How would YOU go about this job.

If it were retrofitted with a thrust bearing it would be easy to change out years down the line if needed.
 
If you were to substitute only a thrust bearing, what would keep the axis of rotation centered?
 
My concern with your method is a ballnose endmill might not leave a smooth enough surface at the bottom of the radius, exactly where the rolling elements are going to be contacting the races. Do you have a way to grind the proper radius after you mill it larger so that the race surface is smooth enough for long operation? Even with low speed operations, surface imperfections are going to cause stress risers and metal to metal contact that will cause a premature failure.

What material is this made from? Standard bearings are made from 52100 and are very hard. They can be hard turned, but it takes the right tooling and a very rigid machine. Some bearings are case hardened, so you can machine below the case hardened layer, but then you will need to reharden to get any useful life out of it.

Many large bearings are reconditioned by grinding away the pitting and fitting new rolling elements to compensate for the change in dimensions, so your idea for this repair is used, but it is done by grinding and not machining, so depending on the material, that is likely your best option.

As far as the cage, there are full complement bearing designs that don’t use a cage, you will need to size the rolling elements properly so that there is not too much play that will let them bunch up to one side.

The idea of machining it flat and putting in a stock axial thrust bearing sounds like the best way to do it.
 
OTmachine said:
If you were to substitute only a thrust bearing, what would keep the axis of rotation centered?
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Same way it currently is held centered. One part has a round boss the other goes over. The bearing would sit right were the current bearing is cut in.
 
@Ischgl99 to answer your questions,the material is cast iron and no I can not grind it after milling,BUT like I said before this is a windmill and not a high presicion tool and the cast iron is not hardened in the first place. That being said,the client are happy with it just being milled with the ballnose cutter and do not want to go with the thrust bearing option because of the expense. The bearing is a bit pricey. But I gave the options and he is happy. I gave the pros and cons and he still said I must just mill it and I did not want to **** him off so I will do what he wants.

Thank you for your input, I do see your point of view.
 
Suzuki4evr said:
@Ischgl99 to answer your questions,the material is cast iron and no I can not grind it after milling,BUT like I said before this is a windmill and not a high presicion tool and the cast iron is not hardened in the first place. That being said,the client are happy with it just being milled with the ballnose cutter and do not want to go with the thrust bearing option because of the expense. The bearing is a bit pricey. But I gave the options and he is happy. I gave the pros and cons and he still said I must just mill it and I did not want to **** him off so I will do what he wants.

Thank you for your input, I do see your point of view.
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Will you mill the grooves say 4mm deep to leave a 4mm gap for a 3mm drilled ring to keep the balls separate?
 
Suzuki4evr said:
Quick question. Would HDPE do,because I have some on hand?
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For what? The ball cage? Polyamide would be better since there are commercial bearings with polyamide cages, but if all you have is HDPE, it should work provided the bearings are not highly loaded.

Suzuki4evr said:
@Ischgl99 to answer your questions,the material is cast iron and no I can not grind it after milling,BUT like I said before this is a windmill and not a high presicion tool and the cast iron is not hardened in the first place. That being said,the client are happy with it just being milled with the ballnose cutter and do not want to go with the thrust bearing option because of the expense. The bearing is a bit pricey. But I gave the options and he is happy. I gave the pros and cons and he still said I must just mill it and I did not want to **** him off so I will do what he wants.

Thank you for your input, I do see your point of view.
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I understand completely, customers always want the cheapest repair, and rarely understand the ramifications of their decisions. I thought it might be cast iron from the pictures, in that case, it should machine well, but you might want to touch it up with a fine sandpaper a bit by hand to take any high spots off. Bearings are under a lot higher stress than most people realize and the smoother the surface, the better the life will be.
 
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