Linear Guide too tight

I know I should not buy linear guides from the far east - but I did it again.

Now I have a MGR15 linear guide which is much too tight (two ball rows in the block). Has anyone an idea what I can do? The ball diameters are 3.14 mm. I bought two guides and 4 blocks. One of the guides is ok, so the second one is too big. Is it possible to hone or grind the guide or widen the block?

Can you see the rows of balls? Is there a small gap between the balls or are they tightely packed? It might help to remove one ball/row.

There are two rows with big gap on each side. One row presses at the upper corner, the other in the middle. They work together unfortunately.

Maybe I try buying smaller balls. I double checked, they are 3.18 = 1/8 inch. I have a supplier, who offers 3.175 mm balls with good precision, G10.

Edited 1 time(s). Last edit at 07/18/2018 11:19AM by JoergS5.

Try doing a burn in, run the carriages over the guides for a while and they might end up running more smoothly after the first few hours.

Thank you for the idea. I thought about something similar: running the carriages with a lapping / honing paste. After the correct preload is reached, exchange the balls and clean all.

The guide is manufactured asymetrical: on one side it looks ok, on the other the form is different. I have nothing to loose...

P.S. I will not burn it with the carriage, as it will destroy it when using paste. I will build a construction for moving the balls over the guide to burn in.

Edited 1 time(s). Last edit at 08/02/2018 09:04AM by JoergS5.

By burn in I just meant put it to use, not with abrasive paste. Let any bumps/high spots wear in. That being said I doubt it would be a good idea if there is a defect to the point you can see it with the naked eye. Not sure if that's recoverable.

I will stop investigating now and take it the expense as experience... I bought some THK linear guides now and am very satisfied.

I will build some jigs for woodworking, there I have usage for stuck linear guides (e. g. for a cross table).

Thanks for your help!