Belt move too low and goes over flange

Hello, I have a problem with my upper belt in my 3.1: Despite having the pulley adjusted correctly (same height as the idler bearings) the upper belt keeps moving down and over the flange eventually blocking the whole systems. The upper bearings as well as the pulley all have the same height (distance according to ratrig instructions). Any ideas what could be causing this?
14 Replies
solid-orange
solid-orange•16mo ago
No description
solid-orange
solid-orange•16mo ago
No description
solid-orange
solid-orange•16mo ago
Instead of the pulley pushing the belt up it just wraps around it
SwissStar_BL_2
SwissStar_BL_2•16mo ago
Does it move up and down if you move the carriage? How tight are your belts?
solid-orange
solid-orange•16mo ago
solid-orange
solid-orange•16mo ago
Yes it does, see the video. But at this point I think the belt is too damaged to go on Regarding the tension: I loosened and tightend them and what's shown on the video happens regardless @ptegler : If I move the carriage by hand it moves up and down. Both videos show me moving the carriage by hand. The second one is moving the carriage from left to right
ptegler
ptegler•16mo ago
as you move that carriage... the upper belt across the back is lowering well before the belt drops on the motor pulley. That is telling me that rear corner idler is misaligned or shimmed incorrectly. It's walking down on that corner idler BEFORE it walks down on the motor So the pulley nearest the Y rail, is aligned ok with the motor as the belts walks back up where it should be
solid-orange
solid-orange•16mo ago
Thanks for the insight, but I measured the height of both (thanks to the FMMM quickly done) an both idlers are at the exact same height Which is what makes it so strange for me And the thing is: The belt actually goes below the idler that is in the corner a gets stuck between the frame and the idler
ptegler
ptegler•16mo ago
ahhhh.... ok...well the only thing that would shift that belt like that is the pulley pivot is not vertical! I'll bet there is some skew in your upper and lower metal mount plates in the tightened positions.
solid-orange
solid-orange•16mo ago
solid-orange
solid-orange•16mo ago
@ptegler : Thanks for your ideas: I replaced the belt and now it works again. my hypothesis: A while ago the pulley slipped down the shaft (about 2mm) and I noticed it too late. The lower part of the belt might have been damaged and lost its strength. But I hope this was it and nothing else
ptegler
ptegler•16mo ago
yep,,, big difference there. congrats
solid-orange
solid-orange•16mo ago
But I find it interesting that a worn out/damaged belt can cause something like that. Thanks a lot for your help 🙂
Animatrix
Animatrix•8mo ago
thanks for this observation, will try to replace my belts. In a similar situation. Everything lined up