I’m a new weaver and I’m having trouble with my edge threads breaking while I’m weaving. What’s wrong?
I hear your frustration! Once those selvedges (edges) start wobbling or popping the weaving gets frustrating. This is a common new-weaver problem—so rest assured you are not alone! Generally, the reason that your selvedge threads break is due to the sides pulling in (draw-in). The good news: this is a problem that can be fixed.
When there is excessive draw-in, each time the beater is pulled forward to beat, more stress is put on the threads at the edges. Also, when there is excessive draw-in, the selvedge threads may stretch and become slacker than the other threads. Because they are looser they become more subject to abrasion and breakage.
First, check to see what kind of draw-in you’re experiencing. To do this, bring the beater forward to the fell of the cloth and see how much the fabric is drawing in from where the selvedge thread is threaded in the reed. It is natural to have a little draw-in, say between ¼"–½", but more than this can cause problems.
To remedy draw-in, allow more weft yarn in the shed. Keep in mind that when your weft travels from one selvedge to the next, it does not go in a straight line, but must travel over and under the warp threads. To ensure that there is sufficient length for this to happen place your weft in the shed at about a 45 degree angle.
Another method is to bubble the weft in the shed. I find that this is slower than placing the weft in the shed at an angle, but I prefer this method for weft-faced placemats or rugs, though.
An end delivery shuttle can be helpful in managing selvedges when weaving on a table or floor loom. (I do not recommend end delivery shuttles for rigid heddle weaving.) A temple can be helpful especially for linen and rug weaving.
Finally, know that as you become more experienced (practice makes perfect), your selvedges will be straight and smooth—and warp breakage at the selvedge a thing of the past.