Scrap Yarn Spreaders and Draw-In
Every time I begin weaving, my fabric draws in, a half inch or so, right at the beginning. After that, my selvedges are fine. I use a heavy yarn to spread my warp before I begin weaving. Could that be what is causing the draw in—the change from the heavy to the finer yarn? How can I fix this?
Many weavers use a heavy “scrap” yarn (or rags or nylon stockings or toilet paper) to “spread” the warp before weaving. The purpose of doing this is not really to “spread” the warp (as in make it wider) but to space the warp threads evenly, the way they need to be for weaving. Usually, this is especially important if the warp is tied onto the apron rod in big chunks (an inch or more of warp width). Gradually, with the picks of “scrap” yarn, the clumps become evenly aligned warp threads. If the scrap yarn is thick, the warp does spread out at the edges, more than it would with a fine yarn, say a yarn of the same weight as the warp yarn. What is happening in your case is probably normal, especially if you have no problems with further draw-in after that and your selvedge threads don’t fray or break.
However, I find the sight of that heavy yarn (or rags or nylon stockings or, yuck, especially toilet paper) really unappealing. Some inches of warp are also wasted in that process. Instead, I like to tie the warp onto the apron rod in small groups (a half inch of warp width or less), and then just start weaving, using the yarn that will be used in the project. The first half inch of weaving (or less) will do the job of aligning the warp threads, and I can unravel whatever weft threads of that part that aren’t usable when I take the fabric off the loom. This way, I love the piece I’m weaving from the getgo. Some weavers “spread the warp” by inserting only 3 picks of the intended weft yarn without beating them and then pulling all 3 to the fell with the beater. For many warps, inserted that way, the 3 picks alone will pull all of the warp threads into alignment (especially if the tie-on groups are small).