cutting morse taper

[trevor jones 1Participant @trevorjones1]

I have been looking at makeing a morse taper MT2. On the internet theres lots of info but what size diameter round bar do i start off with and are there any tip that you all mite have.

 thanks

Trevor.

[trevor jones 1Participant @trevorjones1]

[John HaineParticipant @johnhaine32865]

3/4 inch, 19 mm minimum.  I have used the top-slide set-over method, works fine but you have to take great care setting it to a reference taper.  Definitely need support from the tailstock.  It’s awkward avoiding the t/slide fouling the t/stock on the Myford, best use one of the long tool-holders to create maximum space.  Good luck!

[Rob ManleyParticipant @robmanley79788]

Whatever happens, unless you have a taper turning attatchment and its well made, you will not get a perfect taper.  Once the taper has been cut, take a good 2MT adapter and blue up your taper.  Find the high spots and rub gently with a needle file whilst rotating, repeat, repeat and repeat until you have no high spots.  Just make sure that you clean the adapter and taper every time you try it.   I have made many 2MT splindles for die holders etc, and have never had one come loose using this method. 

R.

[NJHParticipant @njh]

Hi Trevor

The above replies are good but the question is why are you turning a MT2 taper? If it’s for the experience of making it fine but if it’s part of some project you may be able to save some time. Blank end arbors are available very cheaply and the soft ends are easily machined to incorporate into a project. ARC sell them for as little as £2.75 see here :-

http://www.arceurotrade.co.uk/Catalogue/Blank-End-Arbors

Good luck either way !

NJH

Edited By NJH on 15/03/2010 17:17:01

[Ian S CParticipant @iansc]

NJH you might have cheap tooling like that in your part of the world, but not everyone lives in a place where these thing are available. As model engineers we should encourage people who are prepared to DIY rather than BUY, For all I know Trevor lives next door to a supplier. I’v done 3MT on my lathe (it’s a 1324BH Taiwanese one), and had to take 2 goes at the taper because of insuficient travel on the top-slide, but it worked ok, just make sure that the tool is spot on center hight. The way I set up the angle was to put a center between centers and with a DTI in the tool post adjust that untill it traverses the length of the taper on zero. For some reason all the different MTs are a different angle, there must be a reason but it beats me why. Ian S C

[chris stephensParticipant @chrisstephens63393]

Hi Guys,

Some years ago MEW did an article on making a Morse taper using the “Skiving” technique. Sorry, can’t remember which issue but someone with an index might be able to find it. 

chriStephens 

[Peter G. ShawParticipant @peterg-shaw75338]

Hi,

My homemade database throws up MEW27 page 51 (Jan 95) for “Skiving” as a different method of lathe cutting. It also says that whilst it apparently has certain advantages, I don’t understand it!

 

Peter G. Shaw

[Ian S CParticipant @iansc]

I think in this method a tool similar to a wide parting tool is used. This toolis lined up square to the work and rotated(easy if made of round stock)about 45deg in direction of travel, result no tool marks. Hope you can understand that or maybe someone else can do better. Ian S C

[chris stephensParticipant @chrisstephens63393]

Hi Peter,

Even I  had to read the article a few times for it to make sense.  but it does in the end.

 

Perhaps it is time our esteemed Editor commissioned a new article on the subject? Provided he can find an advocate, of course.

chriStephens 

[David Clark 13Participant @davidclark13]

Hi There

A skiving tool is as far as I am aware is a tool applied at a tangent to a job and

also supports the work as it cuts it away.

regards David

 

[Ian S CParticipant @iansc]

The tool I was trying to discibe is apparantly in L.C.Masons book “Usinig The Small Lathe”, its used for the finnishing cuts, just a few thou at a time, very similar to a chisel on a wood lathe (gave up wood turning when I became alergic to wood dust). Dave I think the tool that supports the work is the one for running thin bar down to thinner bar, it couldn’t work on a taper. Ian S C

[CirclipParticipant @circlip]

Shame on you DC1, it was described in ME with various pikkys within the last 15 years.

 

  Edit, Sorry, breaking my gob in for a fool AGAIN, Peter got the article, that’s the one I remember.

Edited By Circlip on 16/03/2010 14:38:14

[Peter G. ShawParticipant @peterg-shaw75338]

Len Mason, on page 41 shows a variety of fine turning tools: Goose neck, Swan neck or Spring; and one he calls a “knife tool”. I think that was because he didn’t know what else to call it. This tool is, I suppose something like  a parting off tool, but much, much broader, in that it has a straight front cutting edge with a parallel groove behind it. In use the tool is applied to the rod with the cutting edge at, say, 45°, so no need to bother about centre height, and the swarf comes off “like cobwebs leaving a smooth, satin-like finish”.

My description is only approximate. Suggest you read the book to find out more.

 

In the same chapter, Mason also describes a tailstock turning tool which is designed to turn down and finish turn a rod to a particular size. Again refer to the book for more details.

 

Regards,

Peter G. Shaw 

[David Clark 13Participant @davidclark13]

Hi Circlip.

Yes it could.

Don’t have time

to find photo.

regards David

 

[Nigel McBurney 1Participant @nigelmcburney1]

hi  Set up a good master taper in the lathe,set the topslide to angle of the taper,then mount dial gauge in tool holder making certain that the gauge is exactly at centre height,then fine tune the topslide setting until the dial gauge reads zero when clocked against the master taper,For a lot of work the taper need only be the length of the top slide travel,I am thinking My ford and 2mt,  on some very small lathes the travel may be too short. turn the taper and try it in a morse socket,if it does not fit then adjust the topslide by releasing the screws a small amount so that they have some grip on the slide and tap the top slide with the handle end of a old plastic handled screwdriver,its more gentle than a plastic mallet,and keep trying and adjusting until you get it right,then cut the taper you require plus a few spares as they will always be useful,also it is a good idea to drill and tap the end of the taper for a drawbar.

[trevor jones 1Participant @trevorjones1]

ok i had a go at makeing MT2 but in the end i think i will buy from arceurotrade thanks for all your help.

and Ian thanks for your encouragement

Trevor.

[mgjParticipant @mgj]

I’m afraid I disagree Nigel.

 

That is a way often advocated, but unfortunately it suffers from a great disadvantage. You set up with a DTI, and you cut with a cutting tool, so there is a difference in the magnitude of the forces(and direction of course too).And the problem with any taper is that unless it is an exact fit, it will only touch at one point, which means it won’t grip and it will wobble, which isn’t usually the idea..

 

Its OK if you can use blue and a socket and are prepared to adjust your setting, (by how much exactly?) So you end up up fiddling around all afternoon to produce an an unbrilliant result. (Fine for a non critical thing like a die guide).

 

The only real solution is to set up on a taper attachment, work it out by calculation and then adjust using a mike over distance, and using the 40tpi screw on the taper turning attachment and a DTI (not a clock), because one will be adjusting angle by literally by tenths of a thou.(moving the guide rail)

 

Did it once, turned out a batch.!!!

 

Now I just buy them, and cheap at the price

 

The smooth surface is no great problem – carbide tip, nose radius of .8mmn and the thing will come out looking like it was cut from FC aluminium.

[CirclipParticipant @circlip]

Rabbited before, weapons of choice are a tailstock centre (center) offsetting tool fitted with ball ended centres (centers).

 

  One thing nobody else has mentioned, Is it neccessary in the O/P’s design to have a full length face?? An inch (25mm) at either end with a relieved bit in between would still be accurate, providing the angle settings were correct.

 

  Regards  Ian

[mgjParticipant @mgj]

Ian, I agree with you.

 

Yes it can be done, but its a lot more difficult to get a really good fit than is often suggested, and running a clock down a mounted version is not the best way of doing it..

 

From my point of view, whether it is actually worth doing depends on the application, bearing in mind that for a critical application full line contact under load is essential Otherwise its a point contact and a wiggle. (Once you have the angle right, relieving the centre belt is  a neutral effect.)

 

Actually I don’t think you CAN (or should) do it (properly)using a female and blue? Something in my mind is telling me that there is an difference on taper to allow for deformation under load, and that is what provides (part of?) the locking effect.  Not sure about that, but I think so.

 

[Michael Cox 1Participant @michaelcox1]

I have a technique that I use to cut morse tapers that gives satisfactory results. But in order to use it it is necessary to have a means of reproducibly changing the top slide angle. On my lathe I bolt a small piece of bar to the cross slide with an M3 screw that just touches the top slide. By loosening the top slide and then adjusting the screw the top slide angle can be easily altered by very small amounts. The technique is the roughly set the top slide at the right angle and then start cutting the taper. After a couple of passes test the taper with a femal taper to see if it rocks. Whilst doing this examine the junction of the taper and the female taper. If the piece has insufficient taper it will move at the mouth of the female taper. In this case increase the taper by adjusting the top slide using the screw. If the there is too much taper then there will be no side to side motion at the mouth of the female taper only a rocking motion. In this case then reduce the angle of the cross slide. After another cut test again and adjust the top slide as necessary. Within a very short number of iterations it is easy to obtain a perfect fit. For final fitting blueing can be done but usually this only confirms that the fit is perfect.

Mike

[mgjParticipant @mgj]

Well perfect is a very dangerous word in engineering.

 

In this case one only needs an error which is inside the thickness of the blue to guarantee a point contact, and which is not detectable.

 

The result will be something which is more prone to shaking loose under intermittent loads etc, or will permit runout under load. (Or worse will jam if made from soft material) As before, it all depends on the application. If its not critical – fine. Or if you use a drawbar with it, then a very small error be ok.

 

Still I’m glad that someone can get it perfect.

 

 My method is as follows.

 

I do the maths for the taper (2 or3 morse), and that converts the solid angle in degrees into a deflection in thou. I’m using a base leg of 5″”. That’s 1/2 the length of the taper turning attachment guide, so I have a 2:1 advantage in sensitivity give or take. The taper attachment has a 40 tpi micrometer setting screw – like your M3 screw. When I have it close, I then measure my setting along the length of the attachment guide (10″), not with a clock, but with a DTI graduated in tenths of a thou, so you can read to a couple of hundredths over 10″. That is a microscopic error?

 

Then its cut with a new .8mm radius tip, under power feed, which you can do with a a taper tuning attachment.

 

Even like that, its still not perfect, and still not as good as el cheapo bought item. 

 

So for the hassle involved in not getting it right, IMO,  its easier to send off to Chronos/ Axminster/Warco etc 

 

 

 

 

 

Edited By mgj on 23/03/2010 13:43:07

Edited By mgj on 23/03/2010 13:45:07

[Ian S CParticipant @iansc]

When I make MTs I use blue on the taper in a sleeve until I think its fairly near, then I mark the taper with two or three pencil lines length wise along the taper, put it in the socket and twist slightly and remove, if the pencil lines are removed thats it, works for me. Ian S C

[chris stephensParticipant @chrisstephens63393]

Hi Guys,

Time for the philosopher to wade in on the subject.

 

Why the hell would you make your own Morse tapers when you can buy them for a few Quid? The time and trouble involved does not make the exercise worthwhile, except as a training one. As a training exercise, though, there are many valuable lessons that can  be learnt.

Let us look at what can be learnt, first there is the need for getting a very fine finish on our work. If you turn a near enough taper and leave a rough old surface, you might well get a taper that fits tightly, but once the high spots have worn a bit  you will get slop and a wobble, V.bad. So, we will have to learn to get a good finish, we will also learn how to use something like a “Sharpie” not only to test the taper but also as a way of checking our finish. Amazing how a smooth looking finish can be shewn to be rough, by use of a marking pen.

The second thing we will learn is just how critical very small adjustments in angles have on tapers and their fit. When using a top slide to cut tapers, the merest hint of adjustment can radically alter the fit , so we have to learn patience when doing our set-ups and the need for precision, not only as a principle but also in wielding our “tapometer” of choice, to alter the angle. We also learn that the diameter  of a taper has a pronounced effect on how far the male part will fit in the female, but surely most of have learnt that long ago  but it is worth learning again in this context.

A third thing we might learn is that a DTI mounted horizontally and on centre height in the tool post, is much more useful for set ups than any one mounted vertically on a Mag. stand. This lesson will prove immensely useful when we learn to use a Four jaw properly.

 I’m sure others more experienced than I can think of more lessons that can be learnt from this apparently simple exercise, maybe a lesson on hardening and tempering or tool post grinding, but that’s all from me except to say, if you haven’t tried before, do make a few Morse tapers, but if you want one for a tool you are making spend a few quid on a ready-made, and remember that even a hobbyist’s time has a value.

 chriStephens

[Ian S CParticipant @iansc]

Some times I can get tapers, but usually have to make them, a couple that I bought had inaccurate tapers(hardened), and I had to grind them. Made in England. Ian S C

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