Question Z-wobble, but only with some models?

[frodo5343]

Printer Model

Voron 2.4

Extruder Type

Clockwork 2

Cooling Type

Stealthburner

Hello all,

I upgraded several months ago to tap and stealthburner and have been having intermittent issues since.

I first noticed it with this model. https://1drv.ms/i/s!As3BjAMCoBAWi84sMYw1ZXiPRIMIGw?e=nRuwe5


I printed a bunch of these and the z-wobble issues weren't exactly in the same pattern every time, so I don't think it's a z-belt or z-rail issue.

I did a bunch of testing and what I noticed is that if the model is simple, the prints come out perfect, but if the model is more complex I get issues. Note how when I put embossed text into the model I get an ugly print, but the one without text looks great. That's been reproducible across many test prints.



Benchy and cube for reference








It just really makes some of my prints look terrible:



I thought maybe it was belt tension, so I double checked my belts to make sure they were good.

I thought maybe I had something loose, so I checked any bolts I could get to and felt around to see if anything was loose.

I thought maybe it was inconsistent diameter of the filament, so I switched filaments and had the same issue.

I thought it could be a pressure advance issue, so I re-tuned PA and that didn't fix the issue.

I tried slowing the print down, and it helped a bit, but not much.

I tried cutting all my acceleration speeds in half thinking maybe I'm skipping steps and that didn't seem to help.

The other (maybe unrelated issue) I noticed is that in a model I recently printed I'm getting gaps? That seemed to get better with a higher print temp though.



I'm really kind of stumped at this point....

Any suggestions would be much appreciated!

Thanks for wading through all this!
Matt

 

[frodo5343]

Just to update this. Here is an example where the simple part of the print printed ok, but the more complex portion looks terrible.



I think I'm actually dropping steps based on looking closer.




The head moves just fine, so I'm not sure why I'd drop steps, especially since I did tests where I cut all my accelerations in half and I'm using the default prusaslicer profile.

I did notice some wear on my belts, so I'm going to replace the belts. I'm also going to replace the front idlers with the Ramalama idlers (then replace these parts if I hopefully get the prints looking better). We'll see if this helps....

 

[ajaytanna]

I faced similar issue on another bed-slinger printer and found it happening even though the bed was firm and steady. Turned out the X axis needed tightening. In your case I would check TAP and the entire SB assembly for unintended displacement. The whole toolhead has several potential places to go loose. Also the X and Y rail end points and their carriage blocks. Lastly change slicer to maybe ORCA Slicer since its close to Prusa. (It's really great BTW)

 

[frodo5343]

I faced similar issue on another bed-slinger printer and found it happening even though the bed was firm and steady. Turned out the X axis needed tightening. In your case I would check TAP and the entire SB assembly for unintended displacement. The whole toolhead has several potential places to go loose. Also the X and Y rail end points and their carriage blocks. Lastly change slicer to maybe ORCA Slicer since its close to Prusa. (It's really great BTW)

Thanks for the suggestion. I ordered a cnc tap to install when I replace my belts so I'll see if that helps too