View Full Version : Cheap Chinese bearings SBR25UU how to fix them if not seated correctly.

04-06-2017, 09:24 AM
Hi I bought 8 cheap ass chinese bearings from ebay and they all slide beautifully but 4 of them were fitted off centre so when on the rail we get this (I already fixed one of them that's why only 3 are bent).

We ID'd the problem
the plastic bearing houses are not fitted straight inside the aluminium housing.

so I took an aluminum strip 5mm thick and the put the bearing in the vice open side down using the strip to protect the outside shell and tightened. Which pushed the internal ring in a straight position it was incredibly easy.

I will update will pics in a few hours of how I did it and the difference, I managed to get 7 straight bearings out of the 8 I bought but I will have another go today with the 8th As I went a bit far yesterday with tightening the vice and and I need to push it back the other way.

I also decided to test how much weight the 15mm hiwin rails can take so I stood on the carriages and almost fell on my ass lol. After standing on 4 I tried standing on 2 and one of them shot off and I ended up standing on a single carriage ;) it was still super smooth to an almost lethal level.

04-06-2017, 03:00 PM
21835 Precision engineering lol

After I straightened them