Suggestions for Boring .0015 over?

[3 Phase Lightbulb]

My bearings for holding my differential in my buggy arrived.. I ordered the bearings with a bore of 1.625 and they are exactly 1.625... I thought my differential bearing seats were also 1.625 but they are in fact 1.628 so I need to either take off .003 on my differential, or bore out the 1.625 bearings to 1.628..

Normally I would just use an edge finder and bore them out on my Bridgeport, but since I only need to take .003 off, I was wondering f there is an easier way? Could I just heat up the bearings with low heat and expect them to expand from 1.625 to > 1.628?

Here is a picture of them:



-Adrian

[tattoomike68]

boring a bearing it not that simple, they should be stone hard.

you can do it in a lathe with ceramics, turn it @ 2000 rpm. it will look like the 4th of july.

I would turn the diff.

[michaeljt]

The bearings a hardend, and would need to be jig bored. Can't you return them and get the correct ones.

[3 Phase Lightbulb]

I definitely don't want to turn it since I'm taking off so little.. I could probably just wrap some emry cloth/sandpaper around the diff's bearing seat and get it to fit since all I need to remove is .0015.. I'm just not sure how long that will take.

-Adrian

[3 Phase Lightbulb]

<font face="Verdana, Arial" size="2">Originally posted by michaeljt:
The bearings a hardend, and would need to be jig bored. Can't you return them and get the correct ones. </font>

The bearings are 1.625" and that's what I thought I needed.. The differential needs 1.628" . I quickly measured the diff before buying the bearings and It looked like 1.625.. The next larger size bearings jump 1/16" so I'll just turn down my diff..

I was going to turn a sandpaper flapper inside the bearing bore and see if I could clear another .0015 but I'll go try hand sanding down the diff carrier instead..

-Adrian

[Evan]

Chuck up the diff in the lathe and use a fine mill file. Run it in reverse and hold the tang/handle in your right hand at the back of the work, left holding the front of the file. This way it can't catch and bite you. Take off a bit and hit it with some emery. Blacken it with a sharpie so you can see what is coming off. Sneak up on it, it's easy to overdo. Use a file with a blind edge toward the shoulder.

[This message has been edited by Evan (edited 08-27-2005).]

[hoffman]

Maybe you could hone it. Just an idea...

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Deep Sea Tool Salvage

[Evan]

Hone the bearing IDs? I wouldn't touch them. It's liable to turn out badly.

[zl1byz]

Sounds like a job for a small tool post grinder on the lathe.

Mount the bearing in the chuck get it running true and take a bit out of the bore with a stone that will fit through the bore.

Take the bearing out of the housing and remove the grub screws (don't loose the grub screws) and chuck up on the extended inner race.

John.

[Forrest Addy]

0.003" is way too much shrink. You may not crack the inner race but you're sure to take up all the internal clearance and then some vastly shortening the bearing life.

Don't modify the bearings; you might have to replace them. Modify the diff. Chuck the diff up in the lathe and dial in the bearing fits. 0.002 isn't too much to machine/ file/polish off. Do a careful job and mike in a dozen places as you go and you can work down the the bearing fit to allow 0.0008" shrink per inch of diameter.

Heat the bearing up to 300 degrees and drop it on the fit.