Double chain stitch
Also known as: Two-thread chain stitch, Class 401
Two-thread chain stitch – strong, stretchy, standard for jeans inseams and waistbands.
Description
The double chain stitch (class 401) uses one needle thread from above and one looper thread from below that forms the characteristic chain loop. This seam combines high tensile strength (100–160 N/cm) with 25–35 % stretch and is therefore the standard join for jeans inseams, waistbands, saddle stitches in trouser crotches and seat seams in workwear.
Stitch density 3–4 per cm, mostly with cotton or poly-core yarn (Amann Belfil-S, Coats Astra). Sample products at Clubmartin: 5-pocket denims, chinos, cargo trousers. Sewn on Union Special 35800 or Juki MH-380. Unlike lockstitch, a broken chain can run further, making repairs tricky but keeping the seam very flexible.
Properties
| Stitch types | Class 401 two-thread chain |
|---|---|
| Needle threads | 1 needle + 1 looper thread |
| Usage | jeans, waistbands, workwear |
Related product categories
Sources & references
2- Wikipedia: Doppelkettenstich Wikipedia — Freie Enzyklopädie https://de.wikipedia.org/wiki/Doppelkettenstich
- Coats Industrial Threads coats.com https://www.coats.com/en/industrial
