Please excuse if this has been asked before, but what keeps the Y axis tracking straight? Is it just the tension on the belts or are there some side rollers or guides somewhere? I’ve got most of the published parts made and want to make sure I’m not missing something.
Start it straight and it should stay straight. In The instructions I say to set it by some sort of starting blocks and drive it down past the length of your cut. This is to make sure you are straight and it doesn’t need guides.
The wheels do all the work. But if you do need guides the z rails will make contact with the edge of the table if you want them to.