Degraded bearing

Please Login to Comment

Hi All
After a 42 hour print, I have noticed the bearing around the printer had been quite degraded. Does it affect the print in the future? If so, how can I fix it?

Could you post a photo please? And hats off to you for a 42 hour print :-)

I don't know if this is classified as a heavily degraded bearing and this is the x-axis bearing
I kind of wiped the damage of the right bearing but the left one is still left untouched

Yeah doesn't look good, but doesn't look fatal either ;-) Could it be that over such a long print any debris and dust has been ground down to that fine powder which then collected on the wheel? The clean wheel doesn't look too bad.

If the wheel itself is grinding then there could be a few problems, including the eccentric being too tight, or the bearing being faulty. I personally think they should all be sealed bearings and I've been meaning to replace mine for a while

Well the only modification I did to the x axis is the belt tensioner and that’s because my mum hit the metal plate on that end with a hammer and I do have to stretch the belt quite a bit. And idea of how to fix it?

Two thoughts come to mind. One is over tensioning. Too tight just just as bad as too loose in its own way. If you move the carriage by hand while you tension the belt, you'll feel that at some point it becomes hard to move and the vibrations are stronger. Go back a bit from there.

The second is alignment. The debris could be coming from the belt if it's rubbing on the extrusion. Perhaps something is bent that needs to be hit with a hammer the other way ;-)

Well I did try to hit the metal plate again but it did barely anything except damaging it even more. Is there any tensioner that is designed specifically for the cr-10s. I think when I said I have stretch the belt quite a bit I means when I’m installing the tensioner (when It should feel the same tension as not installing one) because I can’t really find one suitable for the cr-10s so I used a cr-10 belt tensioner which I feel is too short.

I just see I have the same problem. See my topic "CR-10S Heavy wear of the x-rollers".

This has nothing to do with belt tension.
The dirt doesn't come from the belt, the dirt is abrasion from the rollers.
The rollers must have an even wear on the whole surface. In the appendix you can see how this should look like.

I see that I am not the only one with this problem.
But I have more problems and will have to return the printer.

BTW, I have 7 years of experience in printing and designing printers.

Well I’m printing the makers muse lattice torture test now and i didn’t see any problem so far

So the bearings need to be replaced? Couldn't be much else.

Btw I have 5 solid months of experience with printers

In the simplest case the bearings, in the worst case the profile.
It is more likely that it is due to the profile. I can hardly imagine that different bearings were used.

What about the extrusion causes this? The wear looks so even.

I've had single bad bearings that grind and don't spin well in other things. I just assumed some random manufacturing defect.

This is quite normal if the extrusion has a wrong flank angle.

Sorry for asking so many questions... Is this a manufacturing error or does it happen in shipping? If imagine it all comes from the same shaped extruder. I might be getting some extrusions soon and I'd love to know what to look out for.

It is not certain whether all extrusions come from the same manufacturer.

I have worked a lot with extrusions, but the 45° angle was never important for the construction.

If you buy rolls and extrusions from the same manufacturer, they should fit together.

Cheers. So next question (if you don't mind). My eccentrics are not done up so tight that the wheels would wear like that I don't think. Does that just mean they're too loose? I've had so much trouble getting the gantry sorted that I look at the prusa setup with much envy!

The best thing is to press the wheels as little as possible and see if the print quality deteriorates.

If the x-wheels are too loose, then the nozzle will snake up and down and maybe you'll have waves of post swing on the y-sides.
If the Y-wheels are too loose, waves are created from oscillations on the x-sides.
If the z-wheels are too loose, the well-known z-wobbling occurs.

By the way, on the picture you can see how different the wear of the wheels is above and below. This is due to the inferior quality of the extrusions used.

Thanks for that. That pic illustrates it nicely. I think my wheels are about right from your description. So many factors :-)

Regarding z-wobbling by loose z-wheels, I've just made an unpleasant experience.

Because of problems with z-homing I relieved the inner wheels. While the inner wheels are still tight against the extrusions, the outer wheels are already loose. By the way, a sign that the x-ends are placed too far outside.
The vibrations of the motors now cause the frame to vibrate.

On the pictures you can see how this affects the print.

In addition, the printer now stands directly on a table while previously standing on the foam mat that came with the packaging.
Now I want to find out step by step whether it's just the loose wheels or whether the damping by the foam mat also has an influence.

I had a similar problem but thankfully it was easy enough to fix on mine. There was enough play in the screws holding the extrusion to the bracket that I could loosen them, tighten up the wheels, then do then back up. It did make a difference to the vibration for sure.

If this is possible in general, then this is the simplest solution for now.
Thank you!

A clean solution would be if all three wheels were equipped with excenter. Then all wheels could be adjusted exactly.
If the wheel system is not exactly right-angled, it happens that the x-unit is aligned obliquely.

Sorry for my off topic, but this is the only way I can write in a group.
I can not write a new topic anymore.
BTW, it worked only one time that I was able to create a new topic.

Does anybody know what's wrong?

What happens? It's the new topic button not there of does nothing happen when you click it?

No, no Topic button visible any more.

Did you work it out? Perhaps I could start the topic you were going to start...

Thanks for your offer. I will come back to that.
I have no more problems now, the printer will go back tomorrow ;-)

You're obviously authenticated or you couldn't post at all. Very strange.