According to Will :
"DoN. Nichols" wrote in message
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[ ... ]

Old US made drill presses are more likely to be satisfactory,
even if they need a bit of work at first.

I'm pretty clear on the spindle speeds needed, thanks to all of the great
information posted in this thread. Given that our holes would go between
1/4 and 1/2 inch, using 300 stainless, we seem to need about 300 to 800 rpm.

In the reverse order, of course -- that is the slower speed with
the larger drill bit. :-)

Given the requirement for using large pressing forces, and the need for
rigidity, what manufacturers and models do you think might be good
candidates?

To be honest -- I think that most import machines might be
marginal, and it is hard to find *new* machines form US makers that are
not really imports in disguise.

I would look for an older drill press of US manufacture. Go by
the diameter of the column. A benchtop machine with a column of 3-1/2"
diameter or greater should be plenty stiff. (Weight is rigidity.) And
you'll want to bolt it to the bench top while using it, even if you
unbolt it and store it later.

Obviously, look at the speeds available.

Honestly a very short model with a wide stable base would be
preferred by me, just because it could be easily stored under a rack in a
warehouse, or maybe floor mounted in the corner of a warehouse.

Hmm -- floor mounted would probably call for a 4" or greater
column diameter. If you get one of the 16-speed imports with the round
(and rotating) table, you may want to set up a 4x4 and a jack under the
center of the table, to take out the flex which is present on the arm
which reaches out to grip the center of the round table. This is
actually what I happen to have -- bought years ago, when the imports
were coming from Taiwan instead of China, and I find it to be too
flexible at times. But I don't have the budget to look for something
better, as it is hobby work for me.

Someone here had picked up a 2/3 HP Craftsman 10 inch drill press, which is
certainly short, and seems to be okay at 680 rpm for a 1/4 inch hole, but
probably doesn't cut it for anything much larger than 1/4 inch diameters.

Hmm ... how old a Craftsman? 10" drill press means only 5" from
center of drill bit to the column -- that sounds like the current cheap
imports which are selling on eBay for around $29.00 (but beware to check
out the shipping, which can be a killer.) a craftsman from the early
1970s or before would probably be pretty nice -- as long as you got
something capable of slower speeds.

Do you have any place nearby which sells used machine tools?
That is where I would check.

And I would suggest that you use split point high cobalt steel
bits for the task, instead of the more common HSS bits.

What advantages do those have?

The standard drill bit point is essentially two sort of curved
planes which meet in the center making a blunt chisel tip which does not
really cut, and has to be forced into the metal to get the edges of the
tip to cut.

A "split point" drill bit has four planes, not two. The first
two generate the main cutting edges and the relief angles, while the
second two cut more steeply back on the back of the first planes, and
are ground into the center of the bit, forming a second set of edges at
right angles to the first which go right to the center. So it takes
less force to drive the bit into the workpiece -- especially something
which likes to work harden if your feed slows down.

But -- get an envelope of whatever the standard quantity is from
someplace like MSC or a local industrial hardware store. (You probably
won't find them in most regular hardware stores.) Typical package sizes
will be something like ten or twelve for the 1/4" and smaller, and
perhaps drop to five or six for the sizes up to 1/2". Obviously, buy
just the sizes you need, and make sure to order more when you get down
to one or two left. (MSC is pretty good about quick delivery. I get
most things the next day if shipped from the Harrisburg PA warehouse.
(I'm just a bit south of Washington DC.) The Atlanta warehouse takes an
extra day, and I don't know what your shipping time would be.)

Anyway -- try the standard 1/4" bits and the split point ones in
some scrap of your stainless steel and see how different the feel is.

Oh yes -- the other advice about having a good way to clamp down
your workpiece is very good advice. If the bit grabs, it *will* spin
the workpiece, and has been known to inflict serious cuts.

Good Luck,
DoN.
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