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martik
01-12-2014, 02:40 AM
I have 9mm and 10mm bearings (5mm thick inc washers) that I need to fit to a 3/8" shaft on a cross feed lead screw. Would it be feasible to grind out the 9mm to 9.53mm (.020" larger) or will the 10mm perform adequately with the loose fit? I would prefer not to turn down the 3/8" shaft.

Thanks

LKeithR
01-12-2014, 02:59 AM
A bearing is a precision device; grinding it out will completely defeat the purpose because you'll never get it round. And putting a 3/8" shaft in a 10mm bearing is not a good idea either; you'll have almost .020" of slop between the two. You have two choices: Either get a bearing with a 3/8" ID or turn the shaft down to fit the 9mm bearing...

macona
01-12-2014, 03:38 AM
Yeah, a 10mm on a 3/8" shaft will be fine, it is just a little thrust bearing.

ikdor
01-12-2014, 03:38 AM
I'd be inclined to make a sleeve to increase the shaft diameter to 10mm.
Igor

martik
01-12-2014, 03:53 AM
Since the load is axial I figured the play in the 10mm wouldn't matter much. Making a .009" thick bushing would be a challenge.

darryl
01-12-2014, 04:21 AM
Of course a 3/8 ID ball bearing is only $2-

macona
01-12-2014, 04:22 AM
He is using a thrust bearing, not a radial bearing.

Peter.
01-12-2014, 04:23 AM
I used 10mm thrust bearings on my monarch cross-slide shaft which is 3/8". Can't detect any issues with it.

martik
01-12-2014, 04:28 AM
Closer to $25 shipped to Canada. Just made the brass sleeve, not too difficult.

RichR
01-12-2014, 11:56 AM
Hi martik

Making a .009" thick bushing would be a challenge.
You could bore out a piece of brass and press it onto the shaft, then turn that down to 10mm. If you only have one lathe, lock
down the gib for the cross slide and use the compound.

duckman
01-12-2014, 08:45 PM
One thing to remember with thrust bearings 1 race has a small bore and the other race has a larger OD, the small bore fits on what ever is rotating, generally the bigger OD fits into a recess that keeps the shaft aligned.

martik
01-12-2014, 08:56 PM
One thing to remember with thrust bearings 1 race has a small bore and the other race has a larger OD, the small bore fits on what ever is rotating, generally the bigger OD fits into a recess that keeps the shaft aligned.


From some photos in the catalog, the washers appear slightly larger than the bearing.