Fig. 6A.—Harness Draft and Weave for Three-Quarter Inch Loom Web
Fig. 7A.—Harness Draft and Weave for One-Half Inch Lisle Web
Fig. 8A.—Harness Draft and Weave for Three-Quarter Inch French Web
Fig. 9A.—Harness Draft and Weave for Three-Quarter Inch Cable Web
In the harness draft shown, it will be seen that one harness is employed for the rubber and one for the gut. It is thus possible to shed the gut harness so as to open more than the rubber, having it travel both higher and lower than the rubber harness at each alternate pick of the loom. By this movement the gut threads will be kept in the desired position, and at the same relative side of the rubber threads in each of the several pockets designed to carry them both. If, from any unusual cause, any of the gut threads get away from their proper places it is easy by this arrangement of separation to lift the gut harness at any time, insert a thread of cotton between the gut and rubber threads, and put them in their proper places when commencing to weave again.
The weave employed in the making of webs of this kind, although of a very simple character, involves a condition which does not favor a straight well woven fabric unless great care is taken to offset troublesome tendencies. The nature of the weave is such that at one pick the binder harness changes, while on the next pick it remains open and does not change, the rubber and gut harness changing only. The result of this movement is such that one shed clears for the reception of the filling much better than the other, so that at one side of the web the filling will hug the edge wire, shown at W in Fig. 6A, while at the other side of the web the failure to get a good clearance prevents the filling getting so snugly around the wire. Therefore, as the web draws away from the edge wire in the process of weaving, the tendency is for one selvage rubber cavity to be small, while the other is large, which means that at the open side there is a freedom for contraction of the edge rubber which is not present at the other side, and a long-sided uneven web is the result.