Quote Originally Posted by BuffaloJohn View Post
It depends on many things, size of hole, printer parameters, etc, etc, etc... I stick to comon sizes and print tests to get it right. There is no magic formula...
I asked another designer today and he suggested I change the slicer to print exterior perimeters before the interior perimeters. Supposedly this reduces the tendency of imperfect interiors to squish the exteriors out of tolerance. I'll give it a try and see what happens.