Page 118 - CTS - Dress Making - TP - Volume - 1
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DRESS MAKING - CITS




           Causes
           Bowing and skewing can be caused by an uneven distribution of tension across the fabric width during dyeing or
           finishing processes. Improper stretching during scouring, dyeing or finishing might also cause bowing or skewing.
           Prevention: Correcting the tension settings on processing machines should rectify these defects. You can also
           ask your supplier to fix bowing and skewing found during fabric inspection by reprocessing the fabric through a
           compactor or straightening machine.
           17  Needle Lines

           Needle lines appear in weft knit fabrics, and appear as prominent vertical streaks or lines in the fabric.
           Causes
           Defective needles are a direct cause for needle lines. Needle latches, hooks or stems might be: (Fig 17)
           •  Mixed
           •  New
           •  Dirty or contaminated with lint
           •  Bent
           •  Worn
           Prevention: If needle lines occur individually, you’ll likely only need to trace the needle line to the associated
           defective needle and replace it to prevent further needle lines. If needle lines appear in a band, you’ll likely need
           to replace multiple defective needles.
           An improper dial or cylinder condition with the machine might also cause needle lines. Verify that your supplier
           has established and maintained proper maintenance and cleaning policies to prevent future issues with needles
           and equipment.
           18  Coarse Pick
           A coarse pick is where the filling yarn used in the fabric is unusually large in diameter. (Fig 18)

             Fig 17                                    Fig 18























           This defect is also known as coarse filling or thick filling.
           Coarse pick is usually classified as a major defect during fabric inspection.
           Causes and Prevention

           Probable causes for coarse pick include:
           •  Lashing of broken end with adjoining end at roving frame
           •  Disturbed weight of back-top rollers at roving frame and ring frame cause the material to slip under the backtop
              roller and crease a coarse yarn.






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                                        CITS : Apparel - Dress Making  - Exercise 34
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