[mactec54]

[QUOTE=Jason M;
In my experience the photo of the double row angular contact ball bearing in mactec54's post is meant for applications requiring less precision like electric motors, centrifugal pumps, things of this nature, and are found most commonly with an internal clearance that is looser than you would want for a ball screw application.


I don't think you will find these bearings in electric motors, & very few centrifugal pumps have them as well


If you have (1) of this type of bearing on each end of the Ballscrew, they will do a great job & just as good as, 2 expensive precision Bearings on (1) end Which you have to seal

Good brand name Bearings like this have around .0002 clearance, Like SKF Etc, so with (2) one on each end, you can put the Ballscrew in tension/light preload, to take up any clearance, so you get the best of both worlds, Great support & low cost

KKayler wants budget, this is the best for him & very little to do for set up

[arvidj]

...

If you have (1) of this type of bearing on each end of the Ballscrew, they will do a great job & just as good as, 2 expensive precision Bearings on (1) end Which you have to seal

Good brand name Bearings like this have around .0002 clearance, Like SKF Etc, so with (2) one on each end, you can put the Ballscrew in tension/light preload, to take up any clearance, so you get the best of both worlds, Great support & low cost.

...

I have been following this very interesting thread and admit that I do not have anywhere near the experience or expertise of those participating. However, I do have a question related to the "so with (2) one on each end".

There seem to be recommendations that the ballscrew support be fixed at one end and floating at the other to address thermal expansion issues. "so with (2) one on each end" makes perfect sense to address what ever small amount of clearance the bearings might have but also seems to go against the "one end fixed, one end floating" recommendation.

As a neophyte I guess I need some help getting my head around this.

Thanks,
Arvid