Page 145 - CTS - Sewing Technology - TP - Volume - 2-0

SEWING TECHNOLOGY - CITS

A thick place will appear as a small area of more closely spaced yarns or by a congregation of thick yarns. A thin
place is the opposite, as the fabric will appear to have loosely spaced yarns or a congregation of thin yarns.
Causes

Main causes of thick and thin places include (Fig15)

Fig 15

• Irregular let-off

• Incorrect setting of holding and releasing pawls on the ratchet wheel of take-up motion
• Gears of take-up motion not meshing properly
• Gear wheel teeth worn out or broken
Prevention: Ensuring proper training of factory personnel to set the let-off and/or take-up motion properly can
help prevent this fabric defect.
16 Bowing and Skewing
Bowing is a condition in woven textiles where filling yarns are displaced from a line perpendicular to the selvages
and lie in an arc across the width of the fabric. Bowing appears as rows of courses or yarn-dyed stripes forming
a bow shaped curvature along the fabric width. (Fig 16)

Fig 16

Skewing is a similar condition in which filling yarns are angularly displaced from a line perpendicular to the edge
or side of the fabric.
Bowing and skewing affects striped or patterned fabric quality more than for solid color fabrics, as the greater
contrast in patterns makes the distortion more prominent.
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.

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CITS : Apparel - Sewing Technology - Exercise 30