Jacquard Weaving and Designing

by T. F. Bell

Fig. 66

It frequently happens that figured stripes are required, running up plain or fancy textured goods, either forming borders to the outer edges, or merely ornamental stripes, say 3 or 4 inches from the edges of the cloth, as in towels, toilet-covers, &c. For this class of work it is generally most advisable to work the stripes with a small jacquard, and the plain or fancy texture of the body of the cloth with a shaft mounting. [Fig. 66] shows a mounting of this class; the shafts can be wrought by tappets in the usual way, and small cumber boards, as A, A¹, are fastened to the top rail of the loom for the harness to pass through. It is usual to keep the harness behind the heddles, and it is levelled in the usual way. The yarn may or may not be on the same beam for both portions, according to whether the take-up, or shrinkage, will be the same for both portions or not. Sometimes the shrinkage may be regulated to be alike in both by using different counts of yarn, or drawing it thicker into the reed; but perhaps in most cases two beams would be desirable, unless the texture is much alike for both the stripes and body of the cloth.

The lease rods for the yarn in the harness will not, probably, do to be the same as those for the body yarn, as the action of the heddles will be different from that of the harness. If the same rods will not suit, it is easy to have a pair for each warp, those for the harness being farthest back. Stripes of this description are frequently made in towels, glass-cloths, &c., for clubs or hotels, with the name of the company woven into them. A gathered tie is mostly used for these mountings, except when letters are required to be woven, in which case a gathered tie is not suitable. (See Letters and Monograms.)

TO VARY THE SET OF THE HARNESS

It may often be that in weaving figured piece-goods it would be an advantage to have a harness that would weave different degrees of fineness, so that the loom could be utilised for one when the other is not required. 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.

When changes of this kind are liable to take place, the cumber board should not be too low down, nor should the mails hang too close to the back of the slay; with the cumber board high and the harness a little back the strive will not tell so severely on the warp. When the cumber board is made of boxwood slips, they can be spread out a little in the frame, but when there is much of a slant in the harness this would take the mails off the level; though this can sometimes be counteracted a little by raising the cumber board slightly higher at one end than at the other.

The best plan when much of a change is required is to pass over the surplus rows of mails in the harness, as in harness work, as well as in shaft mountings, the mounting may be used for any coarser set of warp than it is built for—of course, if the width is suitable. This would necessitate the warp, or at least a part of it, being drawn out of the harness, and also requires a new set of cards for the new pattern, or for the same pattern on a new set of cloth. The surplus mails may be cast out in rows across the loom if many are to be rejected, or in rows across the harness (from back to front) if found more suitable, or when a small number of mails are to be left idle. Suppose for an 8-row harness, 400 machine, with 6 repeats = 2400 mails on 30 in., or 80 threads per inch, and it is required to weave a piece of cloth on this having 74 threads per inch. Drawing the yarn into a coarser reed, and, if only 30 in. wide is required, throwing off the surplus yarn at each side, would probably be the simplest method; but if the cloth to be woven is to have 60 threads per inch, every four throw of mails across the harness, or one-fourth of the harness, might be left idle, or the two back rows of the harness may be left empty. In the latter case the pattern could be painted on 6-row design paper as if for a 6-row machine, and in the former case the number of designs across the painting would be reduced by one-fourth, the card-cutter taking care that he omitted those rows on the card that have been thrown idle on the machine.

In order to reduce this trouble and expense to a minimum Messrs. Devoge & Co. have patented an expanding harness which is intended to admit of cloths of different degrees of fineness being woven without any trouble but a little setting of the cumber board and re-reeding the warp. The method of doing so is as follows:—There are two cumber-board frames, one above the other, as shown in the sketch [Fig. 67]; these frames are filled with slips which can be moved along when desired. The harness can be set for two degrees of fineness of warp, as is shown in the sketch. The slips in the upper frame, B, are set midway above the two positions for a slip in the lower frame indicated by the letters a and a¹. The black lines show the position of the cords when weaving the finer set. The only change required to be made is to shift the lower slip, a, to the position a¹, and to re-reed the warp; other changes can be made on the same principle, or by altering both sets of slips in relation to each other. When the slips are moved in the frames, they can be kept in position by interposing blank slips between them.