Craft · 6 pages · 12 min

Why thread has a twist

Twist locks fibers together by friction so a thread holds a pull instead of drifting apart.

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From the opening

Thread has a twist because most fibers are short or slippery, and a spiral wind forces them to grip one another so the strand can take a pull. Without that helix the bundle is only a loose roving that drafts apart under a modest load. The opening covers twist builds friction between fibers, s and Z name the slant, and ply twist opposes the singles.

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Inside

Twist builds friction between fibers
S and Z name the slant
Ply twist opposes the singles
Too little twist pulls apart
Where the idea stops applying
A distinction worth keeping

Sources

Twist as fiber friction in yarn
Balanced ply in sewing thread

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Why thread has a twist

From the opening

Inside

Sources

Also on the desk