Sewing

Measure how much each fabric lot shrinks in washing and build that allowance into patterns and markers before cutting. Cotton Incorporated notes that brands expect shrinkage to be low and consistent.

Grade patterns from a documented table of body measurements. ISO 8559-1 defines how body measurements are taken; ISO 8559-3 sets out how to build such tables and the steps between sizes.

Plan markers so pieces fit together as closely as possible, and record pattern yield: the share of fabric that becomes cut pieces. A high-yield layout is called a ‘tight marker’.

Let knitted fabric relax before spreading, then lay each layer flat, tension-free, with one edge aligned. Automatic spreaders are built for this, to give more accurate pieces and fewer sewing rejects.

Group rolls by shade, number every layer, and keep each garment's panels from one layer through bundling and sewing. Numbering avoids matching colour by eye, which can fail under poor lighting.

Specify stitch type and density: overlock for knit seams, cover stitch for flat hems, and, per thread maker A&E, about 10–12 stitches per inch for jersey, 14–18 with elastane.

Use ball-point needles suited to the knit, sized ‘as thin as possible and as thick as necessary’ (Groz-Beckert). If a stretched test seam shows holes, go a size smaller. Replace worn needles.

Swap needles strictly one for one. After a break, match every fragment to a whole needle; if a piece is missing, isolate the garments. Keep records at least a year.

Cure to the ink data sheet, measuring the ink film, not the dryer setting: about 160 °C for most standard plastisols, about 121–148 °C for low-cure grades. Then stretch- and wash-test.

Balance the line: time each operation (its SMV) so no station becomes a bottleneck. In one knitwear factory study, line balance rose from 45% to 85% and productivity from 45% to 58%.

Use ISO 2859-1 sampling tables. At the usual inspection level (II), a lot of 3 200 pieces is judged on 125; at a buyer-agreed AQL of 2.5, 8 defective pieces reject it.

Control every needle. Primark's 2011 supplier policy: one needle out, one in; broken pieces taped to a record sheet; all childrenswear through a metal detector calibrated at least four times daily.

Make every product traceable. Since 13 December 2024, EU Regulation 2023/988 requires an identifier such as a batch number, plus the manufacturer's name, postal and electronic address, on the product or packaging.

Use a shareable social audit such as Sedex SMETA, done by Sedex-approved auditors against ILO conventions and local law. It is not a certificate; its value lies in fixing recorded issues.

Pack and ship dry. Marine insurers advise 45–70% relative humidity and 10–30 °C for garments, moisture absorbers in airtight packs, clean leak-proof containers, and no stowage with food or odorous cargo.