MT4.5 Taper

[malcolm hollinsParticipant @malcolmhollins96641]

I have a Kerry Lathe with L00 Headstock.

I would like to modify a MT5 / MT3 Adapter to a MT4.5 /MT3.

I know the sizes of MT5 and Mt4.5 but not their Taper Angles.

I have watched Youtube Joe Pieczynski – "Setting the compound to precision angle" so I need the MT4.5 taper angle so that I can set up the Cross Slide.

I would like to know if I can turn the Mt5/MT3 down to the correct angle and cut off the Tang so that I would finish up with a Mt4.5 Sleeve that I could use in the L00 Headstock.

I have all the Test tools I would need for any set ups e.t.c

[malcolm hollinsParticipant @malcolmhollins96641]

What is the MT4.5 Taper in Degrees.

[EmgeeParticipant @emgee]

Malcolm

Details in this chart

**LINK**

Emgee

[John HaineParticipant @johnhaine32865]

And this might help too…

**LINK**

Some of the other bits of the site are scary! Home nuclear fusion anyone?

Edited By John Haine on 05/12/2021 10:49:04

[Ady1Participant @ady1]

I would do 1 or 2 test MT4.5s first, before cutting the adaptor up

[JasonBModerator @jasonb]

You might want to message John Patton 1 in this thread, he recently had a batch made and may have a couple left.

[EmgeeParticipant @emgee]

Malcolm

I notice there is a very small difference in the angle of the MT4.5 and MT4 in the chart I linked to but the very good article linked to by John describes the angles as equal.
So best to do as suggested by Ady, turn some angles on metal stock before cutting the adapter.

Emgee

[Clive FosterParticipant @clivefoster55965]

Malcom

You set the cross slide or, better taper turning attachment, angle by reference to the internal headstock taper using a lever type indicator running on the back side of the headstock taper. Why back side? Because the turning direction will be small end to large which is the stiffest way.

If I absolutely had to do a foreign taper I'd use the two collar method. Bad enough with a taper turning attachment and a royal pain with a top slide but its as accurate as your patience makes it. Work out the collar diameters using the gauge length along with the small and large end diameters from the specifications. Never use angles as folk like us aren't set up to make sufficiently accurate measurements. Slopes are far easier to get right. There are darn good reasons why inches per foot et al was the way things used to be done.

With only common Model Engineer – Home Workshop Guy (or Gal) it's not possible to reliably and quickly set up the angle to book values with sufficient accuracy and within tolerance. Improvised / knife'n fork methods can sometimes work but all too often end in disaster or, at best, a marginally acceptable fit. Whatever the write up, internet reference or YouTube video may say or imply.

Turning an accurate morse taper is pushing the capabilities of typical home shop lathes. Your Kerry is a step or two up from the typical Myford / Boxford / SouthBend / small import machine but it will still have a proper job on its hands. I've driven one and have a good idea of what they can do. Doesn't get to be routine until you hit proper toolroom lathes like mine.

Clive

[malcolm hollinsParticipant @malcolmhollins96641]

Thank you all for your input and suggestions.

I do not need a MT4.5 sleeve I just want to get more experience on using my lathe and finding out how to make things.

Once I make the MT4.5 I probably with never use it.

Joe Pieczynski method seems to be a excellent way to set up the cross slide to cut a taper. Its the one I will try.

If I was successful in making it what would be the best way to remove the tang?

[SillyOldDufferModerator @sillyoldduffer]

Posted by malcolm hollins on 05/12/2021 14:59:18:

…

If I was successful in making it what would be the best way to remove the tang?

The couple of tangs I removed from tapers were both hardened and saws wouldn't touch them. Turning an existing taper might hit the same problem, so test with a file first. Trouble ahead if it skates off!

The tang is easy whether hardened or not – angle-grinder!

Dave

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