S3 making noises while printing

[Eepa 0]

One of our S3 printers started making noises last spring and we saw that the Y-rod had some bad grooves in it so we decided to put on new Y-rod and bearing. I just did that today (school moves slooowly during summer) and it's still making noises. Now Y is much quieter but X is making a racket. All other rods seems to be okay and I can't see any grooves so nothing is obviously wrong. Any ideas what I should try next?

 

Here's a short video of the noise the machine makes.

 

[IRobertI 521]

It's always a little bit difficult to tell on a recording but I'm suspecting belts even though the noise is a bit more "sharp" then what I would normally associate with a  tired belt. But it could well be the recording skewing the sound a bit as well.

 

Often it's the short belt that is the most noisy so one quick thing you could test is to loosen the screws that holds the motor in place and lift it up (to try to disengage the belt from the pulley) and then move the print head manually and see if the noise goes away/reduces. You might have to remove the motor completely if the belt is stubborn and still rides too much on the pulley to test properly.

 

The long belts can also be a bit cranky but not as easy to test for.

[Eepa 0]

I took the whole printinghead assembly off and I get the same noise by just moving the x and y belts so it's definitely them. I'm not even going to touch the z axis until I get these sorted, if I can. I have enough problems already. =D

 

I'll first try to loosen each belt separately and see if I can isolate the noise maker or if it's everything...

[IRobertI 521]

Honestly I would just swap them all if it is one/several of the belts. They are quite cheap and the way they are mounted means you have to take out at least a couple of rods and also the motor(s). At that point you might as well do it all. It'll probably take you 1-2 hours the first time you do it and you take your time.

 

Before you do it you'll need to print out the alignment sticks for squaring up the print head rods after the replacement. Reach out to your reseller, they should be able to get you a guide for the repair as well as STLs for the rods (or you could pay them to do the replacement for you).

[Eepa 0]

I did some deassembly and the noise only went away after I took out both long x axis belts. Taking out the short x axis motor belt didn't seem to make any difference.

 

The machines is about 3 years old and it's in heavy use in a university but the belts don't seem to be worn down and there was minimal rubber particles in the corners, so it's somewhat odd why it suddenly started making noises.

 

The printer is already in pieces but we have several others so printing the alignment sticks won't be a problem. Can't find a belt replacement kit anywhere easily but the teacher probably can get them from the place we bought the machines.

[IRobertI 521]

I don't know the exact physics behind the noise, I've always assumed that the belts dry out and it's friction against the pulleys, but that's just a guess. But the squeaky noise is very common, it's been around since the UM2 launched and I've done quite a few belt replacements over the years.

 

The parts you need are these:

2x 225586
2x 225739
2x 1758