Morse tapers

[Mark Gould 1Participant @markgould1]

[Mark Gould 1Participant @markgould1]

Gents,

I have been using MT tooling for a few years now and have recently run into doubts about whether or not I am using it correctly. Please let me know if this is correct:

When using MT tooling without a drawbar (like a drill chuck) I whack the tapered shank up into the spindle and drill my holes. No worries there.

When using MT tooling that requires a drawbar (like a collet chuck or slitting saw arbor) however I do it differently. I lightly hold the taper and insert the drawbar and use the drawbar to pull the taper in until tight. Should I be whacking this in too and using the drawbar only to keep it from falling out?

Thanks in advance,

Mark

[Michael GilliganParticipant @michaelgilligan61133]

The Morse Taper is designed to be ‘self holding’ … I would generally avoid ‘whacking’ it into place whether using drills or tool-holders !!

If the taper slips, look to the accuracy of the fit NOT the hammer collection.

MichaelG.

[David George 1Participant @davidgeorge1]

Hi what machine are you using I presume a mill and is there a slot in the spindle to eject the drill with a drift or other means of ejecting tooling. If you use a milling type tooling with side ways load you should always use a drawbar. On my mill I use a drawbar for all tooling as the drawbar is captive and it ejects tooling as you unscrew.

David

[Mark Gould 1Participant @markgould1]

Hi and thanks for your answers,

Michael, by whacking I mean engaging the taper in the spindle. This is done by hand, not with any percusive violence! No tools involved Having said that, I am aware that MT tooling is supposed to be self holding but surely not a milling cutter in a collet chuck? Perhaps i should have added that my question relates to operation with a milling machine.

David, it is an Emco FB-2 mini mill. Ejecting a drill chuck is via a pushbar from the top. I hold the spindle with a crappy spanner and turn the top not up on the Top of the spindle to eject the chuck. (I am milling Graham Meeks spindle lock this week to solve this irritation)

Thanks again,

Mark

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Mark Gould 1 on 08/05/2020 08:40:12:

Hi and thanks for your answers,

Michael, by whacking I mean engaging the taper in the spindle. This is done by hand, not with any percusive violence! No tools involved Having said that, I am aware that MT tooling is supposed to be self holding but surely not a milling cutter in a collet chuck? Perhaps i should have added that my question relates to operation with a milling machine.

.

In a milling situation … self-holding to the extent of carrying the drive torque

The draw-bar should pull things into engagement sufficiently to do that.

Apologies if I misinterpreted ‘whacking’

MichaelG.

[Mike PooleParticipant @mikepoole82104]

As most of our drilling machines were equipped with the Barson tool it was standard practice to clean the socket and shank and then set the drill in the socket which involved feeling the tang into its slot, a light tap with the Barson bronze hammer head finished the job. The tap is very light and hammering or whacking does not come into it, if the Barson had gone walkies then I would just press the drill down on a block of wood. This method has worked for me, drills very seldom come out of the socket and ejecting with the Barson or drift is easy. At home with lighter machinery I use a double taper type lever drift to jack the drill out and this is kind to the machine and the tang. I use a very small copper faced mallet to tap the drill in if I can find it or again just press down on a piece of wood. The taper socket is a crucial part of the machines accuracy and should be kept clean and the shank of anything to be inserted should be cleaned and inspected for any damage which can be gently stoned down so it will not damage the socket. A socket and shank in good condition will happily drive the largest drill that should fit the socket, 7/8” or 22mm is about the limit for morse 2 reduced shank drills and jump up sockets should be used with caution.

Mike

[Mark Gould 1Participant @markgould1]

Thanks Mike!

[egaParticipant @ega]

Posted by Mike Poole on 08/05/2020 10:22:48:

At home with lighter machinery I use a double taper type lever drift to jack the drill out and this is kind to the machine and the tang.

My "double taper type lever drifts" are by Facom and bought from The Drill Service.

I have always fancied a Barson which seems to be a portmanteau of bastard and whoreson!

[egaParticipant @ega]

PS Brain fade! FWIW, I meant Rohm not Facom.

[SteviegtrParticipant @steviegtr]

Hi Mark. I only have a MT2 taper. So far all I do is bring the collet chuck up the spindle & finger tighten the drawbar. Then with a spanner I just nip the bar up. Between a 1/8 turn & no more than a 1/4. Have never had it slip so far. I have however had milling cutters climb out of the collet chuck. So now I tighten the collet onto the cutter very hard. My fault for mistakenly climb milling. Lesson learned with the aid of forum members.

Steve.

Edited By Steviegtr on 09/05/2020 00:51:48

[Pete.Participant @pete-2]

A few days ago I was bidding on a mt3 er32 collet chuck and collets, as the bids went up, i thought i better check it has a metric thread, so I sent the seller a msg asking this.

Below, a picture of the items i was bidding on, the sellers response to my first question, and the sellers response to my second question, which was, 'there should be a female thread inside'

The reply left me completely confused.

It has added those replies in wrong order, this website must have been designed for PC use, it's impossible to manipulate certain things from a tablet.

[Pete.Participant @pete-2]

This is the items in question.

[HopperParticipant @hopper]

He says it was used on a tool n cutter grinder. Light load so no draw bar facility. So not suitable for a mill, where drawbar is needed.

[Pete.Participant @pete-2]

What confused me was, he said it was the same as every commonly available mt collet chuck, I've never seen one for sale without a drawbar thread? I wasn't questioning his use, but the 'standard' collet chuck with no thread for a drawbar.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Pete. on 09/05/2020 01:47:16:

What confused me was, he said it was the same as every commonly available mt collet chuck, I've never seen one for sale without a drawbar thread? I wasn't questioning his use, but the 'standard' collet chuck with no thread for a drawbar.

.

Technically, I suppose it is true to say that the collet chuck is standard ER32

But the Morse Taper shank which supports it is not threaded for a drawbar.

The statement was probably perfectly clear in his mind :

The English language is sometimes difficult to use unambiguously.

MichaelG.

[John OlsenParticipant @johnolsen79199]

It is usually possible to add a tapped hole for a drawbar if needed. The commercial Morse tapers that I have done this to were surface hardened, possibly nitrided, so grinding off the end surface exposes the softer core, which can be drilled and tapped. It does tend to be tough material, but it can be done. I've also got a MT3 to MT2 adapter with a tang on it that I have managed to put a drawbar hole through. That lets me use a MT2 ER16 chuck on the milling machine.

John

[not done it yetParticipant @notdoneityet]

I’ve yet to come across a MT taper without either a tang or a thread for a drawbar. They say you learn something new every day!

If it came with no thread, I suspect it came with the collets in the yellow packages.🙂 So I wouldn’t want to rely on that chuck being to specification.🙂

[Mark Gould 1Participant @markgould1]

Thanks everyone for the info!

Mark

[Martin ConnellyParticipant @martinconnelly55370]

NDIY, these are my lathe centres, all mt2. As tailstocks are generally self ejecting they do not have tangs or threaded holes. The rotating centre was just too short to self eject so I had to drill and tap it to fix it.

Martin C

[not done it yetParticipant @notdoneityet]

Thanks, Martin,

Yes, come to think about it more carefully, the dead centres don’t have either.

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