MK4 Squeaky Extruder
I made a Prusa MK4 from a kit I received this year; late January, 2024. I have been enjoying the printer quite a bit, and have gotten over 6 days of print time in. However I've noticed the extruder can often be quite noisy with what can best be described as a high pitched squeaky grind.
It is my understanding that mid last year there were some MK4s sent out with faulty extruder motors, but it's also my understanding that the issue has since been corrected and I should expect that my kit mailed this year would have a newer motor.
I've read incorrect Idler tension could be a culprit, along with issues described here:
https://help.prusa3d.com/article/extruder-noises_2013
The Hotend assembly seems installed correctly. I don't notice any odd noises when extruding with the E-Axis. Please advise. Thanks!
RE:
RE: MK4 Squeaky Extruder
Does it make this odd (very odd indeed) noise when the extruder is moving only on the x-axis?
RE: MK4 Squeaky Extruder
No, it is not restricted to one axis. However I think I have narrowed it down to PETG extruding. I've tried bumping up the temperature of PETG printing to 250c, but the noise remains. Slowing the print to 70% speed helps with the noise somewhat.
RE: MK4 Squeaky Extruder
Hi,
I'm having the exact sound issue here on my MK4, also a kit from end of Dez./early January. It occurs also on PETG, but I only printed the first few days in PLA, since then PETG, so I will have to try this with PLA maybe the next days.
For me, it only occurs on fast moves, usually IS sliced models, so it never is an issue on the first layer for example - fast paced long lines on the other hand, it rattles like your mp3. I'm just not sure if it is the extruder (due to fast gripping/extruding the petg or a gear issues with not enough grease combined with high speed use) or if it could be PETG on PETG and a strange way of squeaking. Given all 4 possible directions with x/y, I had cases, where it only makes this sound in 1 out of the 4 possible directions (brim of a box), so it could be some residue on my nozzle colliding with the last layer of PETG and the residue is only applied on one "corner" or side of my nozzle.
RE: MK4 Squeaky Extruder
Has anyone had a fix for this? Mine just started squeaking and I've been using it since January '24 with no issues. Lube the gears somewhere or something? I'm guessing it's just maintenance, but I'm not sure which part of the hot end to target.
RE: MK4 Squeaky Extruder
Update: I changed filament and it went away, so in my case it looks filament-specific. Thank you
RE: MK4 Squeaky Extruder
Update: I installed the upgrade to the MK4S and it's squeaking again. I thought the idler was too tight, but loosening it didn't help. Any insight or fixes that anyone has been able to implement are appreciated. Thank you
RE: MK4 Squeaky Extruder
I upgraded 6 Mk4 to Mk4S. I am running PLA from Push Plastic. No squeaking before upgrade. One of these machines is squeaking loudly on every print. Video is attached. Any suggestions are appreciated!
Bret
RE: MK4 Squeaky Extruder
I'm almost certain that the problem is electrical and not mechanical, from a mechanical point of view I've tried everything, all I have to do is try a fake print, without filament, I think a small piece of filament inserted into the bushing without letting it extrude and see is enough. if it still squeaks, I definitely think it is a problem with the extruder pankake, particularly at high speed and when it has to make fast and frequent retractions, I will make a report as soon as I manage to do this vacuum printing to definitively exclude that it is a mechanical problem
RE: MK4 Squeaky Extruder
I disassembled the extruder and found the thin, 5mm ID washer/spacer/bushing that is between the stepper motor and the gear box was scraped. The fitment is against the inner race of the bearing in the gearbox. The inner race should be fixed or at least not rotate around the shaft or scrape the washer. I replaced the washer and applied a light coating of lube on both sides. It's been printing parts for maybe 30 hours since then with no squeaks. Is the lube letting the inner race continue to rotate? Will it wear out and start again? Is this a bearing defect or a bearing with too much internal resistance such that it was easier for the stepper motor to spin both races of the bearing around the shaft like a plain sleeve bearing? If it squeaks again, I'll update this thread.
RE: MK4 Squeaky Extruder
I have the exact same noise that started after my MK4 to MK4s upgrade as well. It's definitely coming from the extruder. Based on your finding, I'll have to take the extruder apart again to see if I have the same washer scraping or something else scraping. Thanks for your solution.
RE: MK4 Squeaky Extruder
The good news is that the noise is narrowed down to the extruder. I was printing happily and silently with my new (4 mos. old) MK4S, when the scritchy squeeking started. I lubed all the bearings and finally narrowed the noise to the nextruder. While fiddling, I realized that my filament (Fillamentum CPE) had cross threaded on the spool, in spite of my carefulness, and it was taking some force for the nextruder to pull it off. When I pulled enough filament off the spool by hand so that the nextruder had no effort feeding the loose loop, the squeaking stopped after a few seconds. I pulled the filament loose for the rest of the print and no squeak. So I guess that the bearing for the planetary gears or the washer mentioned above is the culprit. Otherwise - awesome printer.
RE: MK4 Squeaky Extruder
I came to ask about squeaky extruder to find this 🙂 Good tips, I have MK4S upgrade planned for the weekend, and I will also check the filament, since it feels like it started with specific one... So lets see 🙂
RE: MK4 Squeaky Extruder
So for me, it seems to be filament problem. Prusament PETG Ultramarine Blue prints squeaky. And also I had some troubles with plate adhesion. Might be related.
RE: MK4 Squeaky Extruder
I tried multiple PLA filaments from 3 suppliers: Prusament, Hatchbox, and Push Plastic. The squeak didn't stop until I replaced the motor spacer washer with a new, greased washer. Surprised to hear you are having adhesion issues. I have run a little bit of PETG and many hours of PLA. The Mk4 and now Mk4S models have been flawless on adhesion issues. I do perform an alcohol wipe with different part files or if a printer is idle for any amount of time. I usually run multiple parts over a few days so between these, there's been no need to wipe. I use this bottle from Amazon ASIN B07ZZD923S for alcohol with paper towels to make the wipe easy enough that I don't skip doing it.
RE: MK4 Squeaky Extruder
Started having same problem. What washer did you use?
RE: MK4 Squeaky Extruder
Found it. It's generic 5x10x0.1
RE: MK4 Squeaky Extruder
My update: i did the upgrade to MK4S. During that, I checked between the E-motor and the first part, I think that's where is the washer. There are two spaces which shelter move on top of each other. I didn't see any wear, but I lightly lubed it and put back together. I haven't heard a squeak since.
Note, that with the upgrade, you also get injection moulded top cover, which has different design (doesn't have the white plastic spacer). And there might be different mounting pressure.
But that's how it is for me currently 😁
RE: MK4 Squeaky Extruder
The squeak is back. Strangely, it seems to be with PETG only (any)... Might it be elsewhere then the washer? Does the extruder work harder with PETG over PLA?