Not able to help with Unimat information but most industrial fastener suppliers should supply the nut.

Bearing locknut is M12x1, if that helps.

Have you joined the Unimat SL group on Yahoo yet Charles? It is a friendly and active group and there is lots of handy stuff (including books, manuals and parts lists) in the files section. You can find it here. As far as spares are concerned, you can get everything at Toms Tool Store, although to be honest I haven't used them myself as I'm too tight to pay shipping from the US.

Brian

My admittedly limited experience with a Unimat SL taught me that one of the most important things was to use really sharp HSS tools. I never tried carbide but my subsequent experience would suggest it is not really rigid or powerful enough to make good use of them, although someone will probably come along who uses them all the time.

It was a sweet little lathe and I still have some regrets about selling mine a few years ago but it was far too small for some of the jobs I wanted to do.

That's false economy. Small lathes, and the inexperienced, need all the help they can get. Using cheap cutting tools often just leads to frustration. As does the use of scrap material of unknown composition. It's not uncommon for threads to appear on the forum along the lines of difficulties with cutting and getting a good finish. Many of the probems are solved by changing to known material and quality cutting tools.

Andrew

+1 for what Andrew says about known material and sharp tools.

Lot to be said for splashing out on some delrin, which cuts easily and is very well behaved, and proper free cutting mild steel to start with. I've had a few bits of material that were far harder to cut than they should have been despite being ordered under a proper type number from reputable suppliers.

For sharp tooling I'd not worry too much about "book" profiles and angles. These are fundamentally for larger machines taking heavier cuts in industrial practice. You will, initially at least, be working with cuts of less than 50 thou / 1 mm so the actual dimensional difference between book profiles and "really easy to keep sharp" will be minimal.

Hollow ground profiles are much easier to keep sharp than flat ones but they are fundamentally weaker and don't stand up to industrial loads. Which matters not at all to a Unimat user.

I'd obtain a half decent 6" or, better, 8" bench grinder and set the toolrest level with or just above wheel centre line. Generally anything above the stupidly cheap machines do a very acceptable job of actually grinding. Weak points are toolrests, invariably flimsy and hard to set just so, and wheel dressing. Can be coped with initially and fixed at leisure.

Make your basic tool from a piece of square HSS of appropriate size. Grind about 3/8 – 1/2" of the long, leading edge side, on the periphery of the wheel taking just enough off to give a hollow grind and sharp edge on top. Keep the grind parallel to the body. Now do the same on the front end of the tool with the edge leaning back about 10 or 15° to give clearance. Finish off by swinging it round to give a small radius on the sharp tip. A mm or so should do. Make another the opposite hand so one cuts moving along the bed and the other cuts going across. I say job done. Other folk say put a similar hollow on the top which does give a better shape but whether it makes any real difference at sub mm cuts I doubt.

If you have a slipstone or diamond hone rubbing it across the tool will make it even sharper. The hollow grind supports the slip or hone at the to and bottom so its easy to keep it properly aligned. With a flat grind its very easy to rock the slip or hone leaving a nice polish but taking off the very sharp edge you are trying to achieve. Only takes a few bad strokes to spoil things. Needs a microscope to see the damage so you will never notice the error. Just be monumentally frustrated wondering why your newly sharpened tool isn't cutting like it ought to.

After the first sharpen and hone work on the front edge and point radius only. Unlikely to need proper re-sharpening until you have honed a flat 1/2 a mm to a mm below the cutting edge.

There are a lot of ways of producing a good cutting tool. Most folk have their preferences and have sorted methods which work for them with the equipment they have and suit the jobs they do. Plenty to investigate once you get the hang of things. For beginners easy to make, easy to keep sharp and works pretty well will do.

Clive

Edited By Clive Foster on 27/09/2019 12:19:57

Your cheap holders will likely do for now but worth getting a few decent inserts and for aluminium, plastics and other non ferrous I would suggest the ones made for aluminium which will have a code **GT depending on the shape of insert you have chosen.