Fundamentals of Dressmaking and Textile Knowledge
This domain tests whether you can link fibre, yarn and fabric structure to the way a garment behaves on the body, at the machine and at the iron. Expect questions on fibre identification, fabric grain, shrinkage, colour fastness and fabric selection for a given garment.
Fibre families
- Cotton and linen are cellulose fibres: absorbent, cool and washable, but they crease and may shrink unless pre-shrunk.
- Wool and silk are protein fibres: warm, elastic and lustrous. Wool felts in hot water; silk loses strength when wet, so both need mild soap and cool water.
- Polyester, nylon and acrylic are synthetic: strong, quick-drying, low-absorbency and thermoplastic, so a hot iron can glaze or melt them.
- Blends combine properties, for example polyester-cotton gives durability with some absorbency.
Fabric structure and grain
Woven fabric has lengthwise warp and crosswise weft; the selvedge runs along the warp. Lengthwise grain stretches least and is the direction of the grainline arrow. Crosswise grain stretches slightly more. Bias at 45 degrees stretches most and is used for cowls, bias binding and flares. Knitted fabric stretches in both directions and can ladder; non-woven interfacing has no grain.
Worked example
A question asks how to lay a flared skirt panel. The correct answer is on lengthwise grain at centre front, with the flare built into the pattern. Reasoning: grain controls stretch, so a panel cut on bias will stretch at the hem and hang unevenly. The grainline predicts the finished hang.
Traps
Confusing warp with weft; assuming the selvedge is the crosswise edge; ironing polyester at cotton temperature; ignoring shrinkage when calculating fabric quantity.
Key points
- Cellulose fibres absorb and crease; protein fibres need mild soap; synthetics are heat-sensitive.
- Selvedge marks the warp direction; lengthwise grain has least stretch.
- Bias stretches most and must not be used where stability is needed.
- Grainline placement predicts garment hang and fit.