Friction Let-Off
Where there is limited loom space, and where a small number of threads are employed, as in the narrower garter fabrics, it is not as practical to have the warps made mechanically, and for this reason they are not likely to be put on the beams with as much uniformity of tension. In such cases it becomes necessary to have some automatic device that will correct any irregularities and maintain a uniform delivery throughout. The device for doing this is shown at Fig. 4.
The warp carrier A is fastened to the back rail, which carries the warp, over which is passed the friction cloth G which is hung from a rod D. The friction cloth is fastened at the bottom to the graduated warp lever E, which is bolted to the bottom rail H, as shown. The rubber threads constituting the warp pass in a direct line to the harness C, and then to the breast beam B. The lever E, and the weights F, allow for proper adjustment of the friction cloth so as to keep the lever level as the warp beam empties.
Fig. 3.—Rubber Warping Machine
In making the rubber warps for narrow fabrics such as garters and suspenders, where the last described method of warp delivery takes place, it is customary to work from an entire sheet of rubber, splitting it up into the required sections or strips of the various sizes called for in the warps. This splitting and warping process must be done in a long room where the warp can be stretched out to its full length, if possible, after it is unchained. These warps are usually about 60 yards long. The “head” of the sheet, or the part where the cutting knife has not gone through, is spread out flat on a series of hooks at the beaming machine and the tail end is fixed securely on a strong hook at the other end of the room.
The requisite number of threads for the several warps which are to be beamed are counted off and each different section is fastened to a beam. The end knot is laid snugly in the counter-sink made in the beam barrel for this purpose. A wide reed is used, covering the number of beams operated in the machine, which is usually about four, and the threads are reeded over spaces opposite the different beams. This reed can be moved sidewise across the face of the beams and each warp properly centered so as to keep the warp level. The operator then starts the beaming machine, which may be operated either by hand or power, and the warps are wound up. At the same time a helper walks towards the beamer carrying the tail end of the warps and keeping the tension as nearly uniform as possible. When the warps are all wound on the several beams, a lease is taken in each of them in the ordinary manner, and each separate section is securely fastened.
Fig. 4.—Automatic Friction Let-Off for Rubber Warps
Should floor space be limited, a horizontal reel is used, which is about six feet long and about five feet in diameter. On this the sheet of rubber is wound after being split in proper sections at the head end and divided by a coarse reed, so as to be able to distribute the different sections all across the reel. Each section can then be taken off the reel as required for the beams. The tension of the threads is governed by a weighted leather strap passed over the face of the reel.