"Oink-oink" grinding noise from extruder on retraction with my new Prusa MINI. Gears to tight or lose, or what?
Please see this video:
It seems like the gears are either too loose or too tight. Anyone have good experience with this? I've seen several suggestions on pushing the gears together when tightening the extruder motor, but I'm afraid this may introduce prematurely wear on the gears.
I followed the manual, and installed the stepper motor before the gear, and it dropped nicely in, and seemed tight enough, but had some slack in the bearing. After assembling with both bearings, everything seemed fine, but I got that noise.
Retractions etc. works as they should. No noticeable stringing this far. But I get that "oink-oink" sound, that's very annoying, considering how silent this printer is.
I tried pushing them more together, and adding ceramic grease, but it's still the same. Is the filament sensor adding too much drag?
My experience tells me that the noise in the video means that the gears are too tight. But I guess there will be more "clicking" if they're further apart.
It's annoying that so much has to be disassembled to test, but I guess I'll just have to. I'd rather have a bit of slack + grease to deal with the gear backlash when moving direction, rather than having them bind to each other when too close.
Thoughts?
RE: "Oink-oink" grinding noise from extruder on retraction with my new Prusa MINI. Gears to tight or lose, or what?
Either my hearing is bad or that sounds fairly normal.
I even have my hearing aids in and I do not hear it.
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Chuck H
3D Printer Review Blog
RE: "Oink-oink" grinding noise from extruder on retraction with my new Prusa MINI. Gears to tight or lose, or what?
Either my hearing is bad or that sounds fairly normal.
I even have my hearing aids in and I do not hear it.
It’s very apparent from 00:02-00:03, a scratching noise when the gear is moving quickly back and forth (retraction).
It is much louder IRL though. It’s annoying because it’s the only noise the printer makes.
RE: "Oink-oink" grinding noise from extruder on retraction with my new Prusa MINI. Gears to tight or lose, or what?
@glenn-4
You could always send that video to chat support. My computer does not like your video and keeps starting and stopping. I could be missing part of the video trying to get it to plat correctly.
It could be grinding filament if the idler is too right. I would start by disassembling the extruder and see if there are any grind marks. Check the filament for the same. If the marks are on the housing, you could have warping or a defect in the parts. If you have to grinding on the filament, your idler is too tight.
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Chuck H
3D Printer Review Blog
RE: "Oink-oink" grinding noise from extruder on retraction with my new Prusa MINI. Gears to tight or lose, or what?
There are no grind marks and no issues with the filament. It never skips on the filament. No shavings etc. I guess the two gears might be slightly binding to each other. I’ll try to move them apart and add more grease.
RE: "Oink-oink" grinding noise from extruder on retraction with my new Prusa MINI. Gears to tight or lose, or what?
Okey, I’ve figured it out;
If your extruder gears (not filament related) has a grinding/whirring/“oink” sound when retracting, it’s because the stepper gear and the filament driver is too close together. The teeth are binding, and it will cause wear over time.
If you have a clicking/tick-tock/tapping noise on retraction, it’s just because the gears are slightly apart from each other. It’s a microscopic backlash when the gear is changing direction and engaging with teeth in the opposite way. Quick retraction will make some tick-tock sounds. This is more desirable, as it’s only a noise, the gears are free from each other, not grinding. You can add some grease to lower the “click” sound, but it will probably come back.
You can in the last case try to move them SLIGHTLY more together, and get a much lower tick-tock noise, but it’s hard to find the sweet spot where it doesn’t tick loudly, and doesn’t grind.
But mechanically; grinding = bad, slight tick = OK.
RE: "Oink-oink" grinding noise from extruder on retraction with my new Prusa MINI. Gears to tight or lose, or what?
I reassembled the extruder, and made sure to push the gears slightly away from each other, and then I cleaned and reapplied with some thicker grease that made the clicking go away. MUCH more silent now. 