The yarn count expresses the thickness of the yarn, and must be known before calculating the quantity of yarns for a known length of fabric. The yarn count number indicates the length of yarn in relation to the weight.
Three systems of yarn count are currently in use: the fixed weight; the fixed length and the Tex systems.
The fixed weight can be used with British and American weights and systems. The fixed length system and the Tex system are based on metric weights and measures. Tex is an internationally agreed system of yarn numbering that applies to all types of yarns, regardless of the method of production.
1: The fixed weight system
The fixed weight yarn count system is used for numbering spun yarns. It is based on the length of the yarn per lb. weight. The greater the length of the yarn weighing 1 lb., the finer it is, and the higher the count number. The count number gives the number of unit lengths, I.E.: skeins, hanks, etc, in 1 lb.;. E.g.: 10 hanks of cotton is abbreviated to 10’s cotton. 12 skeins Yorkshire woolen spun is abbreviated to 12’s Y.sk.
The unit length of 1’s count (i.e.: 1 unit count of 1 lb weight) varies with different fibres and spinning systems.
Wool: | ||
Woolen spun: | ||
Galashiels: | cut (unit length) | 200 yards (ie: 1’s wool has 200 yards per pound, 10’s has 2000 yards per lb., etc |
Yorkshire: | skein | 256 yards |
West of England: | hank | 320 yards |
American (Philadelphia): | cut | 300 yards |
Worsted Spun:
English and American |
hank | 560 yards |
Linen: | lea | 300 yards (ie: 1 lea linen has 300 yards, a 5 lea linen has 1500 yards) |
Cotton: | hank | 840 yards |
Spun Silk: | hank | 840 yards |
Plied Yarns:
When a yarn is plied, that is, when two yarns of identical count are twisted together, the yarn is twice as thick, and therefore the length of yarn per lb is halved. The numbering of the yarn states both the count of the single component and the number of components that make up the ply.
E.g.: 2/10’s cotton; the length of this yarn would be 10 x 840 divided by 2 = 4200 yards per lb.
It can be seen from the table below that a 2/20 yarn varies greatly in length depending on whether it was measured as cotton, linen, wool, or worsted.
2/20’s cotton | 8400 yds per lb |
2/20’s linen | 3000 yds per lb |
2/20’s wool | 2560 yds per lb |
2/20’s worsted | 5600 yds per lb |
2. The fixed length system
This system in used to number continuous filament yarns, ie: reeled silk and man-made extruded yarns such as rayon. It is based on a fixed yarn length to a variable weight and is measured in deniers. The denier count of a yarn
states the weight in grams per 9000 meters. The coarser the yarn, the higher the denier count number becomes. Thus: 9000 meters of 30 denier yarn weighs 30 grams.
3. The Tex system.
The Tex system is also based on the fixed length system. Ie: Weight per unit length. The Tex count represents the weight in grams per 1 kilometer (1000 meters) of yarn. For example, a yarn numbered 10 Tex weighs 10 grams per
kilometer. The Tex number increases with the size of the yarn.
The yarns are labeled according to an international code. The yarn count number is followed by the word “Tex”. The term “folded” is used in preference to “plied” yarn when two or more yarns are twisted together, and the direction of the twist is included in the formation.
E.g.: R 20 Tex/ 2 S – two threads of 10 Tex are folded in an “S” direction, therefore the resultant count (R) will be 20 Tex because the weight is exactly doubled.
Estimating the yarn count
When the yarn count is not known, it can be established by measuring a length of 10, 50, or 100 metres, depending on the count you judge the yarn to be. This is best done on a swift ( a skein winder) set to a circumference of 1 meter. The hank is then weighed in grams. Eg, if 50 meters of yarn weighs 2 grams, 1000 meters will weigh 40 grams and the count is therefore 40 Tex.
Copyright © Tracy Bradberry. Used with permission.
Thanks for the very informative article. May I ask what system is internationally recognised for hemp fibre?