Starrett ruler question

[dennis thompson]

I just bought a 12" Starrett ruler on Ebay. When I compare it to my other 12" rulers it's 3/16" longer. On the ruler it says "shrink 3/16 to foot".
Does anyone have any idea what that's all about?
Thanks
Dennis

[Ray Newman]

I do believe that it is a pattern maker's rule.

The rule takes into account the metal shrinkage when making wooden patterns for castings.

[Frank Drew]

It's called a shrink rule, and there are various sizes; Ray explains the reason. A bit more on them:

http://www.nonesuchtools.com/pmkr/shrink.html

They also make exact size rules; great company, Starrett.

[glenn bradley]

I'm thinking that Dennis was not after a shrink-rule. Darn.

[Bruce Page]

I'm thinking that Dennis was not after a shrink-rule. Darn.
Yep. I was burnt by one of those things once.
Not much use for them unless you're a pattern maker.

[Peter Quinn]

That must be why most of my cuts come out inaccurate in some way. I have been using a shrink rule all this time! Or maybe a dufuss rule?

[dennis thompson]

I certainly wasn't after a "shrink" ruler, but it was only $5 so it's a pretty cheap lesson
Dennis