&^%$#@( India.............

[Evan]

If the Morse Taper were such a powerhouse one must question why it sees such little application in the real world.

It has been superceded by better designs, in many cases, but not all. The industrial suppliers still stock Morse taper tooling so they must be selling it. Also, for an obsolete type why is it that everyone associated with the field knows at least the name Morse taper while others are unknown to many.

Incidentally, the KBC catalog has about 70 Morse taper line items with a total inventory of around 23,000 pieces. That's one heck of a pile of NOS for a product that isn't used much anymore.

[JCHannum]

I did not say that it was not in use. It is still used. However, it's most common application is on drills, which is what it was designed for and what probably acounts for the lion's share of those 70 line items. It is still also common in tailstock toolholding systems and some other light duty applications, but beyond those, it has largely been supplanted by other toolholding systems.

Interestingly, Atlas, well known ancient manufacturer of cheap, underpowered, pot metal geared home shop machines somehow felt compelled to equip the #2 MT arbor on their milling machine with a flanged driver which incorporates two drive pins to prevent slippage.

[J Tiers]

Interestingly, Atlas, well known ancient manufacturer of cheap, underpowered, pot metal geared home shop machines somehow felt compelled to equip the #2 MT arbor on their milling machine with a flanged driver which incorporates two drive pins to prevent slippage.

The MT2 is pretty undersized for a 3" or 4" cutter, I'd tend to agree with their decision.

While I claim that the friction is good enough for a drill of the taper size, I don't claim that there is NOTHING which might slip a taper.

That jammed taper would have driven anything up to "twist-off" torque, but it is hardly a practical situation.

There is quite a lot of difference between a tang drive and the drive via a flange. For the same force on the "key", a LOT more torque is transmitted by the flange due to the far larger diameter.

Does not remotely compare to a tiny tang of 1/6 the cutter diameter.

But, I have been under the impression that the Atlas drive flange was not quite what it seemed, that it clamped in some way to the arbor or spindle, and wasn't an integral part.

Also that it was not offered on all of the mills, but may have been an option. Pictures on the UK site don't show it in all pics, and in fact I didn't see it on any, although I know it existed.

Is that not correct?

[rantbot]

This statement -

From the 1959 Burghardt

"The purpose of the tang is to help drive the drill, since the hold of the taper alone is not sufficient."

is basically correct, but somewhat misleading.

The taper, unless grossly undersized for the drill, can transmit enough torque to drive any reasonable drill bit.

But in part of the drilling operation it tends to not hold well, because the axial load - necessary to provide enough friction force at the taper interface - is zero or negative during those operations ... as I mentioned above. At those times it would be nice to have another mechanism to drive the drill bit. It need not be a high-torque mechanism, but it should be one which doesn't rely on friction at the taper surface to do its job. A small tang would be adequate. The alternative is to bang the taper in hard, which means banging on the business end of the drill bit, which is damn near certain to lower the bit's efficiency as a cutting tool.

So the taper and the tang do their jobs at different times, and in different torque regimes.

My lathes don't happen to have tangs. They drill just fine, but the tapers do tend to pull out and disengage when I back the bits out of the holes. Tangs would be nice to prevent the drills or tailstock chucks from spinning. A drawbar arrangement would be even better, even though a drawbar wouldn't itself ever exert any driving torque; it would just keep the taper engaged. It wouldn't be needed when drilling, as the drill bit would then exert the force needed for the taper to exert whatever drive torque was needed.

[Renegade]

I don't post much... mostly sit back and read... you guys know most of it anyway.
I will add to lazlo's book listings by adding Machine Shop Practice volume 1 first printing 1979 by Karl H. Moltrect Ch.4 page 83 definitions of the various elements of a twist drill.

Tang-the flattened end of a tapered shank, intended to fit into a driving slot in a socket or machine spindle.

J Tiers
Quit beating a dead horse, it only makes it tougher to swallow.

Evan
Ditto the above, your intelligence at times is bewildering, put it to a better use.

Milacron
Your vile retorts suggest being spoiled as a child, If your married with children I pity them.

[lazlo]

I will add to lazlo's book listings by adding Machine Shop Practice volume 1 first printing 1979 by Karl H. Moltrect Ch.4 page 83 definitions of the various elements of a twist drill.

Yep, I've got both volumes of Moltrecht. They're my favorite of all of them.

I figured Moltrecht would have it described into there somewhere

[oldtiffie]

TS reaction

I read all of the opinions and issues (non-issues as well!!).

If my mechanics/physics is correct, there has to be a reaction to all of the torque/s generated here.

That should be no problem on a drill or a mill where most of the reactive force is on a spline and the drill tang, if it has one, is engaged by the slot for it in the spindle.

On the tail-stock of a lathe, the re-active forces are on either a single key (better/bigger lathes) or a small single cylindrical projection from a screw etc.

In all of this discussion to date there is no mention of the tail-stock quill retention devices let alone failure of any of them. So, either they are very good or the forces/torques are not as high as they might otherwise seem to be.

My lathe is a small 3-in-1 with an MT2 TS taper. I never put in a drill that cuts or enlarges a hole in a job in the head-stock by more than 1/4" - usually less. I usually start off with a 1/4" drill followed in succession by 3/8", 1/2" etc.

I am in no hurry at all - let alone in a rush to drill big holes in one go or to make chips at a commercial rate.

If I am in a rush or hurry, its time to either not go into the shop in the first place or to leave until the "rush" is over.

I use my shop to relax in - not to rush, "cut corners" or get stressed as those are recipes for an accident.

I am in a small HSM shop.

If I were in a commercial shop with "big" machines it might be different.

I am not sure that the taper under discussion is such a big source or reason for as much concern and heated debate as there is.

[JCHannum]

.......it was not offered on all of the mills, but may have been an option. Pictures on the UK site don't show it in all pics, and in fact I didn't see it on any, although I know it existed.

Is that not correct?

No, that is not at all correct. The spindle, change gears and Timken bearings from the 6" lathe were incorporated in the Atlas milling machine. The spindle nose was threaded and the driver threaded in place. A driver was furnished with each cutter arbor sold. The arbor also required a drawbar.

The Atlas manual states "The arbor driver is screwed on the spindle nose and the two prongs drive the cutter arbor". I know, I know, documented statements by manufacturers have no validity, but I thought I would point that out.

A shell end mill driver that threaded directly on the spindle was also available, as were straight arbors for angular cutters which used the driver. A draw in end mill holder with 1/2" capacity was available which did not have the drive flange, bushings were available for smaller tooling. This would set the max at 1/2" end mill for the MT#2.

The largest cutter they sold was 2-1/4" X 1. Diameter was limited by the overarm support, I don't know what that dimension is, but I would hazard a guess that 3" or 4" cutters were not in the design parameters. The recommended motor horsepower was 1/3 @ 1725RPM. It would appear they anticipated slippage even in this low power application.

Renegade, thanks for the Moltrecht reference. Moltrecht and Burghardt are among the best references and authorities available. I don't have any Moltrecht books at this time or he certainly would have been included.

[J Tiers]

odd that none of the pictures show it.

But I was correct, it threads on. I knew it wasn't an integral part.

In any case, with a large cutter 3 x the taper diameter, it was a smart move.

The tang, driver or not, is only 1/5 the cutter diameter, and would have no chance.

On my MT3 spindle, I have jammed 4" cutters, and had them slice a 1/4" key, with 1/4 HP input power.... So much for low power.......

But the taper never slipped.

I still say that IF the tang is intended to drive the drill, it is a stupid arrangement and would be better not depended on.

The mill setup is intelligent, and makes sense. TWO keys, at 5X the diameter, suggests the ability to take at least 10 x the torque.

[Milacron of PM]

I don't post much... mostly sit back and read... you guys know most of it anyway.
Milacron
Your vile retorts suggest being spoiled as a child, If your married with children I pity them.

So my statements such as
"Meaningless comment with a definite example to point to" is a "vile retort" but somehow your personal insult both to me and my family is not ? Such hypocrisy is astounding.

[torker]

So my statements such as
"Meaningless comment with a definite example to point to" is a "vile retort" but somehow your personal insult both to me and my family is not ? Such hypocrisy is astounding.

Don... piss off. Err.. Milacron (stupid name if you ask me). You are "supposed" to be the head of the large professional family but you just can't help coming over here stirring up **** with the little guys.
It makes me laugh when the newer guys around here defend you. They don't know you've been trying your best to stir the pot here for years.
You've shown your true colors yet again.
I've said it before.. you are a knowledgable fellow...too bad you choose to act like a jerk.
Russ

[JCHannum]

odd that none of the pictures show it.

But I was correct, it threads on. I knew it wasn't an integral part.

I still say that IF the tang is intended to drive the drill, it is a stupid arrangement and would be better not depended on.

The pictures on Tony's site do show it in place. They also show one with a dovetail cutter held in the endmill holder with the driver in place as a thread protector.

It is an integral part of the arbor installation and the instructions so describe. As with any machine, other options are available, and I mentioned all that are offered in the 1945 catalog.

Nobody said the tang is intended to drive the drill. It is intended to share the force with the taper, each adding it's own component. It was you and Evan who seemed to feel that the sole purpose of the tang was for removal. I merely presented documentation to the contrary.

[Milacron of PM]

Don... piss off. Err.. Milacron (stupid name if you ask me). You are "supposed" to be the head of the large professional family but you just can't help coming over here stirring up **** with the little guys.
It makes me laugh when the newer guys around here defend you. They don't know you've been trying your best to stir the pot here for years.
You've shown your true colors yet again.
I've said it before.. you are a knowledgable fellow...too bad you choose to act like a jerk.
Russ

Calm down and re read all I've written in this thread. Note that my first post in this thread was my opinion based on experience with tooing from India. Was that coming over here to stir up things ? No, it wasn't...obviously.

Now, think about my calling out Ramsey for illogical statements and suppositions as they pertained to JT's posts...just defending JT's position basically. Never any personal insults, just pointing out illogic. Even with Renegade's "vile" insults I refrain from attacking him personally. And now you..."stirring the pot", "stupid name", "jerk" more personal attacks....such a hypocrite.

Bottom line is I NEVER come over here "to stir the pot"....maybe I did years ago a few times but not now. I come over here when something that I know about catches my eye and I can't resist responding to it. I know a bit about Indian tooling, and that's why I began to post in this thread. The rest of it came about when Ramsey made his presumptions that irritated JT, and I simply defended/confirmed why JT should have been annoyed and it escalated from there.

[Evan]

It was you and Evan who seemed to feel that the sole purpose of the tang was for removal.

THAT IS NOT WHAT I SAID. To refresh your obviously failing memory here is what I said in post #44, the first time I mentioned it.

The tang is for removal. It's not hardened and will twist if allowed to take torque loads because of a poor fit of the taper in the socket. The reason it is made as a flat tang is to prevent spinning of the taper in case of looseness so that the spindle isn't damaged by such spinning, not to provide drive. It's a safety feature as well as a removal feature. It's better to damage the drill bit than the spindle.

Not only is removal not the SOLE purpose (which I have never said) but the purpose I explain makes a lot more sense in light of the fact that many machines don't make use of the tang and apparently don't need it.

[JCHannum]

THAT IS NOT WHAT I SAID. To refresh your obviously failing memory here is what I said in post #44, the first time I mentioned it.

The tang is for removal. It's not hardened and will twist if allowed to take torque loads because of a poor fit of the taper in the socket. The reason it is made as a flat tang is to prevent spinning of the taper in case of looseness so that the spindle isn't damaged by such spinning, not to provide drive. It's a safety feature as well as a removal feature. It's better to damage the drill bit than the spindle.

Not only is removal not the SOLE purpose (which I have never said) but the purpose I explain makes a lot more sense in light of the fact that many machines don't make use of the tang and apparently don't need it.

Sorry Evan, my memory is not failing at all, and it is a shame that you have to resort to veiled insults to validate your argument. Your post states "The tang is for removal." That is a pretty clear statement.

You continue that it is not hardened, which is not true in all cases, and follow with some nonsense about what happens if the tool becomes loose.

If you can present some factual data to verify that, we can add that to the use of the tang. Otherwise give it up.