Textile Fibres, Yarns and Fabric Construction
Scope
Fibre classification, yarn numbering and fabric structure determine handle, shrinkage, seam performance and care.
Core rules
- Fibres: natural (cotton, wool, silk, flax) and man-made (viscose, polyester, nylon, elastane). Cotton absorbs and creases; polyester is strong and thermoplastic; viscose drapes but loses strength wet; wool felts.
- Yarn: staple versus filament. Ne = 840 yd per lb; tex = g per 1000 m; denier = g per 9000 m. Higher Ne is finer; higher tex or denier is coarser.
- Fabric: woven (plain, twill, satin), knit (weft, warp), nonwoven. Warp runs lengthwise, weft crosswise, bias at 45 degrees stretches most. GSM and thread count describe mass and density.
- Tests: shrinkage, colourfastness, GSM cutter, twist direction (S or Z).
Worked example
Convert 40 Ne cotton to tex. Reasoning: tex = 590.5 / Ne = 590.5 / 40 = 14.8 tex. A 2/40 Ne yarn is two 40 Ne yarns plied, so the resultant count is about 20 Ne and the tex about 29.5. This matters when substituting yarns for the same fabric weight.
Traps
Confusing denier and tex; assuming higher GSM is always stronger; ignoring bias stretch when cutting; mixing shrinkage rates of shell and lining.