In weaving it, I can make up for the issues by separately weighting the problem sections if I need to. I can also make the cloth take up the slack itself by weaving heavier cloth first. The higher deflection of warp threads traveling around the fat weft makes tension issues less problematic. I'll weave my lighter weight cloth on the second half of the beam.
In the meantime, I need to make sure that each section has the same length of yarn on it. Since the tension is loosening, it's becoming more difficult to fit it all within the pegs. It wants to spill over into the empty section next to it.
Teresa gave me a great idea on how to handle this. A little piece of aquarium tubing stuck on the dowels will make them longer and able to keep the threads under control. Thanks, Teresa!
For my next beam, I might use this technique across the whole width to give me an extra 20-30 yards without having to buy a bigger beam at this point. Of course I will buy one eventually so I can warp a second project while an assistant weaves the first one, but this shoestring startup can't afford any of that quite yet.