Fibres, Yarns and Fabric Construction
What the exam tests
This domain examines whether you can trace a textile from fibre to yarn to fabric and predict how construction affects performance. Expect classification questions, weave and knit diagrams described in words, and fabric-choice justifications.
Fibre and yarn rules
- Natural fibres include cotton, flax, wool and silk; manufactured fibres include regenerated viscose and synthetic polyester and nylon.
- Staple fibres are short and must be twisted into yarn; filament fibres are continuous. Twist adds strength; low-twist yarns are softer and pill more.
- Blends combine properties deliberately: polyester/cotton gives strength and easy care with some absorbency.
Fabric construction
- Woven fabrics have lengthwise warp and crosswise weft, with a selvedge at each edge. Plain weave is firm and balanced; twill has diagonal ribs and hides soil; satin has long floats, giving lustre but poor snag resistance.
- Knitted fabrics are looped: courses run across, wales run down. They stretch, especially crosswise, and edge-curl.
- Nonwoven fabrics are bonded fibres, not yarns; they lack drape and seam strength.
Worked example
A learner needs a washable shopping bag that holds heavy groceries. A medium-weight plain-weave cotton canvas is suitable: cotton is strong when wet, plain weave is stable, and the firm sett resists distortion. It will shrink unless pre-shrunk, so wash and press the fabric before cutting. A polyester satin would be lustrous but snag easily and has poor seam grip; a single knit would stretch out of shape under load.
Traps that cost marks
Do not call satin a fibre or cotton a filament. Do not say knitted fabric is made from loops of weft only; identify courses and wales. Do not choose a fabric for appearance alone when the brief states washability, strength or drape.