ESPRIT Milling Tutorial 02

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Mill on a Rotary Axis  ESPRIT’s 4-axis wrap milling is used for cung while the NC machine axis rotates. Wrap milling is designed to be used with a barrel stock rotang about an axis. For a standard milling machine, the rotaon axis can be parallel to the x-axis (A-axis), y-axis (B-axis) or z-axis (C-axis). For a mill/turn machine, the rotaon axis is typically the C-axis.

Cut Along a Contour ....................86  Rough and Finish the Pocket..91  Copy and Rotate Operatio ns ...94 

Wrap milling should not be confused with index milling. Indexing, or 4/5-axis milling, refers to the situaon where the NC machine axis (or axes) rotates to a new orientaon, then cuts aer the NC machine stops rotang. This project will show you how to set up rotary axes in ESPRIT and create rotary milling operaons to contour and pocket the OD of a part. Wrap milling operaons can also be performed on the ID and the face of a part.

The files for this project are available for download from ESPRITWeb » File Library » ESPRIT 2009 and from the ESPRIT CD. All dimensions in this tutorial are in millimeters. Make sure System Unit on the Tools menu is set to Metric. Before you start this lesson, you can review and simulate the cung operaons in the following file:

Milling - Rotary\rotary_milling_complete Rotary\rotary_milling_complete.esp. .esp. Project 3: Mill on a Rotary Axis

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Cut Along a Contour  You will begin this project by creang a contouring pass on the OD of the part.

Wrap Contouring The Wrap Contouring command lets you easily cut solids and 3-dimensional geometry while the stock rotates on the NC machine. You can create as many contouring passes as needed — a single finishing pass along the outline of the feature or mulple roughing passes offset incrementally from the feature. You can also define separate stock allowance values for the walls and floors. Entry and exit moves can be created while the stock is rotang or the tool can approach and exit the part without rotary moon. Wrap Contouring is used for milling on the OD or the ID of a part. To cut on the face, Rotary Face Contouring is used.

Machine Setup for Rotary Milling To enable rotary milling, you need to define at least one rotary axis and set the angle limits for the NC machine. Wrap milling operaons can be defined on any rotary axis or combinaon of two rotary axes. If available, the secondary axis will be used as the rotary axis. Otherwise, the primary axis is used. Creang a new rotary axis in ESPRIT is quite simple using the Machine Setup command on the Common Machining menu. Machine Setup lets you configure any type of 2-axis through 5-axis milling machine. You can define separate linear moon in X, Y, and Z for your machine components as well as rotary movement in A, B, and C. This allows you to customize the configuraon of the machine in ESPRIT to match your milling machine exactly and provide an accurate display of all machine moon, including rotary and index milling, during simulaon.

Open the Part File 1. On the File menu, click Open. 2. Locate and open the following file: Milling - Rotary\rotary_milling.esp This file contains all the features, cung tools and machine parameters needed for this project. 3. On the Smart toolbar, click Common Machining to display the toolbar. too lbar.

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Define Rotary Axes in Machine Setup The NC machine for this project uses standard X, Y, and Z linear moon on the machine head. The table has a rotary C-axis mounted on the A-axis.

Let’s take a look at the machine parameters in ESPRIT. 1. On the Common Machining toolbar, click Machine Setup. 2. Click the Assembly tab.

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3. Open the assembly tree for Head and then open the tree for Axes. (Click the plus sign to open a tree)

If you click on the X, Y, or Z axis you will see that they all have linear moon and that each has its own axis vector that defines the direcon of the axis. 4. Open the assembly tree for Table and then open Axes.

The order of the axes listed in Machine Setup is important. The first axis in the list is the primary axis. The second axis is the secondary axis and so on. In this case, the C-axis is mounted on the A-axis. Movement will first occur on the A-axis, followed by movement on the C-axis. Noce that the maximum rotaon allowed for the A-axis is 90 degrees.

The maximum rotaon allowed for the C-axis is a full 360 degrees. 5. Click OK to close the Machine Setup dialog.

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Create a Wrap Contouring Operation This operaon will cut the contoured shoulder on the OD of the part with a single pass using a 25mm end mill. The diameter of the stock is 25mm. The entry and exit moves are performed while the part is staonary. The lead-in and lead-out distances are both set to 20mm. The Move Type seng on the Wrap Contouring technology page controls the posion of the tool during the cung moves. In this case, the tool axis is posioned on the radial axis. Since the wall you are cung is parallel to the radial axis, you do not need to use the Preserve Radial Wall opon to prevent any possible gouging.

Step 1 Select the chain feature around the contoured shoulder

Step 2 Click SolidMill Tradional SolidMill Producon

Step 3 Click Wrap Contouring

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Step 4 Right-click inside the technology page and click Open

Step 5 Open the file: Milling - Rotary\Technology\1-WrapContouring.prc

Step 6 Click OK to create the operaon

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Rough and Fin Finish ish the Pocket  Pocket  This part has four pockets on the OD. To save me, you will create operaons to rough and finish one of the pockets then simply copy those operaons to the other three pockets.

Wrap Pocketing Wrap Pockeng lets you easily cut solids and 3-dimensional geometry while the stock rotates on the NC machine. Roughing passes, wall finish passes and floor finish passes can be combined in a single operaon and each type of cung pass allows the selecon of a different tool. Tool path can be produced on the OD or the ID of cylindrical stock and all tool paths are drawn in 3D for beer visualizaon. With the excepon of specific rotary opons, the sengs for Wrap Pockeng are idencal to the SolidMill Pockeng technology pages. Wrap Pockeng is used for milling on the OD or the ID of a part. To cut on the face, Rotary Face Pockeng is used.

Rough the Pocket You will first create an operaon to rough the pocket using concentric cung passes that start in the middle of the pocket and move outward. A rough stock of 0.20 mm will remain on the walls only. A second Wrap Pockeng operaon will be used to finish the walls. The roughing tool is defined in the General technology page and the cung strategy is defined on the Rough page.

Step 1 Select the chain feature around the pocket

Step 2 Click Wrap Pockeng

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Step 3 Open the file: 2-WrapPockeng_Rough.prc

Step 4 Click OK

Finish the Pocket Walls Next, you will create an operaon that only outputs a single wall finish pass using a 10mm finishing tool. The tool and cung strategy are defined on the Wall Finish technology page.

Step 1 With the chain feature sll selected, click Wrap Pockeng

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Step 2 Open the file: 3-WrapPockeng_Finish.prc

Step 3 Click OK

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Copy and Rotat Rotatee Operations  You now have rough and finish operaons for one pocket. You will quickly copy those operaons to the other three pockets. In this case, the default UVW axis will be used as the rotaon axis.

Step 1 Hold down the Ctrl key and select the two Wrap Pockeng operaons

Step 2 On the Edit menu, click Copy

Step 3 Set Transformaon Type to Rotate and click Copy

Step 4 Set Number of Copies to 3 and press the Tab key

Step 5 Check Use Origin for Rotaon Axis

Step 6 Click OK

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Simulate

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