Tim Wescott wrote:

On Fri, 16 Dec 2011 10:51:26 -0500, Jim Wilkins wrote:

"Joe AutoDrill" wrote in message
...
I measure about 8 degrees included angle on a fairly modern Stanley
bit. The old brace's chuck jaws suggest that anything will work as
long as one end is bigger than the other.
snip

The Stanley taper is 0.353/55" thick at the big end and 0.205/10" at
the small, about 1.12" away.

I haven't seen that nomenclature -- when you say 0.353/55", I assume that
the 0.353" means 353 thou -- but what does the '/55' mean?

Perhaps 0.353/55" means 0.353"-0.355"?