Prusa i3 MK2S Clone Bearings


Hi has anyone looked into what are the best bearings to use for quality on a Prusa i3 MK2S Clone, I brought the Chinese LM8UU bearings off Alliexpress and they have a lot of side ways slope and bite in causing vibrations.


Misumi is generally considered the gold standard in LM8UU bearings but they’re hard to find and expensive. Igus Drylin bushings are whisper quiet, but they’re not well-suited to holding much weight so they shouldn’t be used on the X carriage. I use Igus bushings on Y and for X and Z just buy a bunch of Chinese LM8UUs and pick the best of the bunch, in my experience 2/3 of the batches are pretty solid and 1/3 are crap. It’s still way less expensive than getting Misumis, and I have no idea where to even find them in the US.

Also make sure you’re lining up the balls in the bearings and that you have them sitting on the bottom wherever they are holding weight (X and Y).


To lube, or not to lube. That is the question.


Use a 3-in-1 oil, mine says sae20, this will keep working the grit out.

When I get new bearings, I clean them in some mineral spirits, and work them thru with a small bamboo skewer, then dry them.
Then I add some 3in1 oil and work then thru again, and dry again(just removes the excess). Then I work them on a spare rod I have, and find the ones that are still sticking and repeat the process with these.

But I now know why everyone went with roller bearings on a aluminum frame, its much easier to get good bearings. But the design I like (smartrapmini) uses rods, so I have to cope.

PLA printed bushings can work if you can reduce or eliminate the sticktion, lemon pledge furniture polish works.