Need Help!- Thrust Bearing install question

[mhackney]

I am about ready to drill and bore the holes for my Y axis thrust bearings. These are the 3 piece - 2 steel "washers" with a nylon disk holding the ball bearings - type of thrust bearing that I've seen on a number of mills here. Mine are 24mm OD, 12mmID and 6.35mm wide.

To what dimension should the hole for the 24mm ring be? Should it be slightly oversized so the outer ring can rotate freely? And how deep should the hole be? I suppose if the bore is slightly oversize, the bore should be deep enough to prevent the outer ring from pressing against the table bed.

thanks in advance,
Michael

[hoss2006]

Hey Michael,
If one of the steel rings has a larger OD, that one should be fit snugly in the bore of the spacer.
That would allow the other smaller one to spin freely with the leadscrew.
If both are the same OD either only make the bore deep enough for the inner ring
and let the other stand proud to spin freely or
if you want them flush with the spacer, make a 2 step bore with the inner bore just big enough to snugly hold the ring for location purposes (24mm) and the outer bore (25mm or so) to spin freely.
Hoss

[mhackney]

Hey thanks Hoss. My rings are both the same OD and I do need them slightly recessed, so I'll do a 2 step bore.

Cheers,
Michael