UM3 belt is grinding on sides of gear

[Xalara 6]

I noticed my Ultimaker 3 making some squeaking noises and saw that one of the belts is grinding against the side. I've tried reseating the belt, but it just moves back into position grinding against the side. There is also rubber dust around the area. What can I do to fix this problem?

 

Video of the problem is here, notice how the belt tilts from side to side: https://drive.google.com/open?id=1TaaKxnoPsj6U6_DtYu8TmP99toA2VJoa

 

[geert_2 557]

I also had this on one belt on one of my UM2: a squeeking sound which turned out to be caused by the belt rubbing against a flange of a pulley.

 

I gently lubricated the edge of that belt with a little bit of silicone grease. But only the edge, and only a *tiny little bit*. Not on the teeth, otherwise it might skip teeth. And I used *silicone* grease: the thick white sort that is also used for microscopes and binoculars. This does not leak away and does not dry out.

 

Don't use petrochemical oils or greases on rubber: this may damage it.

 

This is not an official answer (I am not related to the Ultimaker company), but it solved the problem for me.

 

[Framar 38]

Hummm... I would check if the printer's axis are square. If they aren't then that would explain why the belt does not remain in the center of the pulley.

[Xalara 6]

Thank you, I'd like to avoid having to lubricate the edge of the belt since it doesn't solve the core problem. I took a square tool and it seems like the UM3 is lined up.

 

At this point I might have to send the printer in for repair unless there are other ideas.

[Torgeir 242]

Hi Xalara,

 

From the picture you have here, it seems that the (plastic) spacer height is to short (seems to be squeezed). So as the slider (holding the 6 mm axe) move toward the right side, the belt is forced to the inner edge of the pulley and wearing the belt.

 

The solution is to have a new spacer with proper length, or alternatively use a washer selected to line the belt along the upper 8 mm shaft as it is normally aligned along this shaft.

 

Good luck.

 

Regard

 

Torgeir

Edited February 3, 2020 by Torgeir
Spelling-

[geert_2 557]

15 hours ago, Torgeir said:

Hi Xalara,

 

From the picture you have here, it seems that the (plastic) spacer height is to short (seems to be squeezed). So as the slider (holding the 6 mm axe) move toward the right side, the belt is forced to the inner edge of the pulley and wearing the belt.

 

The solution is to have a new spacer with proper length, or alternatively use a washer selected to line the belt along the upper 8 mm shaft as it is normally aligned along this shaft.

 

Good luck.

 

Regard

 

Torgeir

 

Do you mean that the 8mm rod on which the pulley is mounted, could be shifting (or be shifted) axially, due to too much axial play, or an incorrect plastic spacer? Or one of the pulleys being mounted a bit too far away from the printer-housing? That could also explain the phenomena.

 

[Torgeir 242]

Hi,

 

Yes, at the moment the spacer seems to be squeezed so therefore the pulleye's position is offset the belt following the upper shaft.

 

See the attached picture.

Thanks

Torgeir

Edited February 4, 2020 by Torgeir

[Xalara 6]

Updating for anyone that stumbles on this thread in the future: I ended up sending the printer to Ultimaker to get repaired at the factory. It does indeed turn out that the pulley was originally installed backwards and they have fixed the issue by reinstalling it correctly.

 

Thank you everyone for your help.

[p-kimberley 4]

I was having this issue too: a loud rubbing/dragging noise when moving the print head along the X axis. It only occurred when the short belt was connected to the motor pulley.

 

The Australian reseller was very helpful and we isolated the problem to the short belt attached to the X stepper motor, which appeared a little worn. The printer had done around 500 hours of print time.

 

After axle calibration didn't help, the reseller shipped a replacement short belt. I fitted the new belt and re-aligned the axles - and we're back printing again, minus the noise.

 

Takeaways from this:

1. Make sure belts aren't always rubbing up against pulley edges, particularly with the short belt as the drag can cause excess wear of the rubber. Use thumb screws to adjust offsets as needed.
2. Check for axle play, as per the Ultimaker maintenance article
3. Lubricate axles to reduce drag on the motor and other moving parts (such as belts)

Edited March 7, 2020 by p-kimberley