"Ben Jackson" wrote in message
...
Ok, this is a stupid question, but are the inside faces of a machinists
square supposed to be square, or only the outside faces? Or, put another
way, are the blade and base faces both parallel?

I've got the old "never take two clocks to sea" problem -- I've got two
squares and I piggyback them and I can see light between the blades.
So now I don't know which one is off...

--
Ben Jackson

http://www.ben.com/

There's a good article in the most recent HSM on indicators that briefly
describes how to check a square with a simple fixture and a good indicator.