Y carriage noise?
I've assembled an mks+ kit and gotten through the self test and initial calibration with no issues. I've also had a couple of successful prints -- a benchy in petg and a 3.5 hour custom model print in pla. No complaints about print quality so far. But when the y axis moves past a specific area, the printer makes a strange noise. Not loud enough to be disturbing in the same room, but it doesn't sound great and only happens when the y axis moves in the particular area shown in the video. Any help figuring out what's causing it and/or telling me it's nothing to worry about would be much appreciated!
https://forum.prusa3d.com/wp-content/uploads/2021/03/20210329_174207.mp4
RE: Y carriage noise?
It doesn't sound too bad, it might just be a resonance symptom but first check:
Is something loose and rattling?
Do the axes move smoothly when pushed, slowly, by hand?
If not check the smooth rods, are they dry, dirty or sticky - if so clean and lubricate.
If problem persists check the print bed mountings are not overtight - see build manual.
Do the belts make a very low musical note when plucked?
Print a belt tension checker - Prusa's own tool.
https://www.prusaprinters.org/prints/46639-tension-meter-for-the-gt2-belts-of-i3-mk3s-or-prus
Are the belts running straight on the pulleys?
Are the idler pulleys straight?
...and to check resonance move the printer to a different surface, the floor will do for an hour, make a test print. If the sound goes away then you are getting resonance between your printer and the surface it was standing on, either find a new site for the printer or search for resonance on here and take some of the measures advocated.
RE: Y carriage noise?
Thank you for the tips. Nothing seems loose -- nothing moves when I pick up the printer, and nothing is getting in the way of the y carriage. The axes have some resistance when moved by hand but there are no rough parts -- they seem to move smoothly. I used superlube 21030 on the bearings during assembly (after soaking them in IPA and drying them), and I still have to clean small amounts of lube off the rods after prints, so I don't think that's the issue. I used the belt tension checker in the LCD and the y belt is right in the middle of the range (258 I think) (the X belt is a bit tighter but still slightly over 240). The belts and idlers seem straight visually, not sure how else to test them.
The only thing I don't fully understand from your post is the question about the bed mountings. Are you talking about the 9 bolts connecting the heatbed to the y carriage? If so I'm pretty sure I didn't overtighten them.
Beyond that, if this is just a resonance issue, it's not a huge deal -- it's not that loud. Just want to make sure whatever's causing that noise isn't going to damage the printer. Thanks again.
RE: Y carriage noise?
youch. I don't have great hearing, played it back a few time. What the heck is that "marbles in a frying pan with rocks" sound?
If I had to guess, i'd say your bed isn't seated.
RE: Y carriage noise?
What do you mean by that? How would I fix it?
RE: Y carriage noise?
I recognize the noise. It's a rattle. I had it on my bed after I changed the bearings out. You just did exactly the same thing sort of - put your new bearings in.
Take a hold of the right closest corner of the bed with the sheet on it. Move it up and down veritcally with your fingers - give it a solid pinch and tell me what happens when you move it up and down. Does it "click" and allow you to move it?
RE: Y carriage noise?
I'm mid-print now, (not using the noisy area), but I'll try that in a few hours. If it clicks as you describe, what would you suggest doing?
RE: Y carriage noise?
Do you remember when assembling the bed you put bearings on the rods, then mounted those bearings onto the bed and finally screwed the bed onto those little spacers? Something in that process is not tight enough and is allowing the bed to rattle when the Y axis does certain dance steps.
If you find the bed has some looseness (check each corner - you are looking for slight vertical motion - it should NOT move when you pinch it hard and move a corner up and down) you'll need to start reverse assembly. Take a look before you unscrew anything - try and see what is allowing vertical movement. you have to eliminate that.
RE: Y carriage noise?
@jordan-4
The only thing I don't fully understand from your post is the question about the bed mountings. Are you talking about the 9 bolts connecting the heatbed to the y carriage? If so I'm pretty sure I didn't overtighten them.
When connecting the Y carraige to the linear bearings it's possible to overtighten; if your printer has 'U' bolts it is particularly easy; Prusa changed the mountings a couple of months ago so the problem is becoming less common.
Cheerio,
RE: Y carriage noise?
Yes - the whole magilla. You can't think about it as a micro thing like 9 screws. You can warp the bed tightening those screws. The clips that hold the bearings that hold the rods to the bed are what I am thinking has a loose spot. The test is shaking the bed corners vertically . Let's see where you are when your active print stops
RE: Y carriage noise?
Thank you both for the suggestions. The bed doesn't move when I pinch the corners. I was very careful tightening those 9 screws; I tightened them in the order the manual recommended, and I tightened them evenly without using too much force. And my printer has the newer hardware for attaching the bearings to the carriage. As far as I can tell I'd have to disassemble a fair amount to try tightening or loosening those bolts, right? Do you think that's worth doing?
RE: Y carriage noise?
I was very careful tightening those 9 screws; I tightened them in the order the manual recommended, and I tightened them evenly without using too much force. And my printer has the newer hardware for attaching the bearings to the carriage. As far as I can tell I'd have to disassemble a fair amount to try tightening or loosening those bolts, right? Do you think that's worth doing?
It's one of the things I'd check.
Put it aside for the moment and do the resonance check; if that turns out to be it then, as long as you're confident, there may be no need to worry about the mounts.
Cheerio,
RE: Y carriage noise?
It is quite possible there is nothing amiss at all. Certain infills make a peculiar sound - for example, 60% hexagon infill makes a hell of a shaking. If your prints aren't suffering any ill conditions - move to dampening noise (squash ball feet for the win)
RE: Y carriage noise?
Ok, thank you both. I'll keep an eye out for print quality issues and an ear out for worsening noise. And I'll buy some squash balls 🙂
RE: Y carriage noise?
I remember those days = incremental improvements, understanding each noise. I recently did another round of print quality improvement attempts - and my X/Y movements are now nearly silent except with 60% or higher hexagon infill.