Deflecting X-Axis belt at right side pulley
 
Notifications
Clear all

Deflecting X-Axis belt at right side pulley  

  RSS
Ira S
(@ira-s)
Trusted Member
Deflecting X-Axis belt at right side pulley

Just finished building the MK3. Went through pre-check, calibration and printed a nice Prusa Logo. All is good.

But what I did notice is the behavior of the X-Axis belt at the right side pulley. Each time the print head changes direction, the belt right near the pulley tilts either up or down a little. Moving left it tilts down (both belt sections) and moving right it tilts up. The pulley itself doesn't change angle at all and moves freely. Doesn't matter whether the print head is all the way to the left, centered, or toward the right side. The belt tension is good - at least it's not loose - and I don't think it's too tight.

While it doesn't seem to effect printing (at least not yet - only did one print), it does seem weird.

Is this normal?

Posted : 01/03/2018 10:33 pm
llj3663
(@llj3663)
Eminent Member
Re: Deflecting X-Axis belt at right side pulley

What revision are your printed parts? If they are pre-R2 (mine were B3 I think) there's a slight misalignment that causes this. It was really bad on my as well. I actually just swapped the updated parts in last night, haven't printed anything yet.

The main issues (at least from what I could tell) are:

- excessive wear on the belt, literally shredding the belt and getting powderized belt everywhere
- false-alarms with crash detection enabled (not sure if this was actually the cause or not for this one).

Posted : 01/03/2018 10:39 pm
Ira S
(@ira-s)
Trusted Member
Topic starter answered:
Re: Deflecting X-Axis belt at right side pulley

Version of the right side part is B6 I believe - difficult to see. Kit shipped 2/22.

Posted : 01/03/2018 11:44 pm
william.o6
(@william-o6)
Active Member
Re: Deflecting X-Axis belt at right side pulley

Having the same issue, I have tightened the belt and the pully but still getting this and I am guessing it is what is causing the layer shifts in some of my prints, I guess I'll try the new parts.

Posted : 02/03/2018 12:34 am
gustavo.s2
(@gustavo-s2)
Eminent Member
Re: Deflecting X-Axis belt at right side pulley

B6 are the R2 parts printed on the prusa farm

https://shop.prusa3d.com/forum/original-prusa-i3-mk3-f30/new-printed-parts-version-r2-b6-t14551.html

Posted : 02/03/2018 6:26 am
llj3663
(@llj3663)
Eminent Member
Re: Deflecting X-Axis belt at right side pulley

Huh didn't realize they had different numbers (B6 vs R2) for the printer farm parts. Makes sense.

Anyway I put the x-axis back together and tested it by manually moving the extruder carriage back and forth and it seems like the R2 parts fixed the belt deflection issue for me. I'll get the rest of the my printer back together and actually test it with a print to see if the issue is fully resolved.

Posted : 02/03/2018 4:02 pm
lowboydrvr
(@lowboydrvr)
Eminent Member
Re: Deflecting X-Axis belt at right side pulley


Huh didn't realize they had different numbers (B6 vs R2) for the printer farm parts. Makes sense.

R2 are the parts posted on line for self-printing. B6 are the parts that Prusa actually prints in their farm. It's the same parts. This way Prusa can tell if the part was printed by them or "at home".

Posted : 02/03/2018 5:42 pm
Tiago
(@tiago)
Reputable Member
Re: Deflecting X-Axis belt at right side pulley

I had this with pre R2 parts, printed R2 parts it got lot better, still the tilt is there but much minor. I think they are not on the point yet

Posted : 02/03/2018 6:10 pm
llj3663
(@llj3663)
Eminent Member
Re: Deflecting X-Axis belt at right side pulley

Just wanted to post a follow up after I got my printer fully operational. Looks like the R2 parts fixed the twisting belt issue.

I'm in the same boat as tiago.c in that there's still a very minor tilt, but I'm going to assume that this is due to the belt being deformed by the earlier versions of the printed parts.

Posted : 04/03/2018 1:20 am
jonathan.h2
(@jonathan-h2)
New Member
Re: Deflecting X-Axis belt at right side pulley

I'm having the same issue with my mk2 turned mk2s turned mk2.5. Does anyone know if the current mk2 generation part has been updated with this fix, or whether the mk3 part is usable in a mk2.5? Thanks.

Posted : 23/05/2018 6:44 pm
Share: