Fibres, Yarns and Fabric Construction
Fibre to fabric
The chain runs fibre → yarn → fabric → finish. Fibres divide into natural (cotton, linen, silk, wool) and manufactured (regenerated such as viscose, and synthetic such as polyester, nylon, acrylic). Know the difference between staple fibres (short, twisted into yarn) and filament fibres (long, continuous). Staple yarns are hairier and weaker; filament yarns are smooth and strong.
Yarn structure
Yarns are described by twist direction (S or Z), twist level (low twist for softness, high twist for strength and crepe effects) and ply (single, twofold, cord). Blended yarns combine fibre properties, for example polyester/cotton gives strength plus absorbency.
Fabric construction
- Woven: plain (strong, firm), twill (diagonal, durable, drapes well), satin (floats give lustre but snag easily).
- Knitted: weft knit (jersey, stretches, curls at edges) and warp knit (more stable).
- Non-woven: bonded webs such as interfacing and felt, no grain line.
- Other: lace, net, felted.
Traps
Questions often ask which fabric is most suitable, not merely suitable - read the qualifier. Candidates confuse twill with a printed diagonal, or claim satin is always silk (satin is a weave, silk is a fibre). Selvedge, warp (lengthwise, stronger, less stretch) and weft (crosswise) questions catch many out.
Rule of thumb
If a garment must drape softly and stretch, choose a knit; if it must hold a crisp shape and bear strain, choose a firmly woven plain or twill. Worked example: a school skirt needing durability and shape retention - cotton twill, warp running vertically for minimum stretch.