On Sun, 16 May 2010 06:04:18 -0700 (PDT), robgraham wrote:

Do I heat it to assist removal or deep-freeze it ?

Google is your friend:

"coefficient of expansion metal*"

First hit:

http://en.wikipedia.org/wiki/Coeffic...rmal_expansion

I'll leave the drawing of the answer as a excercise for the OP.

--
Cheers
Dave.