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Granite surface plate, $500, Oakville, ON

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no it is recessed int the table.

244X36 is pretty small for a used surface plate at that price.

You are better off with this:


or similar. My experience with offshore plates is that they are perfect for home shop. Not professional A or AA quality, but solidly within B specs. I've looked at 4 in the 18X24 and 2 in the 24X36 range.

My used 18 X 24 Mitutoyo AA plate was 50$. It is worn, and is approx B grade now.
 
Can't really tell but betting it isn't 3 point mounted either. Takes it right off of my interested list.
 
Heres a stupid question.
Could a person get a piece of granite from a counter top place?
Would it have any kind of accuracy?
 
Heres a stupid question.
Could a person get a piece of granite from a counter top place?
Would it have any kind of accuracy?

No such thing as stupid questions.

Granite plates are a metrology platform. They are the basis of virtually all precision measurements. From the perspective of usefulness in metrology, a granite countertop is just about useless.

Here is another perspective. Even a grade A granite surface plate is useless unless it is mounted on the 3 design points on which it was sitting when it was originally lapped. Yes, even granite bends.
 
Heres a stupid question.
Could a person get a piece of granite from a counter top place?
Would it have any kind of accuracy?
agreed about mo stupid questions.

A friend of mine with a 15K$ mill and a 40K$ lathe refused to buy a surface plate. He tried counter top leavings (where a sink was cut out) and found surface variances up to .006 in height.

I guess someone could map it and lap it, but a BB surface plate is about 59$ on sale, and is fine for hobby work. Both of mine were within .001 overall with local variances at half that. It isn't worth the time to try to fix a flimsy 1" piece of granite.
 
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