On Mon, 20 Oct 2003 07:14:51 -0500, "Alan Kamrowski II"
wrote:

Hi,

I am going to need to drill a 2 1/4" and 10 or so 1 1/8" holes in a metal
control panel (for an arcade game). I'm not sure how thick the control
panel is, but I wouldn't think thicker than 1/8". My understanding that it
will arrive to me "powder coated" which I'm not sure will complicate things
or not. I have a drill press and plan (so far) to drill using a lenox
bimetal hole saw. I plan to put some wood behind the control panel while
drilling it.

You need to know the thickness and what kind of metal it is -- steel
or aluminum.

Flycutting steel with a single-point tool is possible, but It takes a
very rigid setup, a rigid tool and a hefty drillpress -- or better, a
mill or mill-drill. If something moves and the tool "digs" or
catches, all hell can break loose.

One way to do it is to make rough holes anywhich way you can, even
with a sabersaw aka jigsaw. Also, make a good hole of the right
size to serve as a guide (could even be wood or masonite) and then
use a roto-zip, router or pneumatic diegrinder with bit appropriate
for the material to smooth up the hole. With steel use a carbide
burr. For aluminum, use a carbide routerbit or HSS endmill; carbide
burrs will load up with aluminum. Your chances of wrecking the panel
are much less this way, it goes surprisingly fast and it leaves a
surprisingly smooth hole.

I just today made some 4.5" dia holes in 1/4" plexiglass. I
rough-cut them with a sabersaw and then shaved them out to size with a
flycutter, enlarging the diameter 50 thou with each pass. Only took
two passes. Holes look like they grew the clean sharp edges with
no chippping.