B belt on A drive riding up on pulley

[Nephilaw]

I'm not quite sure why, but for some reason, the B belt on my A drive rides up on the pulley really badly. I've had my Voron working before, but not well, as tightening the belts accentuates the problem, and I didn't realize that that was what it was until a little while ago. I tried getting the chaotic labs ab tensioners and I've also tried their carbon fiber gantry parts but it hasn't fixed it. It's a form bot 300 kit. Any help on this would be super appreciated so I can finally get my Voron working right.
Attached is a video of the belt riding up.

 

[shiftingtech]

The vast majority of wandering belts are related to belt tension: over tightened belts tend to wander (though yours seem more dramatic than most)

How have you set your belt tension?

A racked gantry can also contribute.

another possible cause is misalignment of the b motor pulley. If it's too high or low, it can cause the belt to twist around.

Unfortunately, there's also a self-fulfilling prophesy aspect: once some actual problem (belt tension or whatever) causes a bunch of escapes, the edge of the belt gets worn down. Once that happens, even if you fix everything else, the belt will still misbehave. At that point, the only fix is replacement

 

[Nephilaw]

OK, I think I may have found the issue. I might have a bad print of my x carriage. I saw that the b belts were coming up on an angle to the belt clamp on the carriage instead of coming straight across. I'm reprinting them right now, I'll let you know if that was the problem. Thank's so much for your reply!

 

[NoGuru]

Gantry alignment can be difficult. I like to assemble it very loose and continually rack and tighten a little at a time. This means getting the belts tension very close, then tighten each idler maybe one turn each at a time, and counting the turns. Then I rack the X beam back and forth in all directions to help align.