A thread that extends under load does not necessarily return in the same way after the load is removed. Keep extension and recovery separate in the material discussion.
Coats distinguishes elongation from elasticity, the latter concerning recovery toward the original length after tension is removed. Coats — Thread Elongation.
Ask which behaviour matters
For a proposed sewn product, identify the relevant operation and intended use. A technical reviewer can help determine which information and evaluation are appropriate. Do not infer the complete seam behaviour from a single thread property.
Keep conditions with the result
Retain the exact thread reference and method behind a reported value. If the proposal changes material or construction, review the relationship again rather than carrying the old result forward automatically.
The useful outcome is a property discussion that supports the actual application. A general definition helps the team ask the right question, but it does not provide a universal acceptance value for every soft product.
Source reviewed 25 October 2026. Practical interpretation and original illustrations by PLUSHIP / Qunhe; examples are illustrative.
Related reading
Why Thread Consumption Changes With Construction
Lockstitch and Chainstitch Use Different Thread Formations