Mk3S - Noisy Print Fan - Questions & Feedback...
Hey everyone,
I've had my i3 Mk3S for a couple of months now and am consistently impressed by the print quality. As my experience grows and I've got that dialled in, I want to turn my attention to resolving some really (*really*) annoying issues - and would appreciate any help or guidance the community would care to give...
First issue is the angled print fan on the hot end. for reasons I don't pretend to understand, this fan is stupidly, stupidly noisy. Best way to describe it would be to say that it has a "death rattle" when its running. I know this isn't a smart thing to do... but if you use a fingertip to gently press on the centre of the fan and reduce it to a near-complete stop, the entire printer becomes silent - it's generating *that* much noise. So: first question - is this common? Is there a set of checks or procedures I can run to see if I can get my fan to quieten down?
Second issue is that although I have (today) ordered a replacement print fan... looking at the assembly mechanism and the fact that the cable for the print fan has to be "dis-entangled" from the main cable routing back to the Einsy board... I'm starting to think that it might be a *lot* easier to cut the cable to the existing fan [as close to the fan as possible] and then solder or crimp a 3-pin socket to the end of that cable and trim back and solder a plug on the replacement fan when it turns up. This should in theory give me the ability to relatively easily swap my print fan in future, should the replacement fail as quickly as this one has... I wonder if anyone has tried anything like this - and if so, what their experience was?
Third issue is likely nothing more than a thought for anyone from Prusa surfing these forums: why not simply get a multi-way connector and run a single multi-way cable to the print head? It might make the mechanism a bit more reliable - and it would certainly make it *much* easier to maintain...
Obviously I'm asking some fairly narrow questions here, because this *seems* like the best way to go about the process of replacing the print fan. However, if anyone has come up with a neater solution, I'd be grateful for guidance.
Thanks in advance.
Best Answer by JoanTabb:
Hi Ytene,
If you undo the two screws retaining your print fan, you should find a label on the rear of the fan.
if you peel this label back it should reveal a hole in the middle of the housing.
Drop a little light oil, say sewing machine oil. into this hole, replace the label and refit the fan, you should find that it runs quietly once more, and you should have peace and quiet whilst you await the supply of your new fan.
I have had similar issues and on my Mk2... which admittedly has 12 volt fans with no feedback, I did source some fans with Ball bearings instead of plain bearings.
I bought two, and so far the first replacement is still running... about 4 years after I fitted it.
I have spares for My Mk3. but to be honest I don't recall whether I actually sources ball bearing versions with tacho feedback.
So far, neither of my Mk3's have needed new fans. (Fingers crossed they don't fail now...)
regards Joan
RE: Mk3S - Noisy Print Fan - Questions & Feedback...
Hi Ytene,
If you undo the two screws retaining your print fan, you should find a label on the rear of the fan.
if you peel this label back it should reveal a hole in the middle of the housing.
Drop a little light oil, say sewing machine oil. into this hole, replace the label and refit the fan, you should find that it runs quietly once more, and you should have peace and quiet whilst you await the supply of your new fan.
I have had similar issues and on my Mk2... which admittedly has 12 volt fans with no feedback, I did source some fans with Ball bearings instead of plain bearings.
I bought two, and so far the first replacement is still running... about 4 years after I fitted it.
I have spares for My Mk3. but to be honest I don't recall whether I actually sources ball bearing versions with tacho feedback.
So far, neither of my Mk3's have needed new fans. (Fingers crossed they don't fail now...)
regards Joan
I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK
RE: Mk3S - Noisy Print Fan - Questions & Feedback...
@joantabb
Brilliant advice - thank you! Sewing machine oil duly ordered....
RE: Mk3S - Noisy Print Fan - Questions & Feedback...
Quick update for anyone who finds their way to this thread and is interested...
I ordered a small vial of Singer Sewing machine oil from Amazon [not the cheapest, but a reputation for strong quality] and followed Joan's directions. The process was pretty straightforward, but I did find that the small adhesive label on the underside of the fan did not want to stick back down after being carefully peeled back, so I improvised with a small length of electrical tape.
The results are "night and day" and noise from the printer has been virtually eliminated.
Very happy with that!
Thank you Joan...
RE: Mk3S - Noisy Print Fan - Questions & Feedback...
Hi all,
I have the same part cooling fan issue - ridiculously noisy for the thing it is. Tried the oil and did nothing. I am suspecting that it's a PWM frequency problem rather than a fan problem. The fan is noisy when running at 20%; if I stop the fan with a finger, the case still hums at that same frequency - so it's not mechanical. Fan at 100% is quiet - just air wooshing. Video attached. This seems to be a very common and very annoying problem; Prusa, any ideas? Anybody else? Thanks.
RE: Mk3S - Noisy Print Fan - Questions & Feedback...
Hello Fabio,
did you manage to solve your problem? I have the same problem as you.
Prusa says it's normal but I have 3 printers and only lastly bought (3 weeks ago) has this problem. How to believe them in this case ....
RE: Mk3S - Noisy Print Fan - Questions & Feedback...
I have read that the bearings in these fans are not designed to run at an angle as they are positioned in the Prusa, and that this will shorten their life and lead to noise. You can do the "Delta P" fan shroud mod which will position the fan vertically, improve visibility under the fan shroud, and probably also improve part cooling. It is also one of those rare extruder modifications which doesn't require major disassembly and rewiring to accomplish.
RE: Mk3S - Noisy Print Fan - Questions & Feedback...
I have exactly the same problem, the same noise. Recently assembled Mk3S+ kit, it is working flawlessly, except for that annoying rattle in the fan. Just logging it here for Prusa, as I do not have a solution, but would love to hear from others. IMG_1748
RE: Mk3S - Noisy Print Fan - Questions & Feedback...
This is a user to user forum so not monitored by Prusa.
If your printer is under warranty you can login to your eshop account and click on the tech support chat button on the lower right of the page. If you don’t see it you may need to temporarily disable any ad blockers.
Fwiw, the fan noise in your video almost sounds as if one of the blades is lightly touching something. Try touching the fan housing in different places and putting pressure on it to see if the sound changes. You may be able to open it up and tweak the way the fan sits in the housing to stop the rubbing.
Just a thought, I could be way off base. Hard to tell from the video.
Cheers
I have exactly the same problem, the same noise. Recently assembled Mk3S+ kit, it is working flawlessly, except for that annoying rattle in the fan. Just logging it here for Prusa, as I do not have a solution, but would love to hear from others. IMG_1748
RE: Mk3S - Noisy Print Fan - Questions & Feedback...
As I mentioned in my original post, the noise is NOT mechanical. If I stop the blade with a finger, the noise persists, and the fan is completely quiet at full speed. That's why I am baffled by it, and why opening the fan, lubricating the bearings or changing the duct geometry is not helping. I think it has to do with the PWM frequency of the fan driver, but we need Prusa to look into this.
RE: Mk3S - Noisy Print Fan - Questions & Feedback...
@fabio - apologies if I was unclear, my response was to the previous poster @doubledutch
RE: Mk3S - Noisy Print Fan - Questions & Feedback...
@RandyM9 and @Fabio, thanks both for your input. I agree with Fabio, it is not necessarily mechanical, as it does not happen at full speed, and is still audible when stop the fan with your finger. I did get in touch with Prusa support and they are sending a replacement fan. I will grease the bearings thoroughly before installing and keep my fingers crossed.
RE: Mk3S - Noisy Print Fan - Questions & Feedback...
@RandyM9: Sorry, I didn't mean to be pointy; thank you for your advice. The noise in Doubledutch's video is exactly the same I experience, so I assume we are dealing with the same problem.
@Doubledutch: Great! At least it's a step forward; please let us know how it goes after replacement.
RE: Mk3S - Noisy Print Fan - Questions & Feedback...
@fabio - thanks, no worries, we’re good.