Whip plaiting: the taper by rule.
Strand width from the core, lace length, and dropping pairs on plan — the plaiter's numbers before the first cut.
Strand width: the 4.6× rule
Over a core of diameter D, the total strand width ≈ 4.6 × D — so each strand ≈ 4.6 × D ÷ strand count. Why that number: at the usual plait angle the strands sit about 43° to the axis (4.6 ≈ 2π × cos43°). The plaiters' boards carry it; the forum threads test where it breaks — it runs short on thin cores, so an alternative is 1.5 × circumference (4.71 × D). The app switches to counting lace thickness (+ thickness per pass) when you ask it.
Lace length
Cut lace at 1.6 to 1.8 × the plaited length (the app's default: 1.7×). Measure on the first whip: the taper's drops give back a little.
Dropping pairs
| rule | what it does |
|---|---|
| drop in pairs | keeps an even count for round plaits — the usual 12 → 10 → 8 progression |
| "follow the taper" | each pair drops when the ideal strand count passes halfway between the current count and the next — the width stays even either side of the taper |
| the overlays | nylon overlays usually carry 12 to 24 strands (the whipmaker's own figures) |
Paracord plaited flat: 550 ≈ 4 mm wide, 325 ≈ 3, 95 ≈ 2 — the estimates, and the field's editable: measure yours. The whole page = the app's WhipMath's own rules with their sources (the plaiting forums + the whipmakers).