GSM Setting It Correctly on a Tech Pack
GSM should be written into the tech pack with a value, a tolerance and a method. This removes ambiguity from quotations.
Definition to agree
grams per square metre, the standard measure of fabric weight. Working figures for GSM normally sit around 140-320 GSM for activewear in mainstream production. Note ISO 3801 fabric mass on the tech pack so nobody tests against an older revision.
Target value
Open the specification at 140-320 GSM for activewear, adjusted to the end use. Record elastane content alongside GSM, because blends shift the measured value. A result outside 140-320 GSM for activewear usually points to process drift rather than to the fibre itself.
Method line
Always pair the target with ISO 3801 fabric mass so the mill and the laboratory test the same way. Keeping reference values for GSM lets suppliers quote without extra sampling rounds. Ask for conditioning details together with ISO 3801 fabric mass, since both affect the reading.
Tolerance line
State plus or minus limits to keep production realistic while protecting the requirement. Working figures for GSM normally sit around 140-320 GSM for activewear in mainstream production. Note ISO 3801 fabric mass on the tech pack so nobody tests against an older revision.
Approval step
Approve the result on pre-production bulk rather than on development fabric only. Record elastane content alongside GSM, because blends shift the measured value. A result outside 140-320 GSM for activewear usually points to process drift rather than to the fibre itself.
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