Trouble with Edges
I am having trouble with my edges. One consistent problem I notice is that the fell is not straight. It slants downward at both sides. I have beamed the same warp several times, as I think this must be related to tension. Can you help me?
There are several possible reasons for a fell that is not straight, that either sags downward (toward the front beam) or slopes upward (toward the reed) at the edges.
If the fell slants downward at the edges, one of two causes is possible. The first is that you might not be turning the weft firmly enough at each selvedge. In this case, the warp actually becomes less dense there, allowing the weft to pack in more (where the warp is more open, the weft sett can become tighter and more dense). The second possibility is that the tension on the edge threads is tighter than on the rest of the warp. The first cause is the most likely. Make sure the density of the warp threads is the same at the selvedges by watching how firmly to pull the weft at the edge as it enters the shed.
If the fell slants upward at the edges, one of two causes is possible. The weft might be drawing the edge in, either because you are pulling the weft too firmly as it turns, or (more likely), you are not allowing enough weft slack in the shed to accommodate its take-up. For balanced weaves, you should leave about a 30 degree angle of weft in the shed before you beat. Another possible cause of an upward slant can be that warp tension is firmer on the edge threads.
A difference in warp tension on the selvedges can have several causes (other than not being tied on with even tension throughout). If the width of the warp on the beam is wider than the width in the reed, the warp may spread out on the edges only, making the density of threads going around the beam less on the edges than in the center of the warp. The warp threads would therefore be going through a shorter circumference on the edges, and as the beam unwinds, they would become more taut, since in reality they are taking a shorter path around the beam. You would know this happened if, after you beamed the warp, the remaining warp length was much greater on the edges than in the center.
If the warp becomes looser on the edges as you weave, chances are you are experiencing draw-in. The more crowded the edge threads (and the greater the resulting upward slant) the harder the warp threads at the edge will be hit by the beater. If the warp wasn’t beamed at very firm tension, the edge threads will tighten around the beam as they are beaten and become looser at the fell.
The solution to all of the possible causes is: Beam with very firm even tension at the width of the warp in the reed. Allow enough weft slack to accommodate the weft’s over and under path, and turn the weft just firmly enough to keep the warp sett the same at the edges as it is everywhere else.