Is my stepper motor failing?
Started making these sounds in the middle of the print. It kept extruding though, didn't stop or something. The stepper motor isn't that old, but wasn't expensive either. Anyone knows this sound?
Unlikely that it's the stepper. It sounds like something's scraping. I heard similar noises after inconsistent extrusion on infill, so that the infill was standing up a little bit and the print head was scraping over it.
Could also be ball bearings or something else in there that's scraping over something. It is most likely something connected to the motion.
I've checked the print it was working on and changed the Z-offset, had no influence on these scraping sounds. It's definitely somehow connected to the extrusion, that's why I assumed it to be the stepper.
Do you think those really tiny bearings used for the extruder axis' can make such a sound? Other than that I'm really out of ideas outside basically sanding down anything that could be the problem… I even made sure to print the whole MK4 extruder you see in the video on the Prusa MK4S of my local hackspace to make sure it has perfect dimensional correctness etc.
Do you think those really tiny bearings used for the extruder axis’ can make such a sound?
Absolutely, yes. If it never made that sound and started with age, do not go sanding anything. Clean and lubricate again and look for broken parts.
Any point of contact can be making that noise. Including the motor, yes, but everything else is more likely.
In the middle of the print change the flow modifier to 0%.
That will turn off the extruder while leaving everything else as-is.
I suspect it's the X or Z bearings.
Please don't sand anything. If your problem is wear, adding wear will not help.
Another thing you can do is move the print head up, and while not printing anything just extrude 100mm of filament. Then you will only hear the extruder.
The only thing in the extruder that I would expect to make a noise like that would be if it's a geared extruder with seriously abused gears that are slipping. But then you'd see extrusion problems.
In general, the extrusion motor should be way to slow to create such high-frequency noises, unless your motor control is seriously wrong setup.
Unplug the motor to see if there is a difference
You sure you didn't get an agitated cicada stuck in there?
Seriously, though. It could be the stepper or even just a cooling fan.
It's no fan, I checked that. Also definitely comes from the extruder assembly, I could slightly manipulate it if I was pushing on the filament from above.
Then worn bearings on the extruder gears, or a gear chipped.
It definitely sounds like a fan scraping on something. it also seems to be triggered by the print head changing direction, but only briefly as it jerks. Have you checked fan bearings in the hotend and part cooling? Or just something as simple as parts being tightened properly?
Welp, it was one of the tiny ball bearings of the extruder gear axle.
sounds like the air scoop is scraping on tbe print
steppers work or they don't. Likely a fan blade hitting something.
UPDATE:
It apparently was a damaged ball bearing. Upon opening the extruder once again I found some black grease littered around one of the tiny bearings that're supporting the extruder gear axle. Replacing them solved the issue, many hours of printing with no angry cicada in my printer anymore.
Would've never expected such a tiny thing to make this much ruckus.