direction on Outside Wall options:

Flow Direction and Outside Wall Options

Not Specified - the UV parameterization of the resulting sheet is equidistant towards the center point. Perpendicular - the V direction isoparametric lines of the resulting surface start from the outside edge in the direction perpendicular to the edge. The option is available if all the curves or edges in the loop are at least tangent continuous. ISO U/V Line - V directional isoparametric lines of the resulting surface will start from the outside edge in the direction following the U/V direction of outside face. It is only available when boundary constraints are tangent or curvature and faces are selected. Adjacent Edges - V directional isoparametric lines of the resulting surface will be following the side edges of constraining faces.

1490 Because you need to follow the flow based on the adjacent edges (boundary) that you selected, you need to use the Adjacent Edges option. Set the Flow Direction on Outside Wall to read Adjacent Edges. There are three Match Continuity options: Position, Tangency, and Curvature.

Match Continuity Options

Position connects the profile curves and the surface with continuity based on the position only. Outside boundary constraints are ignored. Tangency connects the profile curves of the surface with continuity based on tangency to the bounding surfaces. Curvature connects the profile curves of the surface with continuity based on continuing the curvature of the bounding surfaces. This is only available for multiple triangular patches. For this model, you will want the patch tangent to the outside faces. Experiment with each of the options for Match Continuity and notice the change of the shape, but finally set it to G1.

Multiple Triangular Patch N-Sided Surfaces Using Other Shape Control Options You can control the shape more completely with the Center Control option, the X, Y, Z, and the Center Flat sliders in the middle of the dialog.

1491

This course does not cover these options in detail, so refer to the Unigraphics NX online documentation for more details about the options. As you change the shape of N-sided surface while using multiple triangular patch method, changes to X, Y, Z, and Center Flat settings will be dynamically reflected to the displayed surface for visual feedback. These values will be remembered as a feature parameter. The Reset option will return the model to the original shape. Move the various sliders to see how the shape can be modified. Shade and rotate the model to view the changes. Choose OK to complete the model. The feature is created but not united to the solid body.

1492

Cancel all dialogs, and Close all part files.

N-Sided Surface from a Closed Planar String of Curves In this activity, you will create an N-Sided surface using the string of closed planar curves.

N-Sided Surface from a Closed Planar String of Curves Starting the Model Open the part file fff_n_sided.prt from the fff subdirectory, and start the Modeling application.

1493

Choose the N-Sided Surface icon Surface.

or choose Insert

Free form Feature

N-Sided

The N-Sided Surface dialog displays.

N-Sided Surface from a Closed Planar String of Curves Using Multiple Triangular Patches and Boundary Curves The Multiple Triangular Patches option creates a set of triangular faces that merge at a center point, which you have control over. Choose Multiple Triangular Patches. You need to specify the boundary curves for the surface. Choose the Boundary Curves

selection step.

Set the Filter to Curve. Select all eight curves. Toggle on the Merge Faces if Possible option. If this is left off, the system will create one face for each selected curve. Choose Apply on the dialog. A temporary grid display of the surface displays.

1494

N-Sided Surface from a Closed Planar String of Curves Using the Shape Control Options The Shape Control dialog also becomes available, so that you can modify the shape of the surface, which currently appears flat. To control the drag along the ZC axis, leave the Center Control set to Position and use the Z slider bar to adjust the height or depth of the curved surface. Set the Center Control to Position. Now, drag the Z scroll bar back and forth to see what it does, and leave the model with the surface curved upwards along the ZC axis. Many other controls are available to change the shape of the N-Sided surface. Drag the other scroll bars to see what they do. Change the Center Control to Tilting and try the available scroll bars. Choose Reset at the bottom of the dialog to return the surface to a flattened surface. With Center Control set to Position, drag Z to about this shape again. (Make sure that X and Y sliders are set to 50 and that Center Flat is set to 100.)

N-Sided Surface from a Closed Planar String of Curves Using Flow Direction on Outside Wall

You can change the flow direction on the outside walls. Four options are available: Not Specified, Perpendicular, Iso U/V Line, and Adjacent Edges. Set the Flow Direction on Outside Wall to Perpendicular. Notice the differences on the surface.

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Set the Flow Direction on Outside Wall back to Not Specified. OK the dialog to complete the shape change. Unless you shade the view, you don't see the shape of the surface. Shade and Rotate the view to see the final shape of the N-Sided surface.

Restore the view and return it to a wireframe display. Close all part files.

Trimming an N-Sided Surface from a String of Closed Planar Curves In this activity, you will create an N-Sided surface using the string of closed planar curves, and using the Trimmed Single Sheet options. You will trim the shape to the boundary curves used to generate the surface. The surface U/V vector orientation will be along the XC axis.

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Trimming an N-Sided Surface from a String of Closed Planar Curves Starting the Model Open the part file fff_n_sided.prt from the fff subdirectory and start the Modeling application.

Choose the N-Sided Surface icon Surface.

or choose Insert

Free form Feature

N-Sided

Trimming an N-Sided Surface from a String of Closed Planar Curves Specifying the Type and Boundary Curves The Trimmed Single Sheet type creates a single face sheet that you can have trimmed to the bounding objects or not. Choose the Trimmed Single Sheet Type. You need to select the boundary curves for the N-Sided surface. With the Boundary Curves eight curves.

selection step active, and Filter set to Curve, select the

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Trimming an N-Sided Surface from a String of Closed Planar Curves Specifying Orientation You need to choose the UV orientation. Set the UV Orientation options to Vector. When the Trim to Boundary is toggled on the system will trim the final surface. Toggle on the Trim to Boundary option. You need to use the UV Orientation to Vector selection step to define the vector method that you want to use. Choose the UV Orientation to Vector

selection step.

Set the Vector Method to XC Axis. A direction vector displays along XC.

Choose Apply on the N-Sided Surface dialog to obtain a temporary untrimmed sheet.

Trimming an N-Sided Surface from a String of Closed Planar Curves Using Shape Control The untrimmed surface temporarily displays.

The Shape Control dialog also displays.

1498 Move the Center Flat scroll bar, and leave the model in about this shape.

Choose OK on the Shape Control dialog to complete the surface. To see the surface more easily, shade and rotate it. Notice that the shape is different than when you created the N-Sided surface using the multiple triangular patches option.

Close all part files.

Multiple Triangular Faces, Using a Boundary Face, and Boundary Edge In this activity, you need to fill in the inner area with a surface that is indented, and then transform curves to modify the sheet body.

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Multiple Triangular Faces, Using a Boundary Face, and Boundary Edge Starting the Model Open the part file fff_n_sided_1.prt from the fff subdirectory and start the Modeling application.

Choose the N-Sided Surface icon Surface.

or choose Insert

Free form Feature

N-Sided

The N-Sided Surface dialog displays. In this activity, you need to create a surface that fills in the center of this part, and the surface must be curvature continuous with the existing surface. Choose the Multiple Triangular Faces Type. Toggle on the Merge Faces if Possible option.

Multiple Triangular Faces, Using a Boundary Face, and Boundary Edge Selecting Boundary Curves and Faces You need to use the inner edge of the sheet body for the boundary curves, and the existing sheet for the boundary face. With the Boundary Curves selection step active, and the Filter set to Edge, select the interior edge of the existing surface.

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Choose the Boundary Faces

selection step.

Select the existing surface.

Multiple Triangular Faces, Using a Boundary Face, and Boundary Edge Shaping the Surface OK the N-Sided Surface dialog. The surface is temporarily created.

The Shape Control dialog displays to let you modify the surface. To create an indent that is centered along the ZC axis, you'll need to set the Center Control to Position, and the ZC Axis slider to a value smaller than 50. Change the Z slider bar so that model looks like this.

1501 The indented N-Sided surface is temporarily modified. Choose OK on the Shape Control dialog. The model is complete. Shade the model for a better view.

Return to a wireframe display mode.

Multiple Triangular Faces, Using a Boundary Face, and Boundary Edge Editing the Ruled Surface and Updating the Model

You are now going to edit the ZC location of the outer curves that were used to create the original ruled surface, and see what it does to the N-Sided surface you just created. Make layer 42 Selectable, and layer 82 Invisible.

Choose Edit

Transform.

The Transform dialog displays, which looks a lot like the Class Selection dialog. You will transform all of the curves along the ZC axis and notice the change in the model. Select all the outer curves that formed the ruled sheet body.

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Choose OK on the Transform dialog. Now, you need to choose how you want the curves transformed. A list of twelve options displays. (Details on all options are available in the Unigraphics NX online help.) Choose Translate. Two translate options are available, but you need to translate along ZC by five units. Choose Delta. The system lets you specify a delta in X, Y, and Z for the curves. You only need to translate along Z. Enter a DZC value of 5 and choose OK on the dialog of translation values. Make layer 82 selectable. Now, you are provided with additional translation options. You need to move the curves. Choose Move and allow the N-Sided surface to update. Shade the model. Choose Move 3 more times. Rotate the model to notice the changes. Notice how the N-Sided Surface updates its shape each time. Close all part files.

1503

Section This lesson covers using the Section Body to construct bodies through cross sections that you define using conic, cubic, and quintic construction techniques.

To comply with industry standards, and to make data transfer easy, the Section option produces a body with B-Surfaces as output. You can think of a section feature as an infinite family of section curves lying in prescribed planes, starting and ending on, and passing through, certain selected control curves. A typical application for sections would be in the design of an aircraft fuselage, or auto body panel.

Creating the Ends-Apex-Shoulder Section Feature In this activity, you will create an ends-apex-shoulder Section feature. You will create it through two ends and use an apex and shoulder to define the feature.

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Creating the Ends-Apex-Shoulder Section Feature Opening the Part Open the part file fff_ends_apex_shoulder.prt from the fff subdirectory, and start the Modeling application. The part file contains curves and sheet bodies.

Creating the Ends-Apex-Shoulder Section Feature Starting the Feature

Choose the Section Body icon

or Insert

Free Form Feature

Section.

A Section dialog displays. The top half of the Section dialog contains 20 section feature types (icons). The lower half of the dialog contains options to control the section type, fitting type, and apex creation.

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Before you choose a section feature type, you need to specify the Section Type (cross section shape in the U direction), the Fitting Type (cross section type in the V direction), and whether you want the system to create an apex curve for you.

Creating the Ends-Apex-Shoulder Section Feature Specifying the Section and Fitting Type The Section Type controls the shape of the sections in the U direction (i.e., perpendicular to the spine string).

Section Types - (U-Direction)

Conic - since rational B-spline curves can represent conic curves exactly, this option produces a true, exact conic shape with no reversals in curvature. Parameterization may be highly non-uniform. Rho values between 0.0001 and 0.9999 are allowed. Cubic - the curves have roughly the same shape as their rational counterparts (used in the Conic option) but produce a surface with a better parameterization. This option distributes the flow lines along the entire curve, but does not produce exact conic shapes. For example, rho values greater than 0.75 create section curves which are not shaped like a conic. For this reason, the maximum rho allowed when creating polynomial cubic sections is 0.75.

1506 Quintic - the surfaces are degree 5, and are C2 (curvature continuous) between patches.

For this activity (creation of a ends-apex-shoulder section feature), you will produce an exact conic shaped sheet in the U direction. Use the Conic section type. The Fitting Type controls the degree and shape of the feature in the V direction (i.e., parallel to the spine string).

Fitting Types - (V-Direction)

Cubic - yields degree 3 and is C1 (tangent continuous) between patches. Quintic - yields degree 5 and is C2 (curvature continuous) between patches.

For this activity (creation of a ends-apex-shoulder section feature), you will produce a sheet with a degree of 3 in the V direction. Use the Cubic fitting type. If you needed to create an apex curve, you would toggle the Create Apex Curve option on. For this part, you will not have to create an apex curve. Now, you are ready to select the type of section feature (icon) that you want to create.

Creating the Ends-Apex-Shoulder Section Feature Using Ends-Apex-Shoulder

The ends-apex-shoulder section feature begins on the specified start edge string, passes through an interior string known as the shoulder, and stops on the end edge string. The slope at each end is defined by a selected apex string.

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You will use the ends-apex-shoulder icon to create a section feature that is tangent to both sheets.

Choose ends-apex-shoulder icon.

Creating the Ends-Apex-Shoulder Section Feature Specifying the Starting Edge and Shoulder String The dialog lists string selection options. You need to select the starting edge. You can select solid faces, solid edges, and curves for the strings. The curves located on the upper edges of the sheets will be used as the start and end edges of the section. Select the start edge string and choose OK.

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Select the shoulder string and choose OK.

Creating the Ends-Apex-Shoulder Section Feature Specifying the Ending Edge and Apex

A dialog of string selection options continues to display. You need to select the end edge string. Select the end edge string and choose OK.

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You will use the existing line for the apex. It is positioned at the location of the intersection of the two sheets (if they were extended to an intersection point). Select the apex string and choose OK.

Creating the Ends-Apex-Shoulder Section Feature Specifying the Spine String A dialog of string selection options displays again. You need to select a spine string.

Using a Spine String

A spine should be smooth and not complex, as the complexity of the body will be reflected by the complexity of the spine. At each point on the spine, the system constructs a section plane that is perpendicular to the spine string, tangent at the point in question. Then the system

1510 intersects the plane with each control string, obtaining a collection of points and slope control vectors to construct conic section curves. For section features, the spine string must be approximately parallel with the starting and ending strings. Below, the section sheet was created using the ends-slopes-rho method. Three section strings were used, as well as a spine curve. The points shown (P?, P?, P?) were obtained by intersecting these strings with a section plane. The three points together with a rho value define a conic section curve.

Unlike the other strings, the spine string selection is directionally sensitive. The end you select becomes the start direction of the spine and thus determines the directional sense of the body. This is very important to know when you are constructing a body with different starting and ending rho values.

Select the apex as the spine string and choose OK.

The sheet body is created. It passes through edges and the specified shoulder string.

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Cancel all dialogs. Close all part files.

Creating an Ends-Apex-Rho Section Feature with a Constant Rho In this activity, you will create these two ends-apex-rho

Section features.

Creating an Ends-Apex-Rho Section Feature with a Constant Rho Opening the Part Open part file fff_ends_apex_rho.prt from the fff subdirectory, and start the Modeling

1512 application. The part has two sheet bodies and one curve.

Creating an Ends-Apex-Rho Section Feature with a Constant Rho Selecting a Section Type Choose the Section Body icon

or Insert

Free Form Feature

Section.

For this activity, you will use a Conic section type.

Comparison of Conic and Cubic Section Types

Notice the difference in the shape of the flow lines between the Conic and Cubic section types shown below. Below, both features were created from the same geometry, using the ends-apex-rho creation method, with the rho value determined by cubic blend and varying from 0.3 to 0.7. The distance tolerance was set to .001.

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Use the Conic section type.

Creating an Ends-Apex-Rho Section Feature with a Constant Rho Starting the Ends-Apex-Rho Feature

The ends-apex-rho section feature starts on an edge string and ends on an edge string (like all three ends-apex options). The slope at each end is defined by an apex string. The fullness of the section is controlled by the rho scalar value(s). No shoulder string is used. These features are similar to the ends-apex-shoulder option, except a rho value is used instead of a shoulder string. Choose the ends-apex-rho icon. You will create these two ends-apex-rho section features.

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Creating an Ends-Apex-Rho Section Feature with a Constant Rho Specifying Edges, Apex, and Spine You must select a start edge string. Select the start edge string, and choose OK. Select the end edge string, and choose OK. Apex Strings and Tolerances for the Ends Apex Rho Feature

Apex Strings - The apex string is also referred to as the common slope control string or anchor string. The Create Apex Curve toggle lets you create an apex curve if one does not exist. You must input enough data to specify the five conditions required to define a section. Internally, the system represents the section in the simplest form possible, so if you specify two separate slope control strings (one for each edge), the system will compute and store a single apex curve that is the intersection of the tangents. When the system must compute the apex curve, you may create this curve along with the body. The resulting apex curve will often illustrate problems encountered when constructing a section body with separate slope controls, as it is not always easy to tell how two continuously changing slope controls will intersect. This section sheet was created using the ends-slopes-rho method. The Create Apex Curve toggle was on. Four control strings and a spine were selected. The system created the apex curve, and constructed it by intersecting tangents.

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The construction of the body involves an approximation process, which is controlled by the Modeling distance tolerance. Distance Tolerance - All techniques using approximation require a distance tolerance, the maximum allowable distance between the true theoretical sheet and the resulting sheet that the system creates to approximate it. Be sure to use a realistic tolerance value. If the input value is too small, the resulting body will contain many more patches than is necessary, or worse, the system may not be able to construct a body.

Select the apex string and choose OK. Select the same string as the spine string and choose OK.

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Creating an Ends-Apex-Rho Section Feature with a Constant Rho Specifying a Constant Rho Now, you need to select one of the rho options: Constant, Least Tension, and General. You will be creating all types. You need to provide a rho definition. The Constant rho option maintains a constant rho value along the body.

Choose Constant option. The dialog displays a default rho value. For the Constant option, you can only enter a single rho value.

Rho Values for Ends Apex Rho Feature

Rho is a ratio of distances. A small rho value (near zero) produces a very flat section. A large rho value (near 1) produces a very pointed section. Rho must be 0.

This example of an ends-apex-rho section feature has a rho value of .8, so the cross sections of the feature are hyperbolas.

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Key in a rho value of .75 and choose OK. The section sheet is created. The shaded view looks like this.

Creating an Ends-Apex-Rho Section Feature with a Constant Rho Using a Smaller Rho Now, you will recreate the sheet with a smaller rho value, just to see how they differ. Choose the ends-apex-rho icon. Select the start edge string, end edge string, apex string, and apex again as a spine string.

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Choose the option of Constant rho. Key in a value of .5 and choose OK.

Cancel all dialogs. Close all part files.

Creating an Ends-Apex-Rho Section Feature with a General-Linear Rho In this activity, you will create two general Section features using the ends-apex-rho option. The first one will have a linear rho.

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The second will have a cubic rho.

Creating an Ends-Apex-Rho Section Feature with a General-Linear Rho Opening the Part Open part file fff_ends_apex_rho_general.prt from the fff subdirectory, and start the Modeling application. This part contains constant ends-apex-rho sheets that are similar to the ones you created in the last activity.

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Make layer 30 the work layer and layer 20 invisible.

Creating an Ends-Apex-Rho Section Feature with a General-Linear Rho Starting the Feature

Choose the Section Body icon

or Insert

Free Form Feature

Use the Conic section type. Choose the ends-apex-rho icon. Select and OK the start edge, end edge, apex, and the spine string.

Section.

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Creating an Ends-Apex-Rho Section Feature with a General-Linear Rho Specifying a General Linear Rho The dialog of three rho options displays. You will use the General option, which lets you specify a law option. Choose General. Now, you can choose a law option from the law subfunction dialog that displays.

Law Subfunction Options

Constant lets you define a constant value along the entire law function. Linear lets you define a linear rate of change from a start point to an endpoint. Cubic lets you define a cubic rate of change from a start point to an endpoint. Values Along Spine - Linear and - Cubic lets you use two or more points along a spine to define either a linear or cubic law function. After selecting a spine curve, you can indicate multiple points along the spine. You are prompted to enter a value at each point. By Equation lets you define a law using an expression and a parameter expression variable. All variables must be previously defined within the Expression tool, and the expression must use the parameter expression variable. By Law Curve lets you select a string of tangent continuous curves to define a law function. After selecting the curves, a base line must be selected. The base line defines a vector direction for the orientation. A directional vector is displayed to indicate the base line direction. The direction can be reversed.

When you use the General, and Linear options, the rho value will be linearly tapered between the starting and ending values corresponding to the start and end of the body. You will be required to enter two values (beginning and ending values) for the linear rho section sheet.

1522 Choose Linear. The dialog displays default start and end values for the linear rho. Key in a rho Start Value of 0.4 and a rho End Value of 0.6. Choose OK. The sheet is created. The shaded view looks like this.

Creating an Ends-Apex-Rho Section Feature with a General-Linear Rho Specifying a General Cubic Rho Now, you will recreate the feature using a cubic rho. Make layer 40 the work layer and layer 30 invisible. Choose the ends-apex-rho icon. Select and OK the start edge, end edge, apex, and spine string.

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Creating an Ends-Apex-Rho Section Feature with a General-Linear Rho Specifying Rho Values The General - Cubic option causes the rho value to be cubically blended between starting and ending values corresponding to the start and end of the body.

Choose General. Choose Cubic. You will use two rho values. Use the default 0.4 and 0.6 values that you used for the linear rho feature, and choose OK. The shaded model looks like this.

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Make all layers selectable, and compare the different sheets created with the ends-apex-rho option. Close all part files.

Creating an Ends-Apex-Rho Section Feature with a Least Tension Rho In this activity, you will create this ends-apex-rho tension rho.

Section feature with a least

Creating an Ends-Apex-Rho Section Feature with a Least Tension Rho Opening the Part Open part file fff_ends_apex_rho_least.prt from the fff subdirectory, and start the

1525 Modeling application. This part contains four ends-apex-rho sheets that are similar to the ones you created in the last two activities.

Make layer 50 the work layer, and make layers 20, 30, and 40 invisible. (Layer 1, and 10 should be selectable.)

Creating an Ends-Apex-Rho Section Feature with a Least Tension Rho Starting the Feature

Choose the Section Body icon

or Insert

Free Form Feature

Use the Conic section type. Choose the ends-apex-rho icon. Select the start edge, end edge, apex, and the apex again as the spine.

Section.

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Creating an Ends-Apex-Rho Section Feature with a Least Tension Rho Using Least Tension for Rho Least Tension creates a feature with a rho value that is computed from the input geometry according to a least-tension condition. In most cases this produces an ellipse. When the angle between the chord and the tangent is the same at each end of the conic, the result is a circular arc.

Choose Least Tension and the section is created. The feature is created. The shaded view looks like this.

Cancel the dialog. Close all part files.

Creating a Fillet-Shoulder Section Feature In this activity, you will create a fillet-shoulder and has a defined shoulder like this one.

Section that is tangent to two faces

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Creating a Fillet-Shoulder Section Feature Opening the Part Open part file fff_fillet_shoulder.prt from the fff subdirectory, and start the Modeling application.

Creating a Fillet-Shoulder Section Feature Starting the Feature

Choose the Section Body icon

or Insert

Use the Conic section type. Create Apex Curve can be toggled off.

Free Form Feature

Section.

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The fillet-shoulder section feature is one with a smooth blend between two strings that lie respectively on two bodies. The fillet-shoulder section feature starts on the first string selected, is tangent to the first body selected, ends on the second string, is tangent to the second body, and passes through the shoulder string.

Choose the fillet-shoulder icon.

Creating a Fillet-Shoulder Section Feature Specifying Faces and Strings You need to select the first set of faces, and edge string. Multiple faces can be selected. Select the first face and choose OK. Select the top edge string on the first face as the first string and choose OK. You need to select the shoulder string. Select the shoulder string and choose OK.

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Select the second face and choose OK. Select the top edge curve as the string and choose OK. Select the spine.

Creating a Fillet-Shoulder Section Feature Completing the Feature Choose OK. The fillet-shoulder feature is created.

Cancel all dialogs. Close all part files.

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Creating an Ends-Slopes-Rho Section Feature with a Constant Rho In this activity, you will create an ends-slopes-rho ends, 2 slopes, and a rho value.

Section feature by using two

Creating an Ends-Slopes-Rho Section Feature with a Constant Rho Opening the Part Open part file fff_ends_slopes_rho.prt from the fff subdirectory, and start the Modeling application.

Creating an Ends-Slopes-Rho Section Feature with a Constant Rho Starting the Feature Choose the Section Body icon

or Insert

Free Form Feature

Section.

1531 Conic does not work for ends-slopes-rho section features. If you choose Conic when creating this section type, the system ignores your choice and uses Cubic instead. Use the Cubic section type. The ends-slopes-rho edge string.

section feature starts on the first edge string and ends on the second

Slope is defined at the start and end by two independent slope control strings. The fullness of each section is controlled by the corresponding rho value.

Choose the ends-slopes-rho icon.

Creating an Ends-Slopes-Rho Section Feature with a Constant Rho Selecting Strings You will not have to create an apex curve in this part. Select the start edge string and choose OK. Select the start slope control string and choose OK. Select the end edge string and choose OK. Select the end slope control string and choose OK. Select the spine string and choose OK.

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Creating an Ends-Slopes-Rho Section Feature with a Constant Rho Using a Constant Rho A dialog displays the rho options, which are the same options that you used when you created the ends-apex-rho section feature. The Constant rho option maintains a constant rho value along the body. You need to enter a single rho value. Choose Constant, and choose OK to accept the default of .5 as the rho value. The feature is created.

The Section dialog should be displayed with the ends-slopes-rho icon highlighted. Make layer 20 the work layer, and layer 10 invisible.

Creating an Ends-Slopes-Rho Section Feature with a Constant Rho Creating Another Feature

1533 This time, you will have the system create the apex curve when you create the feature. Toggle on the Create Apex Curve option. Choose the ends-slopes-rho icon. Select the strings as you are prompted.

Creating an Ends-Slopes-Rho Section Feature with a Constant Rho Using a General Linear Rho Use the General rho option. Choose Linear. Key in .25 as a start rho value, .6 as an end rho value, and choose OK to create the feature. Notice that an apex curve is created.

Blank the feature so that you can create one with cubic rho values.

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Creating an Ends-Slopes-Rho Section Feature with a Constant Rho Creating Another Feature

Choose the ends-slopes-rho icon. Select the strings as you are prompted.

Creating an Ends-Slopes-Rho Section Feature with a Constant Rho Using a General Cubic Rho Use a rho definition of General. Choose Cubic as the Law option, key in .25 as a start rho value, key in .6 as an end rho value, and choose OK. The feature is created.

Blank the feature so that you can create one with least tension rho values.

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Creating an Ends-Slopes-Rho Section Feature with a Constant Rho Creating Another Feature Choose the ends-slopes-rho icon. Select the strings as you are prompted.

Creating an Ends-Slopes-Rho Section Feature with a Constant Rho Using a Least Tension Rho When you are prompted for the rho, choose Least Tension, and cancel all dialogs. The feature is created. Evaluate all sheets.

Close all part files.

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Creating Five-Points Section Features In this activity, you will create two five-points and a spine curve for each feature.

Section features using five strings

Creating Five-Points Section Features Opening the Part Open part file fff_five_points.prt from the fff subdirectory, and start the Modeling application.

Make layer 10 the work layer.

Creating Five-Points Section Features Starting the Feature Choose the Section Body icon

or Insert

Free Form Feature

Section.

Use the Conic section type and Cubic fitting type. Check that Create Apex Curve is toggled off. The five-points

section feature uses five existing strings as control strings.

1537 The body starts on the first string, passes through three selected interior control strings, and ends on the fifth string. The five control strings must all be different, but the spine string can be a previously selected control string.

Choose the five-points icon.

Creating Five-Points Section Features Creating the First Sheet Select and OK the ends of each of the five cyan strings in this sequence.

Select and OK the spine string (dashed green line) and Cancel the dialog. The first sheet is created.

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Creating Five-Points Section Features Creating the Second Sheet Make layer 20 the work layer. Make layer 2 and 4 selectable, and other layers invisible. Create another five-points section feature by selecting the five yellow strings, and selecting the green dashed line as the spine string. The second feature is created.

Make layer 10 selectable. Make all other layers Invisible.

Close all part files.

Creating an Ends-Apex-Hilite Section Feature In this activity, you will create an ends-apex-hilite green.

Section feature shown below in

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Creating an Ends-Apex-Hilite Section Feature Opening the Part Open part file fff_ends_apex_hilite.prt from the fff subdirectory, and start the Modeling application. You will see a tube and a number of lines.

Rotate the view to see the clearance between the strings and the tubular feature. Then Restore the view, and Zoom in if necessary to read the names on the objects that you will be selecting next.

Creating an Ends-Apex-Hilite Section Feature Starting the Feature

1540

Choose the Section Body icon

or Insert

Free Form Feature

Section.

The ends-apex-hilite feature starts on the first string, ends on the second string, and is tangent to a specified string. The slope at each end is defined by a selected apex string. This option is useful where you want to control the tangency of the sheet to a specified pair of lines, or where you want to prevent interference of the section feature and another feature.

Choose the ends-apex-hilite icon.

Creating an Ends-Apex-Hilite Section Feature Selecting the Start and End Edge You need to select the starting edge string that will define the beginning of the section feature. Select the cyan string that is labeled START EDGE, and choose OK. You need to select the ending edge string that will define the end of the section feature. Select the green string labeled END EDGE and choose OK.

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Creating an Ends-Apex-Hilite Section Feature Selecting the Apex, and Hilite Start and End You need to select the apex string. The end edges and apex will control the end slopes. Select the cyan dashed string labeled APEX and choose OK. Now, you can select the highlight start string that defines where the tangency begins. Select the yellow string labeled HILITE START and choose OK. Now, you can select the ending location for the highlight that defines where the tangency stops. Select the yellow string labeled HILITE END and choose OK. Now, you can select a spine string. Select the green spine string labeled SPINE and choose OK. The section sheet is created. The section feature is associative with its defining data.

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Cancel the Section dialog. The system lets you edit parameters such as tolerance and rho value. Any time you create a section feature, the system will use the current distance tolerance for surface approximation. The tolerance is stored with the feature and becomes independent from the modeling tolerance setting. Shade and Rotate the model and notice the clearance between the two objects. Close all part files.

Creating an Ends-Slopes-Hilite Section Feature In this activity, you will create an ends-slopes-hilite green.

Section feature, shown in

1543

Creating an Ends-Slopes-Hilite Section Feature Opening the Part Open part file fff_ends_slopes_hilite.prt from the fff subdirectory, and start the Modeling application. Rotate the view to see the clearance between the strings and the tubular feature. Then restore the view, and zoom in if necessary to read the names on the objects that you will be selecting next.

Creating an Ends-Slopes-Hilite Section Feature Starting the Feature

1544

You will be creating a section feature that will clear the tubular feature.

Choose the Section Body icon

or Insert

Free Form Feature

Section.

The ends-slopes-hilite section feature starts on one edge string and ends on a second edge string and is tangent to a specified string. Slope is defined at the start and end by two independent slope control strings.

Choose the ends-slopes-hilite icon.

Creating an Ends-Slopes-Hilite Section Feature Selecting the Start and End for Edges and Slopes You must select a starting edge string. Select the cyan string labeled START EDGE and choose OK. Next, you must select a starting slope control string. Select the magenta string labeled START SLOPE and choose OK. Now, you need to specify an end edge string. Select the green string labeled END EDGE and choose OK. And now, you can select the ending slope control string.

1545 Select the magenta string labeled END SLOPE and choose OK.

Creating an Ends-Slopes-Hilite Section Feature Specifying Hilite Start and End You need a highlight start string. Select the yellow string labeled HILITE START and choose OK. You also need a highlight end string. Select the yellow string labeled HILITE END and choose OK.

Creating an Ends-Slopes-Hilite Section Feature Completing the Feature

1546 Finally, you need a spine string. Select the green string labeled SPINE and choose OK. The section feature is created.

Shade and rotate the model and notice the clearance between the two objects. Close all part files.

Creating a Fillet-Hilite Section Feature In this activity, you will create a fillet-hilite Section feature that has a smooth blend between two strings which lie respectively upon two bodies, and are tangent to a specified string.

1547

Creating a Fillet-Hilite Section Feature Opening the Part Open part file fff_fillet_hilite.prt from the fff subdirectory, and start the Modeling application. Review the labeled objects in this part.

Creating a Fillet-Hilite Section Feature Starting the Feature

Choose the Section Body icon

or Insert

Free Form Feature

Section.

1548 Create Apex Curve should be toggled off. Use Conic Section Type, and Cubic Fitting Type. The fillet-hilite

section feature passes through two points, and is tangent to three strings.

Choose the fillet-hilite icon.

Creating a Fillet-Hilite Section Feature Selecting the Start Face and Edge You need to specify a starting face and edge. You can select multiple faces on the bodies, but this part has only a single face. Select the magenta face labeled START FACE and choose OK.

You need to select the first string on the first set of faces. Select the upper edge string labeled START EDGE, and choose OK.

1549

Creating a Fillet-Hilite Section Feature Selecting the End Face and Edge You need to specify a second face. You can select multiple faces on the bodies, but this part has only a single end face. Select the magenta face labeled END FACE and choose OK. Now, you must select the second string that will have the tangent condition. Select the string of the end face labeled END EDGE, and choose OK.

Creating a Fillet-Hilite Section Feature Specifying the Hilite Start and End, and Spine As with other hilite options, you need to select the highlight starting string. Select the yellow string labeled HILITE START and choose OK. You also need to select the highlight ending string. Select the yellow string labeled HILITE END and choose OK.

1550

Creating a Fillet-Hilite Section Feature Completing the Feature You will need to use a spine string to control parameterization. Select the green string labeled SPINE as the spine string, and choose OK. The section feature is created. It is tangent to the two faces, and follows the highlight strings. This section feature has a smooth blend between two strings which lie respectively upon two bodies, and are tangent to a specified string.

Cancel the Section dialog. Shade and rotate the view to see clearances between the various bodies. Close all part files.

1551

Creating a Two-Points-Radius Section Feature In this activity, you will create a two-points-radius Section feature that bridges between the two existing sheets. The shaded view will look like this.

Creating a Two-Points-Radius Section Feature Opening the Part Open part file fff_two_points_radius.prt from the fff subdirectory, and start the Modeling application.

Change to a wireframe display.

Creating a Two-Points-Radius Section Feature Starting the Feature Choose the Section Body icon

or Insert

Free Form Feature

Section.

1552 Create Apex Curve can be toggled off. Use Conic Section Type and Cubic Fitting Type. The two-points-radius

section option creates circular sections of a specified radius.

Choose the two-points-radius icon.

Creating a Two-Points-Radius Section Feature Selecting the Start, End, and Spine You need to select the start edge string. Your order of selection is important, because the body is created in a counter?clockwise direction from the first selected edge curve to the second selected edge curve, with respect to the spine direction. Select the start edge, and choose OK. You need an end edge string. Select the end edge string, and choose OK. You need a spine string. Select the end edge as the spine string, and choose OK.

1553

Creating a Two-Points-Radius Section Feature Completing the Feature with a Constant Radius The Section Radius Data dialog displays a default radius, and an option The Use Radius Law option lets you specify a law to control the radius.

Any radius specified must be at least half the distance between the starting and ending edges of each section. The distance between the two sheet bodies is 100 millimeters, so you could use any value greater than 50. Key in 55 as the Radius value and choose OK. The shaded feature looks like this.

1554

You can change the starting, ending, or spine strings, change the radius method and value used, and change the section type or tolerance by editing the feature. Blank the section feature.

Creating a Two-Points-Radius Section Feature Starting Another Feature The Section dialog should still be displayed. This time, you will create the feature, using a radius law. Choose the two-points-radius icon. Select and OK the start edge, end edge, and spine string.

The Section Radius Data dialog displays. You will use the Use Radius Law option.

1555 Choose Use Radius Law on the Section Radius Data dialog. The dialog of law options displays. Choose the Linear law option. For linear laws you need to define two law values in the Law Controlled dialog that displays. Remember, the distance between the two sheet bodies is 100 millimeters, so you can use any value greater than 50. Key in a Start Value of 55 and an End Value of 150, and choose OK twice. The feature and an apex curve are created. Cancel all dialogs. Close all part files.

Creating a Fillet-Bridge Feature Using Match Tangents In this activity, you will create a fillet bridge Section feature and trim the body with the sheet to create a curved surface on the model.

Creating a Fillet-Bridge Feature Using Match Tangents Opening the Part Open part file fff_fillet_bridge_tangent.prt from the fff subdirectory, and start the

1556 Modeling application.

Creating a Fillet-Bridge Feature Using Match Tangents Starting the Feature Choose the Section Body icon

or choose Insert

Free Form Feature

Section.

Toggle off Create Apex Curve. For the fillet-bridge section feature, the Section Type choice is controlled by options on the dialog, so you do not have to change the Section Type or Fillet Type options. The fillet-bridge option creates a body with sections that form a bridge between two curves which lie on two sets of faces. You can choose to match tangents or curvatures at the ends of the fillet-bridge section, or you can choose a spline whose general shape will be reflected in the feature.

You need to have two faces with curve strings on each of the faces, and a spine string. Choose the fillet-bridge icon.

1557

Creating a Fillet-Bridge Feature Using Match Tangents Using Match Tangents A Bridge Section dialog of matching methods displays.

Match Tangents option, on the Bridge Section dialog, creates the feature tangent continuous to the two face sets along the selected curve on the face. Choose Match Tangents. You must select the first set of faces. Select this face in the view, and choose OK.

You must also select the string on the first set of faces. Choose Curve on the dialog and select the arc on the same face.

1558

Choose OK twice.

Creating a Fillet-Bridge Feature Using Match Tangents Specifying the Second Set of Faces and String on the Faces You must select the second set of faces. Select the top face, and choose OK.

And, as with the first face, you must select the string on the second set of faces. Choose Curve on the dialog, select this line.

1559

Choose OK twice.

Creating a Fillet-Bridge Feature Using Match Tangents Specifying a Spine String Optionally, you can select a spine string to control parameterization. If you do not select a spine string, you will have the Flow Direction control options available at the bottom of the Shape Control dialog. Perpendicular — The tangency or curvature constraint will be perpendicular to the edge. Iso Line U — The tangency or curvature constraint will be along U Lines (if applicable). Iso Line V — The tangency or curvature constraint will be along V Lines (if applicable). You will use a spine string to control parameterization. Select this solid edge as a spine string, and choose OK.

1560 The sheet is created temporarily with a temporary grid display.

Creating a Fillet-Bridge Feature Using Match Tangents Altering the Shape of the Sheet Body A Shape Control dialog displays to let you edit the shape of the newly created sheet body. The temporary grid display lets you see the shape of the surface as you modify its shape, using the options on the Shape Control dialog. Reverse Direction changes the direction of the sheet body tangency conditions. Click on Reverse Direction four times, to see the four directions that you can use. Press the Reset option to return the sheet body to its original shape. At the top of the shape control dialog are Wall Match options for Tangent and Curvature for either or both sets of faces. Using the Control Region options, you can independently control all regions of change (entire region, start region, and end region). Depending on the option you choose, the distortion will vary. You can match the first and second walls with a tangency or curvature continuous surface. Choose Curvature for the 1st Wall Match and notice how the sheet body changes. Choose Tangency for the 1st Wall Match to return the sheet to the prior state. You can control the Bridge Depth that affects the shape of the feature much the same as rho does for curves.

1561 The sheet body flattens as you move closer to zero percent, and becomes more curved as you move to 100%. Move the slider for the Bridge Depth, and notice how the sheet body changes. Press the Reset option to return the sheet body to its original shape. You can control the Bridge Skew that affects the location of maximum curvature, or reversal of curvature. You can control the Depth and Skew on the entire surface, at the start, and at the end. Move the Bridge Skew slider to change the sheet, and then Reset the feature. Choose OK on the Shape Control dialog to complete the sheet body. The sheet body is complete.

Cancel all dialogs.

Creating a Fillet-Bridge Feature Using Match Tangents Trimming the Block with the Fillet-Bridge Sheet Body These steps are brief, since trimming is covered in the Feature Modeling - Additional Topics course.

Choose the Trim Body icon

or choose Insert

Feature Operation

Trim.

Select the block, choose OK, and then select the sheet body. Choose Accept Default Direction if the direction vector points towards the upper left. The body is trimmed.

1562

Cancel the Trim Body dialog. Close all part files.

Creating A Fillet-Bridge Feature Using Match Curvatures

In this activity, you will create a fillet-bridge

Section feature, similar to this.

Creating A Fillet-Bridge Feature Using Match Curvatures Opening the Part Open part file fff_fillet_bridge_curvature.prt from the fff subdirectory, and start the Modeling application. Two sheets and three curves exist in this part file.

1563

Creating A Fillet-Bridge Feature Using Match Curvatures Starting the Feature

Choose the Section Body icon

, or Insert

Free Form Feature

Section.

Toggle off the Create Apex Curve option. Change Section Type to and Fitting Type to Cubic. Choose the fillet-bridge icon. A Bridge Section dialog of matching methods displays. Match Curvatures bridge method creates the feature curvature continuous to the two face sets. After an initial section feature is created, you can change its depth, skew, and stiffness. Choose Match Curvatures as the bridge method.

Creating A Fillet-Bridge Feature Using Match Curvatures Selecting Faces, and Edge Strings You need to select the first face and first. Select the first face and choose OK.

Select the string (single curve) on the first set of faces, and choose OK.

1564

You need to select the second face and second string. Select the second face, and choose OK. Select the string (curve) on the second set of faces, and choose OK.

Creating A Fillet-Bridge Feature Using Match Curvatures Completing the Feature You need to specify a spine string to control parameterization. Select the yellow spine string, and choose OK.

The bridge is temporarily created, and a grid is displayed.

1565

Creating A Fillet-Bridge Feature Using Match Curvatures Using Shape Control Options The Shape Control dialog displays, so you can modify the shape of the sheet. Reverse Direction reverses the tangent direction vector. Choose Reverse Direction four times, so that you see how the directions can be reversed on the sheet body. The Reset option near the bottom of the dialog will reset the feature to its original shape. Choose Reset to return the sheet to its original shape. Choose Curvature for the 1st Wall Match and notice how the shape changes. Choose Reset. Bridge Depth affects the shape of the feature much the same as rho does for curves. The sheet body flattens as you move closer to zero percent, and becomes more curved as you move to 100%. Slide the Bridge Depth slider back an forth and notice the changes that occur. Set the Bridge Depth value near 40.0. You can control the region of distortion (Entire region, Start region, or End region). Experiment with each of these as you use the sliders. You can control the Bridge Skew. Bridge Skew affects the location of maximum curvature (or reversal of curvature). Slide the Bridge Skew slider back and forth to see the changes of surface curvature. Set the Bridge Skew set to a value at 30. Experiment with other combinations of changes to the control region, bridge depth and/or skew, and stiffness. You can save the shape that you desire. Choose OK on the Shape Control dialog to complete the sheet body. Close all part files.

1566

Creating a Fillet-Bridge Feature Using Inherit Shape In this activity, you will create a fillet bridge from a spline curve.

Section feature that inherits a shape

Creating a Fillet-Bridge Feature Using Inherit Shape Opening the Part Open part file fff_fillet_bridge_inherit.prt from the fff subdirectory, and start the Modeling application. Two sheets and three curves exist in this part file.

Creating a Fillet-Bridge Feature Using Inherit Shape Starting the Feature Choose the Section Body icon

or Insert

Free Form Feature

Toggle off the Create Apex Curve option. Change Section Type and Fitting Type to Cubic.

Section.

1567

Choose the fillet-bridge icon.

Creating a Fillet-Bridge Feature Using Inherit Shape Using Inherit Shape The Bridge Section dialog displays. Inherit Shape creates the feature tangent continuous to the two face sets, and its general shape in the U direction is inherited from a curve that you select. Choose Inherit Shape. You need to select the first set of faces. Select the first face and choose OK. You need to specify a string on the first set of faces. Select the spline on the first set of faces, and choose OK. You need to select a second set of faces. Select the second face and choose OK. And, you need a string on the second set of faces. Select the spline on the second set of faces, and choose OK.

Creating a Fillet-Bridge Feature Using Inherit Shape Specifying Shape Curve Strings

1568 For this feature, you need to specify the starting shape curve string. Select the white spline curve and choose OK.

You can specify an ending shape curve string, also, and the dialog of string selection options continues to display for this purpose. You will use only one string in this model. Choose OK to indicate that you will only be using one spline curve string.

Creating a Fillet-Bridge Feature Using Inherit Shape Completing the Feature To control parameterization, you need a spine string. Select the yellow spine string and OK it.

The fillet-bridge section feature is created.

1569

The sheet is associated with the spline curve. If you change the spline curve, the filletcubic sheet body will update. Close all part files.

Creating a Point-Radius-Angle-Arc Feature Using Constant Values In this activity, you will create these point-radius-angle-arc

Section features.

1570

Creating a Point-Radius-Angle-Arc Feature Using Constant Values Opening the Part Open part file fff_point_radius_angle_arc.prt from the fff subdirectory, and start the Modeling application.

Creating a Point-Radius-Angle-Arc Feature Using Constant Values Starting the Feature Choose the Section Body icon

or Insert

Free Form Feature

Section.

You will use a face, edge curve, and spine curve to create the feature. Use the Conic Section Type. Use the Cubic Fitting Type. You can use the point-radius-angle-arc sections.

section option to create a body with circular

Choose point-radius-angle-arc. This type of feature will be defined with a starting edge curve and tangent face that you have already selected, and with the radius and angle that you will specify.

1571

Creating a Point-Radius-Angle-Arc Feature Using Constant Values Selecting Faces and Strings As with features before, you need to select the first set of faces that will become a tangent face. Select this face and choose OK.

You also need to select the string on the first set of faces. This will determine the starting edge for the new feature. Select this curve, and choose OK.

You need a spine string to control the parameterization of the new feature. Select the yellow line as a spine, and choose OK.

Creating a Point-Radius-Angle-Arc Feature Using Constant Values Specifying Radius and Angle Values A Section Options dialog displays lets you specify radius and angle parameters.

1572

A direction vector points downward from the sheet body, indicating the direction in which the radius and angle will be applied. You will use this direction. The Reverse Side of Face option lets you change the direction of the displayed vector. The radius must be greater than zero. Key in 5 as the Radius value. The angle may vary from 180 to 0 degrees, or from 0 to 180 degrees, but must not pass through zero. Key in 30 as the Angle value. Choose OK, to create the sheet body, and Fit the view. The sheet body is created.

Undo the feature so that you can create another one using laws to control the radius and angle.

Creating a Point-Radius-Angle-Arc Feature Using Constant Values Creating a Point-Radius-Angle-Arc Feature Using Radius and Angle Laws

Now, you will create a point-radius-angle-arc

feature using laws.

1573

Toggle off the Create Apex option, if needed. Choose point-radius-angle-arc.

Creating a Point-Radius-Angle-Arc Feature Using Constant Values Specifying Faces and Strings You need to select the first face. Select this face and choose OK.

You need to select the curve on the first face. Select this curve and choose OK.

Now, you need a spine string. Select the yellow line as a spine, and choose OK.

1574

Creating a Point-Radius-Angle-Arc Feature Using Constant Values Specifying Laws for Radius and Angle Choose Use Radius Law from the dialog. The dialog of law options displays. You will create a linearly changing radius ranging from a value of 5 to a value of 10. Choose the Linear law option. The linear law requires a start value and an end value. The dialog displays start and end value fields. Key in 5 as the Start Value, and 10 as the End Value, and choose OK. The Section Options dialog redisplays. You will use a cubic angular law to control the angle in a cubic progression from 10 to 25. Choose Use Angle Law, and choose Cubic as the law. Key in 10 as a Start Value for the angle, 25 as the End Value of the angle, and choose OK twice. The shape of the end of the sheet was controlled by the cubic angle law that you specified. If you do an analysis, radius, choosing a radius type U, you can visually confirm the linear gradation from 5 to 10 as the angle increased from 10 to 25.

1575

Cancel all dialogs and close all part files.

Creating an Ends-Slopes-Cubic Section Feature In this activity you will create an ends-slopes-cubic

Section feature.

Creating an Ends-Slopes-Cubic Section Feature Opening the Part Open part file fff_ends_slopes_cubic.prt from the fff subdirectory, and start the Modeling application. Five curves display in the view.

1576

Creating an Ends-Slopes-Cubic Section Feature Starting the Feature Choose the Section Body icon

or Insert

Free Form Feature

Section.

Conic does not work for ends-slopes-cubic section features. If you choose Conic when creating this section type, the system ignores your choice and uses Cubic instead. Choose Cubic for the Section Type. Use Cubic for the Fitting Type. Toggle off the Create Apex Curve option, if it is toggled on. The ends-slopes-cubic feature is created from the starting edge string and has a slope controlled by the starting slope control string. It is a cubic shape, ends at the end edge string, and is controlled by the end slope control string.

Choose the ends-slopes-cubic icon.

1577

Creating an Ends-Slopes-Cubic Section Feature Specifying the Start, End, and Slope Strings

You will use the top magenta curve as the start edge, and the top yellow curve as the start slope control string. You will be able to select the curves directly in the view. Select the start edge string and choose OK. Select the start slope control curve and choose OK.

You need to specify an end edge string. Select the end edge string and choose OK. You need an end slope control string. Select the end slope control string and choose OK.

1578

Creating an Ends-Slopes-Cubic Section Feature Completing the Feature Select the spine curve and choose OK.

The sheet body is created.

Cancel all dialogs. Close all part files.

Creating Circle Section Sheet Bodies In this activity, you will create these two circle provided.

Section features using only the lines

1579

Creating Circle Section Sheet Bodies Opening the Part Open part file fff_circle.prt from the fff subdirectory, and start the Modeling application. Two curves display in the view. In this activity, if you do not change the Modeling Preferences to a sheet body type, you will create solid features. (This is because the ends are closed planar curves.) You will change the preferences so that sheet bodies are created. Use Preferences

Modeling.

Change the Body Type to Sheet and choose OK. The silhouettes of features will display if the option is toggled on in the Visualization Preferences dialog. Choose Preferences

Visualization.

The Visualization Preferences dialog displays. (All options on this dialog are described in the Unigraphics NX online help.) Since the Visual option is already selected, the list of view attributes are displayed already. Choose the Visual tab, and then toggle on the Silhouettes option. You are now ready to create the sheet bodies. Choose OK.

1580

Creating Circle Section Sheet Bodies Starting the Feature Choose the Section Body icon

or Insert

Free Form Feature

Section.

Use the Conic Section Type. Use the Cubic Fitting Type. The Create Apex Curve option can be toggled off. The circle

option lets you create full circular section features (solid or sheet bodies).

For circle section features, a guide string, an optional orientation string, and a spine curve can be specified. The circle radius can be defined with a law or with a constant radius value. Choose the circle icon.

Creating Circle Section Sheet Bodies Specifying the Guide, Orientation, and Spine Strings You need to specify a guide string. The guide string (path of the feature) can be composed of solid faces, edges, and curves. The guide string must be tangent and continuous. Select the green spline as the guide string and choose OK.

1581 An orientation string can be used to determine the starting point of each individual section along the surface of the feature. If no orientation string is selected, the system will automatically generate one. The orientation string may not be the same string as the guide string. It may be the same as the spine, as long as the spine is not the same as the guide string. The selection of the orientation string is optional. Choose OK to tell the system that you will not be using an orientation curve. The spine should be smooth and not complex, as the complexity of the body will be reflected by the complexity of the spine. At each point on the spine, the system constructs a section plane that is perpendicular to the spine string, tangent at the point in question, and then the system intersects the plane with the guide string, generating the sections. Select this straight line as the spine string, and choose OK.

Creating Circle Section Sheet Bodies Creating a Constant Radius Circle Sheet Body The Section Radius Data dialog displays. You can specify a constant radius in the Radius field, or you can specify Use Radius Law, select a law, and specify any required parameters. Radius values must be positive (i.e., greater than zero). If the distance between the two end points of each section is not greater than twice the radius value at that point, the feature will not be created. The message "Radius less than 1/2 chord distance" will appear. You will use a constant radius value. Change the Radius value to 10 and choose OK. The sheet body feature is created, because of the setting on the Modeling Preferences dialog.

1582

The limits of the body in the V direction, along the spine, were determined by the system examining the relationship of the end points of the guide string with respect to the spine.

Determination of Body Limits

Determination of Body Limits - The limits of the body in the V direction, along the spine, are determined by the system examining the relationship of the end points of the control strings with respect to the spine. If the control strings end beyond the ends of the spine, then the spine limits determine the body limits. If the spine extends further than any of the control strings, then the body limits are determined by the end points of the shortest control string. Below, the spine determines the body limits.

When the guide string ends beyond the ends of the spine (as in this case), then the spine limits determine the body limits. When the spine ends extend beyond the guide string ends, then the body limits are determined by the ends of the guide string.

Creating Circle Section Sheet Bodies Creating Another Circle Feature

1583 Make layer 84 the work layer, make layers 41 and 83 invisible, and make layers 42 and 45 selectable. Fit the view. Two curves display in the view.

Choose the Section Body icon

or Insert

Free Form Feature

Section.

Continue using the Conic section type and Cubic fitting type. Choose the circle icon. You must select a guide string. Select the straight yellow line as the guide string and choose OK. The use of an orientation string is optional. Choose OK to tell the system that you will not be using an orientation string. You must select a spine string. Remember, the end on which you select the spine string governs which ends are start and end. Select the left end of the curved spine and choose OK.

Creating Circle Section Sheet Bodies Using a Cubic Law for the Radius The Section Radius Data dialog displays. Choose Use Radius Law. The law subfunction dialog displays.

1584 Cubic lets you define a cubic rate of change from a start point to an endpoint. You will use the Cubic radius law option. Choose the Cubic option. The radius may be zero at one end of the feature. Negative values are not permitted. Key in a Start Value of 20. Key in an End Value of 60 and choose OK. The Section Radius Data dialog redisplays, and a constant radius value is displayed, but since you have specified the system to Use Radius Law, you can simply OK this dialog. Choose OK on the Section Radius Data dialog. The section feature is created.

Rotate the model and notice how the feature is controlled by the spine curve that you used. To see both sheets, make layer 83 selectable, and make all other layers invisible. (Layer 84 will still be the work layer.) Cancel all dialogs.

Creating Circle Section Sheet Bodies Editing a Section Circle Feature You will edit the cubic radius values for the last section feature that you created. Another lesson covers other editing options, so these steps are brief. Double-click on the circle feature.

1585 The Edit Section editing dialog displays. The options on this dialog will vary, depending on the section feature that you edit.

Although you could make many different changes to the model, using the available options, you will only change the radius values for the cubic law. Choose Change Radius. A dialog displays options to change the radius law, radius parameters, or tolerance. You will modify the parameters of the cubic law. Choose Change Law Parameter to access the radius values that defined the cubic law. The dialog displays the start and end values that were defined before. Change the Start Value to 10. Change the End Value to 40 and choose OK. Choose OK until the model updates.

1586

Close all part files.

Creating a Linear-Tangent Section Feature In this activity, you will create a linear-tangent and the face of the sheet body.

Section feature between the curve

Then, you'll change the first set of faces so that the linear tangent feature is tangent to another face like this.

Creating a Linear-Tangent Section Feature Opening the Part

1587 Open part file fff_linear_tangent.prt from the fff subdirectory, and start the Modeling application. A sheet body and several curves display.

Creating a Linear-Tangent Section Feature Starting the Feature Choose the Section Body icon

or Insert

Free Form Feature

Section.

The linear-tangent option lets you create a section sheet body that is tangent to a face. To create a linear-tangent section feature, you must select a tangent face, a starting curve, and a spine.

The system will prompt you for a supporting face if the linear-tangent feature does completely intersect the tangent face at all points.

You will create the sheet body between a curve and a face as shown below in yellow. The new sheet body will be tangent to the specified face (green sheet body.)

1588

Choose the linear-tangent section icon.

Creating a Linear-Tangent Section Feature Specifying the Tangent Faces, and Starting String, and Spine You can use the green sheet body as the tangent face. Select the face as the tangent face and choose OK.

You need to specify a start string. Select the start string and choose OK. You need to select a spine string. Select the white spine string, and choose OK.

Creating a Linear-Tangent Section Feature Completing the Feature The Section Options dialog lets you enter an angle value, or choose to use an angle law. Check that the Angle value is set to 0 and choose OK on the Section Options dialog.

1589 The sheet body is created.

Cancel all dialogs.

Creating a Linear-Tangent Section Feature Editing a Linear-Tangent Section Feature You can edit the feature, making it tangent to another face. Make layer 83 Selectable and Fit the view to see another sheet body.

In the view, double-click on the newly created linear-tangent section feature.

Creating a Linear-Tangent Section Feature Replacing the First Set of Faces The Edit Section editing dialog displays options to edit this linear-tangent feature. You will replace the tangent face so that the new linear-tangent section feature is tangent to another sheet body. Choose the Replace First Set of Faces option on the Edit Section dialog.

1590 Select the largest green sheet body as the tangent face and choose OK. Choose OK until the model updates. The linear-tangent feature is now associated to a different tangent face. Refresh the view.

Close all part files.

Creating a Circular-Tangent Section Feature In this activity, you will create a circular-tangent Section feature. The new sheet body will be tangent to the specified face.

Creating a Circular-Tangent Section Feature Opening the Part Open part file fff_circular_tangent.prt from the fff subdirectory, and start the Modeling application. A sheet body and several curves display.

1591

Creating a Circular-Tangent Section Feature Starting the Feature You will create a circular-tangent section feature between the curve and the face of the sheet body.

Choose the Section Body icon

or Insert

Free Form Feature

Section.

Use the Conic Section Type and Cubic Fitting Type. Using the circular-tangent the Cover Arc direction.

option, you can create the surface in either the Fillet Arc or

To create a circular-tangent section feature, you must select the tangent face(s) to which the resulting surface will be tangent, a starting curve, and a spine string. In some cases, a supporting face at the start or end of the surface may be required as in the case of the lineartangent section surface. Choose the circular-tangent icon.

Creating a Circular-Tangent Section Feature Specifying the Tangent Faces, Starting String, and Spine You must select the tangent face.

1592 Select this face as the tangent face and choose OK.

You need to select a start string. Select the start string and choose OK. You need to select a spine string. Select the spine string and choose OK.

Creating a Circular-Tangent Section Feature Specifying the Section Options A Section Options dialog displays. The options on the dialog let you control the shape of the circular-tangent feature. The sheet will be created in a counter-clockwise direction from the starting curve to the face, as viewed from the starting direction of the spine curve. Use the Fillet Arc option. As with the circular section feature, you can use a constant radius value, or choose Use Radius Law to define the law subfunction and parameters. You will use a constant radius value.

1593 Key in a value of 1.5 as the radius of the section feature. Choose OK to create the feature.

Cancel all dialogs.

Creating a Circular-Tangent Section Feature Editing a Circular-Tangent Section Feature You will change the constant radius of this feature to a law controlled radius. Double-click on the circular-tangent feature. The Edit Section dialog displays. You will change the feature so that it uses a Cubic Radius Law with a starting radius of 1.5 and ending radius of 20. Choose Change Radius. You need to select a law option from the dialog: Change Law Type, Change Law Parameter, or Change Tolerance. Choose Change Law Type. A dialog of law options displays, so you can choose a law option. Choose Cubic. The dialog displays the current start and end values, so you can respecify the cubic law values. Key in 1.5 as the Start Value, and 20 as the End Value, and choose OK until the model updates.

1594

Close all part files.

Creating a Three-Points-Arc Section Feature In this activity, you will create this three-points-arc

Section feature.

Creating a Three-Points-Arc Section Feature Opening the Part Open part file fff_three_points_arc.prt from the fff subdirectory, and start the Modeling application. Three curves display.

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Creating a Three-Points-Arc Section Feature Starting the Feature

Choose the Section Body icon

or Insert

Free Form Feature

Section.

Use the Conic Section Type. Use the Cubic Fitting Type. This three-points-arc section feature uses a start edge string, interior string, end edge string, and a spine string. The circular arc may not span more than 180 degrees. The cross section of the sheet is a circular arc.

Choose the three-points-arc icon.

Creating a Three-Points-Arc Section Feature Specifying the Strings You must select a start string. Select the yellow curve and choose OK. You must select an interior string. Select the magenta curve and choose OK. You must select an end edge string. Select the white curve and choose OK. You must select a spine curve.

1596 Select the bottom line (white curve) again as a spine curve, and choose OK. The sheet body is created.

Cancel all dialogs. Close all part files.

Creating a Four-Points-Slope Section Feature In this activity, you will create a four-points-slope

Section feature.

Creating a Four-Points-Slope Section Feature Opening the Part Open part file fff_four_points_slope.prt from the fff subdirectory, and start the Modeling application. Five curves display.

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Creating a Four-Points-Slope Section Feature Starting the Feature

Choose the Section Body icon

or Insert

Free Form Feature

Section.

Use the Conic Section Type. Use the Cubic Fitting Type. A four-points-slope section feature starts on the starting string, passes through two interior strings, and ends on the ending string. The feature may not span more than 180 degrees. A slope control string can define the starting slope.

Choose the four-points-slope icon.

Creating a Four-Points-Slope Section Feature Specifying the Strings You must select the start edge string. Select the right-most green spline and choose OK. You must select the start slope control string.

1598 Select the right-most orange spline and choose OK. You must select the first interior string. Select the yellow curve and choose OK. You must select the second interior string. Select the left-most orange spline and choose OK. You must select the end edge string. Select the left-most green spline and choose OK. You need to select a spine curve to control the parameterization. Select the yellow curve in the middle of the view and choose OK. The sheet body is created.

Cancel all dialogs. Close all part files.

Creating an Ends-Slopes-Shoulder Section Feature In this activity, you will create this ends-slopes-shoulder curves in the part file.

Section feature using the

1599

Creating an Ends-Slopes-Shoulder Section Feature Opening the Part Open part file fff_ends_slopes_shoulder.prt from the fff subdirectory, and start the Modeling application. Five curves display.

Creating an Ends-Slopes-Shoulder Section Feature Starting the Feature

Choose the Section Body icon

or Insert

Free Form Feature

Section.

Use the Conic Section Type. Use the Cubic Fitting Type. An ends-slopes-shoulder section feature starts on the first string selected, passes through an interior string known as the shoulder, and ends on the third string. Slope is defined at the start and end by two independent slope control strings.

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Choose ends-slopes-shoulder.

Creating an Ends-Slopes-Shoulder Section Feature Specifying the Strings You must select a start edge string. Select the left-most green spline and choose OK. You must select a start slope control string. Select the left-most orange spline and choose OK. You must select a shoulder string. Select the yellow curve and choose OK. You must select an end edge string. Select the right-most green spline and choose OK. You must select an end slope control string. Select the right-most orange spline and choose OK.

1601 You need to select the spine string. Select the middle yellow curve and choose OK. The sheet body is created.

It is slightly different than the four-points-slope sheet body which you created earlier. Cancel all dialogs. Close all part files.

Creating an Ends-Slope-Arc Section Feature In this activity, you will create this ends-slope-arc

Section feature.

Creating an Ends-Slope-Arc Section Feature Opening the Part Open part file fff_ends_slope_arc.prt from the fff subdirectory, and start the Modeling application.

1602 Four curves display in the view.

Creating an Ends-Slope-Arc Section Feature Starting the Feature Choose the Section Body icon

or Insert

Free Form Feature

Section.

The ends-slope-arc feature starts on the first edge string and ends on the second edge string. The slope is determined by a control string. The cross-section is a circular arc.

Choose the ends-slope-arc icon.

1603

Creating an Ends-Slope-Arc Section Feature Selecting the Strings You must select the start edge string. Select the bottom curve and choose OK. You must select the start slope control string. Select the lower magenta curve and choose OK. You must specify an end edge string. Select the upper magenta curve and choose OK. You must select a spine string. Select the yellow curve as the spine string and choose OK. The sheet body is created.

Cancel the dialog. Close all part files.

Creating a Fillet-Rho Section Feature

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In this activity, you will create this fillet-rho provides a blend between two faces.

Section feature. In this model, it

Creating a Fillet-Rho Section Feature Opening the Part Open part file fff_fillet_rho.prt from the fff subdirectory, and start the Modeling application. Two sheet bodies and three curves display.

Creating a Fillet-Rho Section Feature Starting the Feature

1605

Choose the Section Body icon

or Insert

Free Form Feature

Section.

Use the Cubic option for the Section Type and Filleting Type options. The fillet-rho section option creates a smooth blend between two strings which lie on two bodies. The fullness of each section is controlled by the corresponding rho value.

Choose the fillet-rho icon.

Creating a Fillet-Rho Section Feature Specifying Section Strings You must select the first set of face. Select the orange sheet body and choose OK. You must select the string on the first set of faces. The final fillet-rho sheet will be tangent along this string. Select the magenta spline on the first face and choose OK. You will use the green through curves sheet body for the second set of faces. Select the green sheet body and choose OK. You need to select the string on the second set of faces. Select the magenta spline on the green face and choose OK. You will use a spine string. Select the white curve, and choose OK.

1606 A dialog of rho definition methods displays, so you can choose the rho method that you desire. The Constant and General options work in a similar way that they worked for other section features. You will use Least Tension rho for this part file. Choose Least Tension. The fillet-rho sheet body is created. Refresh the view.

Cancel all dialogs. Close all part files.

Extensions This lesson covers creating Extension sheet bodies. The types of Extension sheets that you can create include Tangential, Normal to Surface, Angled, and Circular.

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Creating Fixed Length Tangential Extensions In this activity, you will create two fixed length extensions at the top edges of two sheets bodies.

1608

About Tangent Extensions

Tangential extensions are created tangent to a face edge, or corner. Tangential extensions can be a fixed length corner extension, or a fixed length edge extension, or a

percentage of the base (edge) length.

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Creating Fixed Length Tangential Extensions Opening the Part Open part file fff_ext_tangent_fixed.prt from the fff subdirectory, and start the Modeling application.

Creating Fixed Length Tangential Extensions Checking for Trimmed Sheets

It is important that you check the face type, because you cannot create a tangential extension from a trimmed face. Find information about all objects in the part file, making sure that you will not be creating a tangential extension from any trimmed face. (Hint: Information Object, Type, Face, OK, Select All, OK.) Review the information, and notice that all faces are untrimmed B-Surfaces. Close the Information window after you've reviewed the data. Refresh the view.

Creating Fixed Length Tangential Extensions Starting a Tangential Extension Feature Choose the Extension Sheet icon Extension.

or choose Insert

Free Form Feature

1610 The Extension dialog displays options to create Tangential, Normal to Surface, Angled, or Circular extensions. In this activity, you will be using Tangential. Choose Tangential. The Tangential Extension dialog displays options to create Fixed Length or Percentage extensions. The Fixed Length option lets you create an extension of a specified length along an edge of an existing sheet.

You will use the fixed length option first. The Percentage option is covered in another activity. Choose Fixed Length. The Fixed Extension dialog displays.

Creating Fixed Length Tangential Extensions Selecting the First Tangent Face and Edge

You must select the base face from which the extension will be extended, as well as the edge. Select this sheet.

1611

The edge that you select must be an original edge of the face, not one that arose from a trimming operation. For example, you cannot use the edge of a bounded plane or an edge trimmed using fillet or chamfer. When selecting an edge, remember to place the cursor on the sheet, close to the edge. Select the upper edge of the sheet.

Creating Fixed Length Tangential Extensions Unable to Determine Edge If you get an "Unable to Determine Edge" message, it means that you selected outside the sheet. To continue, you would choose OK in the message box and reselect the edge. The U direction arrow displays the direction in which the extension will be created.

1612

Creating Fixed Length Tangential Extensions Specifying the Extension Length The dialog displays a default length for the extension. You can specify a positive or negative length. A negative length would create an extension in the direction opposite that of the displayed vector. This part is in millimeters. Enter in 200 for the Length and OK the dialog. Refresh and Fit the view if needed. The tangent extension is created. The U and V grids are displayed.

1613 Remember, you can set the grid values in the Modeling Preferences dialog. If you wanted to change them, you could use Edit Object Display.

Creating Fixed Length Tangential Extensions Creating a Second Extension The function is modal, so you can create other extensions on the same sheet. Choose Back so that you can select a different sheet body. Select the other sheet, and select its top edge. Choose OK to accept the Length of 200. Cancel the dialog, Refresh the view, and Fit the view, if needed. You have created two fixed length tangential extensions.

Close all part files.

Creating Percentage Tangential Extensions In this activity, you will create four percentage length extensions at the edges of a sheet body.

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Creating Percentage Tangential Extensions Opening the Part Open part file fff_ext_tangent_percent.prt from the fff subdirectory, and start the Modeling application. You should check the sheet body type. Remember, you cannot create a tangential extension from a trimmed edge. Find information about the faces in this part file. Notice that the sheet body has a B-Surface, and spline edge geometry. Close the information window.

Creating Percentage Tangential Extensions Starting the Tangential Percentage Feature Choose the Extension Sheet icon Extension. Choose Tangential.

or choose Insert

Free Form Feature

1615 You will create four percentage length extensions at the edges of the sheet body. You can create a tangent extension that is a percentage of the length of the base face. The Percentage option on the Tangent Extension dialog lets you create edge or corner tangential extensions that have an approximate length, which is defined as a fraction of the length of the base face.

Choose Percentage. The dialog displays edge or corner extension types. You need to specify whether you are creating an edge or corner extension. Choose Edge Extension. The Edge Extension dialog displays.

Creating Percentage Tangential Extensions Specifying Faces and Edges You need to select a face. Select the face of the sheet body.

You must specify which edge you want extended. Select the top left edge of the sheet as the location of the extension.

1616 A U direction arrow displays the direction in which the extension will be created.

Creating Percentage Tangential Extensions Specifying a Percentage Value You can specify a positive or negative percentage value. A negative value will create an extension in the direction opposite that of the displayed vector. Key in 15 in the Percentage field. Choose OK. The extension is created.

Creating Percentage Tangential Extensions Adding Additional Extensions to the Sheet You can continue to create other extensions. Choose Back and create a tangential percentage edge extension, selecting the sheet and the

1617 top right edge of the sheet. Notice as you create this extension that a V direction vector will display. Choose OK to accept 15 for the percentage. Another extension is created. Create extensions on the two remaining edges. Your part should look like the one below.

Cancel the dialog. Close all part files.

Creating Percentage Tangential Corner Extensions In this activity, you will create four percentage extensions at the corners of a sheet body.

Creating Percentage Tangential Corner Extensions Opening the Part Open part file fff_ext_tangent_corner.prt from the fff subdirectory, and start the

1618 Modeling application.

Creating Percentage Tangential Corner Extensions Starting the Percentage Corner Extension

Choose the Extension Sheet icon

or Insert

Free Form Feature

Extension.

Choose Tangential. A Tangential Extension dialog displays. Choose Percentage. Corner Extensions have an approximate length of the extension as a fraction of the length of the base face.

A dialog displays percentage extension options. You will use the corner extension option. Choose Corner Extension.

1619

Creating Percentage Tangential Corner Extensions Selecting the Face and a Corner You must select the face that will be extended. Select the largest sheet body.

You must specify which corner you want extended. The two edges meeting at the corner must be original edges of the base face, not ones that were created from trimming operations. When selecting a corner, remember to place the cursor on the sheet and close to the corner. Select the top center corner of the sheet.

Creating Percentage Tangential Corner Extensions Specifying a Percentage Value The U and V direction arrows display the directions in which the extension will be created. The dialog displays default values for U and V directions.

1620 The U and V percentages are approximations of the extension lengths in the two directions. If the same percentages are used for edge extensions and adjacent corner extensions, the extensions will have the same length and will match properly. Corner extensions are incompatible with fixed length edge extensions, since they will not blend smoothly. You can use positive or negative percentage values. A negative value creates an extension in the direction opposite that of the displayed vector. You want these corner extensions to align with the edge extensions, which were created with a percentage of 15. Enter 15 for both the U and V percentage lengths and OK the dialog. The first corner extension is created.

Creating Percentage Tangential Corner Extensions Adding the Remaining Corner Extensions Select the corner at the right side. Choose OK to accept 15 for the percentage. Create extensions on the two remaining corners. Fit the view. You have created the four corner extensions that will align correctly with the existing extensions.

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Cancel all dialogs. Close all part files.

Creating Normal to Surface Extensions In this activity, you will create four extensions normal to the surface of the base face in this part, like this.

Creating Normal to Surface Extensions Opening the Part Open part file fff_ext_normal.prt from the fff subdirectory, and start the Modeling application.

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Creating Normal to Surface Extensions Starting the Normal to Surface Extension Choose the Extension Sheet icon Extension.

or choose Insert

Free Form Feature

The extension types are listed in a dialog. Normal to Surface extensions are created normal to the base face, and along a curve that lies on the base face. The curve must lie on the sheet within the modeling tolerance for the angled extension to be created.

Choose the Normal to Surface option.

Creating Normal to Surface Extensions Selecting a Base Face and Edge You must select a face. Select the base face.

You need to select a curve on the face.

1623 You must have a curve lying on the face, to create an extension that is normal to the surface. For example, the curve could be an extracted edge curve, like the one in this part. Select this edge curve.

Creating Normal to Surface Extensions Specifying a Length After you select the curve, a direction vector displays at the middle of the curve.

This direction vector is normal to the surface and indicates the positive direction for the extension. A dialog displays a default value for the length of the Normal To Surface extension. You can enter a positive or negative value for the length. If you enter a negative value, the system will create the extension in the direction opposite to the displayed vector. Key in 2.25 as the Length value and OK the dialog. An extension is created normal to the surface of the selected face. In this part the extension is not self intersecting, that is, the sheet does not double back on itself. However, as with all other free form features, you should visually check for self intersection conditions, and eliminate those that are not intended to be present.

1624

The system approximates extensions to within a distance tolerance in the Modeling Preferences settings. A smaller distance tolerance produces more accurate approximations. The tolerance value cannot be less than .0001 inches or .00254 metric. The system ignores any minus signs in this option.

Creating Normal to Surface Extensions Adding the Remaining Extensions You need to select another curve for the extension. You can use the same values to create three more surface normal extensions. Select each of the remaining edge curves, and use 2.25 as the length value to create the remaining extensions. The finished model now has four normal to surface extensions.

Close all part files.

1625

Creating Angled Extensions In this activity, you will create these three angled extensions. You will use the curves that lie on the solid body, and the top face of the solid to create angled extensions.

Creating Angled Extensions Opening the Part Open part file fff_ext_angled.prt from the fff subdirectory, and start the Modeling application. Edge curves, a line, and a solid body display in the view.

1626

Creating Angled Extensions Starting the Angled Extension Choose the Extension Sheet icon Extension.

or choose Insert

Free Form Feature

Angled extensions are created at a specified angle to an existing base face, along a curve on the face. The curve must lie within the modeling distance tolerance of the face. Angled extensions are always approximations.

Direction vectors establish a reference for measuring angle of extension. Choose Angled. Both normal and tangential extensions are special cases of angled extensions. If the specified angle is 90°, the angled extension is created normal to base surface. If the specified angle is 0°, the angled extension is similar to (but not identical to) a tangential extension.

Creating Angled Extensions Specifying a Face and Curve on the Face You must select a face for the extension. Select the top face.

1627

You need to select a curve from which the extension will start. The curve must lie on the face that was selected for the extension. In this part, an edge curve was extracted. You will use this extracted edge curve to create the extension. Select this edge curve.

Creating Angled Extensions Specifying Parameters Direction vectors and degrees display to establish a reference for measuring the angle of the extension. One vector (0) is in the tangent plane of the face and normal to the curve, while the other is normal (90) to the face.

1628

Positive angles will create a positive rotation from the first vector (0) towards the second vector (90). For example, 45° will angle the extension midway between 0° and 90°. A dialog displays default values for the length and angle of the extension. Key in the following parameters: use a Length of 1.25, an Angle of 45, and OK the dialog to complete the feature. The angled extension is displayed.

1629

Creating Angled Extensions Creating the Next Angled Extension The extension function is modal so that you can continue to create angled extensions from the top face. If you wanted to select a different face, you would choose the Back option and then select the next face. You will use the straight line located between the endpoints of two other edges. Select the straight line located on the top face. Direction vectors display to establish a reference for measuring the angle of the extension.

You will make this extension 60° away from the surface normal. Key in a Length of 0.74, an Angle of 60, and OK the dialog. The angled extension is created.

1630

Creating Angled Extensions Creating the Last Angled Extension To create a tangential type of extension on a trimmed surface, you can use the Angled extension. Refresh the view. Create an angled extension on the top face, using the other white curved edge curve, with an angle of 180, and the default length value of 0.74. Refresh the view.

1631 Notice that this extension is similar to a Fixed Length Tangential extension. Because the top face is a trimmed B-Surface, you cannot use the Fixed Length Tangential Extension option. (If you were to try to, you would receive a message: Unable to Determine Edge.) Close all part files.

Creating Fixed Length Circular Extensions In this activity, you will create a fixed length circular extension like this.

Creating Fixed Length Circular Extensions Opening the Part Open part file fff_ext_circular_fixed.prt from the fff subdirectory, and start the Modeling application.

Creating Fixed Length Circular Extensions Starting the Fixed Length Circular Extension Choose the Extension Sheet icon Extension. A dialog of extension types displays.

or choose Insert

Free Form Feature

1632 Circular extensions are created tangent to a face edge. The extension can be of a Fixed Length or a Percentage of the base length.

Choose the Circular option. You will created a fixed length extension on the right edge. Choose Fixed Length.

Creating Fixed Length Circular Extensions Specifying the Face, Edge, and Length You need to select a face. Select the face of the sheet body. You need to select an edge. Select this edge.

The vector displays the U direction in the view. A dialog displays a default value for the fixed length circular extension. Key in a value of 0.5 for the length of the extension, and OK the dialog. Cancel the dialog.

1633 Fit the view. The circular extension is complete.

Close all part files.

Creating Percentage Circular Extension In this activity, you will create a circular percentage extension.

Creating Percentage Circular Extension Opening the Part This activity is quite similar to others in this lesson, so the steps are very brief. Open part file fff_ext_circular_percent.prt from the fff subdirectory, and start the Modeling application.

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Creating Percentage Circular Extension Starting the Percentage Circular Extension Choose the Extension Sheet icon Extension.

or choose Insert

Free Form Feature

Choose Circular. Choose Percentage. Creating Percentage Circular Extension Completing the Circular Extension Select the face.

Select this edge.

A dialog with a default percentage value displays. Key in a value of 50 for the percentage extension and OK the dialog. Fit the view.

1635 Cancel the dialog. The percentage circular extension is created.

Law Extension This lesson covers creating Law Extensions.

The Law Extension option lets you create an associative and parametric law controlled extension for an existing base sheet, based on laws for length and angle.

1636 You can use the option to create flanges or extensions where a particular direction is important or a reference to an existing face is necessary (for example, in die design or mold design, draft direction plays an important role while creating parting surfaces).

Creating a Law Extension Surface In this activity, you will create a law extension feature.

Then, you will edit the feature to look like this.

Creating a Law Extension Surface Opening the Part Open the part file fff_law_extension_1.prt from the fff subdirectory, and start the Modeling application.

1637

Creating a Law Extension Surface Starting the Law Extension

Choose the Law Extension icon Extension.

or choose Insert

Free Form Feature

Law

The Law Extension dialog displays. You can use the Filter options when you are selecting the Curve String and Spine String.

1638

Merge Faces if Possible, when toggled on, creates the feature as a single sheet body whenever possible. If it is toggled off, the feature will be a single sheet body with multiple faces, each corresponding to a segment of the base curve. If the base Curve String formed out of the segments is not smooth and the Merge Faces if Possible option is checked on, then the law extension feature is created consisting of multiple faces, as long as the reference direction does not make the sheet body break or create faces that intersect each other. Otherwise the feature cannot be created. Use the Merge Faces if Possible option toggled on.

Creating a Law Extension Surface Selecting the Base String First you must select a base curve string from which the extension will be created.

1639

The Curve String selection step is active and lets you select a base curve or edge string that the system will use to define the surface profile at its base edge. You should use a smooth curve string, even though some cases of a non-smooth curve string will work. Smooth means that the curve segments satisfy tangential continuity, or the deviation of tangents are within the value specified for the Angle Tolerance on the Modeling Preferences dialog. For the base curve, you will use the orange curve located approximately in the middle of the sheet body. Remember, you can set the Filter to select Any, Edge, Curve and Sketch. With the Curve String surface.

selection step active, select the curve in the middle of the

If you want to create the law extension on both sides of the base curve string, use the Extend on both sides option. Toggle off the Extend on both sides option, because you will not be creating an extension on both sides of the face. If you used this option in this part file, your finished model would look like this. Notice that the extension is created above and below the base face.

1640 Extend on both sides, when toggled on, causes the law extension to be created on both sides of the base Curve String, using the same Length Law and Angle Law parameters on both sides. The Confirm Upon Apply option lets you preview the results, and accept, reject or analyze them. Leave Confirm Upon Apply toggled off.

Creating a Law Extension Surface Specifying a Reference Method Next, you must specify a reference method and use the appropriate selection step to define a reference direction.

Reference Methods for Extension Surfaces

The system uses a Reference Method to construct the extension surface. You can establish the reference by using faces, or by using the vector methods. When you choose the Faces option, you use the Base Face selection step to select one or more faces to form a reference coordinate system for the extension surface. The reference coordinate system is formed at the midpoint of the base Curve String (such that the 90 degree direction is the normal to the face at the mid point, and 0 degree is a vector perpendicular to the plane containing the normal to the face and tangent to the base Curve String at its midpoint). When you choose the Vector option, you use the Vector selection step to specify a single coordinate system that is calculated and used at every point along the base curve string to define the extension surface. The orientation of this coordinate system is determined by aligning the zero degree angle parallel to the vector direction, and the 90 degree axis perpendicular to the plane defined by the zero degree axis and the base Curve String tangent vector. This reference plane calculation is performed at the Base Curve String midpoint.

Since you will be using the face of the sheet in this activity, you need to set the Reference Method to Faces. Make sure that the Reference Method is set to Faces on the dialog.

1641

Creating a Law Extension Surface Specifying the Base Face and Spine

The Base Face selection step

is used with the Reference Method of Faces.

You can select multiple faces on the same or separate bodies as long as the faces can be sewn together using the Sew option. Choose the Base Face

selection step.

Remember, you can set the Filter to select Any, Edge, Curve and Sketch. Select the surface of the sheet body to define the reference method.

Using a Spine String is optional. Specifying a spine string changes the way in which the system determines the orientation of the local CSYS, such that the plane that is perpendicular to the spine string determines the plane in which the Angle is measured. If you specify a spine with the Spine String option, the system will always try to merge faces, regardless of the status of the Merge Faces if Possible option. Choose the Spine String selection step. The system displays direction coneheads to show you the 0 and 90 degrees axes of the reference direction you have defined. The zero and 90 degree direction vectors can help you in assigning values for the Angle Law.

1642

The 0 degree orientation for the angle is parallel to the projection of the local Reference direction where this plane crosses the base Curve String. If the plane does not intersect the base curve string, no section is calculated. You will not use a spine string in this activity.

Creating a Law Extension Surface Specifying the Laws

The Law Length and Angle Law options can be set to one of several options: Constant, Linear, Cubic, or General.

Laws for Length and Angle for Extension Surfaces

The Length Law and Values control the length of the extension. The Constant Law creates an extension surface that has a constant length, along the entire curve string. The Linear Law creates an extension surface with a length that varies linearly from the start value to the end value, as the extension moves from the start point of the curve string to the end point of the curve string. You need to use a Start Value and an End Value. The length can be zero at one end, but not both ends. The Cubic Law creates an extension surface with a length that varies non-linearly from the start value to the end value, as the extension moves from the start point of the curve string to the end of the curve string. This occurs even if a Spine Curve has been specified that prevents the Entire surface from being created. You need to use a Start Value and an End Value. The length can be zero at one end, but not both ends. The General Law starts the Law dialog, which provides additional law methods that you can use to specify the Length Law.

You will use a Cubic Law to create a non-linearly varying length extension feature.

1643 Choose Cubic as the Length Law. You need to provide the start and end values for the Cubic law. Key in the following values: use a Start Value of 15.0, and an End Value of 40.0. The Angle Law and values control the angle of the extension. You will use a Cubic Law to create a non-linearly varying angle extension feature. Choose Cubic as the Angle Law. You need to enter a start value and end value for the angles. Key in the following values: use a Start Value of 250, and an End Value of 280. You have specified all of the parameters required to create the extension feature. OK the Law Extension dialog. The law extension is created. The extension is approximated using the distance tolerance specified on the Modeling Preferences dialog.

Creating a Law Extension Surface Editing the Law Extension Sometimes it is easier to view the model in a shaded mode. Shade and rotate the view to review the surfaces.

1644

Return to wireframe display mode. Now that you have created the law extension feature, you will edit it by changing the base curve. However, you can change other parameters of this associative, parametric feature. Double-Click on the Extension feature to edit the feature parameters. The Law Extension dialog used for editing the feature is identical to that used for creating it, except that you have the option of changing the distance tolerance and angle tolerance values for this feature.

Distance and Angle Tolerances for Law Extension Surfaces

Distance Tolerance specifies the maximum distance between the Curve String and the Base Face. The default value is taken from the modeling preferences. The default values for the Distance and Angle Tolerances are taken from the modeling preferences.

Do not change the distance or angle tolerance values.

Creating a Law Extension Surface Changing the Length Law Type and Values Now, you can edit any of the feature parameters, but you will only change the length law type and values. Change the Length Law to Linear. Change the Start Value to 25. Change the End Value to 45. Do not need to change the angle law type or values. Since you will not make any other changes to the model, you can complete the change.

1645 Choose OK until the part updates. Refresh the view.

Creating a Law Extension Surface Changing the Base Curve for the Law Extension You will change the base curve, and update the model. The new curve is on layer 42. Make layer 42 Selectable.

You will reassign the Extension Surface to this new curve. Double-click on the extension surface. The Law Extension dialog displays.

Creating a Law Extension Surface Selecting a New Base Curve

You need to select the new curve string to edit the model.

1646

With the Curve String

selection step active, select the new curve.

Creating a Law Extension Surface Deselecting the Original Base Curve You need to deselect the original curve string that you used in the feature. With the Curve String of the extension surface).

selection step active, shift-select the original curve (at the base

Since you will not make any other changes to the model, you can complete the activity. Choose OK on the dialog until the model updates. Refresh the view, and shade the model.

1647

Close all part files.

Fillet Surface This lesson covers creating Fillet Surface features.

You can create conic or circular Fillet Surfaces between two faces of a solid and/or sheet body. The fillet surfaces can have a constant radius, or vary linearly, or curvilinearly.

Creating a Constant Circular Fillet In this activity, you will create this constant, circular fillet surface at the intersection of the two sheet bodies.

1648

Creating a Constant Circular Fillet Opening the Part Open part file fff_fillet_1.prt from the fff subdirectory, and start the Modeling application. Turn off the display of the WCS, because you will not need it. The part file contains free form sheets, lines, and curves.

Remember, as with other free form features, the Modeling distance tolerance, lets you define the accuracy. If you need to create a blend where more than two faces are involved, you need to use the Face Blend option, which is described in another lesson.

1649

Locating the Fillet

There are four quadrants in which you can create the fillet. You will create the fillet in the upper left quadrant.

Creating a Constant Circular Fillet Starting the Fillet

Choose the Fillet Surface icon

or Insert

Free Form Feature

Fillet.

A Fillet dialog displays.

Overlaps of Faces for Fillet Features

In this part, the two faces intersect. However, if the faces did not intersect, or did not touch, you would need to specify a fillet radius large enough so that the edges of the fillet would overlap both selected faces. Otherwise, the fillet would not be created.

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Also, if the fillet just touched the edges of the selected faces but did not overlap them, you could get undesirable results. When you are creating a fillet between two spherical or cylindrical faces, the faces need not intersect.

Creating a Constant Circular Fillet Selecting the First Face You need to select the first face. Select the upper part of the vertical sheet as the first tangent face. A face normal vector displays. The vector orientation determines the quadrant in which the fillet will be created. Both vectors must to point into the upper left quadrant to create a fillet there. A dialog of Yes, No options displays. You need to check the vectors and respond to the system whether the normal direction is OK. Choose Yes if the direction vector points to the left, or No if the direction vector points to the right. (Choosing No will flip the vector.)

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Creating a Constant Circular Fillet Selecting the Second Face and Spine You need to select the second face. Select the other sheet for the second face. Choose Yes if the direction vector points upward, or No if the direction vector points downward.

You can select a spine curve, however, a spine curve is not required for a circular fillet. Choose OK, because you will not use a spine curve.

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Creating a Constant Circular Fillet Specifying a Fillet Creation Type

A dialog displays two options: create fillet, and create curve. The Create Fillet toggle lets you create the fillet (yes) or not create it (no). The Create Curve toggle lets you create the offset intersection curve between the two faces. The curve would have the contour of the selected fillet type and the entered parameters (values). The intersection curve could be used as a spine curve for creating a more complicated fillet. The curve could also be used in trimming. Choose OK to accept the defaults. A dialog displays Circular and Conic fillet cross section types.

Choose Circular as the cross section type.

Creating a Constant Circular Fillet Specifying Rho

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Three rho functions are available: Constant, Linear, and S-shaped. If you had selected a spine curve, the General option would appear on the list also. The Constant option causes the rho value to be constant along the fillet. Choose Constant. The Linear option would cause the rho values to be linearly tapered between starting and ending values corresponding to the start and end of the fillet. The S-shaped option would cause the rho values to follow an s-shaped curve.

Creating a Constant Circular Fillet Specifying a Start Limit Point

You must select the start and end points for the fillet surface. A dialog displays your limiting options: limit point, limit face, and limit plane.

Limit Points for a Constant Radius Fillet

For a constant radius fillet, you are not required to select limit points (start and end), because the system will create a start point for the fillet and trace edge to edge. If you do not define limits in this part, the fillet will not extend to the ends of both sheets, like this.

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You will limit the fillet by the endpoints of the line. Choose Limit Point. The Point Constructor dialog displays to assist you in the selection of points. Select the left end of the straight line as the first limit point.

Creating a Constant Circular Fillet Specifying the Radius

1655 You are prompted to specify a radius for the circular constant fillet. The Fillet dialog displays a default radius value. Choose OK to accept the default radius of 1.00. A set of temporary points display to show the size of the radius for the fillet, and a temporary vector displays the direction for the fillet.

A dialog of Yes/No options displays, so that you can confirm the direction vectors. The vector should point toward the sheets, from the first selected limit point toward the last limit point. Choose Yes, if your vector appears as illustrated above. (Choosing No would flip the direction.)

Creating a Constant Circular Fillet Specifying the Second Limit You need to specify the second limit point. Choose Limit Point from the dialog. Select the right end of the straight line as the second limit point.

1656

Creating a Constant Circular Fillet Completing the Fillet Choose Yes to accept the second set of fillet points. A circular fillet with a constant radius is created tangent to the two faces. Refresh your view.

The fillet surface is an unparameterized feature, and no associativity exists. If you modified or deleted the sheets that you used for the selection of the first and second faces, the fillet surface would remain as it was created. It would not change. If you want a fillet that is associated to adjacent faces, you should use another feature creation method. You can use the Trim Body function to trim the fillet to the edges of the adjacent faces.

1657 Close all part files.

Creating a General Circular Fillet In this activity, you will create a general, circular fillet in the upper left quadrant.

Creating a General Circular Fillet Opening the Part Open part file fff_fillet_1.prt from the fff subdirectory, and start the Modeling application. Turn off the display of the WCS, because you will not need it.

1658 This fillet that you will create will have a small radius at the left end, and then progressively increase toward the right.

Creating a General Circular Fillet Selecting the First Face Choose the Fillet Surface icon

or Insert

Free Form Feature

Fillet.

You need to select a face. Select the vertical face.

If the direction vector points to the left, choose Yes. If it points to the right, choose No.

Creating a General Circular Fillet Selecting the Second Face Select the horizontal face, and choose the appropriate vector direction option.

1659

Creating a General Circular Fillet Selecting a Spine Curve You will use a spine curve to control the fillet. The spine curve acts as a guide for the fillet. This spline is located at the intersection of the two sheets. Select the spine curve.

Choose OK to accept the default options for the fillet.

1660

Creating a General Circular Fillet Specifying the Rho and Fillet Type You need to specify a cross section type. Choose Circular. The dialog displays four rho function options: Constant, Linear, S-shaped, and General. The Constant, Linear, and S-shaped options were described earlier in this lesson. The General option causes the rho values to vary continuously between the specified values.

Choose General.

Creating a General Circular Fillet Specifying the First Limit and Radius The Point Constructor dialog displays to assist you to indicate the start point. Select the left end of the straight line as a start point.

1661

A dialog displays the default radius. Key in a radius of .01 and choose OK. A vector and points display. The vector should point toward the sheets.

Creating a General Circular Fillet Specifying Another Limit and Radius Because you have selected General as the rho function, you could specify additional points and values at this time. You will only specify the last (second) end point. Select the right end of the straight line as the second point.

1662 Key in a radius of 1.5, and choose OK twice. The fillet is created.

Creating a General Circular Fillet The Completed Fillet Refresh the view. It follows the spine curve and gradually grows larger from the left to right.

Close the part file.

Creating a Linear Conic Fillet In this activity, you will create a linear conic fillet to see how it compares with the general circular fillet.

1663

Creating a Linear Conic Fillet Opening the Part Open part file fff_fillet_1.prt from the fff subdirectory, and start the Modeling application.

Creating a Linear Conic Fillet Starting the Fillet

Choose the Fillet Surface icon

or Insert

Free Form Feature

Turn off the display of the WCS, because you will not need it.

Fillet.

1664 Select the vertical face, and make the direction vector point to the left. Select horizontal face, and make the direction vector point upward.

Creating a Linear Conic Fillet Specifying the Cross Section and Fillet Type You will not use a spine curve this time. Choose OK. Choose OK to accept the default to create a fillet but no spline curve. Choose Conic as the cross section type. Choose Linear to create a linear, conic fillet. Because you are creating a conic, linear fillet, you can choose one of these rho functions: Same as Fillet Type, or Least Tension. The Same As Fillet Type option results in rho values that are computed in the same way as the fillet type you are using, constant, linear, s-shaped or general. The Least Tension option results in rho values that are computed from the input geometry according to a least-tension condition. In most cases this will produce an elliptical cross section. Choose Same As Fillet Type as the rho function. Choose Limit Point and select the left end of the straight line as a limit point.

1665

Creating a Linear Conic Fillet Specifying Values for the First Limit Point The Fillet dialog displays default values for the Radius, Ratio, and Rho. The Ratio value is used to compute the radius or offset value for the second face. Its value is the ratio of the distances from the selected faces to the offset intersection point.

Above, R1 is the distance (radius) from the offset intersection point to the first selected face, and R2 is the distance (radius) from the offset intersection point to the second selected face. (R2 = Ratio × R1) Use the default value 1.00 for the Radius. Key in 0.5 in the Ratio field. When you use a ratio value that is less than 1, the larger offset value will be from the first selected face. When the ratio value is greater than 1, the larger offset value will be from the second selected face.

1666

If the ratio value is equal to 1, then the offset values will be equal, creating a circular cross section. The Rho value determines the fullness of each conic section. It represents a fraction of the distance from the end points to the apex, and can have a value ranging from 0.001 to 0.900. The Rho value determines the shape of the conic: Parabola: rho = 0.5 Ellipse: 0.0 < rho < 0.5 Hyperbola: 0.5 < rho < 1.0 The conic shape is related to the Rho value. A small value will produce a very flat conic, while a large rho value (0.900) will produce a very pointed conic. For more information about rho values, please refer to the Unigraphics NX online help. Key in .75 in the Rho field. Choose OK in the dialog. The direction vectors should display like this.

Choose Yes to accept the directions.

1667

Creating a Linear Conic Fillet Specifying the Values for the Second Limit Point You need to specify the next limit. Choose Limit Point to specify the second limit. Select the right end of the straight line as a second limit point. The Fillet dialog displays with the default radius, ratio, and rho values. Key in the following parameters for this end point: Radius of 3.0, Ratio of 0.5, Rho of 0.75, and choose OK. The fillet points display. and you need to provide a confirmation of the points. Choose Yes to confirm the points. The fillet is created. Cancel the dialog. Refresh your view.

Because you entered a ratio value of less than 1, the larger offset will be taken from the first selected face. Close all part files.

1668

Face Blend This lesson covers creating Face Blends.

The Face Blend option lets you to create trimmed or non-trimmed spherical, conical, disc, and isoparametric cross-section blends that are tangent to two sets of faces. You can use the Face Blend option to create a blend on solid bodies or on sheet bodies.

Creating a Trimmed Attached Constant Blend In this activity, you will create this trimmed constant radius spherical blend attached to two sheet bodies.

1669

Creating a Trimmed Attached Constant Blend Opening the Part Open part file fff_faceblend_sphere.prt from the fff subdirectory, and start the Modeling application. The part contains two sheet bodies that intersect each other. The part is similar to one you used in the section on Fillet sheet bodies.

Creating a Trimmed Attached Constant Blend Starting the Feature

Choose the Face Blend icon Operation Face Blend. The Face Blend dialog displays.

on the Feature Operation toobar, or Insert

Feature

1670

You can select any of the four icons at the top of the dialog anytime during the creation process. The Include Tangent Faces option lets you select all faces of a tangent string of edges by selecting one of the tangent faces. If you use this, the system automatically selects the remaining tangent faces of the same body. This option extends the face blend until it comes to a non-smooth edge. The End Tangent Overflow option limits the edge blending boundary on the last sequence of blended edges that lie beyond a trimmed face. You will not use the End Tangent Overflow. Toggle off the End Tangent Overflow option.

1671 Toggle off the Enable Blend Preview option near the bottom of the dialog.

Creating a Trimmed Attached Constant Blend Specifying the Attachment Method

You must specify an attachment method. The Trim & Attach All option trims the blend and attaches it to the underlying sets of faces. For this model, the result will be one sheet body. Use the Trim & Attach All attachment method, so that the blend will be trimmed and attached to the selected faces. The Trim All option trims the blend and underlying face sets; so, the model will have an identical shape (as with Trim & Attach All); but, three sheets will exist.

The other trim options would create these results, each with three sheet bodies.

1672

Creating a Trimmed Attached Constant Blend Specifying the Blend Type The Blend Type options include Sphere, Conic, Disc, and Isoparameter. The Sphere blend type is a "rolling ball" blend whose cross section lies in a plane normal to the two selected sets of faces. The Conic face blend has a conic cross-section, which you can control with two offsets and a rho. (You will use this option later.) The Disc blend is a variable radius blend whose cross section lies in a plane orthogonal to a spine string. The blend radius is defined by the Law Subfunction. (You will use this option later.) The Isoparameter blend is a specialized blend used primarily for turbine blades. For these types of surfaces, an isoparametric blend may produce good results when other blend types fail. The surface definition of this blend is based on that of a disc blend, but the planes containing the section curves are adjusted, based on the isoparameters of the first set of faces. Use the Sphere blend type.

Creating a Trimmed Attached Constant Blend Specifying the Values The Radius Method options for a Sphere blend type are Constant, Law Controlled, and Tangency Controlled.

1673

Law Controlled lets you define a variable radius at individual points along a spine curve according to the Law Subfunction. Tangency Controlled lets you control the blend radius by specifying curves lying on one of the walls, where the blend surface and curves are constrained to remain tangent. Constant allows only positive values for constant radius blends. You can choose a tangent string to constrain the constant blend radius. Use the Constant radius method option. For the Constant radius method, you must provide a positive radius value, greater than zero. Key .75 into the Radius field. The tolerance determines the accuracy of the blend to the faces and the degree of smoothness for transitions from one face to another. As a rule, the edge of the blend that would be created on the adjoining face cannot deviate by more than the tolerance from the edge of the blend on the current face. The default tolerance is taken from the Modeling Preferences dialog, but you can change it. Use the default Tolerance of 0.001.

Creating a Trimmed Attached Constant Blend Specifying the First Set of Faces The Filter menu lets you control what geometry is selectable. This option is useful in complex parts.

1674 Use the filter option Faces. There are four possible quadrants in which you could create the face blend feature. You will be creating the blend in the upper left quadrant.

The First Set icon

is highlighted, so you can select the first set of faces for the blend.

Select the vertical face as the first face. A face normal vector displays.

The location of the vector varies, depending on your selection. The vector direction determines the quadrant in which the blend is created.

1675 The vector must point toward the center of the desired blend, and in this case, toward the left. If the vector points to the right, choose the Reverse Normal option on the dialog so that the vector points to the left.

Creating a Trimmed Attached Constant Blend Specifying the Second Set of Faces You must specify the second face for the blend. Choose the Second Set icon. Select the horizontal face for the second set. If the vector points downward, choose Reverse Normal, so that the blend is created in the upper left quadrant. The Confirm Upon Apply option lets you analyze the feature before you create it. You do not need to use this now. Toggle off the Confirm Upon Apply option, if needed. Choose Apply to create the attached, trimmed blend.

Cancel the dialog.

Creating a Trimmed Attached Constant Blend Editing a Face Blend Feature You will change the radius of the blend and update the model.

1676 Double-click on the face blend feature in the view. The Edit Face Blend dialog displays. It is similar to the Face Blend dialog. Change the Radius to 1.5 as the new radius value. Choose OK until the model updates.

Close the part file.

Creating a Constant Blend Between Two Separated Sheet Bodies In this activity, you will create a face blend between two separate sheet bodies. Then, you will thicken the model.

1677

Creating a Constant Blend Between Two Separated Sheet Bodies Opening the Part Open fff_faceblend_2_bodies.prt from the fff subdirectory, and start Modeling application. These two cylindrical sheet bodies do not touch.

Creating a Constant Blend Between Two Separated Sheet Bodies Rotating the View You will want the separate bodies displayed differently before you start the face blend creation. You can rotate the model to determine if the direction vectors point in the correct directions. Rotate the view so that the space between the two cylinders is visible like this.

1678

Creating a Constant Blend Between Two Separated Sheet Bodies Starting the Feature and Selecting the First Set of Faces Choose the Face Blend icon

or Insert

Feature Operation

Face Blend.

The First Set icon is highlighted on the dialog. Before you select the first set of faces, you will change the filter option. Choose Faces as the filter option. Select the first cylindrical face, and if necessary, choose the Reverse Normal option to change the direction vector so that it points into the blend.

Creating a Constant Blend Between Two Separated Sheet Bodies Selecting the Second Set of Faces

Choose the Second Set icon. Now, you can select the second set of faces.

1679 Select the cylindrical face of the left cylinder. The vector should point away from the body and not into it.

Use the Trim & Attach All option so that the blend is trimmed.

Creating a Constant Blend Between Two Separated Sheet Bodies Specifying the Radius and Tolerance Use a Sphere Blend Type. Use a Constant Radius Method. Key in a value of 0.25 for the Radius. You will use the default Tolerance of .001. Choose OK twice. The blend is created and united so that the part is one feature. The shaded model looks like this.

Creating a Constant Blend Between Two Separated Sheet Bodies Thickening the Sheet into a Solid Body

1680 Thicken is covered in another lesson, but you will use it now to thicken the sheet body into a solid body.

Choose the Thicken Sheet icon

or Insert

Form Feature

Thicken Sheet.

A Thicken Sheet dialog displays. Use all the default values. Select the feature in the view. Choose OK on the Thicken Sheet dialog. The body now has a thickness of 0.1 inch. The shaded model looks like this.

Close the part file.

Creating a Constant Radius Blend that Includes all Tangent Faces In this activity, you will create blends on a solid body. The blends will be tangent to all faces like this.

1681

Creating a Constant Radius Blend that Includes all Tangent Faces Opening the Part Open part file fff_faceblend_tangent_faces.prt from the fff subdirectory, and start the Modeling application.

Creating a Constant Radius Blend that Includes all Tangent Faces Starting the Feature You need to create an Edge Blend at the base of the post before you create the Face Blend.

Choose the Edge Blend icon

or Insert

Key in 0.5 as a Default Radius value. Use Edge as the Blend Type. Select the edge at the base of the post.

Feature Operation

Edge Blend.

1682

Choose Apply to complete the first blend.

Creating a Constant Radius Blend that Includes all Tangent Faces Specifying the First Set of Faces You can now blend the post to the right side.

Choose the Face Blend icon

or Insert

Feature Operation

Face Blend.

Set the Filter to All. The First Set icon is highlighted, so you can select the first set of faces. Select the first face.

1683 Reverse (Reverse Normal) the direction vector if necessary so that the vector points to the left, away from the part.

Creating a Constant Radius Blend that Includes all Tangent Faces Specifying the Second Set of Faces Now, you need to select the second set of faces/bodies for the blend. Choose the Second Set icon. Select the conical face of the boss.

Reverse (Reverse Normal) the arrow if it points into the post.

Creating a Constant Radius Blend that Includes all Tangent Faces Specifying Remaining Parameters

When the Include Tangent Faces option is toggled on, the system automatically selects all faces that are tangent to the face that you select. The face blend will continue until a nonsmooth edge is crossed. The use of this option will not result in faces being added to either face set; instead, the system will determine the tangent faces as the blend is being applied. Toggle the Include Tangent Faces to on. Toggle off the End Tangent Overflow option. Set the Attachment Method of Trim & Attach All, use a Blend Type of Sphere, set the Radius Method to Constant, use a 0.5 Radius, and Tolerance of .001.

1684 You can check your prior selections by clicking on the icons in the top of the Face Blend dialog. Choose the First Set icon to see that the first face highlights. The system selected tangent faces will not highlight. Choose the Second Set icon to see that the second face highlights. The system-selected tangent faces will not highlight. Choose Apply to complete the blend.

Close all part files.

Creating a Linearly Varying Law Controlled Blend on Sheet Bodies In this activity, you will create a linearly varying blend between two sets of selected faces.

Creating a Linearly Varying Law Controlled Blend on Sheet Bodies

1685

Opening the Part Open part fff_faceblend_linear_law.prt from the fff subdirectory, and start the Modeling application. The part consists of many sheets, and curves.

Creating a Linearly Varying Law Controlled Blend on Sheet Bodies Starting the Face Blend

Choose the Face Blend icon

or Insert

Feature Operation

Face Blend.

The Face Blend dialog displays. You can use the All filter option since this part is simple. Use the Trim & Attach All attachment option so that the blended and faces will be trimmed and sewn together. The Law Controlled option lets you define a variable radius at individual points along a spine curve according to the Law Subfunction. Change the Radius Method to Law Controlled.

Creating a Linearly Varying Law Controlled Blend on Sheet Bodies Specifying a Linear Law and Spine Curve

A dialog of law functions displays, so you can choose the desired blend radius law. As mentioned before, you will create a linearly varying blend between two sets of selected faces.

1686 Choose Linear. Now, you need to specify the spine string. Multiple sections can be contained in a spine string, but this part has a single spline. Choose Curve on the dialog, select the spine string that extends along the edge of the three lower faces, and choose OK until the Law Controlled dialog displays.

A Law Controlled dialog contains default start and end radius values. For a linearly varying radius blend you must define a start radius and an end radius. The values must be greater than or equal to zero. Key in 0.25 for the Start Value of the blend, 0.50 for the End Value, and choose OK.

Creating a Linearly Varying Law Controlled Blend on Sheet Bodies Specifying the First Set of Faces You need to specify the first set of faces. Select this face for the first set.

The first face highlights, and a direction vector displays.

1687 If necessary, choose Reverse Normal to make the vector point upward. Also, select this other face for the first set.

The direction vector will not display when the 2nd face highlights, because the existing vector direction specifies the quadrant. You have completed selections for the first set of faces for the blend.

Creating a Linearly Varying Law Controlled Blend on Sheet Bodies Specifying the Second Set of Faces Now, you need to specify the second set of faces. Choose the Second Set icon. Select this face of the second set.

Reverse the vector if it points downward. Select the two adjacent faces.

1688

Creating a Linearly Varying Law Controlled Blend on Sheet Bodies Completing the Law Controlled Blend Choose Apply. The blend is complete.

Close all part files.

Creating a Disc Blend

In this activity, you will create this Disc blend.

1689

Creating a Disc Blend Opening the Part Open part file fff_faceblend_disc.prt from the fff subdirectory, and start the Modeling application. The shaded view would look like this.

Creating a Disc Blend Starting the Disc Face Blend Choose the Face Blend icon

or Insert

Feature Operation

Face Blend.

1690 The Blend Type of Disc creates a variable radius blend whose cross-section lies in a plane orthogonal to a spine string. The blend radius is defined by the Law Subfunction. You need to use the Disc blend type to create a blend at the intersection of the two irregular faces. Change the Blend type to Disc. Use the Attachment Method Trim & Attach All. Toggle off the End Tangent Overflow option, if needed. Notice that the Include Tangent Faces option is not available for the disc blend type.

Creating a Disc Blend Selecting the First Set of Faces

You need to specify the first set of faces. Select the first face, and make sure the vector points away from the solid body.

Creating a Disc Blend Selecting the Second Set of Faces Now, you need to specify the second set of faces. Choose the Second Set icon.

1691 Remember, both vectors need to point towards the center of the desired blend radius. Select the second face, and make sure the vector points away from the solid.

Creating a Disc Blend Specifying the Law For Disc blends, you must define the radius with a law. Choose the Define Law option on the dialog. A dialog displays options for the law function, so you can choose one of the law options. Choose Linear. To create a Disc blend, you must use a spine string. Although you will select the spine now, you could define a spine string at any time by choosing Define Spine String, then selecting the objects for the string. Select this edge as the spine string and choose OK.

1692

Creating a Disc Blend Completing the Blend You need to specify the start and end radii. Key in these values: a Start Value of 3.25, an End Value of 5.00, and choose OK. Toggle off the Confirm Upon Apply option, if needed. Choose Apply. The blend is created. The shaded model looks like this.

Close all part files.

1693

Creating a Conic Blend with Constant Offsets and Constant Rho In this activity, you will create this conic cross-section blend.

Creating a Conic Blend with Constant Offsets and Constant Rho Opening the Part Open part file fff_faceblend_conic.prt from the fff subdirectory, and start the Modeling application. Turn off the display of the WCS.

1694

Creating a Conic Blend with Constant Offsets and Constant Rho Starting the Blend Choose the Face Blend icon

or choose Insert

Feature Operation

Face Blend.

The Face Blend dialog displays. Toggle off the Confirm Upon Apply option. Use the Trim & Attach All Attachment Method.

Creating a Conic Blend with Constant Offsets and Constant Rho Specifying Conic Blend Parameters

The Conic blend type has a conic cross-section, which you can control with two offsets and a rho. All three parameters can be constant or as specified by a law.

Choose the Conic Blend Type. The first and second offsets can be a Constant or Law Controlled blend. Use Constant for both the First and Second Offset. For rho, you have three choices:

1695 Automatic lets the system establish the rho. Law Controlled lets you use the law options. Constant lets you specify a constant value. Use Constant for the Rho option. Both offset values must be positive. Each offset is the minimum distance from the center of the conic blend to one of the face sets. Smaller Rho values create a flatter blend. Key in these values for the conic: a First Offset of 1.0, a Second Offset of 2.0, and a Rho of 0.25. You must use a spine string to define the plane of the conic sections. Choose the Define Spine String option. Select the orange spline at the intersection of the two faces, and choose OK to complete the spine string selection.

Creating a Conic Blend with Constant Offsets and Constant Rho Selecting the First Set of Faces The First Set icon is highlighted on the Face Blend dialog. Select the vertical face as the first sheet, reversing the direction vector if needed so that the vector points toward the left.

Creating a Conic Blend with Constant Offsets and Constant Rho Selecting the Second Set of Faces Now, you can specify the second set of faces.

1696

Choose the Second Set icon. Select the horizontal face as the second set of faces, and reverse the direction vector, if necessary so that the vector points upward.

Creating a Conic Blend with Constant Offsets and Constant Rho Completing the Blend Choose Apply. The conic cross-section blend is created.

Close all part files.

1697

Soft Blend This lesson covers creating Soft Blends, which are more aesthetic and less mechanical than other types of blends.

The cross-sectional shape is not circular, so a mechanical appearance is avoided. This function lets you create designs that are aesthetically pleasing. Also, adjusting the shapes of blends let you produce designs with lower weights, or better stress resistance properties. Several of the options on the Soft Blend dialog are the same as those on the Face Blend dialog.

Creating a Soft Blend In this activity, you will create this soft blend.

1698

Creating a Soft Blend Opening the Part Open part file fff_softblend.prt from the fff subdirectory, and start the Modeling application.

Creating a Soft Blend Starting the Soft Blend Circular blends generally produce shapes that have a hard mechanical appearance, which may be unsuitable for some applications. Soft blends have non-circular cross-sectional shapes. They may be needed for some industrial design applications. It gives you more control over the cross-sectional shape, which may be more aesthetically pleasing, and may be preferred in some styling and industrial design applications.

Choose the Soft Blend icon The Soft Blend dialog displays.

or choose Insert

Feature Operation

Soft Blend.

1699

Creating a Soft Blend Selecting the First Set of Faces To create this feature, you must have two tangency curves and two sets of faces/bodies. This part has a yellow tangency curve on the top face, and a magenta tangency curve on the circular face. The First Set icon is active on the dialog. You will use one circular face for the first set, but the system will let you select more than one face/body. The Filter option lets you mask for All, only Faces, or only Bodies. You need to select the faces and bodies for the first set. Select the circular face as the first set. The direction vector points into the solid body.

1700 This direction will work fine, because the vector should point toward the center of the blend.

If the vector pointed in a direction that was opposite to the desired direction, you would choose Reverse Normal. The Confirm Upon Apply option lets you to view and confirm/reject the feature before you create it. Leave Confirm Upon Apply toggled off. Use the default tolerance of .001 for this model.

Creating a Soft Blend Selecting the Second Set of Faces Choose the Second Set icon. You need to select the second set of faces/bodies. You could select multiple faces/bodies for the second set, but you will use only the top face of the model. Select the top face.

1701

The vector points toward the center of the blend.

Creating a Soft Blend Selecting Tangency Curves You must specify a tangency curve string that lies on the first set of faces/bodies. This string will become the edge of the blend on the first set of faces/bodies, along the point of tangency. Choose the First Tangency Curve icon. The Filter option lets you to select Curves and Edges for the tangency string. Use the Curves filter option. Select the magenta curve on the first face. Now, you need to specify the second tangency curve string. Choose the Second Tangency Curve icon. You will use the yellow curve on the top face. As with the first tangent curve string, you will only select one curve. This string will become the edge of the blend on the second set of faces/bodies along the point of tangency. Use the Curves filter option. Select the yellow curve on the top face.

1702 The Attachment Method options let you control how the blend feature is created. These options are similar to those for Face Blend features. Use the Trim & Attach All option.

Creating a Soft Blend Specifying Attachment, Smoothness, and Rho Match Tangents - matches the adjacent walls in tangency only. Match Curvature - matches both tangency and curvature. For smoothness, choose Match Curvature. Row and Skew Options

The Rho and Skew options are now active, so you can control these shape parameters. A small rho (near zero) will give you a flattened blend. A large rho (near one) will give you a sharply peaked blend. A small skew (near zero) will give a blend with a peak near the first wall selected, and a large value (near one) puts the peak near the second wall. You can think of a soft blend as being composed of an infinite family of cross sectional curves, lying in planes normal to the spine. If you looked at a cross sectional view in a plane normal to the spine, you would see a triangle that is used as a reference when controlling the shape of the blend.

Rho and Skew can be controlled with a Constant value. Or, you can specify that the rho and skew be Law Controlled (controlled by a law).

1703 If you use the Law Controlled option, you will be prompted to specify the law from a dialog of options: Constant, Linear, Cubic, Values Along Spine - Linear, Values Along Spine Cubic, By Equation, or by Law Curve.

Use Constant and .5 for the Rho value. Use Constant and .5 for the Skew value.

Creating a Soft Blend Defining a Spine String You will define a spine string. Choose the Define Spine String option. A dialog of string selection options displays. You can select directly in the view. Choose Solid Edge, select the curved edge as the spine string and choose OK until the model updates.

The feature is created. Shade the view.

1704

Close all part files.

Bounded Plane This lesson covers creating Bounded Planes.

Bounded planes are trimmed planar sheet bodies that are created by using existing outer and inner bounding strings composed of any of the following: solid faces, solid edges, and curves. The strings must be coplanar, and form a closed shape. Outer boundary strings specify the perimeter of the plane. Inner boundary strings specify the holes in the bounded plane.

Creating a Bounded Plane with Holes

1705 In this activity, you will create a bounded plane with two holes, one created from curves, and one created from a sketch.

Creating a Bounded Plane with Holes Opening the Part Open part file fff_bounded_plane.prt from the fff subdirectory, and start the Modeling application. This part contains curves.

Creating a Bounded Plane with Holes Starting the Feature Bounded planes can be created from solid faces, solid edges, and curves.

Choose the Bounded Plane icon Form Feature Bounded Plane.

from the Form Feature toolbar, or choose Insert

You need to select a closed outer boundary string to create the plane.

1706 A dialog displays to assist you in your selection. The string can be composed of solid edges, solid faces, and curves. Since there are only curves in this part, you can select the curves directly on the screen. Select the four curves for the outer boundary string, but do not apply or ok the dialog. The selected objects are highlighted.

Creating a Bounded Plane with Holes Selecting Inner Strings The boundary string dialog continues to display selectable boundary types as you are selecting each object. You can select closed inner boundary strings to create holes in the bounded plane feature. Select the circle as one of the inner boundary strings, but do not apply or ok the dialog, yet. Select the sketch as another inner boundary string.

Creating a Bounded Plane with Holes Completing the Feature

1707 After you have selected all of the objects that define the bounded plane, you can apply, or ok the dialog. Choose OK. The bounded plane is created with two holes. Shade the view.

Close the part file.

Offset Surface This lesson covers creating Offset Surfaces. You can create Offset Surface features at a constant or variable distance from an existing face.

1708

Creating Constant Offset Surface In this activity, you will create an offset sheets from a base face.

Creating Constant Offset Surface Opening the Part Open part file fff_offset.prt from the fff subdirectory, and start the Modeling application. This part contains a sheet body.

1709

Creating Constant Offset Surface Starting the Offset Surface

When you create a constant offset surface, the system must first generate edge curves. The distance tolerance value, on the Modeling Preferences dialog, controls the accuracy of the offset edges. A smaller distance tolerance produces more accurate edge curves. The tolerance value cannot be less than 0.0001 inches, or 0.00254 metric.

Choose the Offset Surface icon

or Insert

Free Form Feature

Offset.

The Offset Surface dialog displays. You can select one or more faces to offset. If multiple faces are selected, they must be sewable. The system will not sew the offsets together automatically. You need to select a face from which to create the offset surface. Select the face of the sheet and choose OK. A vector displays the positive normal direction (downward) for the offset. The system will create the constant offset by projecting points along all the normals of the base face to the specified offset distance(s).

Creating Constant Offset Surface Specifying an Offset Distance and Tolerance

You need to enter a constant Distance to create a constant offset surface, or to choose Variable to create a variable offset surface. If you enter a positive value in the Distance field, the offset surface will be created in the direction of the vector with the constant offset. If you enter a negative value, the offset will occur in the opposite direction. The offset distance cannot be zero. Choose OK to accept the default values of 1 and 0.001.

1710 The offset surface is created.

An unsatisfactory offset body could result if: the base face had curvature reversals (normals that flip-flopped from one side to the other or that go to zero). the offset distance were large enough to produce a self-intersecting offset body.

Creating Constant Offset Surface Creating Another Offset Surface

You can continue creating offset surfaces. Select the newly created offset surface. OK the dialog. Another direction vector displays. Choose OK to accept the default values on the dialog. The second offset surface is created. Fit the view.

1711

Close all part files.

Creating Variable Offset Surfaces In this activity, you will create a variable offset surface.

Creating Variable Offset Surfaces Opening the Part and Starting the Offset Open part file fff_offset.prt from the fff subdirectory, and start the Modeling application. This part contains a sheet body.

1712

You will now create a variable offset surface body.

Choose the Offset Surface icon

or Insert

Free Form Feature

Offset.

You need to select a face to offset. Select the sheet body and OK the dialog. A vector displays the positive direction for the offset. It is located in the center of the sheet. You need to enter an offset distance or choose variable offset. You will be creating a variable offset surface. Choose the Variable option on the dialog. The Point Constructor dialog displays to assist you in point specification.

Creating Variable Offset Surfaces Specifying the Points and Distances

You must select each point and specify the offset location for that point. The points can be any four points on the sheet body. They do not have to be control points. You will select the four corners of the sheet body. Select the front left corner of the sheet.

1713

On the dialog, you need to specify a distance for the first point. You can use the default value. Choose OK to accept the default value of 1.0. Now, you can specify another point for offset. Again, the Point Constructor dialog displays. Select back left corner of the sheet. Two points are marked by the system.

Because this is a variable offset, you can specify a different value for the offset distance for this point. Key in 2.0 in the Distance field and OK the dialog. Again, the Point Constructor dialog displays. Select the front right corner of the sheet, key in 3.0 as the offset distance, and OK the dialog. Select the right back corner of the sheet, key in 4.0 and OK the dialog. The offset surface is created.

1714 Fit the view. Depending on your corner selections, your view may look like this.

An unsatisfactory offset body could result: if the base face had curvature reversals (normals that flip-flopped from one side to the other or that go to zero). if the offset distance were large enough to produce a self-intersecting offset surface. You do not have these conditions in this part, so the offset is smooth. Close the part file.

Bridge This lesson covers the creation of Bridge Surfaces. A Bridge sheet body can be created between two faces with optional side faces or strings. Bridge features can have tangent or curvature continuity with the primary and side faces.

1715

Creating a Curvature Continuous Bridge Between 2 Faces In this activity, you will create a curvature continuous bridge feature between two existing sheets.

Creating a Curvature Continuous Bridge Between 2 Faces Opening the Part Open part file fff_bridge_1.prt from the fff subdirectory, and start the Modeling application. There are two sheets in the part file.

1716

Creating a Curvature Continuous Bridge Between 2 Faces Starting the Feature Choose the Bridge icon

or Insert

Free Form Feature

Bridge.

A Bridge dialog displays.

The four icons at the top of the dialog let you specify the primary faces, side faces, and side strings. The Tangent and Curvature options control the type of continuity for the bridge at the selected faces. The Curvature continuity option lets you create a bridge which follows the curvature between two selected faces. Toggle the Curvature option on. The Primary Faces icon is highlighted, so you can select the primary faces. Selection technique is important, since a twisted shape will result if you select opposing ends. You should select each face near the edge along which you want the bridge to be created, and near the end of the edge that determines the correct direction of the bridge feature.

1717 Select the first face like this.

The direction vector should point upward along the ZC axis.

If you selected near the straight edge, the vector will be pointing toward the left, which will create a twisted shape. If this is the case, you must deselect (shift + MB1) and reselect the face so that the vector points upward.

Creating a Curvature Continuous Bridge Between 2 Faces Completing the Bridge Surface You can continue to select primary faces. Select the next face like this.

1718 Both vectors should point upward.

If the vector points in a direction other than upward, reselect the face, so that the bridge sheet will not be twisted. The Side Faces icon highlights. Side faces are optional. Since you do not have any side faces, you can complete the feature using only two primary faces. Choose Apply to create the sheet.

Creating a Curvature Continuous Bridge Between 2 Faces Using the Drag Function The Drag option lets you to modify the shape of a bridge feature. Choose the Drag option. A Drag Bridge Surface dialog displays. It provides a Reset option to let you reset the feature to its original shape. The bridge feature is created, but you can modify the shape before you cancel the dialog. You will now drag the shape, distorting it by moving the cursor.

1719 Move the cursor onto the bridge surface feature, hold down MB1, slowly move the mouse, and watch the feature change shape.

Vectors will display the direction of change. Try several drags. If you choose OK after you drag the feature, it will maintain the new shape from dragging. Choose Reset on the dialog to restore the original shape. Cancel the dialog. Close the part file.

Creating a Tangent Continuous Bridge Between 2 Faces In this activity, you will create a tangent continuous bridge feature and compare it with a curvature continuous bridge feature.

Creating a Tangent Continuous Bridge Between 2 Faces Opening the Part

1720 Open part file fff_bridge_1a.prt from the fff subdirectory, and start the Modeling application.

You will create a tangent continuous bridge feature between two existing sheets.

Creating a Tangent Continuous Bridge Between 2 Faces Starting the Tangent Bridge Choose the Bridge icon

or Insert

Free Form Feature

Bridge.

A Tangent continuous bridge follows the tangency between the two selected faces. Make sure that the Tangent option is toggled on. You need to select the primary faces. Select this primary face.

The sheet will highlight and a vector will display. Be sure it is pointing upward.

1721

Select the other primary face. Be sure that both vectors point upward. Choose OK to create the sheet.

Creating a Tangent Continuous Bridge Between 2 Faces Comparing the Tangent and Curvature Continuous Bridge Features Make layer 25 Selectable. Fit the view. The curvatures of the two sheets are different.

Analyze the face curvature for each of the sheet bodies.

1722 Close all part files.

Creating another Curvature Continuous Bridge Between 2 Faces In this activity, you will create a curvature continuous bridge feature between two existing sheets.

Creating another Curvature Continuous Bridge Between 2 Faces Opening the Part Open part file fff_bridge_2.prt from the fff subdirectory, and start the Modeling application.

Creating another Curvature Continuous Bridge Between 2 Faces Starting the Feature Choose the Bridge icon The Bridge dialog displays.

or choose Insert

Free Form Feature

Bridge.

1723 Toggle the Curvature option on. You need to select the primary faces. When you select faces next, remember to select them at the same ends. Select the upper face at its lower edge.

Now, you can select the other primary face. Select the lower face at its upper edge.

Creating another Curvature Continuous Bridge Between 2 Faces Completing the Feature The direction vectors should be pointing in the same direction.

1724

Choose Apply to create the bridge feature.

Cancel the dialog. Close all part files.

Creating Several Types of Bridge Features In this activity, you will create five bridge features using this geometry.

The completed model will look like this.

1725

Creating Several Types of Bridge Features Opening the Part Open part file fff_bridge_3.prt from the fff subdirectory, and start the Modeling application.

Creating Several Types of Bridge Features Starting the First Bridge Feature You will create a tangent continuous bridge that follows one side string.

Choose the Bridge icon

, or choose Insert

Free Form Feature

Bridge.

Make sure that the Tangent option is toggled on. You need to select the primary faces. You can only create a bridge between two individual faces. Select the first face like this. Remember, Zoom and Pan as needed to make careful

1726 selections.

The face highlights and a vector displays, and should point like this.

Creating Several Types of Bridge Features Selecting the Second Primary Face Select the second face like this. (Remember to select strings at similar ends to prevent twisted features.)

Make sure that both vectors point in the same general direction.

1727

Creating Several Types of Bridge Features Specifying the First Side String You will use one side string for this bridge feature. Choose the First Side String icon. You need to select the first side string. This part has only one single-segment side string, which is what you will use. Select the side string.

You can now complete the process. Choose Apply on the dialog. The first face is complete. It is tangent to the two other faces and follows the side string.

1728

Creating Several Types of Bridge Features Creating a Second Tangent Bridge You need to select the primary faces. Zoom in on, and select the faces, remembering to check the direction vectors.

You will use the Side Faces option to create a face adjacent to the last one you created. It will be tangent to three faces. If any of the primary or side faces are trimmed, you cannot select only one side object (face or string). If you want to use side objects, you must select two of them. Otherwise, an error message appears. Use Information Object to check that the faces are not trimmed, then close the window and refresh the view. The Side Faces icon is highlighted, so you can select the side faces. You could use more than one side face, but in this part, there is only one side face that you can use. Since the Side Faces option is active, select the edge of the side face like this, and choose Apply on the dialog to complete the selection.

1729

The bridge surface is created.

Creating Several Types of Bridge Features Creating the Bottom Two Bridge Features You can create the same two bridge features on the lower part of the model. Rotate the part, and update the display as needed. Create another tangent continuous bridge feature using one side string at the bottom, like this.

Zoom in on the model for easier selection. Create a tangent continuous bridge feature using one side face at the bottom, like this.

1730

Creating Several Types of Bridge Features Creating a Tangent Bridge Between Primary and Side Faces

Rotate the part to make selection easier. If needed, choose the Bridge icon

or Insert

Free Form Feature

Bridge.

Select the vertically oriented faces as the two primary faces, making sure the vectors point in the same direction. The Side Faces icon just created).

is now active, so select the two side faces (the bridge features you

Choose Apply to complete the bridge sheet.

The shaded model looks like this.

1731 Cancel all dialogs. Close all part files.

Quilt This lesson covers creating Quilt features. A Quilt feature is a single, four sided, bicubic (degree 3x3) approximated B-Surface sheet, that is created from one or more existing faces. A quilt is useful where you need to handle the entire surface as a single, untrimmed, BSurface sheet. It is also useful when a single face will make an operation easier. For example, it might be useful for parameter line machining of a part like this.

Creating a Quilt Using a Mesh of Curves In this activity, you will use primary and cross curves to create a quilt feature.

1732

Creating a Quilt Using a Mesh of Curves Opening the Part Open part file fff_quilt_mesh.prt from the fff subdirectory, and start the Modeling application.

The U and V grid lines are displayed in this part. This unparameterized sheet body has many separate faces. Check the faces in this part file. (Use the Information and Analysis options.) Fit the view.

Creating a Quilt Using a Mesh of Curves Starting the Feature Using a Mesh of Curves Driver Type

Using this model, you will create this single face Quilt feature from the many faces in the current unparameterized feature.

Choose the Quilt icon

or choose Insert

Free Form Feature

Quilt.

The Quilt dialog displays. The Driver Type is used for the projection of points [along vector(s)] from the driver onto the target faces. The system then builds a single quilt approximated B-Surface from these points. Mesh of Curves lets you create a driver from primary and cross curves. The curves must satisfy all of the conditions required for building a curve-mesh B-Surface.

1733

Use the Mesh of Curves driver type. If you used the B-Surface option, the system would use the driver B-Surface that you select. (This part does not have a suitable surface that could be a driver. You will use this option later in this section.) The Self-Refit driver is useful when you want to approximate a lower degree surface from a high degree surface. (You will not use this option; so, refer to the Unigraphics NX online help for more information.)

Creating a Quilt Using a Mesh of Curves Specifying a Projection Type and the Tolerances You must specify a Projection Type. You can think of the projection as a process of emitting a ray from each original point on the driver to the target face(s). The system uses these projected points to construct the BSurface. The direction of the projection of points from the driver surface onto the target surfaces can be a single vector (Along Fixed Vector), or vectors that are normal to the driver face (Along Driver Normals).

1734 Use the Along Fixed Vector projection type. Projection along driver normals is useful if the target surfaces are curved (e.g., cylindrical). The Projection Limit field is grayed out, since it is only used for projection Along Driver Normals. You will use all the default Tolerances. Tight tolerances produce a more complex surface, more patches on the face, a larger file, and slower system performance in down stream operations. Therefore, values should not be any tighter than needed. You might want to use tight tolerances around the edges, and use loose tolerances for the interior (inside) of the approximating surface, thereby allowing a less complex surface.

Creating a Quilt Using a Mesh of Curves Specifying Other Options When the Show Check Points is toggled on, you will see the points as they are calculated during the approximation process, but this will slow down system performance. Displaying points lets you visualize and identify potential problem areas on the surfaces. This lets you troubleshoot and fix problem areas much faster. To improve system performance, toggle Show Check Points to off. Setting Check for Overlaps to off will improve performance, because the system projects the points from the driver onto the first surface that it finds. This is useful when the faces do not actually overlap, or if they are close together in the regions where they do overlap. Be sure that Check for Overlaps is off. If the Check for Overlaps is toggled on, the system projects to all nearby surfaces, and finds the "uppermost" projection points. (Again, refer to the Unigraphics NX online help for more information about checking for overlaps.) OK the dialog. Creating a Quilt Using a Mesh of Curves Specifying Primary Curves

You need to select the primary curves.

1735 Only single curves can be selected as primary curves. You can select from 2 to 50 primary curves. If you need to use a string of curves; you can use Insert, Free Form Feature, Through Curve Mesh to define the driver surface. Each of the primary curves must intersect each of the cross curves only once. They should not be too skewed and must lie on or within the outer boundary of the target faces. Select these two primary curves at similar ends and choose OK.

Creating a Quilt Using a Mesh of Curves Specifying the Cross Curves and Direction Vector Only single curves can be selected for cross curves. You can select from 2 to 50 cross curves. In this part, you will use two curves. Select the top and bottom cross curves at similar ends, and choose OK.

1736 Because you used the projection type Along Fixed Vector, you need to specify a vector direction. The Vector Constructor dialog displays. Choose the ZC Axis icon, and choose OK. A vector displays the direction of the +ZC axis.

The sense of the vector would be most important if you had Overlap Check set to on, because the +ZC vector (pointing in the positive, upward, direction) will approximate the lowest target faces. If the -ZC vector were used the approximation will be based on the highest target faces.

Creating a Quilt Using a Mesh of Curves Specifying the Faces You need to select the target faces that will be used to approximate the quilt. The Class Selection dialog displays. Select all faces in the part. (You can use the Select All option on the dialog, or drag a rectangle around all objects in the view.) Choose OK. Depending on your system, the time to create this feature will vary. Make layers 1 and 2 invisible. Shade the sheet body.

1737

The quilt surface is C1 continuous. In other words, the surface is smooth. This is often an important consideration for manufacturing the part. The system uses the tolerances you defined as it produces the quilt, so it is usually not out of tolerance.

Creating a Quilt Using a Mesh of Curves Editing a Mesh of Curves Quilt Feature The quilt feature is parametric and associative. You can edit the quilt feature and change curves, target faces, projection, and tolerances. Double-click on the quilt feature. The Edit Quilt Surface dialog displays.

1738 The three icons at the top of dialog let you change the primary curves, cross curves, and target faces used to create the quilt feature. To change the projection, you can use options in the middle of the dialog. Also, you can change the tolerances and toggle on the check for overlaps. Cancel the dialog, since you will not be editing the quilt feature. Close all part files.

Creating a Quilt Feature using a B-Surface In this activity, you will create a Quilt using the B-Surface driver type.

Creating a Quilt Feature using a B-Surface Opening the Part Open part file fff_quilt_b_surface.prt from the fff subdirectory, and start the Modeling application. Notice that the eight sheets have small gaps between them. You will be able to create the quilt even though these gaps exist.

1739

Creating a Quilt Feature using a B-Surface Starting the Feature Using a B-Surface Driver You will be using the rectangular sheet as the B-Surface driver.

Choose the Quilt icon

or choose Insert

Free Form Feature

Quilt.

The Quilt Surface dialog displays. Toggle Show Check Points to on. For the Driver Type, choose B-Surface. In some parts, selecting an existing B-Surface as a driver may be easier than selecting the same set of driving curves over and over again. You will use Along Fixed Vector as the projection type. You will also use all the default tolerances. Choose OK. A Select Driver B-Surface dialog displays.

Driver Surfaces

Drive curves should be roughly parallel to major feature lines in the target face. This will make it easier to achieve a close tolerance with fewer patches. However, you have to be careful that the driver curves are not too skewed.

1740 You generally need to check for self-intersections in the driver face. If your driver face is free from self-intersections, then your quilt face will probably be free from them, too. You can also build several quilt surfaces and sew them together.

You need to select the driver B-Surface. Select the driver B-Surface.

You need to select a projection vector. Choose the ZC Axis from the Vector Constructor dialog, and choose OK.

Creating a Quilt Feature using a B-Surface Specifying the Target Faces You need to select the target faces.

Target Faces

Target Surfaces - You should avoid significant steps of more than about 20% of the approximation tolerance in the height of the target faces. The target faces should not contain sharp corners or ridges. However, small mismatches can usually be handled by the system.

1741 Steps may occur where there are extraneous surfaces at different heights from the desired surfaces, or where target surface overlapping occurs, or where surfaces are improperly trimmed.

Target faces should not have back drafts, undercuts, or vertical walls (or nearly so).

You will be using all eight curved sheets as target faces. The Class Selection dialog displays to assist in selection. Select all eight (green) target faces, and choose OK. You will see the system build the construction points as it creates the quilt. Remember, you can abort this process by pressing Control+Shift+L.

1742

The quilt is created.

Cancel the dialog. The quilt is displayed with all the check points displayed. Notice that the construction points are denser near the areas of greater curvature. Close all part files.

Thicken Sheet This lesson covers creating the Thicken Sheet function. The Thicken Sheet icon lets you thicken sheet bodies to create solid features.The thickness is created normal to the faces of the sheet body.

1743

Thickening a Sheet Body In this activity, you will thicken a sheet and unite it to another thickened feature.

Thickening a Sheet Body Opening the Part Open part file fff_thicken_unite.prt from the fff subdirectory, and start the Modeling application.

1744

Thickening a Sheet Body Starting the Feature

Choose the Thicken Sheet icon Form Feature Thicken Sheet.

from the Form Feature toolbar, or choose Insert

The Thicken Sheet dialog displays.

Thickening a Sheet Body Selecting the Sheet Body

The Input Sheet Body thickening.

selection step is highlighted, so you can select the sheet body for

Select the sheet body.

The system displays a vector normal to the sheet body.

1745

Thickening a Sheet Body Specifying an Offset You can thicken a sheet body by using positive and negative First and Second offset values. The thickness is created normal to the selected faces.

Thicken Sheet Offset Values

The system applies positive First Offset and Second Offset values in the same direction as the face(s) normal direction. The system applies negative First Offset and Second Offset values in the direction opposite the face(s) normal direction. The combination of the two offsets must generate a non-zero thickness for a resultant solid body. Examples of ways you can use offset values are shown below.

1746

Use 0.1 as the First Offset. Use 0.0 as the Second Offset. Use the default Tolerance value.

Thickening a Sheet Body Completing the Feature and Uniting Because there is another sheet in the part file, you can choose an Action: Create, Unite, Subtract, or Intersect. Because these two sheets have identical edges, you can only use create or unite. Choose the Unite Action so that the new feature will be united to the existing one.

1747

The Target Solid Body icon is not needed in this activity, and does not become active, unless there is more than one possible target body in the part file. Even then, you would need to select the icon before selecting the target solid body. Choose OK on the dialog. The sheet is thickened and united to the first sheet body.

Close all part files.

1748

Trimmed Sheet This lesson covers creating a Trimmed Sheet.

The Trimmed Sheet option creates a trim by projecting a boundary (edges, curves, faces, datum planes) along a projection direction onto a target sheet body. The result is an associative trimmed sheet body.

Creating a Trimmed Sheet with Two Holes In this activity, you will create two holes in the sheet body, using the Trimmed Sheet option.

1749

Creating a Trimmed Sheet with Two Holes Opening the Part Open part file fff_trimmed_sheet.prt from the fff subdirectory, and start the Modeling application. The sheet body was created with the Through Curve Mesh free form feature function.

You can trim a sheet body using curves, edges, faces, and datum planes.

Creating a Trimmed Sheet with Two Holes Starting the Feature You will use the two closed yellow curves to create two head lamp openings in the hood. The Trimmed Sheet icon boundary.

lets you to modify (trim) the target sheet body to a specified

Choose the Trimmed Sheet icon Sheet. The Trimmed Sheet dialog displays.

or Insert

Free Form Feature

Trimmed

1750

The Confirm Upon Apply option lets you view and confirm/reject the feature before you create it. Toggle off the Confirm Upon Apply option, if needed.

Creating a Trimmed Sheet with Two Holes Selecting the Target Body

The Target Sheet Body you want to trim.

selection step lets you select or deselect the target sheet body that

With the Target Sheet Body

selection step active, select the sheet.

1751

Creating a Trimmed Sheet with Two Holes Specifying the Projection Direction Next, you must specify the projection direction. It is recommend that you choose a Projection Along option after you select the target sheet body (before selecting the trim boundary objects), even though the projection can be specified at anytime. If you project edges/curves along Face Normals the resulting imprinted edge curves will be tolerant edge curves. If you project faces/datum planes along face normals, you can create tolerant or exact (intersection) imprinted edge curves. If you choose Datum Axis, the Projection Vector icon becomes active at the top of the Trimmed Sheet dialog, so that you can select the datum axis. Tolerant or exact imprinted edges can be created when projection is along a datum axis. You can also project along the ZC, YC, or XC Axis, or choose Vector Subfunction to specify a unique projection direction to create tolerant or exact intersection edge geometry. If you change the projection direction after selecting the trim boundary, the system will erase all edges on the target body, which were imprinted by the selected boundary, and will imprint the new edges using the new projection direction. This can take more time. You will be projecting the curves along a direction vector (negative ZC direction) onto the sheet body. Change the Projection Along option to Vector Constructor. The Vector Constructor dialog displays. The negative ZC direction is needed for the system to imprint the curves onto the face.

1752 Choose the ZC Axis icon as the projection axis. Choose Cycle Vector Direction, so that the vector points in the negative ZC direction. Choose OK on the Vector Constructor dialog.

Creating a Trimmed Sheet with Two Holes Specifying the Output Edge Geometry When you perform a trim, you can specify that the imprinted edge geometry be exact or within a tolerance. When Output Exact Geometry is turned on, intersections will be used exactly. However, this will not happen if projection is along face normals, or curves are used for trimming. If curves are used, or projection is along face normals, the Tolerance value will be used.

Imprinted Edges That Result From Trimming Output Exact Geometry Toggled to ON

ON OFF

Projection Along option and trim objects selected

Resulting Imprinted Edges

Any option other than Face Normals, and any trim object(s) other than edges or curves Face Normals and edges/curves

Intersection curve edge geometry - exact imprint

Any projection option and any trimming object(s)

Tolerant curve edge geometry within specified tolerance value Tolerant curve edge geometry within specified tolerance value

You will create edge curves within tolerance first, and then edit the trimmed sheet, changing the output to exact geometry so that intersection curves are developed. First you will create tolerant edge curves (within tolerance). Toggle off the Output Exact Geometry option, if needed. The Tolerance value is important if you want to create tolerant edge curves as an output. The tolerance should be defined before selecting any objects in order to avoid reimprinting of trim boundaries. If you change the tolerance during the trim operation?, the changed tolerance applies the objects you select next. Use the default tolerance value.

1753

Creating a Trimmed Sheet with Two Holes Specifying the Trim Boundaries The Trim Boundary icon lets you select the trimming objects: faces, edges, curves, and datum planes. Choose the Trim Boundary icon. You can filter for Faces, Datum Planes, Curves, and Edges. Select this curve as a trimming object.

A temporary projection vector is created along the -ZC axis of the WCS. This vector is saved at the moment you select one of the WCS axes as the projection direction. If you make any change to the position of the WCS now, it will not affect this vector. For accuracy, you should reselect the projection direction any time you change the WCS.

1754 You can continue to select trimming objects. Select the other closed curve. Both areas are projected (imprinted) onto the sheet body. The "imprinted" areas show where the trim will be made. These trim boundaries will be saved.

Creating a Trimmed Sheet with Two Holes Specifying the Region to Keep The Region icon lets you select the regions to keep or discard. Choose the Region selection step discard.

, so that you can specify the region to keep or

The dialog provides two options: Kept, and Discarded. If Discarded is toggled on, the system discards those areas that you selected. If you use Discarded for this model, then you need to select both projected areas. If Kept is toggled on, the system keeps the area that you selected. If you use Kept for this model, you need to make only one selection. Check that the Kept option is toggled on. Since you have already selected the area of the sheet that you want "kept" (the region is marked with a temporary point, displayed as "+" in the system color), you do not need to reselect it; so, you can simply complete the trim. Choose Apply to complete the trim. The Trimmed Sheet option modifies the target sheet body to the specified boundary and regional conditions. The boundary was used to divide the input sheet body into regions by imprinting new edges on the input sheet body. Cancel the dialog. You have created two holes in the sheet body.

1755

Close all part files.

Enlarge This lesson covers using the Enlarge option to change the size of sheet bodies.

The Enlarge option lets you change the size of an untrimmed sheet, by creating a feature that is associative with the original, overlaid untrimmed face.

Enlarging the Face of a Sheet Body

1756 In this activity, you will use the Enlarge option to modify a sheet body. Notice that on two edges, the sheet will be extended, but on two other edges, the sheet will be reduced.

When creating models using sheets, it is good practice to overbuild them in order to eliminate downstream solid modeling issues. If needed, you can use the Enlarge option to create an enlarged sheet that is associative with the original untrimmed face. Because the Enlarge sheet is parametric and associative, when you edit the original sheet, the enlarge feature will update.

Enlarging the Face of a Sheet Body Opening the Part Open part file fff_enlarge.prt from the fff subdirectory, and start the Modeling application. A sheet body displays in the part file.

Enlarging the Face of a Sheet Body Starting the Feature Choose the Enlarge icon

or Insert

Free Form Feature

Enlarge.

1757 The Enlarge dialog displays. Selecting a face will activate all options on the dialog. You are prompted to select a face to enlarge. Only one face can be selected. Unlike the extension feature, for enlarged features, you can select a trimmed or untrimmed sheet. It can be a parameterized or unparameterized face, and it can be from a sheet body or solid body. Select the sheet body for enlarging. A temporary grid and U/V direction vectors display.

The Reselect Face option lets you select a different face for enlargement. (You cannot use Shift + pick to deselect a selected sheet.)

Enlarging the Face of a Sheet Body Natural Versus Linear Enlargements You can enlarge the face in a Linear or Natural way. Linear extends the edges of the enlarge sheet linearly, in a single direction. Using the Linear Type lets you increase an enlarged feature's size, but you cannot decrease it. Natural extends the edges of the enlarge sheet by following the natural curve of the edges. If you use the Natural Type to size an enlarged feature, you can both increase its size and decrease it. Natural is the default for the Type option. Linear and Natural enlargement types are illustrated below.

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You can use the U-Min, U-Max, V-Min, and V-Max sliders to adjust values, or key in values in the minimum and maximum fields. You can create linear or natural enlargements, and control the U and V directions with minimum and maximum values by keying in specific values, or using the slider bars. The Natural type can contain U-Min and U-Max values that range from -99 to 100. Two examples are shown below. The Linear type can contain U-Min and U-Max values ranging from 0 to 100.

Toggle on the Natural option.

Enlarging the Face of a Sheet Body Using the Natural Type and Enlarging in All Directions On the Enlarge dialog, the All option lets you control all of the U/V-Min/Max sliders as a single group. When this switch is on, all sliders move simultaneously, retaining their existing percentage ratios between each other. Toggle on the All option. Move one of the sliders, and notice that all values change together. Depending the values you use, your image may be different than this.

1759

Notice that you can make the sheet smaller or larger than the original sheet, just as you can with the Isotrim/divide option. Choose Reset to return the sheet to its original shape and size.

Enlarging the Face of a Sheet Body Using the Linear Type You can change the Type between Linear and Natural any time during creation or editing of the enlarge feature. However, doing so resets all values in the U/V-Min/Max fields/sliders to zero. Change the Type to Linear, leave All toggled on, and move a slider to see the change. The Reset option returns the sheet to its original state, after changes have been made, and before the Apply option is used. Choose Reset to return the sheet to its original shape and size.

Enlarging the Face of a Sheet Body Using Natural Type and Enlarging with Specific U and V Values Choose Natural for the type of enlargement. You can key in a specific values, and press the return key on your keyboard to enter a specific value for one of the fields. Key in these values: U-Min of -15, U-Max of 43, V-Min of 21, and V-Max of -16.

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Choose Apply to complete the enlarged sheet. Cancel the Enlarge dialog. Close the part file.

Global Shaping This lesson covers creating Global Shaping features.

Global shaping features are fully associative to the input data provided.

Overcrowning by Function Using the Curve 1 Transition Option

In this activity, you will overcrown the surfaces of a sheet body.

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The Global Shaping option can be used to modify a surface for styling considerations, or to account for the effects of springback during metal forming. You will use the green ellipse to limit the region of modification, to allow for springback during metal forming.

Overcrowning by Function Using the Curve 1 Transition Option Opening the Part Open part file fff_global_shaping_1.prt and start the Modeling application.

You can Blank all curves except the green ellipse, and Refresh the view.

Overcrowning by Function Using the Curve 1 Transition Option Starting the Feature

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The Global Shaping option is useful to deform a surface in a predictable fashion with full associativity of the result. The option can be used for styling, to alter an existing surface while preserving the aesthetic properties, or for manufacturing, to modify a surface to account for the effects of springback during metal forming.

Choose the Global Shaping icon Shaping.

or choose Insert

Free Form Feature

The Global Shaping dialog displays. Leave Confirm Upon Apply turned off.

Overcrowning by Function Using the Curve 1 Transition Option Selecting Faces to Modify You can set the Filter to mask for faces or bodies. Change the Filter option to Face. One or more faces can be selected for overcrowning. You need overcrown the total model, so you need to select all faces on the hood. Select all of the yellow faces of the hood.

Global

1763

Overcrowning by Function Using the Curve 1 Transition Option Selecting the Type and Control Options

The Overcrown controlled by Function method uses a law to shape a new sheet based on a selected face or sheet to be overcrowned, a bounded region, a point in the forming region, and a direction to control the deformation of the new sheet. On the Global Shaping dialog, use Overcrown for the Type. Use Function for the Control by option.

OK the dialog.

Overcrowning by Function Using the Curve 1 Transition Option Specifying the Region Bounds The Overcrown by Function dialog displays.

The cue prompts you to select the boundary of the region that you want modified. The Filter options are available for the selection of a Region Boundary.

1764

The Region Bounds selection step is active on the Overcrown by Function dialog, so you can select the green ellipse to define the limit for the springback compensation. You must select a closed string to restrict the region of modification. Face portions projecting inside the specified boundary are modified and those that fall outside remain unmodified. With the Region Bounds icon

active, select the green ellipse and choose OK.

The Facet Display option, when switched on, shows facets for the temporary display of the new sheet. Toggle on the Facet display to make the new sheet body visible, if it directly overlays the faces selected from the Global Shaping dialog. After selecting a closed boundary and toggling on the Facet display, a representation of the new sheet body displays, based on defaults for the Point in Region and Direction selection steps.

You can continue to dynamically deform the new sheet body by further changing the parameters in the other selection steps. You can now deform the new sheet body.

Overcrowning by Function Using the Curve 1 Transition Option Specifying the Point and Height

1765

When the Point in Region Region Bounds.

selection step is active, you can specify a point inside the

This is an optional selection. This point becomes the highest offset point in the direction specified by the Direction

selection step.

For an ellipse or a rectangle the default is the center. For other closed curves the default it is the center of the bounding box of the curve. The Point Method options can help you specify another point in the region. Height lets you enter a value that is measured against the Point in Region, in the specified Direction. You may use the Height slider bar to dynamically change the height of the projected sheet. A negative value modifies the sheet in the direction opposite to that specified. This model is large, so a small value of one will not make much of a noticeable change in your view. In the Height field, key in a height value of 40 (millimeters) and press the Enter key on your keyboard. The Height slider now displays 40.0 at the center of the slider. The range of the slider is now from 20 to 60.

When you change the point in region from the default, the faceted representation of the new sheet body is immediately updated.

Do not choose OK yet, because you will look at the other options on the dialog before you create the global shaping feature.

1766

Overcrowning by Function Using the Curve 1 Transition Option Specifying the Direction for Modification

The Direction selection step lets you use the Vector Method option menu to specify a direction for the modification. Choose the Direction

selection step.

The default direction displays in the view.

When a planar region boundary is selected, as in this activity, the default direction is normal to the specified boundary. You can use the Vector Method options to change the direction, if needed. When you change the direction from the default, the faceted representation of the new sheet body is immediately updated. If you want to modify the sheet body opposite to the displayed direction, you can enter a negative value for the height. You will use the default direction, which points upward, in the positive direction, normal to the plane of the ellipse. Do not choose OK yet, because you will look at the other options on the dialog before you create the global shaping feature.

Overcrowning by Function Using the Curve 1 Transition Option Shaping the Model The Shape Control slider lets you dynamically change the slope of the law curves.

1767 The range of the slider is from 0.0 through 1.0. The Shape by Function produces an Sshape, with its highest value and zero slope at the center, and decays to zero at the region boundary. The Shape Control slider basically lets you control the speed of decay.

Experiment with the slider, but return it to the .50 location before you continue, otherwise your part will not look like the images displayed here. The Transition Options are based on either two specific functions, named Curve 1 and Curve 2, or is controlled by an equation you setup through the Laws.

Curve 1 function has zero slope at both ends. Curve 2 function has zero slope at t = 0 (corresponding to the center) and nonzero slope at t = 1 (corresponding to the Region Bounds). The Law option lets you define your own transition using Laws and specifying an equation. The value at t = 0 (at the Point in Region) must be one (1) and the value at t = 1 (on the Region Boundary) must be zero (0). Use the Curve 1 icon under the Transition Options heading. You can now create the global shaping feature by choosing OK on the dialog. Choose OK on the Overcrown by Function dialog. Shade and Rotate the view. The overcrown has increased the shape of the top front area of the hood.

1768 Rotate the model to evaluate the two sheets. Close all part files.

Overcrowning by Function Using a Law Transition In this activity, you will overcrown a sheet to look like this, using existing expressions.

Overcrowning by Function Using a Law Transition Opening the Part Open part file fff_global_shaping_2.prt and start the Modeling application. Using Preferences Visualization, choose the Visual tab, and toggle on Silhouettes and OK the dialog, to make the silhouettes visible in the view. The orange sheet displays along with two ellipses. A law curve also displays in the right side of the view.

Overcrowning by Function Using a Law Transition Preparing the View and Checking Existing Expressions Since you will only need to use the green ellipse for this activity, Blank the cyan ellipse,

1769 the orange spline, and the dashed green curves, to simplify your view.

Several expressions have been set up in this part file. Check the expressions by choosing Tools part file.

Expression to view the expressions in this

The expressions t = 0, ft = gt * gt, and gt = 1 + t * t * ( 2 * t - 3 ) will be used to control the overcrowning of the sheet body.

Cancel the Expressions dialog.

Overcrowning by Function Using a Law Transition Starting the Feature Choose the Global Shaping icon Shaping.

or choose Insert

The Global Sharing dialog displays. Check that the Filter option is set to Face. Set the Type options to Overcrown. Set the Control by options to Function. Check that Confirm Upon Apply is toggled off. You need to select one or more faces to be overcrowned.

Free Form Feature

Global

1770 Select the orange sheet body in the view. Choose OK.

Overcrowning by Function Using a Law Transition Selecting Region Bounds The Overcrown by Function dialog displays. The Region Bounds selection step is active. For the region bounds, select the closed green elliptical curve in the view. The temporary overcrowning is visible immediately.

Overcrowning by Function Using a Law Transition Using a Facet Display Toggle on the Facet display option to view the temporary sheet. The facets display in the view.

1771

Choose OK.

Overcrowning by Function Using a Law Transition Using Point in Region and Direction Selection Steps The Point in Region selection step is active. Use the default ellipse center as the Point in Region. Choose the Direction selection step. The direction vector displays in the view. Use the default direction, normal to the plane of the ellipse.

Overcrowning by Function Using a Law Transition Using the Law Equation Transition Option

1772

Choose the Law Transition Options icon.

The Law Controlled dialog displays.

Law Controlled Options

Values Along Spine - Cubic lets you to use two or more points along a spine to define a cubic law function. By Equation lets you define a law using an expression and a "parameter expression variable." This is the option you will use for controlling the transition in this model. By Law Curve lets you select a string of smoothly joined curves to define a law function.

Choose By Equation. The dialog displays t as the parameter expression, which you will use, so choose OK to accept it. (Recall that it was equal to zero in the Expressions dialog.) The dialog displays ft as the function expression, which you will use, so choose OK to accept it.

Overcrowning by Function Using a Law Transition Changing the Height Value Change the Height field to .25 and press the Enter key on your keyboard. The overcrown is reduced significantly. You could dynamically adjust the shape by using the slider.

1773

You do not need to make any changes to the Shape Control. Choose OK on the Overcrown by Function dialog to complete the global shaping feature. Shade the model to view the new feature.

Evaluate the sheets, and then close all part files.

Overcrowning by Function Using a Law Curve

In this activity, you will modify this sheet to look like this, using an existing law curve.

1774

Overcrowning by Function Using a Law Curve Opening the Part Open part file fff_global_shaping_2.prt and start the Modeling application. Make the silhouettes visible in the view. The orange sheet displays along with two ellipses. A law curve also displays in the right side of the view.

Overcrowning by Function Using a Law Curve Starting the Global Shaping You will use the green ellipse for this activity, so Blank the cyan ellipse to simplify your view.

1775

Choose the Global Shaping icon Shaping.

or choose Insert

Free Form Feature

The Global Sharing dialog displays. Check that the Filter option is set to Face. Set the Type options to Overcrown. Set the Control by options to Function. Check that Confirm Upon Apply is toggled off.

Overcrowning by Function Using a Law Curve Selecting the Face and Region Bounds You need to select one or more faces to be overcrowned. Select the orange sheet body in the view. Choose OK. The Overcrown by Function dialog displays. The Region Bounds selection step is active. For the Region Bounds, select the closed green elliptical curve in the view. The temporary overcrowning is visible immediately.

Global

1776

Overcrowning by Function Using a Law Curve Specifying a Facet Display and Direction Toggle on the Facet display option to view the temporary sheet. The facets display in the view. Choose OK. The Point in Region selection step is active. Use the default ellipse center as the Point in Region. Choose the Direction selection step. The direction vector displays in the view. Use the default direction, normal to the plane of the ellipse.

1777

Overcrowning by Function Using a Law Curve Specifying the Law Choose the Law Transition Options icon. The Law Controlled dialog displays. By Law Curve lets you select a string of smoothly joined curves to define a law function. This is the option you will use for controlling the transition in this model. The law curve has been created in this part file. Choose By Law Curve. The dialog provides options for selecting the law curve, but you can select the curve directly. If necessary, zoom in and select the law orange curve at the left end, and choose OK. A direction vector should point to the right. Next, you need to select a base line for use in this activity. Select the lower dashed green line at the left end, so that both direction vectors point to the right.

The Law Controlled dialog provides options to OK the direction or reverse the direction of the base line. Choose OK to accept the direction vectors.

Overcrowning by Function Using a Law Curve Changing the Height Value Fit the view. The temporary global shaping feature reflects the law curve that you selected.

1778

Move the Height slider and watch the changes that take place, then reset the height to 1.0. You do not need to make any changes to the Shape Control. Choose OK on the Overcrown by Function dialog to complete the global shaping feature. Shade the model to view the new feature.

Evaluate the sheets. Close all part files.

Overcrowning Using Base and Control Surfaces In this activity, you will overcrown the front panel using the cyan and orange surfaces. An example of Global Shaping overcrown controlled by surface is shown below. For this method, both base and control sheets are used to modify the original surface.

1779

Overcrowning Using Base and Control Surfaces Opening the Part Open part file fff_global_shaping_5.prt and start the Modeling application.

Rotate it to view the relationships of the various sheet bodies. (This will give you a better understanding of the sheets being used in this part file. Then Restore the view.

Overcrowning Using Base and Control Surfaces Starting the Feature Choose the Global Shaping icon Shaping.

or choose Insert

Free Form Feature

Global

1780 The Global Shaping dialog displays. Check that the Filter option is set to Face. Select all faces of the front panel of the truck. (You can drag a rectangle around all of the faces for easier selection.)

Change the Type to Overcrown. Change the Control by option to Surface. Choose OK.

Overcrowning Using Base and Control Surfaces Specifying the Base Surface The Overcrown by Surface dialog displays. Both a Base surface and a Control surface must be selected to modify the model.

With the Overcrown by Surface method, the overcrown shapes the new sheet against a deformed Base, which is the Control sheet.

1781 These two surfaces have been created for you. However, if you were to create them, the base and control surfaces must be defined so that arbitrary points on the input sheet body may be projected normally to the base surface and produce a single solution. A Base surface must be selected. For the base sheet, select the cyan rectangular sheet in the view and choose OK. Toggle on the Facet display option to see the temporary surface. The temporary blue facet sheet displays.

Overcrowning Using Base and Control Surfaces Specifying the Control Surface

The Control surface selection step is active, so you can select the control surface. The use of a control surface is optional. For the control sheet, select the orange sheet in the view, and choose OK on the Overcrown by Surface dialog. The global shaping feature is created. Rotate it to evaluate the new surfaces in relationship to the original surfaces.

1782

Close all part files.

Stretching by Using Surfaces In this activity, you will stretch a gray body panel so that the surfaces are longer and more streamlined, like this.

Stretching by Using Surfaces Opening the Part First, you want to make sure that file loading options are set correctly, before you open this part file, and start this activity. Choose File Options Load Options and toggle off the Abort Load on Failure option. Then, OK the Load Options dialog. Open part file fff_global_shaping_4.prt and start the Modeling application. The model is the outer surfaces of a snow mobile.

1783

Since you will be working in wireframe mode, turn off Shaded. The view displays many sheet bodies.

Stretching by Using Surfaces Blanking Unused Sheets Since you do not need the upper panels, Blank all aquamarine sheets.

1784

Stretching by Using Surfaces Starting the Feature

Choose the Global Shaping icon Shaping.

or choose Insert

Free Form Feature

Global

The Global Shaping dialog displays. Check that the Filter option is set to Face. Select all grey faces of the body of the snow mobile. Deselect the two green rectangular surfaces in the view, if they are selected. You will use the Stretch by Surface option in the Global Shaping function. Change the Type to Stretch. Change the Control by option to Surface. Choose OK on the Global Shaping dialog.

Stretching by Using Surfaces Selecting Base and Control Surfaces The Stretch by Surface dialog displays. It looks similar to the Overcrown by Surface dialog.

Now, you need to select the Base surface. With the Base icon

active, select the smaller green rectangular sheet in the view.

1785 The Facet display option will display a faceted representation of the sheet bodies as you adjust their shapes. Toggle on the Facet display option. The temporary sheet displays.

Choose the Control icon

, and select the larger sheet as the control sheet.

Stretching by Using Surfaces Completing the Feature Choose OK on the Stretch by Surface dialog. The lower panel is stretched.

Blank both rectangular sheet bodies. Shade the view and compare the newly created (stretched) panel. Notice that the new global shaping feature is longer along the XC axis.

1786

Close all part files.

Stretching by Using a Surface and Moving Poles In this activity, you will stretch the panel so that the surfaces are longer and more streamlined, like this. This time, you will use the Move Poles option on the dialog.

Stretching by Using a Surface and Moving Poles Opening the Part First, you want to make sure that file loading options are set correctly before you open this part file, and start the activity. Choose File Options Load Options and toggle off the Abort Load on Failure option. Then, OK the Load Options dialog. Open part file fff_global_shaping_4.prt and start the Modeling application. The model is the outer surfaces of a snow mobile.

1787

Since you will be working in Wireframe mode, turn off Shaded. Since you do not need the upper panels, Blank all aquamarine sheets. Also, Blank the larger green rectangular sheet body, since you will only need to select one surface to stretch by moving poles.

Stretching by Using a Surface and Moving Poles Starting the Feature

Choose the Global Shaping icon Shaping.

or choose Insert

Free Form Feature

The Global Shaping dialog displays. Check that the Filter option is set to Face. Select all grey faces of the body of the snow mobile. Deselect the green rectangular surface in the view, if it is selected.

Global

1788 You will use the Stretch by Surface option in the Global Shaping function. Change the Type to Stretch. Change the Control by option to Surface. Choose OK on the Global Shaping dialog.

Stretching by Using a Surface and Moving Poles Selecting the Base Surface and Setting Facet Display Now, you need to select the Base surface. Select the green rectangular sheet as the Base surface. The Facet display option will display a faceted representation of the sheet bodies as you adjust their shapes. Toggle on the Facet display option. The temporary sheet displays.

Choose OK to complete the selection.

Stretching by Using a Surface and Moving Poles Using the Move Pole Option The Move Pole icon is active, so you can use it to move a rectangular array of points on the base surface. Choose the Move Pole option on the Stretch by Surface dialog.

1789 The system displays a grid on the base sheet body.

The Move Pole dialog displays.

Stretching by Using a Surface and Moving Poles Specifying a Rectangular Array The Move Pole option is covered in the lesson on editing free form features, but you will use it now to move a rectangular array of poles on the base sheet. You will move poles on the right portion of the base surface. Choose Rectangular Array. The cue prompts you for the first point of the rectangular array. Select this point as the first point of the rectangular array.

1790

The cue prompts you for the second point of the rectangular array. Select this point.

Stretching by Using a Surface and Moving Poles Defining the Drag Vector A direction vector displays in the view.

1791

The direction vector that displays represents the current drag direction, but you will change it using the Move Defining Pole dialog.

The cue prompts you to drag selected points. You can drag along a defined vector or along the face normals. Because you need to drag the poles along the XC direction, you need to redefine the drag vector. Choose Define Drag Vector on the Move Defining Pole dialog. The Vector Constructor dialog displays to assist you in defining the vector.

1792 Choose the XC Axis icon and choose OK on the Vector Constructor dialog. The vectors now point along the XC axis.

Stretching by Using a Surface and Moving Poles Moving the Poles Press and hold MB1 on the right side of the rectangular array of points and drag the points slightly to the right to lengthen the sheets.

As you do this, you will see the temporary faceted display before any updates. The original sheets remain unchanged so far. After stretching the shape slightly, choose OK on the Move Defining Point dialog. The Move Pole dialog redisplays so that you can perform a deviation check, section analysis, import points from a file, or move other points. You could continue to select poles to move.

1793 Choose OK to complete the change and close the Move Pole dialog. The Stretch by Surface dialog redisplays. You could continue to select base and control sheets to control another stretch.

Stretching by Using a Surface and Moving Poles Completing the Model

Choose OK on the Stretch by Surface dialog. The system may require a few minutes to modify the complicated shape of this snow mobile body. The surfaces are stretched. A second rectangular surface has been created by the system.

Blank both rectangular green surfaces. Shade the view.

Evaluate the surfaces of the original and stretched panels. Then Close all part files.

1794

Editing Free Form Features In this lesson, you will use the options on the Edit Free Form Feature toobar.

You will also use the Edit Feature Parameters icon located on the Edit Feature toobar.

Editing the Parameters of a Through Curves Feature In this activity, you will edit the defining curves in this model.

Once completed, the model will update like this.

1795

Editing the Parameters of a Through Curves Feature Opening the Part Open part file fff_edtparam_1.prt from the fff subdirectory, and start the Modeling application. This model is similar to the one you created in the Through Curves lesson.

Editing the Parameters of a Through Curves Feature Using Edit Feature Parameters

Edit Feature Parameters option

lets you modify the creation parameters of smart features.

Changes to the curves or expressions used to create the body will update the model. In this part file, you will change a radius of an arc and update the model. You can double-click on the sheet body to edit its parameters. Double-click on the sheet body in the view. The Edit Parameters dialog displays options for editing the through curves feature: Tolerance, Edit Curve, Edit V Degree, Add String, Remove String, Respecify Starting Curve, Edit Alignment, and Display Parameters. Depending on the feature you select, different options display in this dialog. The Display Parameters option lets you view the current number of sections, guides, and spine, view the starting direction of the section strings, and view alignment points, if any exist. Choose Display Parameters. The section string labels display in the order of their use. Direction vectors also display. These show you how the section strings were selected to create the feature.

1796 The Tolerance option lets you enter in a new distance tolerance for Swept, Through Curve, and Ruled free form features, or intersection tolerance for Through Curve Mesh free form features. You can change an "approximate fit" face or feature to an exact fit by changing the distance tolerance to 0.0. This may help you with downstream applications, such as blend, hollow, Boolean operations, etc. Choose the Tolerance option. A dialog displays the current tolerance. To change the tolerance that was used in this model, you can change the value in the Tolerance field and choose OK three times. Choose Back to return to the list of parameters that you can edit. The Edit V Degree option lets you change the V degree for a Through Curves feature. Choose Edit V Degree. The V degree of 3 was used in the creation of this feature. You can change the degree of the feature and choose OK three times to complete the change. Choose Back to return to the list. The Edit Alignment option lets you respecify the alignment method used in the feature. Depending on the exact construction/edits of the desired feature, not all the alignment method options may be displayed. Choose Edit Alignment. The list of alignment methods displays. This feature was created using Parameter alignment. Only arclength and parameter are available for this part, so only these two options display. You could change the alignment now, but do not do so. Choose Back. Refresh the view, if needed.

Editing the Parameters of a Through Curves Feature Editing the Defining Curves

1797 The Add String option lets you add existing strings to the geometry of the body. When adding strings to a curve mesh body, strings of the same type (e.g., primary strings) cannot have coincidental endpoints. The Remove String option lets you remove strings from a body. A body must have at least three strings in its construction to be able to remove a string. The Respecify Starting Curve option lets you respecify the starting curve or direction of the string. The Edit Curve option lets you edit one of the curves that was used to create the feature. The section strings in the model are composed of single arcs. It lets you modify existing curves/segments of a string using the same options located under Edit, Curve. Choose Edit Curve. The Edit Curve dialog displays. The Edit Curve Parameters icon is highlighted. Notice that the bottom of the graphics window displays fields for the values of XC, YC, and ZC.

You can edit any of the five defining curves, which are the arcs in this part. Select the middle arc.

The arc radius is currently 6.00 inches. You can change it, or change the diameter. Change the Radius value to 4.0 and press the Enter key on your keyboard.

1798

Editing the Parameters of a Through Curves Feature Completing the Change The curve is displayed smaller in the view.

You could continue to edit as many strings as required. You will not edit any other curve in this model. Choose Apply on the Edit Curve dialog, then OK the dialogs until the model updates. Refresh the view.

Close all part files.

Replacing a Defining Curve of a Swept Feature In this activity, you will edit the defining curve of a free form feature and change its shape to look like this.

1799

Replacing a Defining Curve of a Swept Feature Opening the Part Open the part file fff_edtparam_2.prt from the fff subdirectory, and start the Modeling application. The sheet was created with two strings of defining curves. Shade the sheet body to see its shape and then return to a wireframe display.

A magenta spline displays near the bottom of the sheet. You will replace the existing bottom string with the magenta spline string.

Replacing a Defining Curve of a Swept Feature Removing an Original Defining Curve

1800 Double-click on the sheet body to edit it. The Edit Parameters dialog displays for this feature.

The dialog varies, depending on the feature that you edit. Notice that you can directly edit both the distance and angle tolerance in this dialog. You will replace the defining curves of the feature. Choose Replace Defining Curves. Replacement options display on the dialog. As with the prior dialog, this dialog also varies depending on the feature selected.

You can now begin to replace the lower defining curve. Choose Replace Generator Curve. Watch the direction vectors as you do your work. These two direction vectors of the existing body display.

1801

Replacing a Defining Curve of a Swept Feature Selecting Another Generator Curve You need to select the curve to be replaced. Select the curve located at the bottom of the sheet body. Remember, you can use Undo if you are not satisfied with the results. You need to select the curve to be inserted. Select the curve (magenta) to be inserted, making sure to select near the same corner that the other curve was selected.

On the Confirmation dialog that displays, choose OK.

1802

Replacing a Defining Curve of a Swept Feature Completing the Update Choose OK on the list of edit feature options. The direction vectors change to reflect the newly inserted curve. Choose OK until the model updates. The sheet now uses the magenta curve for the definition of the sheet body. The shaded model looks like this.

Close all part files.

Moving Defining Points In this activity, you will move defining points in a feature in order to create a deeper bowl.

1803

Moving Defining Points Opening the Part Open part file fff_movepoint_1.prt from the fff subdirectory, and start the Modeling application.

Moving Defining Points Setting up the Part File In addition to the solid model, curves are on layer 41, and a sheet body is on layer 81. You will edit the section surface feature by moving defining points of the sheet body, making the bowl deeper. Make layer 81 selectable, which contains the section surface sheet body.

1804 Again, rotate the model to check the features that display. Make the Edit Free Form Feature toolbar visible, if it is not.

Moving Defining Points Using Move Defining Point

The Move Defining Point

option lets you move the defining points on the body.

Choose the Move Defining Point icon Defining Point.

or Edit

Free Form Feature

Move

The Move Defining Point dialog displays.

Moving Defining Points Editing the Sheet You can edit the original sheet, or a copy of the sheet. By editing a copy, you can keep the creation parameters of the original sheet. Choose Edit Original Sheet. Select the sheet body.

1805

Because the sheet body is a parameterized feature, you will receive a warning message. Choose OK on the Confirmation message to continue to edit the sheet body.

This edit will result in an unparameterized feature.

Moving Defining Points Using the Move Point Options The Move Point dialog displays options for moving a single point, a row of points, a column of points, or a rectangular array of points.

1806

Move Point Options

Single Point lets you specify a single point to move. This is the default option. Entire Row lets you move all points in the same row (constant V). To move the row, select a point in the row you want to move. Entire Column lets you move all points in the same column (constant U). To move the column, select a point in the column you want to move. Rectangular Array lets you move the points contained in a rectangular area. To move the area, select two opposite corner points of the rectangle you want to move. Redisplay Surface Points lets you redisplay those points which are eligible for selection. This is useful if you refresh the view and need to redisplay the points. Points From File lets you import an ASCII text file (*.dat) of point data. This is useful if you want to use point data stored in another file, which could have been created from computer generated points, machine generated points, or from other sources.

This sheet body was created with curves, not points, so the points that display are "system created" defining points located on the face of the sheet body. The cyan sheet body is temporarily blanked by the system to make point selection easier; however, the thicken feature is displayed in white.

1807

Moving Defining Points Selecting the First Point for the Rectangular Array of Points You will move a rectangular array of points. Toggle on the Rectangular Array. Now, you need to select the first point of the rectangular array. For the first point of the rectangular array, select the point located at the top of the second to the left column of points.

The system creates a marker on the point that you select.

Moving Defining Points Selecting the Last Point for the Rectangular Array Now, you need to select the other point to define the other end of the rectangular array. Select the third point located on the bottom row of points.

1808

The rectangular array of points are marked by the system. Notice that they are the two rows of points located in the central portion of the bowl.

You can use Reselect Points if you are not satisfied with the selected points.

Moving Defining Points Specifying an Offset A Move Defining Point dialog displays.

Move Defining Point Options

1809

You can move the selected point by a Delta (difference) or Distance Along Normal. You can also choose to move the selected point to a point, define a drag vector or reselect points to move. Delta lets you specify a delta offset by which to move the point. Distance Along Normal lets you move the point a specified distance along the face normal at that point. When you choose this option, a direction vector will display that represents the normal. You can enter a positive or negative distance value. Move to a Point lets you use the Point Subfunction to specify a point to move the selected point to. This option is only available when you select Single Point. Define Drag Vector lets you define a vector that is used for the Drag option. Reselect Points returns you to the Move Point Selection dialog.

You will be specifying a distance using the DYC field. Key in a DYC value of -10 and choose Apply. The modified copy of the sheet body is temporarily created and displayed. Notice that you have created a deeper scoop.

If you cancel the dialog, this new shape will be removed. If you are unhappy with the change, you can choose Reselect Points and then respecify points, but you will accept the new shape.

1810

Moving Defining Points Completing the Model Choose OK on the Move Defining Point dialog. Choose OK on the Move Point dialog to complete the sheet body. Since the function is modal you can continue to move points. Cancel the Move Defining Point dialog, and Refresh the view. The thicken feature updates based on the edits you made to the shape of the sheet body.

Make layer 81 Invisible, so that the sheet body no longer displays. Rotate and check the model. Close all part files.

Moving Poles In this activity, you will move poles to lengthen the shape of the spoon, so that it looks like this.

1811

Moving Poles Opening the Part Open part file fff_movepole_1.prt from the fff subdirectory, and start the Modeling application.

Make layer 81 selectable, which contains the section surface sheet body.

Moving Poles Starting to Move Poles

1812 Move Pole option lets you move poles of the body.

Choose the Move Pole icon

or Edit

Free Form Feature

Move Pole.

The Move Pole dialog displays.

You can edit the original sheet, or a copy of the sheet. By editing a copy, you can keep the creation parameters of the original sheet. Choose Edit Original Sheet.

Moving Poles Selecting the Sheet Body Because the sheet body is a parameterized feature, you will receive a warning message. Select the sheet body.

Choose OK to continue to edit the sheet body, which will result in an unparameterized feature.

1813

Moving Poles Moving Poles A control polygon displays around the body. The sheet body is blanked, and the thicken feature is displayed in white. Unlike defining points, control points are usually not on the sheet body.

A Move Pole dialog displays.

Move Pole Options

Single Pole lets you specify a single pole to move. This is the default option. Entire Row lets you move all poles in the same row (constant V). To move the row, select a point in the row you want to move.

1814 Entire Column lets you move all poles in the same column (constant U). To move the column, select a point in the column you want to move. Rectangular Array lets you move the points contained in a rectangular area. To move the area, select two opposite corner points of the rectangle you want to move. Deviation Check lets you specify options from the Deviation Check dialog. This option is described later in this lesson. Section Analysis lets you specify options from the Section Analysis dialog. This option is described later in this lesson. Points From File lets you import an ASCII text file (*.dat) of point data. This is useful if you want to use point data stored in another file, which could have been created from computer generated points, machine generated points, or from other sources.

Moving Poles Selecting a Row Notice the U and V directions that display on the model. You will be moving the bottom row downward along the V direction, to create a longer scoop. Choose Entire Row (constant v). The system prompts you to select a pole to move. You need to select a pole on the desired row that you want to move. Select the left point in the bottom row.

1815 The entire bottom row of poles are marked by the system, and a direction vector points in the positive ZC direction. A Move Defining Pole dialog displays.

Moving Poles Specifying a Vector You can move defining poles using Along Defined Vector, or Along Normals. You will move the bottom row of poles in a negative ZC direction, so that the scoop has a more tapered end. Use Along Defined Vector. You will move the row of points in a negative -10 units, so that the sheet body will become longer near the scooping edge. Use all other default options. In the DZC field, key in -10 and choose OK. The control polygon changes, as does the temporary sheet body.

1816

Moving Poles Editing During an Update The Move Pole dialog redisplays.You need to OK the dialog or you will lose the changes. OK the Move Pole dialog. Cancel on the Move Pole dialog. The Edit During Update dialog indicates that the blend radius is too large.

Choose the Edit icon

on the dialog.

Another Edit During Update dialog displays.

Choose the Edit Parameter icon

on the dialog.

Change the Radius to 15 and press Enter on the keyboard, and OK the change. The Edit During Update dialog displays again.

1817 OK the Edit During Update dialog to update the model.

Moving Poles Checking the Model The model updates.

Make layer 81 Invisible so that the sheet body no longer displays. Rotate the model so that you can see the changes to the shape of the scoop. Notice that the model has updated.

Close all part files.

1818

Dividing a Sheet Body by Using Isoparametric Trim/Divide In this activity, you will use the Iso Trim/Divide options to divide the sheet body.

Dividing a Sheet Body by Using Isoparametric Trim/Divide Opening the Part Open file fff_isotrim_1.prt from the fff subdirectory, and start the Modeling application.

Dividing a Sheet Body by Using Isoparametric Trim/Divide Using Isoparametric Divide

Isoparametric Trim/Divide lets you trim or divide a body in either the U or V isoparametric direction at a specified parameter. This function creates a non-associative sheet body. If you need an associative sheet body, you may want to use the Enlarge free form feature option.

Choose the Isoparametric Trim/Divide icon Isoparametric Trim/Divide.

or Edit

A dialog displays options to trim or divide the body.

Free Form Feature

1819

You will be dividing the body, so you need to choose the appropriate option. Choose Isoparametric Divide to divide the body. Dividing a Sheet Body by Using Isoparametric Trim/Divide Selecting the Face

As with other editing options, you can edit a copy or the original sheet. Use Edit Original Sheet. When you edit the original body, it cannot be untrimmed. The original body definition is lost. But, you can use Undo immediately after the edit. You need to select a face. Select the sheet body. A message displays, warning you that the operation removes parameters. If you choose OK, all parameters will be lost. If you choose Cancel, the modification will not be made and parameters will remain.

Choose OK on the message to complete the change, and remove parameters.

Dividing a Sheet Body by Using Isoparametric Trim/Divide Specifying the Parameters The U and V direction vectors display on the body.

1820

The Isoparametric Divide dialog displays.

The Constant U, and Constant V options let you divide the body in either the U or V isoparametric direction. You will divide the sheet in the V direction, along the U isoparametric line. Toggle the Constant V option on. The Percentages Division Value controls the division of the body. You will use the default value.

Dividing a Sheet Body by Using Isoparametric Trim/Divide Completing the Isoparametric Divide Choose OK to accept the value of 50 percent. The sheet is divided in half in the V direction (along the U isoparametric line) and two new U, V direction vectors display, one for each new sheet body. This is an unparameterized feature.

1821

Although the body cannot be untrimmed, and the original body definition is lost, you can use Undo immediately after the edit. After trimming a face of a multi-face sheet, the system attempts to sew the sheet together. In certain cases, where the trim has created a gap in the sheet, the sewing operation will fail, and the trim will not be completed. Close the part file.

Trimming a Sheet Body by Using the Isoparametric Trim/Divide Option In this activity, you will use the Isoparametric Trim option to expand the sheet in one direction and narrow the sheet in the other direction, like this.

Trimming a Sheet Body by Using the Isoparametric Trim/Divide Option Opening the Part Open file fff_isotrim_1.prt from the fff subdirectory, and start the Modeling application. You will trim this sheet body.

1822

Trimming a Sheet Body by Using the Isoparametric Trim/Divide Option Using Isoparametric Trim Choose the Isoparametric Trim/Divide icon Isoparametric Trim/Divide.

or Edit

Free Form Feature

The Trim/Divide dialog displays options to isoparametrically trim or divide the body. You will be trimming the body. Choose Isoparametric Trim. You can edit the original sheet or edit a copy of the sheet.

Trimming a Sheet Body by Using the Isoparametric Trim/Divide Option Selecting the Face You will edit a copy of the sheet. Choose Edit a Copy. You need to select the face to be trimmed. Select the sheet body. You are editing a non-associative copy of the sheet body, so you will not receive a message that the parameters will be removed from the base feature. Notice the U and V direction vectors that display.

Trimming a Sheet Body by Using the Isoparametric Trim/Divide Option Specifying the U Min and Max Values

1823

The Isoparametric Trim dialog displays.

Specifying Isoparametric Trim U Min and Max Values

U-Min(%) lets you specify a minimum parameter percentage value in the U sheet body direction. U-Max(%) lets you specify a maximum parameter percentage value in the U sheet body direction. Parameters can be any positive or negative value. Any of the four values can be less than 0.0%, greater than 100.0%, or between 0.0% and 100.0%. Use Diagonal Points lets you define your parameters using two view points or Point Constructor. The two points indicate the corners of a U-V rectangle which determines the extents of your new face. .

You will use the minimum/maximum fields. You must use a Minimum percent that is smaller than the Maximum percent, for the U and V direction. Change the U percentages as follows: U-Min (%) value of 5 , U-Max (%) value of 75, and choose OK. The new copy is shortened in the U direction.

1824

Two sets of vectors display, one for each sheet.

Trimming a Sheet Body by Using the Isoparametric Trim/Divide Option Specifying the U Min and Max Values The copy of the original sheet remains selected so that you can continue trimming operations on this sheet.

Specifying Isoparametric Trim V Min and Max Values

V-Min(%) lets you specify a minimum parameter percentage value in the V sheet body direction. V-Max(%) lets you specify a maximum parameter percentage value in the V sheet body direction. Parameters can be any positive or negative value. Any of the four values can be less than 0.0%, greater than 100.0%, or between 0.0% and 100.0%. Use Diagonal Points lets you define your parameters using two view points or Point Constructor. The two points indicate the corners of a U-V rectangle which determines the extents of your new face.

Change the V percentages as follows: V-Min (% ) value of -100, and V-Max (%) value of 400, and choose OK. The sheet is changed in the positive and negative V directions. Fit and Refresh the view. The sheet is now extended in the negative and positive V directions.

1825

Cancel all dialogs. Close all part files.

Increasing the Degree of a Sheet Body In this activity, you will increase the degree of a copy of this sheet body.

About Change Degree

Change Degree lets you change the degree of a body. Decreasing the degree of a body lowers the degree while attempting to preserve the overall shape and character of the body.

1826 You can decrease the degree for single patch bodies. If you increase degree and decrease it later, the resultant body will be the same as when you started. If you are dissatisfied with the change, you can always reject it and revert to the previous body. Increasing the degree of a body using this function does not change the shape of the body, but does increase its number of poles that are available to you for editing the body.

Increasing the Degree of a Sheet Body Opening the Part Open part file fff_chngdegree_1.prt from the fff subdirectory, and start the Modeling application. This part is similar to one you created in the lesson on From Poles. The part was created using From Poles, with multiple patches, and a U and V degree of 3.

Use the Information Object to check the U and V degree of the sheet body. (Notice that the degree is 3 for both U and V.) Increasing the Degree of a Sheet Body Changing the Degree

Choose the Change Degree icon

or Edit

Free Form Feature

You can edit the original sheet or edit a non-associative copy of the sheet.

Degree.

1827 Choose Edit Original.

Increasing the Degree of a Sheet Body Selecting the Face Select the sheet. The dialog now displays U Degree and V Degree parameters.

The U and V direction vectors display in the graphics window.

1828

Increasing the Degree of a Sheet Body Decreasing and Increasing the Degree Multiple patch bodies, like this one, and closed bodies, can only have their degree increased. You must use integers between 1 and 24. Increase the U Degree value to 4, and a V Degree of 7, and choose OK. Cancel the dialog and Refresh the view. The sheet looks exactly the same, but it has a new U and V degree.

Use the Information Object to check the U and V degree of the sheet body. (The new values of 4 and 7 will display in the Information window.) Close all part files.

Increasing the Stiffness of a Sheet Body In this activity, you will change the stiffness of a sheet body, which results in a modified shape.

1829

About Change Stiffness

Change Stiffness lets you modify the shape of the body by changing its degree. Change Stiffness contrasts with the Change Degree, which produces a new body with the same shape, different poles, and the same number of patches as the original underlying surface. Decreasing the degree reduces the "stiffness" of the underlying surface and allows it to mimic the undulations (reversals of curvature) of its control polygon more closely. Increasing the degree makes the surface "stiffer" and less sensitive to undulations in its control polygon. If you increase the degree, the new body will have the same poles as the original, but will have a different (stiffer) shape and fewer patches. The minimum degree allowed is 2; the maximum degree is equal to one less than the number of poles defining the underlying surface in that direction, up to a degree of 24. You must use integers.

.

Increasing the Stiffness of a Sheet Body Opening the Part Open part file fff_chngstiff_1.prt from the fff subdirectory, and start the Modeling application.

1830 This part is similar to one you created in the lesson on From Poles.

The part was created using From Poles, with multiple patches, and a U and V degree of 3.

Increasing the Stiffness of a Sheet Body Editing the Stiffness You will increase the degree of a copy of this sheet body.

Choose the Change Stiffness icon

or Edit

You can edit a copy, or the original sheet.

You will edit a copy of the sheet body. Choose Edit a Copy.

Free Form Feature

Stiffness.

1831

Increasing the Stiffness of a Sheet Body Selecting the Face You need to select a face to edit. Select the sheet. The U and V direction vectors display on the part.

Increasing the Stiffness of a Sheet Body Changing the Stiffness The Change Stiffness dialog displays the current U and V degrees.

Multiple patch bodies (like this one) and closed bodies can only have their degree increased. You will be increasing the degree, thus making the surface smoother (stiffer).

1832 Change the U Degree value to 4.0, and a V Degree of 7, and choose OK. Cancel the dialog. To remove the display of points, make layer 1 Invisible and Refresh the view.

Editing the stiffness of the sheet changes the sheet body. In this case, the model is stiffer. You can check this out by using the Information options. Choose Information

Object, Type, Face, OK, Select All, and choose OK.

The Information window displays the information about both B-Surface sheet bodies. Review the information in the window, and close the window. Close all part files.

Matching Edges and Cross Tangents of Two Sheet Bodies In this activity, you will change the edge of one sheet body to match the edge of another (adjacent) sheet body, like this.

1833

Change Edge lets you perform edge matching by modifying an edge to coincide with a curve, or an edge of another body, or to lie in a plane. You can also modify the normals or cross tangents at the edge by various methods.

Matching Edges and Cross Tangents of Two Sheet Bodies Opening the Part Open part file fff_matchedge_1.prt from the fff subdirectory, and start the Modeling application. There are two sheet bodies in this part file.

Change the work layer to layer 2.

1834

Matching Edges and Cross Tangents of Two Sheet Bodies Changing the Edge You will change (match) the straight edge to the curved edge and make the new sheet body tangent to the other sheet body.

Choose the Change Edge icon

or Edit

Free Form Feature

Change Edge.

Matching Edges and Cross Tangents of Two Sheet Bodies Selecting the First Face The Change Edge dialog displays. You will edit a copy of the sheet body. Choose Edit a Copy. Since you will match the lower face to the upper face, you need to select the lower face first. Select the lower cyan sheet body.

1835

Matching Edges and Cross Tangents of Two Sheet Bodies Selecting the Edge of the First Face

You need to select the B-Surface edge to edit. The edge of the first sheet (lower sheet) that you selected will change to match the edge of the second sheet that you will select. The edge of the first sheet cannot be longer than the edge of the second. You cannot select a trimmed sheet, or a sheet without edges, for modification. The edge to be matched must be an original isoparametric edge, rather than one produced by trimming. In this part the edge ends are at the same locations. The edge that you select will be change to meet the next sheet edge that you designate. Select the top edge of the lower sheet.

1836

Matching Edges and Cross Tangents of Two Sheet Bodies Specifying the Change Edge Options

A dialog displays options available for changing edges. Edge & Cross Tangents lets you match a selected edge and/or its cross tangents to various entities. Edge cross tangents are the tangents of the isoparametric curves at their endpoints, where they meet the edge. Refer to the Unigraphics NX online help for more information about all other options. Since you will want the two sheets tangent and matched, you will use this option. Choose Edge & Cross Tangents. The dialog displays several options.

Change Edge Options

Aim at Point deforms the body so that the cross tangent at every point along the selected edge passes through a specified point. This makes the body assume the shape of a generalized cone along the selected edge, although the shape of the edge itself is unchanged. Match to Vector deforms the body so that the cross tangent at every point along the selected edge becomes parallel to a specified vector. This makes the body assume the shape of a generalized cylinder along the selected edge. The shape of the edge itself is unchanged.

1837 Match to Edge will deform the body, so that the first selected edge matches the second selected edge, in position and normals, creating a smooth blend between the two bodies. The edge on the second body must be an original (isoparametric) edge, not one that was produced by trimming. If the body to be edited is linear in a direction perpendicular to the edge whose position and cross tangents are to be matched to the second body, you should raise the degree of the first body along the linear direction in order to maintain smooth flow lines.

Matching one edge to another edge gives you the congruency necessary to create a sewn solid. Choose Match to Edge.

Matching Edges and Cross Tangents of Two Sheet Bodies Selecting the Second Face You need to select the second face and edge to be matched. Select the upper body.

Matching Edges and Cross Tangents of Two Sheet Bodies Selecting the Second Edge Select its edge.

1838

The edges are matched.

Matching Edges and Cross Tangents of Two Sheet Bodies Checking the Model Cancel the dialog. Blank the original lower sheet body. The model looks like this, if shaded.

1839

At this point you could sew the two sheets together into one sheet body. The new sheet body is unparameterized. Close all part files.

Trimming the Edges of a Fillet Using the Sheet Boundary Option In this activity, you will use the Sheet Boundary icon to trim the fillet sheet body.

1840

Trimming the Edges of a Fillet Using the Sheet Boundary Option Opening the Part Open part file fff_sheetboundary_1.prt from the fff subdirectory, and start the Modeling application. The part is similar to one you created in the Fillet lesson.

Trimming the Edges of a Fillet Using the Sheet Boundary Option Using the Sheet Boundary Option

Sheet Boundary

lets you modify or replace an existing boundary of a sheet body.

You can remove a trim or individual holes from a sheet body or extend the boundaries if the sheet is a single face sheet body.

Choose the Sheet Boundary icon

or Edit

Free Form Feature

Boundary.

The Edit Sheet Boundary dialog displays. You will be editing the original sheet. Choose Edit Original Sheet. You need to select the sheet body that you want modified.

Trimming the Edges of a Fillet Using the Sheet Boundary Option Selecting the Sheet and Trim Option You will be trimming the white fillet sheet body. Select the fillet sheet.

1841

Trim options displays in the dialog.

Edit Sheet Boundary Options

Remove Hole lets you remove a hole from a sheet body. When Edit A Copy is used with this option, the hole will be removed from the copy, maintaining the original sheet with the hole. Remove Trim lets you remove trims performed on a sheet body and restore the body to a parametrically rectangular form. When Edit A Copy is used with this option, the trim will be removed from a copy of the trimmed sheet body, maintaining the trimmed sheet. You can use Edit, Feature, Delete Feature to remove a trimmed sheet feature. Replace Edge lets you replace single or connected edges of a sheet body with new edges that lie inside or outside the current ones. This works on single face sheet bodies only.

You will replace the edge of the fillet by specifying a plane. Choose Replace Edge.

Trimming the Edges of a Fillet Using the Sheet Boundary Option Selecting the Edge to Trim The Class Selection dialog displays. You need to select the edges that you want replaced. You will be replacing the edge at the right end of the fillet sheet body.

1842 Select the right edge of the sheet body and choose OK.

Trimming the Edges of a Fillet Using the Sheet Boundary Option Specifying the Trim Boundary A dialog displays options for specifying a new trim boundary.

Edit Sheet Boundary Trim Options

Select Faces lets you select faces of an existing body (solid or sheet) as bounding entities. Specify Plane lets you use the Plane Subfunction to specify planes as part of the boundary. Curves Along Normal lets you select curves and edges that are projected onto the base sheet along its normals. Edge curves of the base sheet are automatically included and need not be selected as part of the boundary for trimming. Curves Along Vector lets you select curves and edges that are projected onto the base sheet along a direction vector that you specify using the Vector Constructor.

1843 Specify Projection Vector lets you specify the direction that curves along vector are projected. You can change the direction vector as additional curves are selected. You need to specify a trim option. Choose Specify Plane. The Plane dialog displays. Refer to the Unigraphics NX online help for details on all options on the dialog. You will be specifying a plane using three points. Choose Three Points. Select these three endpoints.

A plane symbol displays that passes through the three selected points. The location will be determined by your selections.

Trimming the Edges of a Fillet Using the Sheet Boundary Option Indicating the Portion to Keep Choose OK on the dialog of the five trim options. The Class Selection dialog displays. Choose OK on the Class Selection dialog. You must indicate the portion that you want to keep. You will keep the fillet that is tangent to the two sheet bodies.

1844 Select the fillet sheet body.

Trimming the Edges of a Fillet Using the Sheet Boundary Option The Trimmed Fillet Choose OK to complete the edit. The fillet sheet body is trimmed. Cancel the dialog.

This trimmed sheet is an unparameterized feature, so you cannot edit its parameters. Close all part files.

1845

Reversing Surface Normals In this activity, you will reverse the normals for the following model.

The Reverse Normal option lets you create a parametric feature with a reversed normal. The Reverse Normal feature is useful to prevent update problems due to trimming operations using sheets, and in controlling the display during shading, especially if you are using third party shading tools.

Reversing Surface Normals Opening the Part Open part file fff_faceblend_3.prt from the fff subdirectory, and start the Modeling application.

1846

Reversing Surface Normals Reversing Normals of Sheets Choose the Reverse Normal icon

or Edit

Free Form Feature

Reverse Normal.

The Reverse Normal dialog displays. You need to select the sheet bodies that you want to reverse. One or more sheets can be selected. Select the middle and lower sheets, so that the vectors display like this.

Reversing Surface Normals Completing the Reversal of Normals The Reverse Normal dialog options are active as soon as one sheet is selected.

If (through refresh or other function) the normal is not displayed, the Display Normal option will show it for you. If any of the sheet bodies selected for reversal already contain reverse normal feature(s), those bodies will not be highlighted and a dialog like this will display. There is no limit to the number of reverse normal features that you can apply to a sheet body.

1847

Choose OK (or Apply) to reverse the direction vector. The reverse normal feature is created. As with other features, you can suppress, reorder, delete, and find information on the reverse normal feature. However, you cannot transform a reverse normal feature. You cannot use Edit Parameters on this feature. Close all part files.