Page 138 - CTS - Sewing Technology - TP - Volume - 2-0

SEWING TECHNOLOGY - CITS

Module 5: Quality Control & Inspection

EXERCISE 30: Quality control - Fabric Defects

Objectives

At the end of this exercise you shall be able to
• know about fabric inspection and 4-point system
• check the fabric for fabric defect
• list the types of defect
• identify the cause of defect and how to prevent it.

Fabric Inspection

The “quality” of fabric from your supplier doesn’t meet your standards. In fact, it has a lot of problems. Fabric
inspection reveals countless defects ranging from drop stitches to color shading variation.
The 4-point system is the industry standard for evaluating fabric quality in the inspection industry. This system
assigns penalty points to a roll of fabric according to defect size, quality and significance.
But you must understand the different types of fabric defects to look for before you can use the 4-point system.
Fabric defects • Holes

• Horizontal lines • Defective selvage
• Shade variation • Snags
• Dirt/stains • Thick place/thin place
• Uneven dyeing • Bowing and skewing
• Drop stitches • Needle lines
• Misprinting • Coarse pick
• Crease marks
• Barre • Coarse end
• Neps/knots • Broken pick
• Abrasion marks • Broken end
• Splicing • Missing end/end out
• Filling bar
1 Horizontal Lines
This fabric defect is defined by irregular lines that run from side to side.(Fig 1)
Causes
Horizontal lines are generally caused by:

• Faults in the bobbin (the barrel used to hold yarn in place)
• Irregular thread tension
Prevention
Preventing the appearance of horizontal lines in fabric is quite straightforward. Regularly replace the bobbin and
frequently check thread tension and positioning.
2 Shade Variation
One of the more obvious visual defects that can be found on raw textiles, shade variation is defined by a difference
in depth of shade and color from roll to roll or piece to piece. Shade variation in fabric is caused by:(Fig 2)

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