Overlock stitch (500 class per ISO 4915)
Also known as: Class 500 stitch, Overedge stitch
Standard definition of overlock/overedge stitches in ISO 4915 — covers stitch types 501 to 522 with 1 to 6 threads.
Description
The 500-class stitch (overedge stitch) per ISO 4915:1991 covers all stitch variants where the threads run over the fabric edge and secure it while at the same time forming a seam or protecting the edge against fraying. The class is numbered 501 to 522, indicating the exact thread count and threading path. The most important types are:
501 single-thread chain stitch on the edge (edge protection only, no seam) – often for sack closing. 503 two-thread overlock (economy operation, thin material, slightly stretchy). 504 classic three-thread overlock (standard edge finish for knits, sweat and jersey seams). 512/514 four-thread safety overlock (combines seam + edge, most common make-up seam on jersey). 515/516 five-thread overlock with double chain stitch + two-thread overlock (flat-felled alternative for denim and workwear). 522 six-thread safety overlock (heavy clothing).
- Standard: ISO 4915:1991 (stitch types and classification)
- Class 500 = overedge (over the edge)
- Most common make-up: 504 and 514
- Typically 1–6 threads
Properties
| Standard | ISO 4915:1991 |
|---|---|
| Class | 500 (overedge) |
| Stitch numbers | 501–522 |
| Most common make-up stitches | 504 (3 thread), 514 (4 thread) |
| Application | Edge finish + seam for knits/wovens |
| Threads | 1–6 |
Related product categories
Sources & references
1- Wikipedia: Overlock Wikipedia — Freie Enzyklopädie https://en.wikipedia.org/wiki/Overlock
