Bearing size for IH Mill

I am going to be converting my IH Mill to CNC and was wondering if anyone has any information of the bearing dimensions or manufacturer and model number of the bearings used for the X,Y, Z Axis ballscrew mounts.

Rod

it really depends what size ballscrews your going to use. Look at the end machining for the ball screws selected and go from there.

I'm using 3/4" ball screw and the shaft will probably be 1/2" Dia.. I'm trying to get an idea for what people have already used in their builds, and have had good results with. I'm not very familiar with bearings and do not want to purchase the wrong bearing and have to repurchase them.

I have used 20mm ball screws on the X and Y with the drive end bearings being 15 x 32 x 9mm angular contact. 7002B Bearing Angular Contact 15x32x9 Ball Bearings ANGULAR_CONTACT
On the z axis my ball screw is 25mm and used 20 x 37 x 9mm on the drive end. It really depends how the mounts are made. Normally 2 angular contact bearings are used on the drive end. These are configured back to back with a spacer in between to allow for preloading the screw. If you have imperial sized ball screws just find some angular contact bearings to fit the end machining on the screws and then design your mounts accordingly.

Not too sure about using a spacer between the angular contact bearings.

There should be a counterbore on each side of the end plate. The bearing should press in on each side of the plate keeping the outer races apart so the inner races can be tightened or preloaded. Usually by 2 nuts or good locking nut.

Your correct, that's the way I did mine. Counter bore on each side on the mount with a 3/16" space between. Then use the nut to set the preload.
The other way I have seen it done is with a counter-bore to the depth of both bearings with a spacer between then have a cover to hold bearing within the counter-bore using the spacer to set the preload.