(Dan Caster) wrote in message om...
I looked in all my reference books and could only find data in the
Machinery Handbook on the size of drilled holes. Nothing on how
straight drilled hole can be expectd to be on a routine basis. And
obviously nothing on how straight a drilled hole can be expected to be
when done by a skilled machinest. Does anyone have some data on this?

So my question is when drilling a 1" deep .138 hole, how much should
one expect the far end of the hole to be from the ideal?

Dan

Hello Dan,
There is a military standard for drill hole size tolerances. It is
AND10387. See http://www.bjg-design.com/designbook/holest.htm
Also look at http://www.bjg-design.com/designbook/drilld.htm for drift
tolerance for drill holes. Also look up
http://www.bjg-design.com/designbook/formhsiz.htm for positional
tolerances.
Sy