To be honest unless you really want to turn a m0 taper just buy a blank end M 0 taper,only a few pound.

Hi Pete,
If you have a finger type DTI then you could try this method. Mount the chuck that you want to make the taper for in you lathe chuck with the taper out. Make sure the taper in the chuck is running true. Set the top slide to be about the correct angle. Wind the cross slide to position the DTI finger on the back of the taper. Now wind the top slide in and out to follow the taper. Use the way the reading changes to adjust the top slide angle in the correct direction. Repeat this until the DTI does not change its reading as the top slide moves the finger along the taper. When I did this I mounted a piece of angle on the cross slide with a screw at each end to push on the top slide so that fine adjustments could be made. I think I have some pictures of the setup somewhere. Let me know if you would like to see them.

Les.

Hi Peter,
I did not realise a #0 Jacobs taper was so small. When I did mine I used a variation of what I suggested as the taper on the chuck was pitted due to rust which caused the DTI to jump around.. What I did was to turn a piece of wood to a diameter of about half way down the taper. I then milled a groove down one side of the wooden dowel I had made so that I could use it to press a piece rod against the taper. Having the pressure applied half way down the taper ensured that the rod was in full contact with the taper. As the rod might flex with the pressure of a DTI I used an electrical contact probe (Just an piece of rod insulated from the toolpost and a battery LED and resistor.) in conjunction with the DRO on the cross slide to take measurements.

This is the setup I used.

This is the wooden plug.

This is the fine angle adjustment jig.

If you do use this method you need to ensure the rod is horizontal. (Support the far end.)

Les.

The technique found by Jon Gibbs is the correct way to accurately produce a known short taper. You run the compound slide along the hypotenuse and check the rise at the end.

However you do not need a setting bar between centres and in fact this can introduce errors. In a good chuck or soft jaws a long cutter, silver steel or dowel pin will do.

Also you can reverse the process and eliminate any need for a parallel.
Put the clock in the chuck and a button or small bearing in the toolpost. Then rock the saddle so the clock finds the peak whilst at the bottom and top of the hypotenuse. The difference must agree with the calculated rise.

It was an apprentice piece for me to make mating tapers that "locked" like a morse taper. A taper fit with less than 5 degrees included will lock if the finish is good. Our test piece had to carry two kilos by fit alone

A toolmaker's lathe with a vernier taper turning attachment was nice too.

ring up Mr Arrand, who makes loads of taper tooling, he will probably make you one. Won't be cheap, but will be top class. 01664 454566