I am a new weaver, and I would like to know how to measure the length of fabric I have already woven. I have searched all of the weaving books I have on hand and no one seems to mention this. Once you have wound the fabric onto the beam, how do you know how much you have? One of my recipes says that one repeat will measure 5 inches. I think that would be only in a perfect world. Please help, and thank you!
You have to measure the fabric as you weave it and keep track of the measurements as you go. There are a great many different ways to do this, including pinning a tape measure to the cloth. I like to use little gold safety pins instead (no tape or anything pinned to the cloth). I usually pin them 20" apart along one selvedge, though the 20" distance depends on the length I’m aiming for (that’s about as much as I can measure before winding the cloth on the beam). Then I just count the safety pins to know how many sets of 20" I have.
To place the pin, I measure with the warp under tension, knowing that there will be some loss in length when the tension is released (the amount will depend on yarns and weave structure). I find measuring under tension more consistent than measuring with the tension released (and easier to measure accurately). When you release the tension, the warp starts relaxing. Depending on several factors, it will keep relaxing, so you might get a different measurement after two minutes than you would after five minutes. This variable (which I did experience as a negative when I was measuring coverlet panels that had to match) made me choose to always measure under tension.