Unimat toolpost

I have some unimat parts I'm converting back into a usable lathe. Could some kind soul who has one measure the height of the bottom of the tool slot to the top of the carriage for me please? I'll have to make the tool post.

Dug out my old unimat from the pile in the corner and got 5.81 to 5.85 on my digital caliper as far the thickness of the bottom of the toolpost is concerned

Edited By Ady1 on 26/02/2015 01:12:41

Is that a Unimat SL or a Unimat 3 ???

John

I get 16.9mm on a U3 fixed single tool post, that suits the 6mm toolbits with a small packer.

Mine is an SL

While we are on the subject of toolposts for Unimats, a few years back I had an article in ME describing a three way toolpost for the U3. Quite handy for repetition work, and gets in the way less than a fourway. I made one of those for it first, to a design by Gerald Wingrove, (the model car guy) but found it cumbersome. I guess the same thing could be done for the SL too.

John

There are a number of factors you might want to consider.

Firstly what size tools/toolbits do you want to use. I eventually settled on 6mm/1/4" and 4mm square bits normally using a 3 or 4 inch length cut in two. For most work the 4 mm was adequate and minimised griinding.

Secondly you will want to reduce the amount of packing required. A solution here is too make a two way tool post, like the one in the photo above* but with two slots. you might combine 6 mm and 1/4" or 6mm or !/4" with 4 mm. etc.

Thirdly I would determine the centre height by direct measurement over the cross slide top, You will need a centre or similar to fit the head stock bore. preferably with a measureable diameter and then do the maths for each tool bit size.

Another trick would be to use a three or four way post with the registers cut stepwise.

* was a standard item find a catalogue on line to see arrangement.

Hope this helps

John

Thanks for the replies. Mine just says it's a Selecta Unimat, but definitely old style. Actually I'm thinking of making a quick change design but wanted the basic dimensions as a starting point.

john.

The old style will be the one with the round bar bed, quite a good structure for a small lathe. The newer one has a more conventional bed. The reason I asked which you which your one is was because I knew they had a different height, although at the moment I don't have access to mine to measure it. (Mine is a Unimat 3.) Either is a good little lathe, and quite versatile if you have some of the accessories. Some of which are not too hard to make if you don't have them....I have found the simple direct dividing head very handy, and that would not be too hard to make provided you could find someone to drill the division plates. It is still useful even though I have a bigger machine with both rotary table and conventional dividing head.

The little saw has been handy too, when small sections are needed.

We will continue to pretend that there is no such thing as a plastic abomination called a Unimat 1.....

John

Edited By John Olsen on 01/03/2015 08:41:47

Hi John, thanks, it sounds like 6 mm nominal is the thickness for the old style from Ady's reply. I have a cnc lathe and 2 mills, one being cnc, but sometimes it's nice just to have a simple lathe for small quick jobs!