Yarns and Fabrics
This domain covers how fibres become yarn, how yarn structure affects fabric, and how woven, knitted and non-woven fabrics are built and handled.
Core concepts
- Spinning twists staple fibres into yarn. More twist generally gives a stronger, harder yarn; too much twist can make it lively or kinky.
- Yarn count can be indirect or direct. In the cotton count (Ne), a higher number means a finer yarn: 40s is finer than 20s. Denier is direct: a higher denier means a heavier, thicker yarn.
- Woven fabric has lengthwise warp and widthwise weft; the selvedge is the finished edge. Knitted fabric is made by interlocking loops and usually stretches more. Non-woven fabric is bonded rather than woven or knitted.
- Grainline, warp direction and selvedge matter in cutting because fabric behaves differently along and across grain. Bias has the most stretch.
Worked example
A buyer wants a light shirting and a durable casual jacket. Compare 40s cotton with 20s cotton. The 40s yarn is finer, so it gives a lighter, smoother cloth suitable for shirting. The 20s yarn is coarser and stronger, so it gives a heavier cloth suited to durable casual wear. The reasoning uses the indirect count rule: higher Ne = finer yarn, not heavier yarn.
Traps that cost marks
Do not mix up direct and indirect count systems. Do not say knitted fabric has warp and weft. Do not cut a pattern piece across the grain when the pattern says otherwise. Remember that bias stretches even when the fabric is woven.
Exam focus
Count calculations, weave and knit diagrams described in words, and grainline questions.