Should a drill press used for drilling holes through 1/4 inch stainless
steel have any different characteristics than a drill press used for wood
work? Our applications are fairly trivial: maybe once a month we would
need to drill new screw placement holes in thick stainless retaining plates.
So we need a small drill press, but I want to make sure we don't overlook
any specific characteristics that a drill press intended for metal use
should have.

--
Will

depends what diameter drill your spinning, but metal drilling needs to go
slower than wood.
bigger drills, more slower, once you go past 1/2" dia. drilling in metal,
you really need to slow down. Drill presses made for woodworking are
generally unsuitable for holes in metal larger than 1/4" dia, unless you
like sharpening & replacing drill bits alot.


"Will" wrote in message
...
Should a drill press used for drilling holes through 1/4 inch stainless
steel have any different characteristics than a drill press used for wood
work? Our applications are fairly trivial: maybe once a month we would
need to drill new screw placement holes in thick stainless retaining
plates. So we need a small drill press, but I want to make sure we don't
overlook any specific characteristics that a drill press intended for
metal use should have.

--
Will

"Tony" wrote in message
...
depends what diameter drill your spinning, but metal drilling needs to go
slower than wood.
bigger drills, more slower, once you go past 1/2" dia. drilling in metal,
you really need to slow down. Drill presses made for woodworking are
generally unsuitable for holes in metal larger than 1/4" dia, unless you
like sharpening & replacing drill bits alot.

That is great information. What are the specific characteristics I should
call out? 1/4 to 1/2 inch diameters would be a very typical range for us.

--
Will


"Will" wrote in message
...
Should a drill press used for drilling holes through 1/4 inch stainless
steel have any different characteristics than a drill press used for wood
work? Our applications are fairly trivial: maybe once a month we would
need to drill new screw placement holes in thick stainless retaining
plates. So we need a small drill press, but I want to make sure we don't
overlook any specific characteristics that a drill press intended for
metal use should have.

--
Will

"Tony" wrote in message
...
depends what diameter drill your spinning, but metal drilling needs to go
slower than wood.
bigger drills, more slower, once you go past 1/2" dia. drilling in metal,
you really need to slow down. Drill presses made for woodworking are
generally unsuitable for holes in metal larger than 1/4" dia, unless you
like sharpening & replacing drill bits alot.

Drilling "thick" stainless, you have no chance in hell with a drill press
that runs at woodworking speeds. You'll burn every bit even at the low speed
end. Also, you have little chance with 1/4" bits in "thick" stainless unless
you have a pretty rigid drill press that can run at very moderate
metalworking speeds. Somebody here will know the specific RPM, but it's 'way
down there.

A drill press that will cover the appropriate speeds for both is a not very
common. My floor model 50-year-old Walker-Turner, which is belt-driven, will
just do it, but it's because I have the intermediate pulley ("third wheel")
option for it. It's just barely rigid enough for drilling stainless with a
1/4" bit, partly because I had a lot of experience drilling many hundreds --
probably thousands -- of stainless pieces when I worked in a shop. It
requires some practice to keep adequate pressure on the bit without
springing the whole affair or slipping the belt, unless the drill press is a
heavy industrial model. If you don't keep adequate pressure (feed pressure,
that is) on it, you'll work-harden the stainless, burn the bit, and make it
extremely difficult to get the hole re-started.

The best bet in a commercial setting is to have one drill press appropriate
for each task. In fact, I prefer drilling thick stainless in a Bridgeport or
other mill.

--
Ed Huntress



"Will" wrote in message
...
Should a drill press used for drilling holes through 1/4 inch stainless
steel have any different characteristics than a drill press used for wood
work? Our applications are fairly trivial: maybe once a month we would
need to drill new screw placement holes in thick stainless retaining
plates. So we need a small drill press, but I want to make sure we don't
overlook any specific characteristics that a drill press intended for
metal use should have.

--
Will

Ed Huntress writes:

A drill press that will cover the appropriate speeds for both is a not
very common.

My Delta woodworking drill press goes down to 250 rpm. Home Depot item
from about 1996, with a 3-pulley system and 1720 rpm motor.

For a half inch drill bit in stainless you want a drill press that will go
as slow as 300 rpm. Most better quality woodworking drill presses can go
that slow.
A gearbox driven drill press gets very expensive but for half inch and
less you could get by with a vee belt driven drill press.
1/3 horsepower motor would be on the weak side.. look for an honest half
horsepower motor.
Randy


"Will" wrote in message
...
"Tony" wrote in message
...
depends what diameter drill your spinning, but metal drilling needs to go
slower than wood.
bigger drills, more slower, once you go past 1/2" dia. drilling in metal,
you really need to slow down. Drill presses made for woodworking are
generally unsuitable for holes in metal larger than 1/4" dia, unless you
like sharpening & replacing drill bits alot.

That is great information. What are the specific characteristics I
should call out? 1/4 to 1/2 inch diameters would be a very typical range
for us.

--

"Richard J Kinch" wrote in message
. ..
Ed Huntress writes:

A drill press that will cover the appropriate speeds for both is a not
very common.

My Delta woodworking drill press goes down to 250 rpm. Home Depot item
from about 1996, with a 3-pulley system and 1720 rpm motor.

You've got the rpm covered. How does it do in thick stainless with a 0.25"
bit?

--
Ed Huntress

"Richard J Kinch" wrote in message
. ..
Ed Huntress writes:

A drill press that will cover the appropriate speeds for both is a not
very common.

My Delta woodworking drill press goes down to 250 rpm. Home Depot item
from about 1996, with a 3-pulley system and 1720 rpm motor.

I meant to ask, how does it do in stainless with a 0.5" bit? That's really
pushing it in thick stock, with a woodworking drill press. My Walker-Turner
won't do it, even though it has the right rpm. I have squeaked through with
3/8" bits, after drilling an 1/8" pilot hole. But that's not the way to go
for commercial work.

--
Ed Huntress

Ed Huntress writes:

I meant to ask, how does it do in stainless with a 0.5" bit?

I've managed into 304 stainless. Also 7/8" in hot rolled 1018 steel.

On Tue, 30 Oct 2007 19:09:41 -0700, "Will"
wrote:

Should a drill press used for drilling holes through 1/4 inch stainless
steel have any different characteristics than a drill press used for wood
work? Our applications are fairly trivial: maybe once a month we would
need to drill new screw placement holes in thick stainless retaining plates.
So we need a small drill press, but I want to make sure we don't overlook
any specific characteristics that a drill press intended for metal use
should have.

It is really handy to have T-slots milled into the table so that you
can mount a vise or jigs to it. Wood doesn't tend to spin as much as
metal when drilling, and it causes less damage when it does, so that
feature is often overlooked on the woodworking DPs, where the work is
easily held by hand.

Will wrote:


That is great information. What are the specific characteristics I should
call out? 1/4 to 1/2 inch diameters would be a very typical range for us.


Dig up the recommended cutting speed in surface feet per minute, for
the materials you are cutting, and the drill materials you are using,
and start from there.

Too fast cooks drills, too slow cost you time.

Some materials are just nicer to work with, too, and are less picky
about speeds and feeds. 304 is not one of those, for example.

Cheers
Trevor Jones

Trevor Jones writes:

Will wrote:


That is great information. What are the specific characteristics I
should call out? 1/4 to 1/2 inch diameters would be a very typical
range for us.


Dig up the recommended cutting speed in surface feet per minute, for
the materials you are cutting, and the drill materials you are using,
and start from there.

Can you point to a good source for this information? I'd like to do
better than my normal "hmm, this drill is about so big, guess I'll run
in second notch this time".

The nomenclature is 'speed(s) and feed(s)'; here's one:
http://www.whitney-tool.com/html/cal...SpeedFeed.html

David Merrill

"Joe Pfeiffer" wrote in message
...
Trevor Jones writes:

Will wrote:

Dig up the recommended cutting speed in surface feet per minute, for
the materials you are cutting, and the drill materials you are using,
and start from there.

Can you point to a good source for this information? I'd like to do
better than my normal "hmm, this drill is about so big, guess I'll run
in second notch this time".

On Oct 31, 12:38 pm, "David Merrill" wrote:
The nomenclature is 'speed(s) and feed(s)'; here's one:http://www.whitney-tool.com/html/cal...SpeedFeed.html

David Merrill

"Joe Pfeiffer" wrote in message

...

Trevor Jones writes:

Will wrote:

Dig up the recommended cutting speed in surface feet per minute, for
the materials you are cutting, and the drill materials you are using,
and start from there.

Can you point to a good source for this information? I'd like to do
better than my normal "hmm, this drill is about so big, guess I'll run
in second notch this time".

This info is available in the American Machinist's Handbook. My copy
is over 40 years old.

Machinerys Handbook may have it, also.

Or try a text book from a technical college on machine tool operation.

IIRC this topic was discussed in this forum not too long ago (last
year?) try searching for it.

If you get stuck re-state your question here and we will see what we
can do.

Wolfgang

"David Merrill" writes:

The nomenclature is 'speed(s) and feed(s)'; here's one:
http://www.whitney-tool.com/html/cal...SpeedFeed.html

Thanks! Exactly what I was looking for.

"David Merrill" wrote in message
news:vc2Wi.179798$Fc.10546@attbi_s21...
The nomenclature is 'speed(s) and feed(s)'; here's one:
http://www.whitney-tool.com/html/cal...SpeedFeed.html

For cutting 1/4 inch stainless (let's say 300 series) which of the bit types
should we be preferring:

- high speed steel
- uncoated carbide
- coated carbide

If it matters, then let's assume that the application is drilling 1/4 inch
diameter holes in the 300 series stainless plates that are about 1/4 inch
thick.

--
Will


"Joe Pfeiffer" wrote in message
...
Dig up the recommended cutting speed in surface feet per minute, for
the materials you are cutting, and the drill materials you are using,
and start from there.

Trevor Jones writes:
Can you point to a good source for this information? I'd like to do
better than my normal "hmm, this drill is about so big, guess I'll run
in second notch this time".

I'd buy a quality machine - one that can change spindle speed from metal
rates - slow to those of faster wood rates. Some wood is slow. But when
using it as a shaper and and such - it is fast.

The 1/4" Stainless is not a trivial task. Make sure you have ample clamping
ability to hold the work tight. A catch can whip a sheet or bar and
really spoil a day of someone.

A nice large flat table and an adjustable speed - belts are ok - you say
once a month change the belts for a job. Cheaper than electronics, but
not as handy.

Martin H. Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
TSRA, Life; NRA LOH & Patron Member, Golden Eagle, Patriot's Medal.
NRA Second Amendment Task Force Charter Founder
IHMSA and NRA Metallic Silhouette maker & member.
http://lufkinced.com/


Will wrote:
Should a drill press used for drilling holes through 1/4 inch stainless
steel have any different characteristics than a drill press used for wood
work? Our applications are fairly trivial: maybe once a month we would
need to drill new screw placement holes in thick stainless retaining plates.
So we need a small drill press, but I want to make sure we don't overlook
any specific characteristics that a drill press intended for metal use
should have.


----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups
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On Wed, 31 Oct 2007 17:09:15 -0700, "Will"
wrote:

"David Merrill" wrote in message
news:vc2Wi.179798$Fc.10546@attbi_s21...
The nomenclature is 'speed(s) and feed(s)'; here's one:
http://www.whitney-tool.com/html/cal...SpeedFeed.html

For cutting 1/4 inch stainless (let's say 300 series) which of the bit types
should we be preferring:

- high speed steel
- uncoated carbide
- coated carbide

If it matters, then let's assume that the application is drilling 1/4 inch
diameter holes in the 300 series stainless plates that are about 1/4 inch
thick.


High Speed Steel.

Working stainless is not the "nearly impossible" task that some people
seem to think it is. I've been machining stainless since the 1950's
using high speed steel tooling with no problems.

There are two areas you need to address in machining stainless -
cutting speed, and feed rate. As a general statement you want the
proper cutting speed (RPM), or a little slower, and the highest feed
that the tool will handle.

For a 1/4"HSS drill, look up the cutting speed for HSS and the
stainless alloy you are using.
300 series 50 - 70 FPM. Using the lower speed the drill RPM will be:

50 X ((12/(Pi X D))

50 X (12/(3.1416 X 0.25)) = 763 RPM - set the drill press for that
speed or slower

Now use as high a pressure on the drill press handles that the drill
bit will stand. The chips will come off the work as spirals and may be
a light brown; if they are dark brown or blue slow the RPM.

As the drill starts to break through the bottom you should be able to
feel it and lighten up on the pressure just a bit. If you can't feel
the drop in pressure just use a piece of wood as a backing block until
you get the feel.

When people refer to stainless as being hard it is rather that
stainless work hardens very rapidly. Letting your drill spin without
cutting for just a second results in a work hardened surface that the
drill can no longer cut.

The thing you want to remember above all else is "keep the speed low
and the feed high" and you'll find that drilling stainless is no more
difficult then drilling mild steel.


Bruce-in-Bangkok
(Note:displayed e-mail
address is a spam trap)

On Tue, 30 Oct 2007 22:40:12 -0400,

"Will" wrote in message
m...
Should a drill press used for drilling holes through 1/4 inch stainless
steel have any different characteristics than a drill press used for wood
work? Our applications are fairly trivial: maybe once a month we would
need to drill new screw placement holes in thick stainless retaining
plates. So we need a small drill press, but I want to make sure we don't
overlook any specific characteristics that a drill press intended for
metal use should have.

"Tony" wrote:
depends what diameter drill your spinning, but metal drilling needs to go
slower than wood.
bigger drills, more slower, once you go past 1/2" dia. drilling in metal,
you really need to slow down. Drill presses made for woodworking are
generally unsuitable for holes in metal larger than 1/4" dia, unless you
like sharpening & replacing drill bits alot.

I have a cheapo YingTong drill press, 2MT, 16mm chuck, 16 speeds.
I only run it at 200 ? rpm ( lowest speed), no matter what size drill
bit, 3mm to 25mm in steel or wood, 6mm to 70mm in Forstner bits (wood)
or up to 150mm holesaw in steel or wood. I am just too lazy to
change the belt on the pulleys. Works for me.
Most important is to check runout on the chuck, mine is negligible.

Alan

Can you point to a good source for this information? I'd like to do
better than my normal "hmm, this drill is about so big, guess I'll run
in second notch this time".

I've got it on one of my sites... All very conservative numbers with
coolant factored in.

http://www.multi-drill.com/drill-speed-chart.htm

Stainless really should never be drilled without coolant.... Unless you can
spin at 2 RPM.

Regards,
Joe Agro, Jr.
(800) 871-5022
01.908.542.0244
Automatic / Pneumatic Drills: http://www.AutoDrill.com
Multiple Spindle Drills: http://www.Multi-Drill.com

V8013-R

On Oct 31, 5:09 pm, "Will" wrote:
"David Merrill" wrote in message

For cutting 1/4 inch stainless (let's say 300 series) which of the bit types
should we be preferring:

- high speed steel
- uncoated carbide
- coated carbide

For hand-feed on a drill press, stay away from carbides. They work
much
better under controlled power feed. Cobalt HSS will give better life
than
standard HSS, but for your application, the difference probably
wouldn't
be noticeable. In a production setting of hundreds of holes, the
lifetime
issue is more important. Carbides will chip easily due to their
brittleness,
and hand-feed can certainly demonstrate that. HSS can absorb shock
from inconsistent hand-feed much better.

According to Will :
Should a drill press used for drilling holes through 1/4 inch stainless
steel have any different characteristics than a drill press used for wood
work?

Yep -- spindle speed. You need to run slower in steel than in
wood, and even slower in stainless steel (depending on which stainless,
some are more touchy than others.)

And -- you want the machine to be more rigid, as you will need
to apply more force to keep the drill bit cutting -- pause with too
little force and the bit stops cutting and work hardens the workpiece,
making it *very* difficult to get the bit started cutting again -- even
if you replace it with a new sharp one.

The actual speed, and actual force needed are a function of the
diameter of the hole, which you have not yet specified.

Our applications are fairly trivial: maybe once a month we would
need to drill new screw placement holes in thick stainless retaining plates.
So we need a small drill press, but I want to make sure we don't overlook
any specific characteristics that a drill press intended for metal use
should have.

Post the maximum diameter hole you will need to make, and which
stainless steel, and we can calculate the highest spindle speed which
you can use. The cheap import 5-speed ones typically won't go slow
enough, except for the smaller holes (say 1/8" or smaller. The somewhat
larger (still cheap) floor standing ones with 16 speeds (lots of pulley
slots and two belts) will probably go slow enough, but with a large
hole, they are not rigid enough, and once you start your hole, the
needed force will cause the table to bend down a bit, making your hole
not perpendicular to the surface of the workpiece.

Almost all of the import drill presses will not go slow enough
to use the maximum size bit which the supplied chuck will hold for
drilling through plain steel, let alone through stainless steel.

So -- the stainless steel alloy number (e.g. 304) will allow us
to look up the proper SFM (Surface Feet per Minute) with HSS (High Speed
Steel) bits.

Once we have that, knowing the largest hole diameter needed, we
can calculate the maximum spindle speed for that diameter, and this will
let you look up what the drill press you are considering will offer, and
see if it is slow enough.

Smaller holes are typically no problem as long as you can handle
the largest hole you need to drill.

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

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

Good Luck,
DoN.
--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

According to Will :
"David Merrill" wrote in message
news:vc2Wi.179798$Fc.10546@attbi_s21...
The nomenclature is 'speed(s) and feed(s)'; here's one:
http://www.whitney-tool.com/html/cal...SpeedFeed.html

For cutting 1/4 inch stainless (let's say 300 series) which of the bit types
should we be preferring:

- high speed steel

Add "high cobalt steel"

- uncoated carbide
- coated carbide

The carbides have the disadvantage of being very brittle, and
can break if there is any side force while you're drilling.

High Cobalt Steel gives you a bit tougher steel than the
standard HSS, without being as brittle as the carbide bits.

If you are drilling a *lot* of holes, perhaps the coated version
of the cobalt steel would be better, and it might be worthwhile
consulting one if the major manufacturers to find out what works best
with the alloy you are drilling.

You also want coolant on the bit while you are drilling.

If it matters, then let's assume that the application is drilling 1/4 inch
diameter holes in the 300 series stainless plates that are about 1/4 inch
thick.

Which 300 series steel? 304 is a lot nastier to work with than
303.

All of the figures are in _Machinery's Handbook_, among other
references. (And there are even nomogram slide rules for selecting the
proper (maximum) drill speed. As has already been mentioned, too fast
will burn up the bits rapidly, too slow only costs you time. If you are
not drilling a lot of holes all of the time, it won't hurt to run too
slow, and you'll gain a bit of bit life. Those maximum speeds are based
on a tradeoff of cost of machinist's time vs cost of replacement drill
bits.

And having the bits sharpened as "split point" will let you keep
drilling with somewhat less force than a standard chisel-point drill bit
will require -- which helps a cheaper machine do the job.

Proably for 1/4" holes, even one of the cheaper bench-top drill
presses will do -- if the motor can handle it. (Often the import drill
presses have shall we say "optimistically marked" horsepower ratings, and
often burn out quickly with serious use -- after which you replace it
with a *good* motor. :-)

Good Luck,
DoN.

--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

"DoN. Nichols" wrote in message
...
According to Will :
Post the maximum diameter hole you will need to make, and which
stainless steel, and we can calculate the highest spindle speed which
you can use. The cheap import 5-speed ones typically won't go slow
enough, except for the smaller holes (say 1/8" or smaller. The somewhat
larger (still cheap) floor standing ones with 16 speeds (lots of pulley
slots and two belts) will probably go slow enough, but with a large
hole, they are not rigid enough, and once you start your hole, the
needed force will cause the table to bend down a bit, making your hole
not perpendicular to the surface of the workpiece.

Almost all of the import drill presses will not go slow enough
to use the maximum size bit which the supplied chuck will hold for
drilling through plain steel, let alone through stainless steel.
...
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.

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

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.


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?

--
Will

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

[ ... ]

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.
--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

On Nov 1, 1:24 pm, "Joe AutoDrill" wrote:
...
http://www.multi-drill.com/drill-speed-chart.htm
...
Joe Agro, Jr.

I printed spreadsheet charts like this to hang behind my lathe and
mill, showing the RPM for each belt position and the resulting cutting
speed for common diameters.

If I want to drill a 12mm hole in hot-rolled, for example, I look in
the 0.500" row for the highest pulley setting under 80-100 Feet per
Minute.

Quick, simple, keeps oily fingers off the calculator.

On Nov 1, 9:20 pm, "Will" westes-...@noemail.


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?

Much info is already here on this subject, but as a piece of practical
information: The most common configuration of cobalt HSS drill bit
seems to be the 135-degree split point, which is what you should
look for. The split point is indeed best for the application, and has
tha added benefit of being able to self-center more accurately. These
bits are available as well in screw machine length (shorter than
jobber
length), which makes them more rigid and less apt to wander.

According to Jim Wilkins :

[ ... ]

I printed spreadsheet charts like this to hang behind my lathe and
mill, showing the RPM for each belt position and the resulting cutting
speed for common diameters.

[ ... ]

Quick, simple, keeps oily fingers off the calculator.

Yes -- though I have another way to accomplish that last goal.
I keep the calculator in a Ziploc baggie, facing the back side, so there
is no label in the way of reading the display or identifying the
keytops.

Enjoy,
DoN.

--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

On Tue, 30 Oct 2007 19:09:41 -0700, "Will" wrote:

Should a drill press used for drilling holes through 1/4 inch stainless
steel have any different characteristics than a drill press used for wood
work? Our applications are fairly trivial: maybe once a month we would
need to drill new screw placement holes in thick stainless retaining plates.
So we need a small drill press, but I want to make sure we don't overlook
any specific characteristics that a drill press intended for metal use
should have.


To add my comments to the many good ones that have appeared:-

If you can find a drill press with power down feed, you will find that it
gives better results and drill life. Especially if you have to go to 1/2" or
larger in 303.

Woodworking drills often seem to have table mountings that are lighter than is
desirable. I have a woodworking drill (12", open slot, round table, 3"
pillar) and a metalworking drill (12", closed T slot, square table, 2 1/2"
pillar) and it's quite worrying how much the lighter table on the woodworking
drill moves when you lean into a 1/2" or larger drill in steel. Having said
that, the woodworking drill is where I can use it easily and the other drill
doesn't get used very often :-)

If the motor struggles with the monthly metal jobs, don't forget that a pilot
hole, about the diameter of the main drill's web, will make the main drill cut
far more easily.

Mark Rand
RTFM

"Mark Rand" wrote in message
...
On Tue, 30 Oct 2007 19:09:41 -0700, "Will"
wrote:

Should a drill press used for drilling holes through 1/4 inch stainless
steel have any different characteristics than a drill press used for wood
work? Our applications are fairly trivial: maybe once a month we would
need to drill new screw placement holes in thick stainless retaining
plates.
So we need a small drill press, but I want to make sure we don't overlook
any specific characteristics that a drill press intended for metal use
should have.


To add my comments to the many good ones that have appeared:-

If you can find a drill press with power down feed, you will find that it
gives better results and drill life. Especially if you have to go to 1/2"
or
larger in 303.

Do you have any specific brands and models to recommend?

--
Will