Good 'Hobby Quality' Metal Lathes

[Waldemar]

 

Nowadays, I use almost exclusively the larger Proxxon PD 360 lathe for all my needs, so my Unimat 3 is practically unused, but some time ago I decided to modify the hopeless original power transmission to toothed belts. Simply put, the frequent replacement of broken V-belts (actually round in cross-section), and also their tendency to slipping, became too annoying over time.

 

The attached video shows a prototype drive system made to verify in practice the assembly and operation of the replacement kit, and the attached photo shows most of the components from a few sets that I made with a view to selling them to other Unimat 3 users. All components are already fully machined and with tolerances within 0.03 mm for important dimensions. The replacement set maintains the same rotational speeds as the original.

 

I also thought about replacing the motor with a more powerful one, but this could be too much of a strain on the rather delicate Unimat 3 and could lead to rapid damage of the lathe that would be difficult to repair or costly.

 

 

 

 

 

 

[wefalck]

One should also keep in mind that these round belts running in a V-groove provide an important safety feature, when working with one's nose close to small workpieces: if something hooks, the belt acts as an overload-clutch by slipping.

[Waldemar]

 

16 minutes ago, wefalck said:

One should also keep in mind that these round belts running in a V-groove provide an important safety feature, when working with one's nose close to small workpieces: if something hooks, the belt acts as an overload-clutch by slipping.

 

Yes, I am aware of that, but the advantages of the replacement drive transmission definitely outweighed this potential inconvenience. One simply has to make a choice, and this is usually the choice made by many or even most manufacturers of other lathes. Personally, I guess that in the case of the Unimat 3 manufacturer, it was not about a “safety feature” at all, but about simplifying the design and the selling price. When I showed the Austrian manufacturer of Unimat 3 my drive solution for its lathe, they asked me to send them one set for evaluation.

 

 

 

Edited Wednesday at 11:18 AM by Waldemar

[Y.T.]

5 hours ago, wefalck said:

You may be able to find ES-collet adapters with this thread.

 

5 hours ago, wefalck said:

A useful set of say ES16- collets can be had for little money these days.

Do you mean ER collets?

[wefalck]

Sorry, yes. There are also ES-type collets, but they are not very common.

 

[tmj]

On 12/10/2025 at 2:01 AM, wefalck said:

I don't remember what the spindle-thread is on the SL, I think 12 mm x 1 mm or 14 mm x 1 mm. You may be able to find ES-collet adapters with this thread. Or someone may be able to turn it up for you. A useful set of say ES16- collets can be had for little money these days. This so much safer for working on small parts, than working close to fast rotating jaws on a chuck ... 

The SL is indeed 12 X 1. As for getting too close to the chuck, I have split shaft collars to deal with that. If needing to get dangerously close, I'll simply move my cutter to within a few thousands of the jaws and lock the shaft collar to the way, up against the cross-cut slide. It might 'look' scary while turning up to the chuck, but it will be impossible for my tool to actually go too far, where nobody truly wants their tool to ever go! Hmm. Maybe I should rephrase that! LOL 🫤

[tmj]

As for belts... that's the least of my concerns. I'm used to running machines with gears that will 'never slip' if you make a mistake! 😮 

Besides. It's also good to 'crash a tool' now and then. It keeps you on your toes and really gets the ol' heart a pumping, which is very good for cardiovascular health! 😁

 

Edited yesterday at 12:27 AM by tmj

[kgstakes]

Maybe a little late here but I own a taig lathe and am very happy with the results I get with it.

 

 I’ve turned metal and wood on it and works well for both.

 

 The smallest I’ve turned - see picture below

 

 

 

chair I turned all on taig lathe and it’s 1/12 th scale.

 

Edited yesterday at 04:42 AM by kgstakes

[Toolmaker]

7 hours ago, tmj said:

It's also good to 'crash a tool' now and then. It keeps you on your toes and really gets the ol' heart a pumping,

That made me chuckle.

Many years ago a colleague got his “S” and “Z” mixed up and sent the turret into the headstock on a fairly large (and expensive) cnc lathe at 3 metres per minute feed rate. The complete 10 station turret detaching and dropping onto the swarf conveyor had us all on our toes. 

[ChrisLBren]

Wow KG - tremendous work !  I am thinking about buying a TAIG lathe.  I love my TAIG mill and want to add their lathe to my collection.  

 

This will be my first lathe - which lathe did you buy and what accessories ?  I will need it for cannon, capstans and for other small parts for my La Renommee build.

 

Thanks,

Chris

[kgstakes]

4 hours ago, ChrisLBren said:

Wow KG - tremendous work !  I am thinking about buying a TAIG lathe.  I love my TAIG mill and want to add their lathe to my collection.  

 

This will be my first lathe - which lathe did you buy and what accessories ?  I will need it for cannon, capstans and for other small parts for my La Renommee build.

 

Thanks,

Chris

Taig lathe - I got the factory assembled with power feed and then bought most of the accessories for it.

 

 

then I also bought tool post for wood turning and a few other accessories.

 

 One thing I still need to get is a 4 jaw chuck and I’ll buy that from sherline (only because of the smaller size they offer).

 

 What mill to you buy from taig? 

Edited 14 hours ago by kgstakes

[ChrisLBren]

I bought the 2019 ER.  It has the more powerful motor and longer bed

[Toolmaker]

15 hours ago, kgstakes said:

The smallest I’ve turned - see picture below

That is some fab work you are doing. Very impressive.

If you haven’t tried this you might want to give it a go if you need very small turned diameters. It’s an old machinist’s method where you start with a larger sturdier diameter, one that won’t noticeably flex when you make the cut. I can’t vouch for wood as I never machined it professionally but I could take a .500 brass bar and machine a .020 diameter by 1 inch long. The tooling has to be geometrically correct, and of course it has to be on centre. You also have to hit the required finished diameter on the first cut as you certainly cannot take a second cut. I suspect with wood, you would need to take the grain into account.

[wefalck]

I have made myself adjustable stops for the slides. Once you hit the desired diameter on a short length, you set the stop and then cut to the stop in subsequent steps.

 

On my watchmakers lathe I can machine 0.3 mm diameter belaying pins from steel. Most brass I have access to is too soft for this. Shorter pieces I can machine down to 0.1 mm diameter and my collets go down to 0.2 mm. However, mass-fabrication of such parts is difficult and nerve-wrecking ...

[tmj]

9 minutes ago, wefalck said:

On my watchmakers lathe I can machine 0.3 mm diameter belaying pins from steel. Most brass I have access to is too soft for this.

Have you tried 'hammering' your soft brass to work-harden it prior to turning? I do this with both copper and brass prior to machining. It works quite well. If you need to soften it up again, just heat it with a torch. 

I've never tried turning anything as small as .3mm. That's 'tiny! 

[wefalck]

In fact, for such tiny parts in brass, I use nails as stock. The stamping process noticeable hardende the brass.

 

I know, many modellers are afraid of steel and some frown upon it because it may rust, but early on in my 'career' as self-taught turner, I discovered that I liked working with steel. It depends, of course, on what kind of steel you can find, some steels are very easy to turn and others are a real pain. 

[tmj]

28 minutes ago, wefalck said:

some steels are very easy to turn and others are a real pain

This is quite true, however. Proper grinding/sharpening procedures of the tooling can typically level the playing field with all alloys. This is something that a body needs to learn how to do, manually, via trial and error. 'Off the shelf', mass produced HSS and Carbide cutters/tooling are merely a generalization of a wide range of 'typical' reliefs and standards. They're great, for the most part, however. If a tool is not cutting as well as you'd like, it is typically due to the grind of the tool along with improper feeds and speeds. I learned on steel(s), however. When I started messing with other alloys (brass comes to mind) things didn't work right, anymore. I was following the 'Machinery's Handbook' for Feeds and Speeds but not liking the results at all. I was befuddled, until an old-timer told me just how important the actual grind 'geometry' of the tooling was. One size, per se, does 'not' fit all. You can do everything right, but if your tool isn't properly shaped for the specific material you are cutting, you'll 'never' be satisfied with the finished results! Mass-produced, quick-change carbide cutters are fantastic for general work. I use them religiously! I also keep a good supply of HSS blanks on hand, at work, for those curious times when things just don't want to go right. I'll then break out a HSS blank, grind a little and turn a little... yadda, yadda, yadda on setup material. Once a good grind produces nice chips/shavings at a given feed/speed... it's time to get back to work and start making money again! 😏 You'll never find any traditional references to my custom grinds, as there are none. It's truly 100% trial and error via asking the metal 'and' your machine what it is that 'they' actually want via the current project at hand! Every project has the potential to be quite different! You need to be willing to adapt.