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Mueller
10-26-2002, 09:05 PM
I have an application that requires a 1.5ID needle bearing to ride on a shaft, the shaft diameter is 1.40 OD. I'd like to make an inner race for the bearing. The OD of the inner race needs to be ground and hardened.

I've never seen the equipment for centerless grounding, can this be replcated in the home shop??

Of the OTS inner races I can purchase, the width is too small and the inner diameter is too small as well.

Rustybolt
10-26-2002, 11:20 PM
Nice to meet another Mueller. Centerless grinding is designed to do a lot of pieces real fast with consistant accuracy. I'm talkin tens of thousands of pieces with plus or minus .0002 Check out local grinding outfits and see if they can't grind it between centers.

Mueller
10-28-2002, 12:53 PM
Likewise....

I'm waiting for a quote from a shop, I hope to be sitting down when it arrives http://bbs.homeshopmachinist.net//smile.gif

WJHartson
10-30-2002, 08:45 PM
Mueller,

Have you thought about machining the inner race to size in length and ID with an oversize OD. Harden the race and shrink it on the shaft. Once that is complete grind the OD to the size you need. With a .050" wall thickness I don't know of a better solution.

C. Tate
11-03-2002, 09:49 PM
You can turn up to 60 RC if you want to make it on the lathe. It takes Cubic boron nitride inserts but is not very difficult and the finish can rival that of grinding.

Peter S
11-04-2002, 06:20 PM
I would put more effort into buying an off the shelf needle bearing and inner race and re-design your application to suit a standard unit. There is a large range of inners available. I am guessing it will be easier to remachine your shaft or housing than to make an inner race. Have you tried INA for bearings?

docsteve66
11-04-2002, 11:34 PM
i second peter's suggestion. Unless its near impossible, go with off the shelf bearings. There is good reason that bearings are so standardized. EXcepting sleeves and bushings, you tend to forget how you made the one of a kind thing and wind up re-inventing what you invented before. most times you a much bettter buying what you can. gives more time for real creativity.
Just one mans opinion.
Steve

Thrud
11-05-2002, 03:17 AM
Third Peter's suggestion. Torrington also has some pretty screwy bearings for your amusement.

C. Tate
Hey, long time - no lunch. How was the show? I really wanted to see the new Haas lasers.

I had to hang around for tests, but I have had considerable improvement from my lovely stay in critical care in 1999. So I guess it was worth missing even if it did frost my hiney something terrible! http://bbs.homeshopmachinist.net//biggrin.gif