I have a couple of small peices of CRS that need some 3/8" w x 3/8" deep
slots cut in them. Is it possible to do this at home with a 8" benchtop
drillpress and a cross slide table bolted to it? Accuracy is not overly
important, finish can be marginal but the nicer the better. Suggestions as
to what to use for a cutter that would fit in the drill chuck.

TIA

Dan

In article ,
"Dan" wrote:

I have a couple of small peices of CRS that need some 3/8" w x 3/8" deep
slots cut in them. Is it possible to do this at home with a 8" benchtop
drillpress and a cross slide table bolted to it? Accuracy is not overly
important, finish can be marginal but the nicer the better. Suggestions as
to what to use for a cutter that would fit in the drill chuck.

Not A Good Plan. Drill presses are not designed to retain the chuck when
it's subjected to side forces - the finish tends to stink when the chuck
comes loose. If you cannot (or it's fiscally silly to) get a mill, or
get time on a mill, drill a series of holes and grind/file the rest of
the slots.

--
Cats, Coffee, Chocolate...vices to live by

Well bud what if we move the part
alittle and bore stright down just take a little at at time???maybe .020 at a
time to be safe ???

Sounds like a good way to break a bit.
"HaroldA102" wrote in message
...

Well bud what if we move the part
alittle and bore stright down just take a little at at time???maybe .020
at a
time to be safe ???

waynemak wrote:
Sounds like a good way to break a bit.
"HaroldA102" wrote in message
...

Well bud what if we move the part
alittle and bore stright down just take a little at at time???maybe .020
at a
time to be safe ???



I slot virtually everything this way. Not in a press mind you but it
definitely reduces side loading.

On Tue, 14 Sep 2004 23:50:56 -0400, Stephen Young
vaguely proposed a theory
.......and in reply I say!:

remove ns from my header address to reply via email

How do you do it _without_ a press?


I think I know, but I'd rather be sailing! G
I slot virtually everything this way. Not in a press mind you but it
definitely reduces side loading.

************************************************** ***
I know I am wrong about just about everything. So I
am not going to listen when I am told I am wrong about
the things I know I am right about.

In article , HaroldA102 says...


Well bud what if we move the part
alittle and bore stright down just take a little at at time???maybe .020 at a
time to be safe ???

Using what, and end mill held in the jacobs chuck?

Large side loads on end mills when plunging.

Don't do it.

Jim


--
==================================================
please reply to:
JRR(zero) at pkmfgvm4 (dot) vnet (dot) ibm (dot) com
==================================================

On Wed, 15 Sep 2004 04:30:51 -0500, "Tim Williams"
calmly ranted:

"HaroldA102" wrote in message
...

Well bud what if we move the part
alittle and bore stright down just take a little at at time???maybe .020
at a
time to be safe ???

No, the bit bends and walks all over. You have to go over at least 3/4
diameters, and even then it might skip into the previous hole.

That's what I was thinking, but what would an end mill do?
It's cutting a flat hole which would be less prone to that.

----
- Nice perfume. Must you marinate in it? -
http://diversify.com Web Applications

Larry sez:
" That's what I was thinking, but what would an end mill do?
It's cutting a flat hole which would be less prone to that."

As far as being less prone to "skip", an end mill would be a little better
(but not much) for drilling straight down. Even then there are
uncontrollable side forces because of previous hole roughness, differing
texture in the metal, etc. And if the side forces don't get you, the design
of the end mill will . . . . that is to say; end mills make very poor
drills. We like to think of them as "good" drills but it just isn't true.
The end of a mill is designed for a plunge cut to get it into position for
"milling" - most of which occurs on the sides. Because of their design for
brief plunges, the ends of end mills have very poor chip clearances designed
into them. Extended "down" drilling will clog the cutting edges and destroy
the end mill via excessive heat. To be effective at all, a great deal of
peck drilling is required in order to not destroy the end mill - enough that
it is an inefficient way to proceed compared to a regular drill.

Bob Swinney


Larry Jaques" wrote in message
...
On Wed, 15 Sep 2004 04:30:51 -0500, "Tim Williams"
calmly ranted:

"HaroldA102" wrote in message
...

Well bud what if we move the part
alittle and bore stright down just take a little at at time???maybe .020
at a
time to be safe ???

No, the bit bends and walks all over. You have to go over at least 3/4
diameters, and even then it might skip into the previous hole.


----
- Nice perfume. Must you marinate in it? -
http://diversify.com Web Applications

There are at least three reasons why milling a slot with a drill
press/cross slide table is tough to do.
1. If you use an end mill in a regular drill chuck, the end mill
tends to pull itself out of the chuck. As it pulls out, your depth of
cut increases destroying the accuracy of the cut.
2. Many cross slide tables have a lot of slop in them and this can
cause real problems when the end mill contacts one side of the other of
the slot. It can chew up the slot and destroy the end mill.
3. (As already stated) the drill chuck may come loose from the spindle.
Solutions:
1. If you take light cuts and if the chuck is of good quality, you may
be able to live with this. An alternative is to locate a collet holder
that fits your drill press's taper, or the get a Weldon tool holder in
the size that fits your drill press taper on one end and fits the end
mill you need on the other.
2. When machinists need to cut an accurate width slot with an end mill,
they are supposed to use a narrower end mill than necessary. They cut
up one side edge of the slot, move over an appropriate amount and then
cut back down the other edge of the slot. If you think this out and
plan the cuts so that you take the table's backlash into account, you
can do the job.
3.If your drill press has a chuck with a threaded collar that holds
the chuck in place, this is not a problem.

All that said, I have done some end milling on my 15" Craftsman drill
press that is 40 years old. I have used end mills up to 3/8" diameter
and down to 1/8" diameter, using cutting depths of no more than .010" at
a pass. I have done this in both steel and in aluminum.

I know that I can act as a lightning rod for replies for saying this,
but if you plan to do much of this sort of thing, think about a small
mill drill. Harbor Freight has some on sale right now. I even saw one
at a flea market for $200 recently.

Pete Stanaitis
------------------

Dan wrote:

I have a couple of small peices of CRS that need some 3/8" w x 3/8" deep
slots cut in them. Is it possible to do this at home with a 8" benchtop
drillpress and a cross slide table bolted to it? Accuracy is not overly
important, finish can be marginal but the nicer the better. Suggestions as
to what to use for a cutter that would fit in the drill chuck.

TIA

Dan

Yup! I once did some milling in a drillpress, had all of the problems
others have mentioned. It worked, but not at all well.

I then got an Enco mill-drill. Huge improvement. They provide a lot of
capability for the buck.

You might or might not eventually outgrow a milldrill, but if you want to
mill slots now you almost certainly will want to do more milling in the
future. I made a lot of stuff on that milldrill, and I had no problem at
all selling the milldrill when I eventually found a good deal on a
Bridgeport.



"Pete & sheri" wrote in message
...


All that said, I have done some end milling on my 15" Craftsman drill
press that is 40 years old. I have used end mills up to 3/8" diameter
and down to 1/8" diameter, using cutting depths of no more than .010" at
a pass. I have done this in both steel and in aluminum.

I know that I can act as a lightning rod for replies for saying this,
but if you plan to do much of this sort of thing, think about a small
mill drill. Harbor Freight has some on sale right now. I even saw one
at a flea market for $200 recently.

Don sez:

"I made a lot of stuff on that milldrill, and I had no problem at all
selling the milldrill when I eventually found a good deal on a
Bridgeport."

I've still got mine. For a long time it sat in the back of my shop, mostly
unused after getting the big Bridgeport clone. The nearest other tool was a
20 inch drill press - until this week when I decided to exchange locations
between the drill press and the old mill drill. A mover's dolly and 2 floor
jacks were called upon to move the mill drill + stand about 15 feet into the
new spot. An old auto-type scissors jack came in handy for spot jacking up
onto the other movers. At the end, some 2-1/2 in. pipe was used to jockey
it into final position.

I hated to get rid of the mill drill, it had been a good tool for a long
time. It will see more service now that it is nearer to the business end of
my work bench and may catch some slop jobs not meant for the big mill. I've
been eyeing it for a long time as a pretty good basic tool for conversion
into a poor man's tool & cutter grinder.

Bob Swinney


"Don Foreman" wrote in message
...
Yup! I once did some milling in a drillpress, had all of the problems
others have mentioned. It worked, but not at all well.

I then got an Enco mill-drill. Huge improvement. They provide a lot of
capability for the buck.

You might or might not eventually outgrow a milldrill, but if you want
to
mill slots now you almost certainly will want to do more milling in the
future.


"Pete & sheri" wrote in message
...


All that said, I have done some end milling on my 15" Craftsman drill
press that is 40 years old. I have used end mills up to 3/8" diameter
and down to 1/8" diameter, using cutting depths of no more than .010" at
a pass. I have done this in both steel and in aluminum.

I know that I can act as a lightning rod for replies for saying this,
but if you plan to do much of this sort of thing, think about a small
mill drill. Harbor Freight has some on sale right now. I even saw one
at a flea market for $200 recently.

"Pete & sheri" wrote in message
...

locate a collet holder that fits your drill press's taper, or the get a
Weldon tool holder in the size that fits your drill press taper on one end
and fits the end mill you need on the other.

I think I tried all of the obvious places to search (mcmaster, msc, enco)
but didn't come up with anything that would work like this. All I could find
were male-to-male adapters. Were should I look?

Dan:

It _can_ be done, it is a pretty bad idea. I started my "machining" life
doing just such an operation, back when I had a Taig lathe. It was a bench
top Delta drill press. Things were going along "ok" when the end mill caught
an edge. That's when I learned first hand about the forces involved. The
spindle of the drill press bent, the now broken end mill walked across and
gouged the nearly finished piece (that's the way it works... isn't it?) and
the drill press spindle was toast. There simply isn't enough rigidity. The
stresses will flex everything. I'm not talking about deep cuts here, maybe
..020". That's a long, slow way to cut a slot 3/8" deep.

On the other hand, not everybody has the time, space, or money for anything
near an ideal situation. You don't mention how long the slot needs to be, or
if it's a blind slot. I'd endeavor to remove as much material as possible
through drilling first.

Good luck.

"Dan" wrote in message
. com...
I have a couple of small peices of CRS that need some 3/8" w x 3/8" deep
slots cut in them. Is it possible to do this at home with a 8" benchtop
drillpress and a cross slide table bolted to it? Accuracy is not overly
important, finish can be marginal but the nicer the better. Suggestions as
to what to use for a cutter that would fit in the drill chuck.

TIA

Dan

John Hofstad-Parkhill wrote:
"Dan" ... wrote ...
I have a couple of small peices of CRS that need some 3/8" w x 3/8" deep
slots cut in them. Is it possible to do this at home with a 8" benchtop
drillpress and a cross slide table bolted to it? Accuracy is not overly
important, finish can be marginal but the nicer the better. Suggestions as
to what to use for a cutter that would fit in the drill chuck.
....
You don't mention how long the slot needs to be, or if it's a blind slot.
I'd endeavor to remove as much material as possible through drilling first.

Drilling along the axis of the slot with a 3/8" bit would quickly
take out most of the material. Then if it's a through slot make 2
saw cuts and take the top off, leaving just quarter-rounds in the
bottom corners of the slot to finish with a file, mill, or grinder.
-jiw

Enco has MT2 to 1/4", 3/8", 1/2" with the tang or threaded
hole on the small end. I bought some from them a few years
ago. ~$19 ea. I think Harbor frieght might have them too.
www.machinetoolsdirect.net has the type with a female
thread in the small end in their latest print catalog. $17
each.

Eide wrote:

"Pete & sheri" wrote in message
...

locate a collet holder that fits your drill press's taper, or the get a
Weldon tool holder in the size that fits your drill press taper on one end
and fits the end mill you need on the other.

I think I tried all of the obvious places to search (mcmaster, msc, enco)
but didn't come up with anything that would work like this. All I could find
were male-to-male adapters. Were should I look?

In article ,
Robert Swinney wrote:

[ ... ]

texture in the metal, etc. And if the side forces don't get you, the design
of the end mill will . . . . that is to say; end mills make very poor
drills. We like to think of them as "good" drills but it just isn't true.
The end of a mill is designed for a plunge cut to get it into position for
"milling" - most of which occurs on the sides. Because of their design for
brief plunges, the ends of end mills have very poor chip clearances designed
into them.

And this is only *some* end-mills. Two-flute, three-flute, and
*some* four-flute have one flute which extends slightly past the center
to allow plunges.

Beyond that (such as six-flute ones) there is typically a
relieved center area with a center-drilled hole which was used to
position and stabilize it during the original sharpening. No flutes
extend to the center, and typically (based on memory) only go perhaps
2/3 of the way to the center.

Now -- if you need to plunge and make a slot, it is possible to
plunge *slowly* as you traverse, which will bring the inner ends of the
flutes to cut what was left by the cleared area, but if you plunge too
fast relative to the lateral travel, you will wind up sitting on the
flat center spot and be unable to make any more depth.

Enjoy,
DoN.
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