Seam Slippage How It Changes with Construction and Elastane Content
Seam Slippage does not stay constant when construction changes. Understanding the direction of change helps during development.
Effect of knit structure
Loop length and density move results first, usually before any yarn change is made. Working figures for Seam Slippage normally sit around below 6 mm at 60 N in mainstream production. Note ISO 13936-2 fixed load on the tech pack so nobody tests against an older revision.
Effect of elastane content
More elastane raises recovery but changes the value measured by ISO 13936-2 fixed load, so retest after any blending change. Record elastane content alongside Seam Slippage, because blends shift the measured value. A result outside below 6 mm at 60 N usually points to process drift rather than to the fibre itself.
Effect of finishing
Heat setting and softeners shift results, which explains differences between a hand sample and bulk. Keeping reference values for Seam Slippage lets suppliers quote without extra sampling rounds. Ask for conditioning details together with ISO 13936-2 fixed load, since both affect the reading.
Typical range
Working values stay around below 6 mm at 60 N for mainstream activewear. Working figures for Seam Slippage normally sit around below 6 mm at 60 N in mainstream production. Note ISO 13936-2 fixed load on the tech pack so nobody tests against an older revision.
Development advice
Change one variable at a time, then verify against ISO 13936-2 fixed load before moving to the next sample round. Record elastane content alongside Seam Slippage, because blends shift the measured value. A result outside below 6 mm at 60 N usually points to process drift rather than to the fibre itself.
