Thread: Valve Shims
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Old 06-25-2012, 08:03 AM
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WMarshy WMarshy is offline
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Originally Posted by CaptonZap View Post
The way I see it, the surface that rides against the cam lobe is harder than the lobe itself, and when you make a jillion of something, you design it so that you only have to manipulate it once for each operation, i.e. hardening.
So you punch it out, harden it through and through, temper it to design hardness, grind the od on a centerless gringer, grind the two faces at once, mark it and ship it.
My tenth mike cannot see any crown, so, the back is as hard as the front, and the surface gringer doesn't care how hard it is, and done correctly, the temperature never comes close to a tempering temp, and the bottom side rides against the bucket, so the surface finish is immaterial, the original wearing surface is not changed, and the hardness is not changed, and research and development is fun.
I just need a bunch of cheap chims.
Thanks for the input though. If you can find a fault in my reasoning, I'm listening. CZ
One can only guess exactly how they made them or heat treated them...I think its a mute point but agree with what you described would probably make the most production sense... I still think it would be nice to grinding one in half and check the hardness and compare it to the unground surface... If I had a spare shim and the tools I would do it but wouldnt let it stop me from just doing it if I didnt... I dont see a problem as long as the ground surface is put into the bucket...
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Last edited by WMarshy; 06-25-2012 at 08:06 AM.
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