Textile Structure
how cloth is put together
Concept

Canopy depth — where it appears

How deep a closed canopy of protruding fibre reaches, being the decay length times the logarithm of the canopy criterion. The logarithm is why raising a cloth has a diminishing return: every doubling of the hair population adds the same fixed depth of nap and no more.

Named by 4 essays across 4 fields — each of them below, with the objects they name alongside it.

Hair, nap and pile are one construction at three settings. 12 mm of sheeting at one pair of scales, carrying each of this site's three protruding surfaces — 50 pixels to the millimetre along the cloth and 29 off it. They are the same object, fibre standing off a cloth with a density, a length and an anchor, and they differ by 9-fold in density and 4.8-fold in length. What actually separates them is the third line under each name: hairs are held by whatever the twist happened to leave, a nap by the float it was pulled from, and a pile by a W or a V through three picks. Only the last two were chosen. The pile's tufts are drawn in the float colour because that is what a woven pile is, and they are all one length because a blade cut them; the hairs and the nap are drawn as measured quantities and their lengths come from the population's own exponential. Each panel clips to the room it has, and the densest of the three is drawn at the model's own number rather than thinned.

Hair, nap and pile are one construction

This site now has three surfaces made of fibre standing off a cloth, arrived at from three different directions and in three different fields. They are the same object at three settings, and what separates them is not what they are but how much of them anybody decided.

fancy · Pile The force at an interlacing, which no longer lies in the fabric. A crossing of a relaxed jersey in section on the left, with the thickness expanded 3×, and on the right the contact force drawn at the angle the solve gives it — which is a true angle, unlike anything in the section beside it. The head of one course and the feet of the next lie one yarn diameter apart through the fabric, 0.167 mm, so the interlacing is not a point in a plane and the force at it is not in one either. It comes out at 38.30 mN a stitch, turned 11.75° out of the fabric: 37.50 mN along the wales, which is what friction has to hold, and 7.81 mN through the thickness, which is what holds the two faces apart. Divided by the area a stitch occupies the second is 15.1 kPa, or 113 mmHg — a pressure, and the quantity a compression measurement reports.

What a thickness gauge reads on a knit

The structure says two yarn diameters and the gauge says more, and the gap is not an error in either. A gauge lands on the highest crowns, through a canopy of protruding fibre, under a load that has already begun to compress both — and it does that on a surface that is nothing but crowns.

cloth · Contact Warmth is a canopy, and a canopy grows as a logarithm. Thermal resistance of sheeting against how much its hair population has been multiplied by raising, both faces counted. The unraised cloth is given no still air at all, because its hairs cannot reach one another — n_A λ² is under one and there is no canopy to hold air still. Past the threshold the canopy's depth is λ·ln(n_A λ²), so every doubling of the hair population adds the same depth of nap and no more: the steps here are 434 µm apiece, all the way up. At 256× the nap is 3.07 mm deep and worth 39 times the cloth it grows on, which is the whole reason a flannel is warm and a poplin of the same yarn is not — a canopy is two parts in ten thousand fibre, so its conductivity is air's, while the cloth itself is a quarter fibre. What is claimed is a conduction resistance across a depth of nearly still air; whether the air is still is a question about flow and is not asked here.

Warmth is mostly the hairs

This collection established that a fabric's thermal resistance is its thickness and not its fibre, and that twice the thickness is twice the warmth. It never asked what the thickness was made of. On a raised cloth almost none of it is cloth.

mechanics · Insulation The force at an interlacing, which no longer lies in the fabric. A crossing of a relaxed jersey in section on the left, with the thickness expanded 3×, and on the right the contact force drawn at the angle the solve gives it — which is a true angle, unlike anything in the section beside it. The head of one course and the feet of the next lie one yarn diameter apart through the fabric, 0.167 mm, so the interlacing is not a point in a plane and the force at it is not in one either. It comes out at 38.30 mN a stitch, turned 11.75° out of the fabric: 37.50 mN along the wales, which is what friction has to hold, and 7.81 mN through the thickness, which is what holds the two faces apart. Divided by the area a stitch occupies the second is 15.1 kPa, or 113 mmHg — a pressure, and the quantity a compression measurement reports.

How thick a knit is

Two centre lines pass at a diameter and each has a radius on either side, so a plain jersey is two yarn diameters thick with nothing fitted. It does not depend on the gauge, it lands inside the band of this collection's woven cloths, and it is lower than any gauge will read.

knits · Knit

Named alongside it

The objects these essays reach for when they reach for this one.

Canopy criterionCloth thicknessContact forceHair layerLoopNapRaisingAnchorageContact pressureCrownFibre volume fractionHairiness

All concepts