Bearing shims and preload

available the

press items

comes to worse,

If you are pressing in one direction only I wonder why you don't set the bearings in a tandem configuration. I would not worry about preload since you are pressing is one direction. You just have to have the inner and outter retainers exactly the same width and that will give you 0 clearance. Preload is necessary only if you have to eliminate all end slop on the shaft but pressing in only one direction it should not be necessary for any added preload.

In short go for the no play and if you want you can compute the shim you need to get the preload that is given for that bearing combination. There should be a table somewhere for preload vs. shim thickness. I would leave out the shim.

John

I still have to deal with the weight of the press so I can't go tandem. The other end has a deep groove bearing for radial support.

When I look at bore diameters, I think they mean the ID rather than the OD. For a 7206 it looks like +4 to -16 micrometers which is something like .00015" to -.0006" I don't have shims that fine. I'll have set the bearings up on a granite and determine with a test indicator what amount of preload may be ground in already tomorrow.

I'm probably putting too much thought into this, it isn't a high speed spindle or a high accuracy lathe, just a ball screw operated press that resolves to +/- 0.001".

I've been putting in high buck bearings when they crash it, I'm ready to try 62 dollar a piece unmatched ones in pairs instead of the 350 dollar sets.

Wes

available the

to press items

comes to worse,

I'm going to

Mark Rand RTFM

Yeah, I figured it out after I found the right table. I've googled all over for bearing shims but came up empty. I know they exist, I've pulled down housings that had some that were extremely thin.

Of course my interest in setting preload properly has other future projects in mind where it might really matter.

Wes