I completed my conversion of my X2 Mini Mill with the CNC Fusion Thompson ball screw kit and I haven't used it much until lately when
I had to make some small parts. Well I have about .008 backlash in the Y axis I want to put some bigger balls in the nut. I measured the original balls and they are 0.1248 on about the half that I measured. I found bigger balls but how do I know what size to get? I don't want to buy balls that are not big enough nor do I want to get balls that are too big. Where do I start? I sure could use some help if anyone has gone through this procedure.

Thanks for any and all help.

Jack

The new oversize balls arrived today from Florida and they went in the ball-screws without a great deal of effort. I practiced putting the balls back in while I was waiting for the new ones to get here. The mill is now back together, and after checking I now have about 0.001 backlash in both the X and the Y axis. I suggest that "It's good enough for the girls that I go with" and I am a happy camper. I will be making some more little parts tomorrow.

I know everybody said that I will wear out the screws early but my little mill sees very little running time and they will probably outlive me. Best $27.00 that I have spent in a long time.

J D

I just love it when things go right for a change.

On your advice I installed .1265 balls last weekend and it seems to work great. Mill is still being converted so no test other than feel but it is a huge improvement. I have only done one so far but the factory feel was disappointing (lots of slop) With .1265 balls it feels much better. Strange, I removed 68 balls and 69 larger balls fit nice.