Prusa Core One L - Persistent Ghosting and Mechanical "Clicking" from Left Motor Block
Hi everyone,
I’m reaching out to the community for help regarding my Prusa Core One L. I have been working with Prusa Support for about 2 months now, but despite numerous attempts and tests, we haven't been able to find a definitive solution to the following issues:
- Persistent Ghosting/Ringing: Highly visible on complex geometries and test models. It remains consistent regardless of software calibrations or mechanical adjustments.
- Asymmetric "Clicking/Rattling" Noise: Originating from the rear-left motor block. The noise occurs during Front-Rear, Left-Right, and diagonal movements (Front/Left - Rear/Right). It is reproducible even when moving the print head manually with motors off. I’ve also noticed that the clicking volume increases as belt tension increases.
Printer Specs:
- Model: Core One L
- Firmware: 6.5.3 (issue also present on 6.5.2)
- Filaments used: Buddy 3D PLA Black and other PLA filaments (prusa and no prusa).
Steps taken so far (under support guidance):
- Software Calibration: Multiple Input Shaper and Phase Stepping calibrations performed.
- Belt Tension: Checked and set within nominal range (92 Hz Upper / 88 Hz Lower).
- Axis Maintenance: Cleaned and lubricated Y-axis rods with Prusa lubricant.
- Pulley Troubleshooting: Swapped the motor pulleys between X and Y motors. This makes the clicking disappear temporarily (for about 48h of printing), but then it systematically returns. Grub screws are correctly tightened on the flat part of the motor shaft.
- X-axis Guide Rail: Loosened the screws, pressed the rail down, and retightened them from the outside toward the center as suggested by support.
- Slicer Profiles: Tested both "Speed" and "Structural" profiles and change speed and acceleration; ghosting remains evident, especially on faster profiles.
Video evidence and documentation:
I have compiled several videos and test files that clearly show the noise and the print defects:
- Complete Analysis (Photos, Videos and G-codes): Analysis Archive
- Click sound video (google photo link): Click video
- Ghosting Test with Buddy 3D PLA Black - HF nozzle 0.4 - 0.25 lyaer height - speed profile
Has anyone else encountered similar issues with a Core One L? The fact that the noise returns shortly after reseating the pulleys makes me wonder if there's a defect in the motor itself or an internal bearing in the left block.
Any advice or insight would be greatly appreciated. Thanks!
RE: Prusa Core One L - Persistent Ghosting and Mechanical "Clicking" from Left Motor Block
Could you also upload the .3mf file which produces the ghosting print to your Google drive please?
RE: Prusa Core One L - Persistent Ghosting and Mechanical "Clicking" from Left Motor Block
Sure,
I add the .3mf project. Ghosting Test project
Thanks
RE: Prusa Core One L - Persistent Ghosting and Mechanical "Clicking" from Left Motor Block
Thanks!
It is a bit hard to see from the photo how pronounced the overshoots (ringing) actually are. A lot of the contrast is from the filament becoming glossy (deeper black) when printed slowly, while it remains matte black during the faster stretches, I think. Where does the light actually come from in that photo? Do the bright lines represent areas where the filament bulges outward?
If you suspect that the clicking (which you seem to have isolated to one motor) is related to the ringing: You could try turning the test object to +- 45° angles, such that the quick steps during the print align with movements of only one motor or the other. Does that give a pronounced change in the ringing? If so, the two observations may indeed be related.
There have been a few reports in the Core One forum section about idlers making clicking noises. Some users have replaced the idlers; some have reported that they replaced the shafts on which the idlers sat. (The Core One simply uses screws for those, not proper shafts with a smooth section that exactly fits the ball bearing in the idler. I assume it's the same in the L?) See this thread: https://forum.prusa3d.com/forum/prusa-core-one-hardware-firmware-and-software-help/new-c1kit-strange-clicking-rattle-noise-from-y-axis-stepper-area/
But I am not sure what to recommend to you regarding the idlers. Replacing them all just to eliminate this possibility is time-consuming, and your printer is probably still under warranty? Maybe best to get back to Prusa support, if you have not discussed this specific potential cause with them yet.
RE: Prusa Core One L - Persistent Ghosting and Mechanical "Clicking" from Left Motor Block
This ghosting looks more like a too low temperature or major print speed difference. Try quality preset, or decrease the speed for the perimeters - in the sliced view look at the speed and volumetric speed if they match around the text and out of text areas.
See my GitHub and printables.com for some 3d stuff that you may like.
RE:
Hi everyone, thank you for the feedback. Here are the answers to your questions and an update on the tests I’m performing:
Surface Finish and Visuals:
To answer @jurgen-7 regarding the lighting and overshoots
It is a bit hard to see from the photo how pronounced the overshoots (ringing) actually are. A lot of the contrast is from the filament becoming glossy (deeper black) when printed slowly, while it remains matte black during the faster stretches, I think. Where does the light actually come from in that photo? Do the bright lines represent areas where the filament bulges outward?
The photo was taken under a ceiling LED lamp located directly above the objects. I checked the surface with my fingernail and didn't feel any significant layer shifts or physical ridges between the matte and glossy areas; it seems to be purely a surface finish issue.
I’m curious to know if this is the standard result to expect from a Core One L or if the finish should be perfectly uniform.
To answer @_kaszpir_ regarding the profiles and speeds:
This ghosting looks more like a too low temperature or major print speed difference. Try quality preset, or decrease the speed for the perimeters - in the sliced view look at the speed and volumetric speed if they match around the text and out of text areas.
I tried the Structural preset, and while the surface finish becomes uniform, it introduces a lot of VFA (Vertical Fine Artifacts). With the Balanced preset, the result is unfortunately identical to the Speed profile (the matte/glossy inconsistency persists).
I found the "Volumetric flow rate" view in the slicer preview. The flow changes I see in the slicer are partialy aligned with the matte/glossy visual effects on the printed object. It seems the speed changes around the text areas are probably causing the finish issues. How can I fix this issue? (I'm not a PrusaSlicer expert, as you may have noticed! 😊 ) I'd love to know if there's a way to keep the flow more consistent around those feature areas.
Mechanical Checks:
To answer @jurgen-7 regarding click/surface quality correlation:
If you suspect that the clicking (which you seem to have isolated to one motor) is related to the ringing: You could try turning the test object to +- 45° angles, such that the quick steps during the print align with movements of only one motor or the other. Does that give a pronounced change in the ringing? If so, the two observations may indeed be related.
I finished the 45° rotation test, but the result is identical to the previous prints. The ringing/finish issues remain unchanged despite the different orientation. Maybe the 2 things are not correlated.
There have been a few reports in the Core One forum section about idlers making clicking noises. Some users have replaced the idlers; some have reported that they replaced the shafts on which the idlers sat. (The Core One simply uses screws for those, not proper shafts with a smooth section that exactly fits the ball bearing in the idler. I assume it's the same in the L?) See this thread: https://forum.prusa3d.com/forum/prusa-core-one-hardware-firmware-and-software-help/new-c1kit-strange-clicking-rattle-noise-from-y-axis-stepper-area/
But I am not sure what to recommend to you regarding the idlers. Replacing them all just to eliminate this possibility is time-consuming, and your printer is probably still under warranty? Maybe best to get back to Prusa support, if you have not discussed this specific potential cause with them yet.
Regarding the idlers, I tried placing my finger on them during manual movements. While I can hear the "click," I don't feel any vibration coming from the two idlers on the left motor block. My initial discussion with Prusa support actually started with the "faulty idlers" hypothesis, but they then shifted the focus toward the motor pulleys and the gantry.
Thanks!