Belt is getting sucked into the abyss and causes huge layer shifts
Hey guys, normally I don't bother anyone else with my printer problems, but when an issue pops up for the second time, seemingly out of nowhere after a couple hundred hours of printing just fine I have to investigate.
My printer is a V-Core 3.1 with PC-CF printed parts, the white-ish stuff one the photos is jest some lubricant. As I said I already had this hardware issue a couple of months ago, back then I spent ages trying to figure out what the problem was, luckily now I knew what to look out for.
But back to the issue:
Towards the end of an 15 hour print job, I noticed a huge layer shift in X- and Y-Direction of over 2 cm. And that even though each layer before that had been laid perfectly (to my standards) on top of each other. As you can see on the attached photos, for some reason the top belt is getting dragged downwards from its regular path and by that is getting stuck somewhere in the back left belt assembly. Last time i had the same issue with the right back assembly, but I sadly I don't remember with which one of the belts.
My main question is whether or not somebody else had that problem and how they fixed it or even better what causes it? Is it some kind of design flaw of the printer itself or a construction flaw from my end?
On the second picture you can spot the damaged belt, which I have to replace because from now on it will simply get dragged down every single time it move into the assembly with its damaged part. And as you all now it's no fun to replace the belts since you have to disassemble a lot of stuff.
Anyways, already thanks for reading this long texts, I hope someone can shine some light into this abyss.
Portolasas
3 Replies
absent-sapphire•2y ago
i see the belt looks a bit wavy which is possibly worn out or over stressed. its possible this is causing the belt to "wander" off the idler thus pulling into the abyss of the extrusion. that is my first speculation from the pics.
harsh-harlequin•2y ago
thanks, I can ensure you the belts were just fine, they got that wavy as an result of being sucked in and compressed between the housing of the printed parts and the idler.
After doing some research I've noticed that some people had similar issues, it might have something to do with the fact that the idler pulleys are not perfectly aligned and thereby put uneven stress on the belts causing them to move ever so slightly as well as uneven wear.
But that's just speculations, I will install the dual metal plate mod for some better insight in the X and Y-Assemblies, hopefully that helps with some possible alignment issues.
Bear in mind that once the belt get uneven due to dmg or something they will tend to play around afterwards. Once damaged it’s better to replace them. (Unfortunately I speak from experience where I ruined two sets of belts in a week)
For the idler pulleys untighten the grub screws move the gantry manually and see how the belt moves.