Jacquard weaving

“ In designing for Jacquard weaving care must be taken that the ground weave will divide exactly into the number of ends in the harness, otherwise the pattern will be broken. Sometimes the figure will allow of the ground being broken at some point or other without the break being visible. Such opportunity occurs where the ground narrows down to a fine point; but in ordinary cases, where it is necessary to make a design with a ground weave repeating on a number not a measure of 400, some of the mails must be “cast-out.” ”

“ For a jacquard weaving plant the designing is the most important factor.
BOX LOOM WEAVES INCLUDING CREPES
Box looms are required for weaves such as bayadères, checks, plaids (see pages 63-65) , bengalines, crêpes, etc., where two or more shuttles are needed to bring out the effect.
For the crêpes (crêpe de chine, crêpe georgette) only two shuttles are needed, while plaids and other articles are made with more shuttles.
To weave such articles the loom or the lay must be fitted with two or more shuttle boxes on one or both sides of the loom. ”

“ The weft is struck up on the open shot, or before the heddles have closed the shed. Sometimes a sort of dobby is used below the lams, which enables the weaver to work the heddles with one treadle. In power looms a similar principle of front mounting is sometimes adopted, substituting a wyper tappet for the weaver’s foot; but a better plan, as it avoids having the cords passing through the yarn and heddles, is to have a box tappet, on the Woodcroft style, made with solid plates, and struck to give the rising and falling motion. ”

“ An ingenious method of working the heddles of a pressure harness by the jacquard was invented in Bethnal Green shortly after the introduction of the original machine. It was used for weaving the richest silk damask, which had 400 threads of warp per inch and about one-fifth that number of weft shots, so that five threads of warp might be drawn into each mail without making the pattern appear any coarser in the warp than in the weft. A sketch of this mounting is given in Fig 115. A shows the hooks for working the heddles, and B those for working the harness. ”

“ As has already been said, the nature of the shedding of a single-acting jacquard is objectionable for speed in working, for ease on the yarn, and for heavy work, or for well-covered work. The jacquard harness is levelled so that the yarn is all sunk, and the shed is entirely a rising one; it can easily be understood that when the griffe rises to open one shed, it must again fall before it can begin to rise to form the next shed. ”

“ Figuring with two warps and one weft is a common method of working, and gives three colours on the face of the cloth. An extra warp of fine yarn may be used for binding the wefts, admitting of the coloured weft being more used for figuring. Extra warps cannot be used to so great an extent as extra wefts, as they crowd up the reed and prevent proper shedding, particularly when soft or hairy yarns are used; but when properly suited to the reed they make a firmer and more regular cloth than a weft cloth, and on account of less picking the weaver gets over the work much faster. ”

“ Fig. 185 is the plan of drawing-in and weaving a carpet similar to that shown in section in Fig. 184. The draft is given at A, and the [278] treading and cording for a hand loom at B. A 10-row jacquard should be used for a 5-frame carpet, as twice over the 5 threads makes one row of the cumber board. Five threads are drawn into the harness, one from each frame, then two ground warp threads are brought through and drawn on two leaves of heddles. In weaving, one ground thread is raised and a shot thrown in; then all the pile warp and the same ground thread are raised for the next shot ”

“ Fig. 169
As the weaver sits at the back of his frame or loom when working, he has to come round occasionally to examine the face of his work. Sometimes he keeps a looking-glass in front to show him how he is getting on. He has also a rough pattern on the back of the cloth similar to that on the front, as the nature of the weave must give him the same on both sides were it not for the loose ends at each change [259] of bobbin, which have to be tacked up at the back. Tapestry weaving is a very tedious process of working, but in skilful hands very beautiful, and artistic results can be produced. ”

“ For weaving small quantities, for samples or special orders, this is often an advantage.
The usual method of procedure is to draw the warp into a finer or coarser reed if only a slight difference is required, and to pay no attention to the strive in the warp between the harness and reed. The better the quality of the warp, the greater the strive may be, but from 1 in. to 2 in. at each side is as far as it can safely be run when the harness is wider than the yarn in the reed; and if the reed is coarser than the harness, 1 in. at each side will probably be the maximum limit. ”

“ In weaving these fabrics healds are used to govern the ground warp, but a Jacquard is needed for the pile. It must form two sheds, the lower one to receive a shuttle, the upper one to make a selection of threads beneath which the wire is to pass.
Terry Looms.—Looms for weaving piled textures, of the Turkish towel type, have the reed placed under the control of parts that prevent it from advancing its full distance for two picks out of every series that separate one line of loops from another. At such times the weft is not beaten home, but a broad crack is formed. ”

“ Too large a shed should not be made with the doups, on account of the strain on the yarn: a small clear shed gives much more satisfactory work. The front cumber board, containing the doup leashes, may be shifted a little forward or back if thought desirable, so as to get the cross shed to spring as easily as possible, the amount of elasticity in the warp varying this considerably. The slip heald is raised for every shot by cording it to the brander or griffe of the jacquard, which for gauze work is generally a single-acting one. ”

“ The slackening bar must not rise so high as to raise the yarn that is above it, nor must it sink so low as to press the whip down on the back harness board, and it must be so regulated that within these limits it will give the proper amount of slackening, and prevent the whip warp from getting tight and drawing up the small back harness.
Fig. 138
Worsted makes the best weaving doups for strong work, but for lighter work cotton is mostly used, being finer and cheaper. Sometimes [212] polished linen yarn is used and makes a very smooth doup, but does not give the wear. ”

“ Weavers, like many other classes in Southern India, are eminently conservative. Even so trifling an innovation as the introduction of a new arrangement for maintaining tension in the warp during the process of weaving gave rise a short time ago to a temporary strike among the hand-loom weavers at the Madras School of Arts.
For the following note on the weaving industry, I am indebted to Mr. A. Chatterton. “The hand-weavers may be divided into two great classes— (1) plain weavers, who weave cloths or fabrics with a single shuttle, which carries the weft from selvage to selvage ”

“ I will talk about the weavers this morning. And the first thing I have to say is that this is no uncommon trade among birds. Take the nest of any of the common small birds that use hair for a lining, and you will be apt to find some part of it woven."
"But, Uncle Philip, you do not mean that [Pg 203] birds weave as smoothly and regularly as people do!"
"Not quite, boys; but still it is very fair weaving, and done as our weaving is, by working a hair or thread in and out between other hairs and threads, or roots, or bits of stick and grass. ”

“ In our efforts to place the hand-weaving industry on a better footing, we are endeavouring to improve the primitive methods of indigenous weavers both in regard to warping and weaving. In respect to weaving we have met with considerable success, as we have demonstrated that the output of the fly-shuttle loom is fully double that of the native hand loom, and it is in consequence slowly making its way in the weaving centres of Southern India. ”

“ The frame for the weaver is a simple wooden one, which stands upright in a corner of the house, where the women work at it when they have the cotton spun, by twisting it suspended from the hand to a ball, the thread being wound on a slight stick; both spinning and weaving appear to us very slow work, but time is never considered by the Indian ”

“ THE three principal movements in weaving are shedding, picking, and beating up the weft. By shedding is meant opening the warp threads to allow the shuttle containing the weft to pass over certain ends and under others. In the common [Pg 49] hand loom the shed is made by the weaver operating treadles with his feet. Fig. 35 shows the method of connecting the shafts or staves with the treadles for weaving a plain cloth. ”

“ In captivity one of the weaverbirds, the red-billed weaver, was studied at its nest building and it was found that the strong, intricate, and beautiful weaving of this species actually included knots of several sorts.
TAILORING The tailoring is done by birds of quite another group. They are Old World warblers of several sorts, some in southern Asia and some in Africa. The tailoring consists of sewing the edges of leaves together to form a place for their tiny nests. ”

“ When the weaving is nearly done and it becomes necessary to remove the healds, the rod is drawn out of the loops, a slight pull is made at the thread, the loops fall in an instant, and the straightened string is drawn out of the shed. Illustrations of the healds may be seen in Plates XXXV and XXXVIII and Figs. 42, 44, and 46, that in Fig. 46 being the most distinct.
§ VI. In making a blanket the operator sits on the ground with her legs folded under her. The warp hangs vertically before her, and (excepting in a case to be mentioned) she weaves from below upwards. ”

“ The weaver on the left holds a spool in her hand, evidently a piece of stick with the weft thread wound round it, which she is pushing through with her fingers. The weaver on the right holds a beater-in as shown in the Beni Hasan drawing. The breast beam is held in position by two pegs near the right one of which there is a curved article of indeterminate use.
Fig. 12.—Study of a Bedawin Arab weaving, from a sketch taken in the Forties of last Century, by Frank Goodall, R.A. The original sketch is in Bankfield Museum. The weaver appears to be provided with one heddle and a beater-in. ”

“ We know how closely analogous to ‘darning’ was the early weaving; and in our days it is not unusual to find stockings not darned at right angles, and it may be the women weavers of old sometimes put in the weft more or less out of true right angle. In the childhood of weaving we should expect different methods, and it may be, seeing that we have no selvedged cloth until very long after this time, that they experimented with a diagonal weft to see if it would not reduce the tendency to fray out at the sides.” The amount the warp and weft are out of the right angle is stated to be about 20°. ”

“ Besides the headles there is a hanging reed or comb, and between the reeds of it the warp threads are passed and fastened to a roller or cylinder. After throwing his shuttle once or twice backwards and forwards, the weaver pulls the comb towards himself, thereby pressing his weft and warp together, thus making the textile which he gradually winds from time to time on to the roller. This advance in the construction of the loom is also virtually of undateable age; and except for more substantial construction, there is little difference in main principles between it and the medieval loom of fig. ”

“ Stories of the weaving birds, particularly the African weaver, are interesting. It is said that two birds work together, one on the inside of the nest and the other on the outside, passing the grass and twigs in and out, until the home is completed. The children will enjoy, too, stories of weaving in other lands, material for which can be easily obtained. ”

“ None of the Audubon societies have even touched on the matter.
WEAVING The sewing and the weaving is done entirely in the construction of nests. To take up the weavers first, we can point to the Baltimore oriole, which makes a sac-shaped, pendant nest, often hung from the trailing tips of - 89 - elm branches. The walls of this sac are formed of fibers pushed and pulled back and forth with the birds' bills in a seeming haphazard way so that a roughly woven or stitched fabric results. But the finest weavers belong to that group of birds known as weaverbirds. ”

“ The several processes of twisting and untwisting threads, preparing skeins, etc., make combined labour a necessity in the weaving industry; and, wherever one finds a weaver settlement, he must find there a large number of these people, as is explained by the proverb that “the Chetti (merchant) lost by partnership, while the weaver came to grief by isolation.” When plying shuttles in the weaving process, the weavers always use their feet in shifting the warp, by treading on a press. Thus, if a weaver unfortunately happens to have a sore on his foot, it means loss to him ”

“ The transverse thread is beaten firmly home by means of a heavy prismatic piece of wood. The material used in weaving is yak or sheep's wool, either in its natural colour or dyed in the primary colours of red and blue and yellow, and one secondary only, green. Blue and red are used in the greater and equal proportion; then green. Yellow is very parsimoniously used. The thread is well twisted and is subjected to no preparation before spinning, leaving thus a certain greasiness in the closely-woven material that renders it waterproof. In weaving colour fabrics several shuttles are used. ”