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
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