Homebrew PCBs

> It's the only sensible way to drill holes IMO. But drilling before
> etching makes no sense to me. CNC drilling seemed to have been high on
> wish lists in the group until the resident machinist declared that any
> backlash greater than .001" (or some similar nonsense from his
> textbook) just wasn't going to cut it. Surprisingly, he seems to still
> drill by hand.

The beauty of CNC is that if you do things properly, the amount of
backlash is actually irrelevant.

The secret is to ensure that you always approach the location from the
same side of the backlash. Then your holes will be very precisely
located (as precise as the leadscrew) regardless of the amount of
backlash.

-- 
Dave Hylands
Vancouver, BC, Canada
http://www.DaveHylands.com/