Note: apologies if this is a dupe; eternal september is living up to it's
name....

DoN. Nichols wrote:

Maybe -- maybe not. What is the nameplate RPM for that motor vs
the one currently in the drill press? If it is a 4-pole motor (a bit
below 1800 RPM) and the original was a 2-pole motor (a bit below 3600
RPM) you would gain slower operation as well. (Same for other
possible ratios of pole counts on the motors.

Hi Don, thanks for your response; they are both 1725s.

You're forgetting the tri-lobed holes from a standard drill bit
in thin metal which was mentioned earlier.

If I go with a twist bit, I will finish it up with a reamer, a tool which I
have always been eager to play with.

But if you insist on running one -- check whether the shank has
three partial flats on it. Without those, the bit is likely to bind
and the shank slip in the chuck.

Oh man tell me about it! This Delta of mine spins a 3/8" shiny finish when
it catches at the end of a hole, and drives me NUTS!

Unfortunate, too, because there is a S/D bit in my size for under $10 from
Amazon (the flatted one is a Milwaukee at fifty bucks and it got a bad
review). I might just try a round shank, and see if I can pound the key
enough to lock it in place.

You've already had one suggestion to use a Unibit, and I second
that. In case you don't know what they are -- they are a stepped
drill bit with a single flute which is self-guiding in the metal.
They come in various size ranges and step height. How thick is your
steel?

The steel is 11 gauge (0.12). I do know what a step-drill is, and actually
have one of the DrillMaster units from HF. I have always considered it to
be a bit for drilling out thin sheet metal; I originally purchased it for
making knob holes in a chassis.

That I have had more than a couple of suggestions to use one has garenerd my
attention, although I must admit a bit of skepticism as to whether or not it
is the right tool considering the number of holes (60 to 80) and the
thickness of material which I am looking to bore (1/8").

In any case -- instead of using water, I would suggest Rigid
high-sulfur thread cutting oil.

You won't have to remove as much metal at a pass as you would
with the Silver & Demming bit, so there is a greater chance that your
drill press will have sufficient torque -- with the above-mentioned
cutting oil refreshed for each hole. (Paint it on the unibit with an
acid brush or something similar.

Thanks for the suggestion, Don. I must admit that I really like water
because it is cheap and is easy to flow at a volume sufficient to cool the
bit and workpiece. I have used it before with good results in cooling, but
perhaps it is the lubrication ability of the bona fide product which makes
it shine.

Yes -- using the dowel pin to locate the already-drilled hole on
the other side makes sense.

Thanks, it seemed to be the logical solution. I appreciate the input.

Jon