On this beam, I am using lots of mercerized cotton thread, which is less forgiving of tension irregularities. I'm also using yarns plied from many skinny threads. These plied yarns are less forgiving, too.
As a result, I'm having tension issues in the form of 3 slack sections. Here's how I fix them.
Section 28 is quite loose. Sections 27 & 29 are less loose. My solution is to separately weight those sections. 28 is on its own weight. 27 & 29 are sharing a larger weight.
Once I've collected enough slack from those three sections, I need to get that slack out of the way. To do that, I wait until I get to a cut mark between two batches of products. At the cut mark, I move all of the slack to the fell line and tie it up there. When I cut the two pieces apart, I'll also cut off the slack.
Now I have a choice moving forward: buy a real tension box before the next beam or use stretchier unmercerized 8/2 yarn until I can afford the new device. The cost ends up about the same, except that if I buy the new tool I'll have it from then on. Buying more expensive yarn has to be done for each beam. Before I can do either one, though, I need to sell some of the new white cloth. Back to the loom!