I saw on another website some modifications that I don't understand which were made to a big Macomber to facilitate rug weaving. Could someone explain the first and clarify the second?
1. The person moved the back beam out quite a ways away from the harnesses "in order to increase tension". While I can appreciate that it might potentially allow the back shafts to move up and down with less work while under great tension, I don't understand how it would increase tension. For that matter, when does one have enough tension? I weave a lot of rugs, and I have been known to give the brake crank one more "heave" and torn good, heavy linen rug warp. (That's really bad news, so don't do it.)
2. Per Peter Collingwood's book, they added weights to the beater -- 1 lb per inch of weaving width. I thought that a.) Collingwood likes vertical warp looms, and b.) the issue involved is not absolute weight but FOOT POUNDS of force. Although putting weight on the top of the beater increases the force at the end of the arc, doesn't one need to figure in the weight of the beater and the force applied and the trajectory of the beater. Since people who weave a lot tend to build up the appropriate muscles to deliver significant force on the beat, is this an issue? I constantly have to struggle not to overbeat balanced weaves.
Is their problem when they beat? I've found that if I beat on a closed shed and re-beat on the next shed, the beat stays in tight, but if you beat on the open shed the cloth tends to be looser.
I would also point out that I'm more of a little old lady than a muscle-bound athlete, so I figure if I can do these things, so can anyone else.
Please enlighten me.
The mod may have been on A Macomber but I think your question of rug tension could be best answered at the rug group site. A totality agree with you about over tensioning the warp.