Selvage Under Special Control
The general appearance of the finished product being so dependent upon the character of the selvage, it is advisable to have these threads under special control, so that they may be treated in the best possible manner to produce a satisfactory shed, and allow the filling to get a good clearance. So as to secure a smooth well-rounded edge it is therefore necessary to have this on a special beam.
It will be seen, therefore, that in an ordinary piece of double cloth elastic web there will be required at least five warps: back, face, binder, edge and gut. Figures and fancy effects will often necessitate auxiliary warps. With very fine webs, having six threads to a cord, it is often found necessary further to split up the face to obtain proper working conditions. Figs. 1 and 1A show a six-cord web, together with warp calculations for the goods.
The employment of so many warps to each strip of web, which are automatically delivered by the friction let-off levers described in a previous article, prohibits the use of warps where the threads are equally distributed across the beam, as is the practice in wide fabrics, the method usually being to tape them on the beams.