Layer shifts/clunking after 3.2H upgrade
Hey folks,
I've had my RR 3.1 running great for years with a few minor upgrades; I was running stock + EBB42 toolhead board and dual (extrusion-less) linear rail. It's been rock solid.
Recently a stepper motor died on me so I decided to upgrade to 3.2H since it came out recently. I switched from EVA to the RR toolhead with beacon and went back to using the original 2020 extrusion gantry (as the extrusion-less upgrade doesn't fit the new joiner printed parts).
I've been tinkering with it for weeks now thinking that the poor prints I'm getting are just down to tuning for the new toolhead setup, but I'm convinced I've got mechanical issues. I've had the gantry stripped back (I even tried it with a modified extrusion-less setup in case my original gantry was trash) and I've rebuilt the stepper motor housings from the ground up. I've tried various belt tensions and rebuilt the toolhead checking everything is tight. I've tried with and without the hybrid belts in place - same issues all the time.
I'm at a total loss now, I can't get a nice print from it at all -- the main issues are with infill and parts of the perimeters being oddly wavy which I think is tiny layer shifts and I get bigger layer shifts if I let it print on for longer.
There is also a bit of a clunk when it changes x direction as demonstrated in this video:
https://youtu.be/4I9GxOIwPR4
I get the same issues with PETG and ABS. I've tweaked pressure advance, flow rate, line width, retraction, temperature -- I'm ready to throw it out the window and I'm considering downgrading back to 3.1.
If anyone has any thoughts/ideas of what I could try next I'm all ears 🙏
16 Replies
The clunks are bo bueno, find where that's coming from. For the extrusion troubles, triple check that you've got a 0.4 and not a 0.6, somehow several people have had the "wrong" one on without realizing.
Thanks for the suggestion, I’ve checked my slicer and printer configuration are all 0.4 nozzles. I did have the thought to try a 0.6 nozzle in it as it’s a new nozzle (my 0.4 that came with my rapido is not a volcano nozzle) so may be duff? It’s from the mellow store on AliExpress I’ve had other stuff from them and it’s been ok. I also measured extrusion and it was correct.
The clunking I just can’t pin down, I’m back to dismantling the motor housings and joiners again 😩 I’ve never been so frustrated with the thing!
I’ve also swapped one of my y rails that felt a little less smooth than the other one so maybe there’s something there. The gantry and tool head move as freely as I can remember them ever moving without belts on though, no noticeable binding
Double check your toothed pulley on your motor. I am currently chasing down a similar symptom and I found that one of my motor pulleys does not rest concentrically with the motor shaft. This is further evidenced due to wear marks on the motor shaft, where the top of the pulley rests. I’ve already replaced the pulley with no luck and am currently waiting for a new motor as i suspect the tolerance between the pulley and shaft may have been too large.
Interesting - I’ve swapped my hybrid pulleys (the new ones from my kit) for my corexy pulleys (the original ones I had on) as part of my latest rebuild. I haven’t tried printing with it yet but I had a bit of belt walk going on that seems to have gone now so I’m hoping that’s a good sign… I’ll try it out with a print tomorrow
Example of my issue and suspected cause ^
Ah I see, I’ll double check that on mine. One thing I did notice is that the hybrid pulleys fitted very snug on the shafts whereas my original pulleys slide on much more loosely. Your print issues definitely look familiar with the wavy perimeters.
Step in the right direction today; I actually got something printed! my wobbly perimeter issue seems to have largely gone away after the last rebuild; I just need to get to the bottom of the crappy solid infill I'm seeing. I've tried tweaking various settings with no luck as of yet. On the print in the video I also had a layer shift randomly near the end I need to figure out, I've tightened my belts a little and I'm trying again
So I'm still struggling with this. Its not as bad as it was after doing a bit of a strip down/rebuild of gantry and various pulleys checking alignments and tension etc but the naff solid infill is still an issue. I also have some VFAs that appear to get further apart the faster I print and straight perimeters in some directions have a 'wobble'. I'm running out of ideas on what to change/try and fix if anyone has any suggestions 😞
I too still struggle with this same exact issue. I will be counting my belt teeth next to make sure they are exactly the same, then using gyats to tension. Hoping to see improved results. Have you by chance verified your tooth count on x y belts?
It turned out I had set my input shaper frequencies to my acceleration values and that caused all my problems 😅 a frequency of ~13k and ~7k makes for bizarre issues it seems!
Can you send me an example of your corrected input shaper config? Need to verify against my own.
[input_shaper]
shaper_freq_x: 62.8
shaper_type_x: mzv
shaper_freq_y: 39.8
shaper_type_y: mzv