Ah HaH, now I understand! That's why those Rolls Royces cost so much!
Steve
"Robin S." wrote in message
.. .

"Randy Replogle" wrote in message
...

a "scale".

...and this is a "miscalibrated rule" to allow for shrinkage in molded
parts.

In my apprenticeship theory class, the "scale" is the little black etched,
stamped or painted lines with the numbers which are on the "rule".

Interesting note, my instructor used to work for Rolls Royce and they used
to have their 6" rules calibrated once a year (or more, I forget the exact
cycle)...

Regards,

Robin