Inprocess Inspection - Sewing

Inspection procedures in Sewing Room

Introduction •

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In process inspection in the sewing involves the inspection of work from each operator, with a quality standard established to limit the amount of  bad work permitted and a provision for operators to re inspect and repair entire bundles should this limit be exceeded.  The dec decisio ision n on whe where re to plac place e the insp inspect ection ion stations will be influenced by various factors, such as the importance of operations, and controlling troublesome or key operations

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 The inspections inspections can ofte often n be performe performed d for two or more operations at the same time. In process inspection can be established at various inspection points in sewing operations, as opposed to the inspector literally selecting work at each operator’s work station. First, a complete manufacturing process chart should be made, clearly identifying the production or manufacturing steps for each type of garment made.

What to Inspect during Sewing?

Manufacturing process flow chart for men’s dress shirts 1. Marke Markerr lay made made acc accord ording ing to to cuttin cutting g ticke ticket. t. Marker lay checked 100% 2. Ma Marke rkerr and mater material ial del delive ivere red d to sprea spreadin ding g operation. Material spread. 3. Mac achi hin ne kni kniffe cut cut 4. Di Die e cu cutt ttin ing g sm smal alll par parts ts 5. Cu Cutt part parts s del deliv iver ered ed to pla plant nt

6. Collar Collar depa departme rtment: nt: Fuse stay stays, s, run run colla collarr tops, tops, trim points. Turn and press (shape), top stitch, trim tops. Hem bands, stich lining to bands. Band collar. Turn band ends. Top stitch bands. Trim and baste. Quarter-mark band. Button hole. Button sew. 7. Cuff dep departm artment: ent: Hem cuff cuff,, run cuff cuff.. Shape Shape cuff  top stitch. Button hole. Button Sew. 8. Un Unde derr fronts fronts:: Baste Baste neck. neck. Cre Crease ase Fron Front. t. Hem Hem button stay. Button Sew. Set Pocket. Set flap. 9. Upp Upper er Fro Fronts: nts: Bast Baste e neck neck.. Creas Crease e Fron Front. t. Centre Centre Pleat. Buttonhole. Set Pocket. Set Flap. 10.Sleeves: Piece binding. Bind Sleeve. Tack binding.

11.Backs: Pleat. Backs 12.Yokes: Label. Sew. 13.Attach yoke backs. 14.Assemble completed bundles of parts, any size, section, ply number, and /or shade. 15.Join shoulder seam 16.Join collar to shirt 17.Set sleeve, join side and underarm seams (Side fell) 18.Cuff attach, hem shirt, trim threads. 19.Button shirt, run collar, press, and fold. 20.Pack

What to inspect during sewing ? •

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 The insp inspecti ection on poin points ts or stati stations ons shoul should d be carefully selected so that the operations to be checked are neither covered by later operations, nor necessitate ripping good work to repair a defect. Inspection stations should provide a uniform work load for each inspector and should minimize the elapsed time between the completion of an operation and its inspection. Each operator should be told what standard of  work is acceptable and what is not. There should be a written quality specification for each job in the manufacturing process

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Wherever possible sketches of the garment parts should be included, illustrating how they are supposed to appear after completion. Dimensions and tolerances for critical points must be included. Knowledge of the factors that create problems in a particular operation helps to determine the specific dimension or characteristic to be maintained. Each inspector should be clearly told what to look for while inspecting various operations. Most inspections in the in process check points can be performed rapidly without sacrificing the accuracy, and quite large units of inspection should be expected of inspectors each day.

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 The insp inspecto ectors rs must be allo allowed wed with enou enough gh tim time e to inspect in greater detail when necessary and to carefully explain the quality problems to the supervisors. As with all the inspection activities, the thoroughness of inspection is more important than the quantity inspected.

Sewing Defects •

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Needle damage are evidenced by holes, picked threads, ruptured threads or other damage to the fabric; caused by wrong size or type of the needle, blunt needle, needle heat, or machine feeding difficulty. Feed damage, particularly on thicker sheer fabrics, or when machining over transverse seams, from incorrect type of teeth, excessive pressure by foot, improper alignment of feed and foot, damaged throat plate, excessive machine speed.

Sewing Defects •

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Skipped Stitches, from the hook irregularly failing to pick up the loop of thread from a needle’s eye owing to a number of causes. Thread breaks, arising from too thick a thread for needle, too thin a thread, needle heat, operator working un rhythmically, or too tight tensions. Broken stitches, arising from the wrong stitch type, too tight tensions, a badly formed joint in the seam where the second line of the stitch runs over the first and cracks it, sharp feeds, and too great a pressure.

Sewing Defects •

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Seam grin, arising from too loose a tension or too large a stitch, or use of the wrong stitch type. Seam pucker  , because of incorrect handling by the operator, misaligned notches, or tight tensions. Pleated seams, an extreme form of seam pucker, where operator failed to ease fullness evenly Wrong stitch density  . Too many give rise to  jamming  jamm ing and rapt rapture ure of fabr fabric ic thre threads; ads; too few to grinning or weak seams

Sewing Defects •

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Uneven stitch density  . Operator causes machine to snatch and does not allow machine to control fabric. Staggered stitch, from faulty feed motion, incorrect needle, and other machine parts. Improperly formed stitches, caused by bad tension, incorrectly adjusted timing, ill fitting machine components. Oil spots or stains.

Seaming Defects Seaming defects are usually caused by the errors arising from the interaction of the operator and the machine in the handling of the garment. Incorrect or uneven width of inlay  , arising from bad handling by operator, incorrectly set guide, incorrectly adjusted folder. In extreme cases, the seams burst open, raw edges show, slippage of  weave threads occur, or notches are exposed. Irregular or incorrect shape of the sewing line (sometimes called run-offs) in top stitching, arising from lack of or badly set guide, not following a mark, or incorrect handling. •

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Seaming Defects •

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Insecure back stitching, because subsequent rows do not cover the first row of stitching. Twisted seam leading to irregular puckering or the garment parts not hanging correctly when worn; caused by improper alignment of fabric parts, mismatched notches, and allowing one ply to creep against another. Mismatched check or stripes Mismatched seam, where transverse seams do not match (e.g., inside leg seams at the fork of the trousers)

Seaming Defects •

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Extraneous part caught in seam, an unrelated piece showing through the seam. Reversed garment part  , where part is sewn with the face side opposite from specification, perhaps when the part cut for one side of the garment is sewn in the other, or when the whole garment is assembled inside out. Blind stitching showing on the face side, or not securely caught on inside, arising from improperly adjusted bender. Wrong seam or stitch type used. Wrong shade of thread used.

Assembly Defects Assembly defects are perhaps caused by errors arising in marking and cutting, as well as sewing operations in the sewing room, or a combination of these. Finished components not correct to size or shape or not symmetrical  •

Finished garment not to size, arising from incorrect patterns, inaccurate marking or cutting, shrinking or stretching fabric, incorrect seam widths. •

Parts, components, closures, fixtures omitted  , caused by bad work flow, wrongly printed work tickets, parts omitted in cutting, careless operator. •

Assembly Defects •

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Components or features wrongly positioned  or misaligned arising from incorrect marking, or sewing not following the mark. (e.g., pockets, bar tacks, top stitching, button holes, buttons, hooks and bars, hooks and eyes, zips). Interlining incorrectly positioned, twisted, too full, too tight, cockling. Lining too full, too tight  , showing below the bottom of the garment, twisted, incorrectly pleated and so on.

Assembly Defects •

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Garment parts cockling, pleated, twisted, showing bubbles and fullness; for example, collar in relation to the under collar or the neck, sleeve in relation to the armhole, pockets, tapes, zips, pads in relation to the shoulder. Garment parts shaded owing to being mixed after cutting Parts in one- way fabrics in wrong direction, usually only small parts, such as pockets. Mismatched trimming

Glossary of Sewing room defects Sewing room defects Scissors or Knife Cut Tear

Self-explanatory Usually the result of excessive strain or snagging on the manufacturing machinery.

Needle Chew

Caused by use of wrong or blunt needle or machine feeding difficulty

Incorrect Shading

MaterialWhere components do not match exactly as to shade

Spots or Stains

Normally the result of a defective machine or a dirty work area.

Loose Threads

Can be caused either by malformed stitching or poor trimming techniques

Puckered Seams

An irregular seam surface usually caused by a) Inherent fabric characteristic, b) Needle puncture, c) Machine feed slippage or d) incorrect machine application

Pleated Seams

Caused by incorrect machine attachments. Machine sewing parts too large or small for fabric or seam desired irregularly cut patterns or fabric irregularities and operator feeding fabric faster than normal feeding action of the machine.

Wrong thread application, sewing machine malfunction, defective thread. Insecure Backstitching Original stitch row not covered with second seam. Wrong Shade of Thread Either caused by basic purchasing error, manufacturing defect by thread supplier or operator selecting wrong color from thread bin.

Thread Breaks

Irregular Stitching

Gauge

of Not using correct sewing machine or using single needle machine where machine is required

a

multiple

needle

Open Seams

Incorrect folder or poor operator technique. Sometime results from poor selection of type of  seam for fabric used or purpose of seam in garment.

Run Off 

Operator not following marking or not using mechanical aids such as edge guides to assure

error Wrong Seam or StitchManagement operating personnel Type

in selection-or failing to follow

specifications

 Tensions not adjusted adjusted correc correctly tly by opera operator tor Loose Thread Tension  Tensions  Tensions not adjusted adjusted correc correctly tly by opera operator tor Tight Thread Tension  Tensions Wrong Stitches perNormally caused by operators who lengthen stitch to increase machine speed Inch

Skipped Stitch

Caused by machine malfunction or excessive needle heat due to friction.

Broken Stitches

Often times the fault of wrong type of stitch for specific seam construction. Could be caused by excessive tightness in machine tensions

Closures Omitted

Normally an oversight by operators or failure by inspectors

Closures Misplaced.

Inattention or inexperience by operating personnel or improper alignment with gauges.

Finished Components NotCould be caused by faulty pattern, measuring to Tolerances cutting, previous operations in stitching or by indifferent operator attention to the specified tolerance Dimensions Tolerance

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of Could be caused by faulty pattern, cutting, previous operations in stitching or by indifferent operator attention to the specified tolerance

Poor operator technique and execution in not covering notch with seam. Omission of Any Part of Poor work flow, inattentive operator. wrong Garment work tickets or poor inspection Notches Exposed

Twisted Seam

Caused by improper alignment of fabric pieces. uneven tension or pull on plies being stitched

Pieces Not Aligned

Pieces sewn together not matched to each other

Reversed pieces

Where piece is sewn with face side opposite from specification; where part cut for one side of garment sewn in other.

Excessive Fullness

Caused where piece surface not smoothed prior to stitching.

Uneven Edge

Where stitching not straight formed in creasing machine

Ragged Edges

Usually occurs where knives on automatic button-hole machines do not dip smoothly.

Uncut Buttonhole United Stitch

Where knife failed to cut button-hole

or

improperly

Where tying stitches on automatic machines fail to secure.

Hole

Damage caused by faulty machine or related equipment

Faulty Gauging

Where operator has not sewn seam to specified Margin

Misaligned Closure

Closure components do not line up

Misplaced Component

Where part not positioned according to specifications

Misaligned Seam

Where seams .do not line up or cross specified point

Mislocated Reinforcement Uneven Stitch

Where bar tack or brad not in proper location

Needle Pick 

Failure of operator to replace a dull needle

Caught Place

Where a component of part of a garment been caught in an unrelated operation.

Caused by operator speeding up machine too rapidly or by holding back or pushing fabric through machine in variance with correct machine feed