Textile Materials, Tools and Equipment
This domain tests your working knowledge of the instruments used to measure and test fabric, the machines used to cut, sew and embellish it, and the CAD tools used to design it.
Measuring and testing instruments
- Tape measure and metre rule for length; GSM cutter (100 cm2) with a sensitive balance for mass.
- Pick glass for EPI and PPI; twist tester for turns per inch; crimp tester.
- Uster evenness tester for yarn irregularity; Martindale for abrasion and pilling; crockmeter for rubbing fastness.
- Colour assessment cabinet with D65 and TL84 lamps; spectrophotometer for numeric colour matching.
Design and CAD
Photoshop and Illustrator or CorelDRAW for repeat building and colourways; specialist packages such as NedGraphics and Reach for textile repeats and colour separation; Texcelle for jacquard. Colour separation converts a design into one layer per print screen.
Production equipment
Single-needle lockstitch, overlock (3 or 5 thread), flatlock, coverstitch, blind hemmer, buttonhole and bartack machines. Cutting: shears, rotary cutter, straight knife, band knife, die clicker. Pressing: steam iron, vacuum table, steam-air former.
Worked example
Specify the seams for a cotton-elastane knit T-shirt. Side and shoulder seams: 4-thread overlock, because the seam must stretch with the knit. Hem and neckline: twin-needle coverstitch, which stretches and covers the raw edge. Reasoning: on knits, choose the stitch by extensibility requirement, not by popularity. A lockstitch on a knit seam cracks when stretched.
Traps that cost marks
- Using a lockstitch on knit seams.
- Counting EPI with a plain ruler instead of a pick glass, giving a wrong count.
- Forgetting balance calibration before GSM weighing.
- Confusing pilling resistance with abrasion resistance.
- Naming CAD software without saying what it is used for in the workflow.