AVM MAS 140 lathe

I'm looking for a lathe and I found this model close to me. It is an Italian lathe with 750mm distance between centers. Anybody had any experience with this model?

Lathes.co.uk sell manuals for the MAS140 - contact Tony Griffiths there. It looks a very capable machine.

It appears to have a separate feed shaft separate from the leadscrew, which is a sign of a better quality machine, not a budget special.

A very good quality machine, which appears to have a bed casting with three vee way guides that uses two vee ways to guide the saddle, as opposed to the more commonly used single vee and a flat guideway for the saddle found on many other vee bed lathes.

Just check out that you can cut both metric and imperial threads (If that is what you need) - probably by use of a conversion gear wheel set and that it is present with the lathe. (may be difficult to source after purchase).

Also a 4 jaw chuck and faceplate as minimum tooling.

Bob

It has also the gear wheel for imperial threads. Maybe tomorrow I'll go to see it. I'm still discussing with the seller about the price. Is a little over my budget since I was planning to buy something in the SIEG SC4 or SC6 range.

If you can flex your budget you won't regret it, substantially more capable than a Sieg (no offense to Sieg users, but that thing is really well designed and built).

I take it you have access to three-phase power, or the machine is single phase?

Looks like a geared head version of the Taiwanese lathes such a Warco BH600 or Chester Craftsman. An up market machine.

Having a power feed shaft will save wear on the Leadscrew, and probably provide power cross feed, as well as a greater range of threads and feeds.

It ought to be a good buy that will do what you want for years to come..

Notice that it has a QCTP, so make sure that you get all the holders as well. You might have difficulty getting extras, unless you can be certain of the marque.

4 jaw in the pic, so presumably a 3 jaw in the cupboards?

Howard

The machine is three-phase but the seller installed a converter. The chuck has 3 jaws, in that the picture was difficult to see. It has also a new DRO installed. But I want to buy it without. I think I can live without it. It just add to the total price.

That looks like a well cared for machine. I think you would be foolish to pass it up for the sake of some unit you dont need or want, right now. In a few years time, things could change and anyway, you could always sell on what you dont need. In your place, I would grab it.

Looks like a very decent lathe BUT condition is everything with machines! Give it a good inspection and run it up through the gears to see if it has any nasty noises, give the slides a good inspection and ask him to cut some steel.

Tony

Yes, I'm going to measure with a comparator the concentricity error and all slides. It didn't occur to me to cut some steel. I have this steel bar. How could I stress this lathe with it? What would be the maximum depth at which it should cut? And at what speed?

Whatever you do do not disregard the dro they Arte a great confidence booster and a great aid to repeatable parts.

How much would cost a DRO like that? I have no idea

To check the lathe, you are better to yake a very blight cut over the full, length, and compare the readings nat each end. This should tell you if the bed is teisted.

This is effectively "Rollie's Dad's Mathod" as detailed by Ian Bradly in "The Amateur's Workshop" and the "Myford Series 7 Manual". These also tell, how to shim, or adjust the Tailstock end of the bed to eliminate the twist that will result a taper over a long turned length.

Howard

I just saw the lathe this evening. I'm not sure if I've mentioned it before, but this is the first time I've seen a lathe in reality. I think that I spent an hour but I have the feeling that there were a lot of details that I missed or I was completely unaware of. And I have even more questions now ... but here are my remarks so far:

- I put a 6mm mill in the chuck and I measured the concentricity error at 10mm from the jaws. The maximum deviation was 0.1mm (0.0039"

- I fixed a comparator on the compound and put the tip on the bed. Then I set a low speed for the carriage and move it across the whole length. Maximum error was 0.04mm (0.00157"

- I tried to lift the carriage using moderate force and the comparator didn't moved a micron.

- We cut my steel rod from above. First with a 0.1mm cut. The surface was very smooth. Then we cut 1mm deep using a carbide tool. There was a sharp strong noise a lot of smoke from burned oil. It was not something that I would like to replicate. The bar was almost to hot to touch after. The surface also looks nice. Now I realized that I should use a much longer bar. Actually the seller had one prepared but I didn't realized it's purpose. The highest difference in diameter for the 1mm cut is 0.01mm(0.00039"

- I opened the gear box. There was clean oil at the bottom and the edge of the wheels feels sharp. There was no suspicious noise in any gear setting. Both longitudinal and transversal automatic feed is working

- all the slides run smooth and apparently there is no backslash.

- In order to change the speed sometimes you have to manually rotate the chuck. But I suppose this is normal, the wheels are not always aligned.

- The tailstock can be adjusted only horizontally

I think I will return to cut a half a meter bar. I used this comparator.

How do you think are the measurements so far?
If I cut a long bar what is the maximum expected error for a lathe in good condition?

Edited By Sonic Escape on 13/02/2023 19:48:12

Edited By Sonic Escape on 13/02/2023 19:50:55

Edited By Sonic Escape on 13/02/2023 19:55:23

Those numbers sound pretty good to me. Cutting a longer bar may well show up some taper but that's also a function of how well set up the lathe is, there could be some bed twist which could be removed by levelling. Also do you expect to support the bar at the end away from the chuck? Lots of ways you could get apparent errors due to the process not the machine.

Those numbers sound pretty good to me. Cutting a longer bar may well show up some taper but that's also a function of how well set up the lathe is, there could be some bed twist which could be removed by levelling. Also do you expect to support the bar at the end away from the chuck? Lots of ways you could get apparent errors due to the process not the machine.

The tests as you describe them are not telling you anything much about the lathe. Runout of a 6mm milling cutter held in the chuck is maybe telling you the chuck has about the normal acceptable runout for a three jaw chuck, or that the milling cutter is not perfectly straight, or that it was not gripped very well in the chuck. Plus, the condition of the chuck is not the condition of the lathe.

The other test of a dial indicator on the compound slide bearing on the bed as you traverse the carriage is telling you nothing. The carriage will follow the bed regardless.

Your metal cutting test sounds about right. You will get heat, and smoke if there is oil there, when taking a 1mm cut with carbide. Taper on a roughing cut like that means nothing.

There is nothing to be gained by trying to turn a longer half-metre piece of bar. The taper on it depends entirely on the tailstsock, which is fully adjustable. Turning test for taper without a tailstock centre is usually done with a piece of steel 25mm diameter and sticking out of the chuck by 100mm. Any longer and you get too much flex in the workpiece.

Once you get the lathe into your workshop, you can set it up with shims under the mounting "feet" to make it turn parallel without a tailstock centre, and then you can adjust the tailstock so it turns parallel with a tailstock centre in place.

It looks like a good quality machine, so if it is not making bad noises and if it is turning nicely like in your picture, I would buy it.

Edited By Hopper on 14/02/2023 02:59:13

Now I'm even more confused about what means a good quality lathe. But for some reason I'm starting to think it's a good idea to buy it. I'm going again this afternoon to see it. I have another steel bar left.

Somebody reverse engineered a 3D model of this lathe: **LINK**