Replacement bearings recommendation  

Re: Replacement bearings recommendation

I used the Misumi bearings in my initial build based on the reports of rattling, defective and unsmooth bearings I encountered in my research. So I don't personaly have any basis to compare them to the stock bearings. But I am very happy with the Misumi. From time to time there is a resonance that will get a rattle out of them. But it is extremetly rare and very brief.

They slide with much less resistence than the stock bearings because they to not have a seal. The stock bearings have a platic seal that causes friction on the rods and they do not move freely. For instance, gravity is not enough to pull a smoth rolling(non defective) stock bearings off the rod with the rod held vertically. But the Misumi bearings slide off with seemingly no resistence. I speculate that this decreased ressitence may allow for higher travel speeds before the steppers miss a step.

I would have also upgraded the rods at the same time but there was a 4 day lead time and I didn't want to delay my build. I don't have any reason to complain about stock rods. But I still may eventually try the Misumi rods in the interest of experimentation.

Re: Replacement bearings recommendation

Click the P/N for the OEM site, click the price to go somewhere and spend too much on them.

1. SKF LBBR8-2LS/HV6 : 19.52USD

2. KH08-PP : 15.77USD

3. VXB LM8UU : 10.37USD

4. igus drylin RJ4JP-01-08 : 1.99

I prefer the SKF ones myself. IMHO they are some of the best available.

Re: Replacement bearings recommendation

I would have also upgraded the rods at the same time but there was a 4 day lead time and I didn't want to delay my build. I don't have any reason to complain about stock rods. But I still may eventually try the Misumi rods in the interest of experimentation.

So for the Misumi rods: https://us.misumi-ec.com/vona2/detail/110302634310/?Inch=0&CategorySpec=00000042688%3A%3Aa%0900000028941%3A%3A8%0900000042718%3A%3Aa%0900000042685%3A%3Aa

What options would be optimal:
Material: bearing steel or 440C stainless steel
Heat Treated: Induction Hardened (or not hardened)
Surface finish: None, hard chrome, low temp black chrome
Shaft Fits Tolerance: g6 or h5
Type: PSFJ or PSFU

I can't believe how choices there are!

Re: Replacement bearings recommendation

Click the P/N for the OEM site, click the price to go somewhere and spend too much on them.

1. SKF LBBR8-2LS/HV6 : 19.52USD

I prefer the SKF ones myself. IMHO they are some of the best available.

Interesting, I wonder how much better the $20 skf ones are compared to the $5 Misumi ones. For x/y that's $120 vs. $30.

Re: Replacement bearings recommendation

Click the P/N for the OEM site, click the price to go somewhere and spend too much on them.

1. SKF LBBR8-2LS/HV6 : 19.52USD

I prefer the SKF ones myself. IMHO they are some of the best available.

Interesting, I wonder how much better the $20 skf ones are compared to the $5 Misumi ones. For x/y that's $120 vs. $30.

I'm not sure myself, but I am willing to bet the jump from the standard chinese LM8UU bearings to the $5 Misumi bearings are a huge jump, while going from $5 to $20 is a much smaller jump. For me it was just a matter of not wanting to worry about it any more, and I was (perhaps some would say foolishly) willing to throw money at the problem and make it go away.

Re: Replacement bearings recommendation

What options would be optimal:
Material: bearing steel or 440C stainless steel
Heat Treated: Induction Hardened (or not hardened)
Surface finish: None, hard chrome, low temp black chrome
Shaft Fits Tolerance: g6 or h5
Type: PSFJ or PSFU

I can't believe how choices there are!

Definitely G6, bearing steel with induction hardening. I am undecided on the hard chrome. It does make it a harder surface then hardened steel alone. But I understand it is already plenty hard as standard. So it may be more about aesthetics. Unless I can find a reason not to I would go with hard chrome because I tend to over do things.

Re: Replacement bearings recommendation

I'm not sure myself, but I am willing to bet the jump from the standard chinese LM8UU bearings to the $5 Misumi bearings are a huge jump, while going from $5 to $20 is a much smaller jump. For me it was just a matter of not wanting to worry about it any more, and I was (perhaps some would say foolishly) willing to throw money at the problem and make it go away.

How many rows of balls do the SKF bearings have? The picture shows what looks like 8 but that may just be a stock picture.

Re: Replacement bearings recommendation

I'm not sure myself, but I am willing to bet the jump from the standard chinese LM8UU bearings to the $5 Misumi bearings are a huge jump, while going from $5 to $20 is a much smaller jump. For me it was just a matter of not wanting to worry about it any more, and I was (perhaps some would say foolishly) willing to throw money at the problem and make it go away.

How many rows of balls do the SKF bearings have? The picture shows what looks like 8 but that may just be a stock picture.

They definitely have 8 glorious rows. The application note document from SKF for it's bearings refer to it as a "precision instrument" and they certainly feel that way.

Re: Replacement bearings recommendation

Definitely G6, bearing steel with induction hardening. I am undecided on the hard chrome. It does make it a harder surface then hardened steel alone. But I understand it is already plenty hard as standard. So it may be more about aesthetics. Unless I can find a reason not to I would go with hard chrome because I tend to over do things.

Here is a ton of info on rods from Misumi, I may try the LTBC coating:
https://ultimaker.com/en/community/5103-ultimaker-black-edition?page=3

Re: Replacement bearings recommendation

Definitely G6, bearing steel with induction hardening. I am undecided on the hard chrome. It does make it a harder surface then hardened steel alone. But I understand it is already plenty hard as standard. So it may be more about aesthetics. Unless I can find a reason not to I would go with hard chrome because I tend to over do things.

Here is a ton of info on rods from Misumi, I may try the LTBC coating:
https://ultimaker.com/en/community/5103-ultimaker-black-edition?page=3

Well I like to over do things but not to the point of black chrome! Everyone has a limit i guess.

Re: Replacement bearings recommendation

Definitely G6, bearing steel with induction hardening. I am undecided on the hard chrome. It does make it a harder surface then hardened steel alone. But I understand it is already plenty hard as standard. So it may be more about aesthetics. Unless I can find a reason not to I would go with hard chrome because I tend to over do things.

Here is a ton of info on rods from Misumi, I may try the LTBC coating:
https://ultimaker.com/en/community/5103-ultimaker-black-edition?page=3

Well I like to over do things but not to the point of black chrome! Everyone has a limit i guess.
True, especially since it's cosmetic only.

Re: Replacement bearings recommendation

Has anyone bought the Misumi bearings? I am considering changing out all 10 bearings and I just wanted to know if it was worth the $50 expense.

I am also considering changing out the rods as well, but I am nervous about getting the lengths messed up or having to cut it, which I really don't want to do.

In terms of upgrades how much of a benefit do you guys think upgrading just the bearings would be vs upgrading the bearings and rods?

I don't mind the estimated cost, but I am not sure if its worth the risk of changing out all the rods and getting the lengths slightly screwed up or if you are going to buy nice new bearings but using it on the original rods wouldn't make sense.

Thanks,

~Kaizers

Re: Replacement bearings recommendation

In terms of upgrades how much of a benefit do you guys think upgrading just the bearings would be vs upgrading the bearings and rods?

What problem are you trying to solve? That will feed into the answer for you.

My Y-axis bearings were noisy, so I replaced those. Print quality was fine before and now after my bearings swap.

John

Re: Replacement bearings recommendation

Worth a mention to ensure the orientation of the bearings is correct. It mentions it in the manual that they should all follow the same pattern it you reverse them it could be the cause of the noise people are getting. My Y carriage can be slightly noisy but nothing to make me want to replace the bearings.

Reference Image:

https://d17kynu4zpq5hy.cloudfront.net/igi/prusa3d/RnqacYNhS1NQNpHl

Re: Replacement bearings recommendation

Worth a mention to ensure the orientation of the bearings is correct. It mentions it in the manual that they should all follow the same pattern it you reverse them it could be the cause of the noise people are getting. My Y carriage can be slightly noisy but nothing to make me want to replace the bearings.

Reference Image:

https://d17kynu4zpq5hy.cloudfront.net/igi/prusa3d/RnqacYNhS1NQNpHl
Interesting, I wonder why this isn't specified for the x and z axis?

Re: Replacement bearings recommendation

Worth a mention to ensure the orientation of the bearings is correct. It mentions it in the manual that they should all follow the same pattern it you reverse them it could be the cause of the noise people are getting. My Y carriage can be slightly noisy but nothing to make me want to replace the bearings.

Reference Image:

https://d17kynu4zpq5hy.cloudfront.net/igi/prusa3d/RnqacYNhS1NQNpHl

When I assembled my MK2, I understood that image to tell me to ensure there was a line of balls directly above the Y-carriage. Was there something more implied? I did not see anything suggesting a particular direction the bearing should be installed. Did I miss something?

Re: Replacement bearings recommendation

In terms of upgrades how much of a benefit do you guys think upgrading just the bearings would be vs upgrading the bearings and rods?

What problem are you trying to solve? That will feed into the answer for you.

My Y-axis bearings were noisy, so I replaced those. Print quality was fine before and now after my bearings swap.

John

Hi John,

I am actually not trying to solve any problems. My bearings doesn't make any noise and my prints are coming out perfect. The only reason why I was considering upgrading the bearings is because when I first installed the bearings in my MK2, one of the bearings had several of the little steel balls come out. So I know at least one of the bearings isn't 100% operational.

If at least 1 bearing had its internal balls come out so easily, I am worried that it might happen to other bearings.

Also for what its worth, Misumi just gave me 30% off on all its eligible products for 30 days, since I signed up a new customer account. Now the $50 cost is reduced to $35 for all 10 bearings. That makes it very compelling to me even if I am not having any current problems.

I just want to make sure that my MK2 runs perfectly, especially since I just ordered the multi-color upgrade lol.

Thanks,

~Kaizers

Re: Replacement bearings recommendation

Also for what its worth, Misumi just gave me 30% off on all its eligible products for 30 days, since I signed up a new customer account. Now the $50 cost is reduced to $35 for all 10 bearings. That makes it very compelling to me even if I am not having any current problems.

Indeed!

Re: Replacement bearings recommendation

Well, thanks to the 30% Misumi discount I decided to order the rods and bearings. I look forward to seeing what kind of difference it makes.