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YARN
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YARN ,1 the name given to any textile fibre when prepared by the See also:process of See also:spinning for being See also:woven into See also:cloth. It is only in a few See also:minor and exceptional cases, such as the See also:weaving of haircloth or See also:wire, that there is any making of fabrics without the previous spinning of yarn. But yarn is of the most diverse description, and its value varies in proportion to its lustre, its See also:bleaching and See also:dyeing properties, its fineness, strength, See also:elasticity, uniformity of See also:diameter, smoothness, suppleness and See also:colour in its natural See also:condition. Yarn is single, folded and See also:fancy, and if See also:twisted to the right it is called twist way, and if to the See also:left, weft way, but those terms do not necessarily imply that the yarn is for either warp or weft. Single Yarn consists of fibrous See also:matter as twisted together during the process of spinning. If it is intended for warp it should be strong, elastic and smooth; if for weft it has less twist and is spongy. The raw material from which yarn is made has much to do with its See also:appearance and value. Thus See also:Cotton Yarn, although it varies from a soft spongy See also:thread to a closely compacted one, is generally dull in appearance, soft, pliable and of but moderate strength and elasticity. Dulness in this material is not, however, a See also:constant feature; when combed and gassed it is brighter than when simply carded, and when mercerized it assumes a high lustre. Cotton-See also:waste Yarn is of two classes, both of See also:low See also:counts, and is made from the cotton wasted in the preparing, spinning and weaving operations: one from soft material that had not previously been spun; the other from hard threads which are broken up into See also:separate filarnents. The best grades of cotton have been spun into commercial threads, 588,000 yds. of which weigh i lb, but for experimental purposes much finer threads have been spun. For yarn in more See also:general use the range is up to 250,000 yds. per lb. When spun from soft waste it is up to 13,400 yds. per lb, and from hard waste it is up to 2520 yds. per lb. See also:Linen Yarn is of two kinds, namely, See also:Line and See also:Tow. In their natural conditions both are stiff, inelastic and somewhat rough, but the method of spinning has much to do with their appearance. If spun wet they are more compact, smoother and brighter than when spun dry; yet line yarn is always stronger and better in these respects than tow, which is by comparison. soft, full and hairy. Both bleach to a pure See also: It is spun into threads that range up to 56,000 yds. per lb. See also:Silk is made into See also:Net, Spun and Noil yarns, all of which are readily dyed. Net Silk yields Organzine and Tram; both are, in See also:pro-portion to diameter, the strongest and most elastic of textile threads, and are highly lustrous and smooth; but organzine is hard twisted and used for warp, while tram is slightly twisted and used for weft. They give a range up to 450,000 yds. per lb. Spun Silk is made by combing and spinning the material wasted during the See also:conversion of cocoons into fabrics; it is less lustrous and elastic than net silk, 1 The See also:etymology is uncertain, hut apparently the word is cognate with " See also:cord." The meaning " See also:tale " comes from something spun out.also weaker. Silk Noil is made from the fibres rejected by the comber during the making of spun silk, and is inferior in all respects to spun silk. Mixed Yarn is obtained by mixing and spinning different fibrous materials together; as cotton and wool, silk and See also:ramie, and the proportions in which they are mixed vary from io% to 8o% of the most expensive fibre. The counts of single yarns made from different fibres are differently expressed, as are occasion-ally those spun in different districts from similar fibres. Cotton yarns are based upon the number of hanks, of 84o yds., contained in i lb; linen, upon the number of leas, of 300 yds., in i lb; worsted, upon the number of hanks, of 56o yds., in i lb. Wool is expressed in the See also:West of See also:England by the number of hanks, of 320 yds., in I lb.; in parts of See also:Yorkshire by the number of skeins, of 1520 yds., in 6 lb; in some parts of the See also:United States by the number of runs, of 16o0 yds., in 1 lb. Silk is expressed by the See also:weight of woo yds. in drams; also by the weight, in deniers, of 476 meters, the denier being an See also:Italian weight equal to b a s See also:part of i lb ; spun silk, by the number of hanks, of 840 yds., in i lb. Folded Yarn.—Yarn is folded to impart increased strength, elasticity and smoothness, and is used, both glazed and unglazed, for warp and weft in See also:ordinary fabrics. It is also made for such See also:special purposes as sewing, See also:lace-making, crocheting and See also:hosiery. The counts of these yarns are expressed according to the number of threads twisted together, as 2/500, 3/600; the former indicating that two threads of 5o0, and the latter three threads of 600, were twisted together to yield yarn of 25 hanks and 20 hanks per lb respectively; the See also:count of the single yarn being invariably named in the cotton, linen, woollen and worsted trades. With spun silk the practice adopted is to name the count of the folded yarn; thus, 70/2 and 40/3 imply that two threads of 1400 and three threads of 1200 were respectively folded together. Sewing Cotton should be smooth and strong, and much of it is from two to six cord. When two or three cord, the doubling twist is in the opposite direction to that of the singles. When more than three cord, it usually under-goes two twistings, the first in the same direction as the single threads, the second is in the opposite direction to, and more closely twisted than the first. Thus:—A six-cord thread is first folded and twisted two into one, then three strands of two See also:fold are twisted into one; after which it is sized and polished. Lace Yarn should be strong, elastic, smooth and spun twist way in the singles, but doubled weft way. Crochet Yarn is bulky, elastic and has a corded appearance. It is twice doubled: the first See also:time it is twisted in the opposite direction to the singles, the second time in the same direction as the singles. Hosiery Yarn is often a soft, bulky, single thread, but it is also folded, sometimes without being twisted, at other times it is slightly twisted. There are two types, namely, wool and silk, neither of which need be made,from the fibres named. For the former a hairy See also:surface is not objectionable, but the latter should be smooth, and may be gassed. Polished Yarn may be either single or folded, but it should be fully twisted and level. It is bleached or dyed in hanks, immersed in See also:size and polished with brushes while the size is moist. Fancy Yarn is made by twisting together threads of different counts, See also:colours, materials or twistings, at See also:regular or irregular tensions, and in the same or opposite directions. The effects thus produced are known in See also:commerce under a See also:great variety of names, of which the following are a few. Grandrelle is probably the one in greatest demand; it has a mottled effect which is due to uniformly twisting together two threads of different colours, but of approximately equal counts. In some cases the folding twist is slight, in others it is considerable. See also:Mock Grandrelle presents a similar appearance to true grandrelle, but is made at the spinning See also:machine by twisting together two rovings that are dyed in different colours. Flaked Yarn has a cloudy appearance imparted to it, (a) by twisting a hard spun thread with a roving, which, at regular or irregular intervals is made thick and thin by See also:drawing rollers; (b) by supplying, intermittently, during See also:carding or spinning, tufts of extra fibre to a thread; or (c) as in See also:Knickerbocker Yarn, by dropping small quantities of dyed fibres into two, similar or dissimilar, rovings at the spinning machine, or into two, similar or dissimilar, threads at the doubler. Corkscrewed Yarn has a See also:spiral surface effect which may be produced in different ways, such as twisting threads together that differ in tension, in count and in the quantity or direction of the twist in the single threads. If a fine, hard spun, single or folded thread be twisted with a coarse, soft spun single, the coarse thread will wrap itself about the fine one and give a corrugated surface. See also:Chain, and other effects may be given by two foldings and twistings, if for the first doubling a coarse soft thread is twisted with a finer one having See also:medium twist, and for the second a still finer thread is twisted with the twofold one, but in the opposite direction and with a different number of twists per See also:inch. See also:Gimp Yarn is spiral in structure and requires two doublings, the first to See also:form a twofold spiral, then, at the second doubling, a fine tight thread is added. Knopped Yarn is formed by twisting together several strands, one of which is at intervals delivered in greater lengths than the others, in See also:order to allow a See also:loop to be made; the direction of twist in one single may differ from that in another. Curled Yarn is produced by twisting two supple threads See also:round a longer and stiffer one, after which a See also:fourth thread is added. (T. W. 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