PCB construction question

[Bob Schrum]

The technique I've used is to design the PCB layout with holes on a 0.1 inch
grid as much as possible.  I use a "Sharpie" permanent marker to mark the holes
on a piece of 0.1" perfboard to indicate where the holes belong.  I drill larger
holes in the perfboard that match the PCB mount holes, then sandwich the etched
PCB between the perfboard and a piece of plywood, holding them together with
wood screws.  After putting in earplugs (pretty close work with a whining motor)
I lock the trigger on a handheld drill and follow the marked holes on the
perfboard.  BTW, I usually literally "break in" those little wire-gauge-sized
drill bits by putting them all the way into the drill chuck backwards and
breaking the shank off to shorten them, since they're usually so long that they
break after a dozen holes or so anyway!

Unfortunately, there are components that don't conform to a 0.1" grid.  They
tend to be pots, controls and jacks that require oversize holes requiring bit
changes and are not as tedious to do on a drill press or even a hand drill if
the hole marks are etched away so the drill won't "walk" off center.

____________________Reply Separator____________________
Subject:    PCB construction question
Author: John Speth <johns at oei.com>
Date:       4/2/98 5:32 PM

Hey all you PCB builders...

Lately I've found myself seriously considering making my own PCBs.  I've
identified 2 routes - 1) do the photomasking and etching myself (inexpensive but
messy) or 2) use a professional PCB fab service (very expensive but results are
+++).  In considering #1, I'm always faced with the big problem of How do I
drill the holes accurately?  I suppose a drill press would be the way to go but
one big mistake and the board's probably shot.  

So my question is to you who DIY your own PCBs, How do you drill so many holes
accurately?  Any hints or help offerered is greatly appreciated.  

Thanks...

John Speth
Object Engineering, Inc.
johns at oei.com