Ignoramus16885 wrote:

Like most people, I also believed that Morse tapers cannot hold any
tools with milling cutters.

Until tonight that is.

I was sorting through approx. 400 lbs of tooling when I discovered a
set of MT4 tapered endmill holders, from 3/4 to perhaps 1 3/8"
endmills. Also MT5 tapered shell mill holders.

No drawbar threads.

What gives?

I would think that MT4 and MT5 are serious machines that would not be
built for no good reason.

i


On 2010-03-25, DoN. Nichols wrote:

On 2010-03-24, danmitch wrote:

wrote:

[ ... ]


Here's Varmint Al's take:
http://www.varmintal.com/alath.htm#Milling_Attachment
The various bits are so low priced, you could make the attachment AND
get the mill/drill if that's what you wanted. I'd still make/buy a
drawbar setup for holding the milling cutters in the lathe, though,
mill shanks will walk out of chucks. Little Machineshop also has both
the drawbar and the "official" mini-lathe milling attachment.

Stan

Agreed that a drill chuks should NOT be used to hold milling cutters.
Most milling cutters have hardened shanks that a chuck will NOT grip
adequately. The cutters will slip and pul out under load. This can make
a real mess of the work, and is potentially quite dangerous to the
operator. It's a BAD idea, even if the chuck is secured with a drawbar.

There is an exception to this -- with chucks made by Albrecht
with diamond grit faced jaws which *can* grip a milling cutter shank
without slipping.

However -- these particular ones also don't come with Morse
Taper shanks, nor with Jacobs taper sockets. The come with integral R8
or 30, 40, or perhaps even 50 taper holders. I think that they are for
gripping solid carbide drill bits -- where even the shank is carbide. I
don't think that they advise using it for holding end mills anyway.


Collets, in good condition, properly seated, are usually acceptable for
holding milling cutters. This is especially true for small low powered
machines. An "End-Mill Holder" is certainly more secure, but can induce
small (usually not serious) runout problems.

Generally -- the runout is minimal with a Weldon shank end mill
in a quality end mill holder. The fit is so tight that you can create a
"pop" as it is drawn out if there is no through connection to the
drawbar for airflow.

And some of them are designed to be heated, and the shank put in
there at which point they shrink fit -- very strong grip, and
essentially no addition of runout.

Also -- for those in the UK and Australia -- look into Clarkson
collets. they are designed so the end mill *can't* be drawn out. The
end mill has a cylindrical shank with a threaded end and the holder has
a keyed nut which presses the center hole in the back of the end mill
against a center pip in the body of the holder. There is a collet
which tightens on the shank to maximize concentricity.

I've got some Clarkson holders -- but not any reasonable number
of matching end mills.


For light precision work, use collets ... for heavy work use end-mill
holders.

Yes -- because R8 collets (at least -- perhaps others) will let
the helical flute mills be drawn down under heavy cuts, resulting in a
cut which gets deeper as you go along -- and sometimes even continues
through the workpiece and into the mill's table. :-)

Enjoy,
DoN.

Well, a bigger Morse tape will hold a larger cutter BEFORE the cutting
forces make it come loose! :-((

These things DO exist (Morse and B&S tapers are all I've seen), and WERE
used, probably mostly a long time ago. I've seen a bunch of such
tooling, including milling cutters with integral Morse tapers, and NO
drawbar threads. IIRC, all these cutters had tanged tapers.

As I said earlier, it CAN work, sometimes, maybe, if the tapers are well
seated (probaly driven in with a mallet). If you've ever tried to
UN-seat a well seated Morse taper, you'll know just how tenacious these
self-locking tapers can be.

I expect their biggest weakness was in interrupted cuts, where the
hammering would tend to work them loose.

Today they're mainly a curiosity. I wouldn't recommend using them.
Considering what a mess a cutter can make if it slips and puuls out in a
collet, I can't immagine how bad it's be if they pulled out of a taper
during a heavy cut. It's surely wreck the cutter and work, and maybe
damage the machine.

The few M2 size I have mostly had soft enough shanks that I drilled and
tapped most for a 3/8 drawbar.

Dan Mitchell
============

Tod

--- news://freenews.netfront.net/ - complaints: ---

On Mar 25, 10:18*am, danmitch wrote:
...

Well, a bigger Morse tape will hold a larger cutter BEFORE the cutting
forces make it come loose! *:-((

...
I expect their biggest weakness was in interrupted cuts, where the
hammering would tend to work them loose.

Today they're mainly a curiosity. I wouldn't recommend using them.
Considering what a mess a cutter can make if it slips and puuls out in a
collet, I can't immagine how bad it's be if they pulled out of a taper
during a heavy cut. It's surely wreck the cutter and work, and maybe
damage the machine.

The few M2 size I have mostly had soft enough shanks that I drilled and
tapped most for a 3/8 drawbar.

Dan Mitchell

The B&S #7 taper holding that 2" shell mill is almost identical to
Morse #2.

When a cutter slips down in a collet it's still held tightly. The
Morse or B&S taper releases immediately, at least on my Clausing which
doesn't drive the tang.

I purposely popped the arbor in only by hand and pushed the cut until
the mill vibrated. The milled surface does not show where the arbor
released, there is only a small chip still attached to the far edge.
At that point the bevel no longer pushed the shell mill upwards.

The belts are loose enough to slip, what I meant by 'stalled'.

This was a test, not an endorsement of tanged cutters.

jsw

On 2010-03-25, danmitch wrote:
Well, a bigger Morse tape will hold a larger cutter BEFORE the cutting
forces make it come loose! :-((

These things DO exist (Morse and B&S tapers are all I've seen), and
WERE used, probably mostly a long time ago. I've seen a bunch of
such tooling, including milling cutters with integral Morse tapers,
and NO drawbar threads. IIRC, all these cutters had tanged tapers.

As I said earlier, it CAN work, sometimes, maybe, if the tapers are well
seated (probaly driven in with a mallet). If you've ever tried to
UN-seat a well seated Morse taper, you'll know just how tenacious these
self-locking tapers can be.

Took me at least a minute, and I had to get a 2 lb sledgehammer to get
one of those MT4 holders ouf of an MT5 adaptor.

I expect their biggest weakness was in interrupted cuts, where the
hammering would tend to work them loose.

Today they're mainly a curiosity. I wouldn't recommend using them.
Considering what a mess a cutter can make if it slips and puuls out in a
collet, I can't immagine how bad it's be if they pulled out of a taper
during a heavy cut. It's surely wreck the cutter and work, and maybe
damage the machine.

The few M2 size I have mostly had soft enough shanks that I drilled and
tapped most for a 3/8 drawbar.

I intuitively agree with you, but I must point out, these holders are
very obviously used and they were used a lot. They also look like they
have not seen crashes. I can take pictures if anyone is interested,
they are quite unusual.

i

On Mar 25, 11:36*am, Ignoramus30639 ignoramus30...@NOSPAM.
30639.invalid wrote:
...
Took me at least a minute, and I had to get a 2 lb sledgehammer to get
one of those MT4 holders ouf of an MT5 adaptor.

I made a cap that screws onto the top of the milling machine spindle
to push the loosened drawbar down and pop a collet without harming the
bearings.

jsw

Ignoramus30639 wrote:

On 2010-03-25, danmitch wrote:

Well, a bigger Morse tape will hold a larger cutter BEFORE the cutting
forces make it come loose! :-((

These things DO exist (Morse and B&S tapers are all I've seen), and
WERE used, probably mostly a long time ago. I've seen a bunch of
such tooling, including milling cutters with integral Morse tapers,
and NO drawbar threads. IIRC, all these cutters had tanged tapers.

As I said earlier, it CAN work, sometimes, maybe, if the tapers are well
seated (probaly driven in with a mallet). If you've ever tried to
UN-seat a well seated Morse taper, you'll know just how tenacious these
self-locking tapers can be.


Took me at least a minute, and I had to get a 2 lb sledgehammer to get
one of those MT4 holders ouf of an MT5 adaptor.


I expect their biggest weakness was in interrupted cuts, where the
hammering would tend to work them loose.

Today they're mainly a curiosity. I wouldn't recommend using them.
Considering what a mess a cutter can make if it slips and puuls out in a
collet, I can't immagine how bad it's be if they pulled out of a taper
during a heavy cut. It's surely wreck the cutter and work, and maybe
damage the machine.

The few M2 size I have mostly had soft enough shanks that I drilled and
tapped most for a 3/8 drawbar.


I intuitively agree with you, but I must point out, these holders are
very obviously used and they were used a lot. They also look like they
have not seen crashes. I can take pictures if anyone is interested,
they are quite unusual.

i
That's been pretty much my point all along. Just because something
doesn't conform to current practice, doesn't mean it was never done.
Current practice has been arrived at by long experience. It's usually
either what works best, or (still) works (maybe just barely) and is
least expensive, as best we know NOW.

A lot of things were done differently, and perhaps not wisely, in days
past. They didn't know what worked best back then (nor do we today),
just what worked adequately for the time.

And, once you accept that such practices existed, those who had to work
with them learned HOW to use them to maximum effect. In many old
industries you learned HOW to do something properly or got fired (or
died) early. Everyday practice back then would be considered totally
reckless today ... but they did it, they (usually) got the job done,
they built our industries and our nation (world), and even (often, but
not always) survived.

You also can't separate industrial practice from everyday living in it's
own time frame ... LOTS of things were dangerous back then, and many
people didn't live long for all sorts of reasons. Some of them may have
been safer at work than at home.

You do the best you can with what you've got.

Dan Mitchell
============

--- news://freenews.netfront.net/ - complaints: ---

Jim Wilkins wrote:

On Mar 25, 11:36 am, Ignoramus30639 ignoramus30...@NOSPAM.
30639.invalid wrote:

...
Took me at least a minute, and I had to get a 2 lb sledgehammer to get
one of those MT4 holders ouf of an MT5 adaptor.


I made a cap that screws onto the top of the milling machine spindle
to push the loosened drawbar down and pop a collet without harming the
bearings.

jsw
That's a good idea, assuming a hollow spindle. It saves the spindle
bearings from the jar of driving out the taper.

Recall that most of the Morse tooling I've seen is tanged. As most here
know, but some may not, the tang on such tools is NOT for driving the
cutter. It's nowhere near as strong in transferring torque as a properly
seated taper.

The tang is for ejecting the cutter from the taper using wedges inserted
through holes in the side of the spindle. This is most commonly applied
to drills, but it was obviously also was used with these milling cutters.

Dan Mitchell
============

--- news://freenews.netfront.net/ - complaints: ---

Recall that most of the Morse tooling I've seen is tanged. As most here
know, but some may not, the tang on such tools is NOT for driving the
cutter. It's nowhere near as strong in transferring torque as a properly
seated taper.

....and that is why the most common ER25 and ER32 MT2 collet chucks are
draw-bar equipped rather than made with a heat treated tang.
--


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
Production Tapping: http://Production-Tapping-Equipment.com/
Flagship Site: http://www.Drill-N-Tap.com
VIDEOS: http://www.youtube.com/user/AutoDrill

V8013-R

On 2010-03-25, danmitch wrote:
That's a good idea, assuming a hollow spindle. It saves the spindle
bearings from the jar of driving out the taper.

Recall that most of the Morse tooling I've seen is tanged. As most here
know, but some may not, the tang on such tools is NOT for driving the
cutter. It's nowhere near as strong in transferring torque as a properly
seated taper.

I have seen a lot of twisted off tangs.

The tang is for ejecting the cutter from the taper using wedges inserted
through holes in the side of the spindle. This is most commonly applied
to drills, but it was obviously also was used with these milling cutters.

Yep, those wedges are called drifts.

i

On 2010-03-25, danmitch wrote:
That's been pretty much my point all along. Just because something
doesn't conform to current practice, doesn't mean it was never done.
Current practice has been arrived at by long experience. It's usually
either what works best, or (still) works (maybe just barely) and is
least expensive, as best we know NOW.

A lot of things were done differently, and perhaps not wisely, in days
past. They didn't know what worked best back then (nor do we today),
just what worked adequately for the time.

And, once you accept that such practices existed, those who had to work
with them learned HOW to use them to maximum effect. In many old
industries you learned HOW to do something properly or got fired (or
died) early. Everyday practice back then would be considered totally
reckless today ... but they did it, they (usually) got the job done,
they built our industries and our nation (world), and even (often, but
not always) survived.

You also can't separate industrial practice from everyday living in it's
own time frame ... LOTS of things were dangerous back then, and many
people didn't live long for all sorts of reasons. Some of them may have
been safer at work than at home.

You do the best you can with what you've got.


I think that the take home lesson from this very interesting
discussion is as follows:

1) It is possible to use Morse taper tooling for milling, under
some conditions.
2) Despite that, the modern NMTB tooling is clearly much better.

I have also realized that, possibly, these toolholders were used for
straight shank drills, or hones, or something other than milling. That
would invalidate my point 1).

i

On Mar 25, 3:27*pm, danmitch wrote:
Jim Wilkins wrote:
...
The tang is for ejecting the cutter from the taper using wedges inserted
through holes in the side of the spindle. This is most commonly applied
to drills, but it was obviously also was used with these milling cutters.

Dan Mitchell

Neither my Clausing nor my Morse #3 horizontal mill have slots for the
drifts, or the parallel section that the tang engages. Both have
drawbars, at least, though the MT3 mill's arbor is threaded 1/2-12
(British pitch, American shape) rather than 1/2-13.

I suppose tolerating these quirks is the price of adopting unwanted
orphan machine tools. I acquire dogs the same way and they have turned
out well with some TLC.

jsw

On Thu, 25 Mar 2010 15:27:19 -0400, danmitch
wrote:


Recall that most of the Morse tooling I've seen is tanged. As most here
know, but some may not, the tang on such tools is NOT for driving the
cutter. It's nowhere near as strong in transferring torque as a properly
seated taper.

The tang is for ejecting the cutter from the taper using wedges inserted
through holes in the side of the spindle. This is most commonly applied
to drills, but it was obviously also was used with these milling cutters.

I don't buy the argument that the tang is meant only for separating
the taper. It'd be much simpler and cheaper to accomplish the same
thing with a reduced diameter at the small end of the taper, as seen
on lathe centers. I do agree that the tang shouldn't transmit torque
under normal circumstances, but think it's there to protect the taper
if it starts to slip. At least until things really go to hell and the
tang gets twisted off.

--
Ned Simmons

Ned Simmons wrote:

The tang is for ejecting the cutter from the taper using wedges inserted
through holes in the side of the spindle. This is most commonly applied
to drills, but it was obviously also was used with these milling cutters.

I don't buy the argument that the tang is meant only for separating
the taper. It'd be much simpler and cheaper to accomplish the same
thing with a reduced diameter at the small end of the taper, as seen
on lathe centers. I do agree that the tang shouldn't transmit torque
under normal circumstances, but think it's there to protect the taper
if it starts to slip. At least until things really go to hell and the
tang gets twisted off.


I think you are right, if a loosely seated drill, is drilling something where the chisel
point of the drill meets the stock first, the drill gets seated before too much torque is
applied.

Now when there is a decent sized starter hole, well, that tang may have a bad day when a
lot of torque gets applied before the drill has a chance to seat.

Wes