
Weaving Temples are used to decrease draw-in and to avoid broken selvedge threads. The ultimate goal is to obtain a woven fabric very close in width to the width set on the reed. There are commercially available ones made out of wood or metal. They come in different adjustable widths and can get pricy. I have a couple but of course not the exact size for my current project. As with many other things I use, this came from one of the weaving yahoo lists.
All you need is an alligator tarp clasp and a piece of cord to attach the clasp to the side of the loom. I use nylon cord. I advance the clasp as I advance the warp, every inch at the most.
This is an unexpensive tool that works wonders if you set the right width from the beginning. I do not undo the knots until I am done, just advance the clasp.
The result is even woven width with no broken selvedge threads. You could also screw an eye bolt to the side of the loom, I just don't like drilling holes in my tools so I go for the knot.
The clasps are available at the camping gear stores.