Can someone surface grind something for me? 4140 PH

Cadillac STS

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I am going to make a base for my QCTP and take out the compound until needed. Looking for more rigidity.

I have a piece of 4140 PH that is about 2X2X6. I just need it surface ground on 2 opposing sides so it sits straight on the lathe cross. It can end up less that 2 inches as I will adjust the tool heights as needed.

Can anyone do this for me and what price? Please PM me through this site. Anyone in West Michigan so I can drop it off. Mail is good too.
287244
 
You may not want it ground. I made one from a chunk of cast iron and ground the top. Looks pretty but the hardened tool post likes to turn on it. A little roughness may help.

Greg
 
Do you have a mill? You are just fine if you lap the top for measurement purposes. I agree with f350 about the bottom. Looks like a great project! -- What lathe are you mounting this on?
 
I thought the ground surface would be better for holding the tool post and keep it from moving

It is a Wabeco D6000e German made precision lathe.
 
More friction milled than ground . I should say a better grip .
 
Might not be a bad idea to relieve the bottom..??
 
I've never tried relieving the bottom. For minimum chatter you'd think that having as much metal-to-metal contact as possible is the way to eliminate minute movements due to flex in available gaps.

My 4-way and both my QCTP have never slipped. Both of them are 'smooth', by which I mean they are coarse ground so grinding marks are seen. I'd be just as happy with a face milled bottom.
 
Looks like you have a pair of T-slots to mount your block to.
 
Looks like you have a pair of T-slots to mount your block to.

Yes two T slots. I am going to just try two holes to T nuts. Might mill two mating tracks on the bottom of the base but I don’t think that will be needed. The compound does not have mating tracks.
 
Consider milling 2 long T nuts and using 4 cap head screws to hold it down. Ground or not, it won't move at all. No need for mating keyways, and a lot of work (and precision) that will probably be unnecessary.

(Unless you'd like the challenge - then I bow to you!) ;)
 
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