Flatlock seam
Also known as: Flatlock, Flat seam, Flatlock stitch
Flat, stretchable joining seam without bulk – standard in sportswear and performance apparel.
Description
The flatlock seam is a flat-lying, highly elastic joining seam in which two fabric edges are butted together and overstitched with several needle and looper threads. Typical constructions use 3, 4 or 5 threads: two or three needle threads from above plus an upper and lower looper thread. Stitch density is 4–5 stitches per cm; strength reaches 60–90 N/cm at 30–50 % break elongation.
Because the seam sits flat against the skin, no chafing points occur – ideal for baselayers, compression wear, cycling jerseys and running shirts. Sample products at Clubmartin include the Merino baselayer long sleeve, trail-run shorts and yoga leggings. Sewing is done on flatlock machines (Union Special, Pegasus W600) with textured looper yarn, giving the seam a soft, breathable feel.
Properties
| Stitch types | 3-, 4-, 5-thread flatlock |
|---|---|
| Needle threads | 2–3 needle threads + 1–2 looper threads |
| Usage | sportswear, baselayer, compression wear |
Related product categories
Sources & references
2- Wikipedia: Flatlockstich Wikipedia — Freie Enzyklopädie https://de.wikipedia.org/wiki/Flatlockstich
- Union Special Flatlock-Maschinen unionspecial.com https://www.unionspecial.com/
