New Mystery Lathe

[mart7mcfl7Participant @mart7mcfl7]

A chap had this for sale last night on a well known marketplace, Initially I thought it was a flexispeed and the plate was too worn to identify anything.

Seems some kind chap scratched something on the name plate for future reference.

This is very much a project lathe and I intend to give it a decent amount of tlc during the winter evenings, coming from a Unimat 3 I think this maybe a step up in terms of cutting performance.

All in I paid around £90 pounds for it

If anyone would be kind enough for some thoughts or advice it would be appreciated.

[peak4Participant @peak4]

Bigger than a Flexspeed I think, and as far as I can see slightly different to anything on Tony’s page for Portass
https://www.lathes.co.uk/portass/

Your front bearing cap seems to square for any of his photos.

Check the 1st paragraph of the Model S which refers to a 3″ x18″
https://www.lathes.co.uk/portass-s/

Bill

[peak4]

On peak4 Said:

Bigger than a Flexspeed I think, and as far as I can see slightly different to anything on Tony’s page for Portass
https://www.lathes.co.uk/portass/

Your front bearing cap seems to square for any of his photos.

Check the 1st paragraph of the Model S which refers to a 3″ x18″
https://www.lathes.co.uk/portass-s/

Bill

Yes, it was one of those situations, it looked a lot smaller on the photo. I questioned myself at the time if I should buy it but came to the conclusion I’d be very lucky to come across such a machine for the money spent.

The motor supplied is apparently well known, a Brooks Gryphon, 1400rpm and 1 horse. its a bit of a heavy old girl. To save space I might let the motor go and use a more modern equivalent but we will have to see.

Thanks for the info, I’ll be sure to take a gander after dinner.

[bernard towersParticipant @bernardtowers37738]

I should think the 1 hp motor is enough to tip it over!!!

[Dave HalfordParticipant @davehalford22513]

It’s just possible that brass plate has been turned round. I can’t think of a reason to fit a blank one.

[peak4Participant @peak4]

This photo off Tony’s site looks to have the same squared off bearing caps, as well as a similar lead screw handle.
The clutch lever, being cast, may have been replaced if broken; the grease/oil nipple on it is also similar.

Bill

[bernard towers]

On bernard towers Said:

I should think the 1 hp motor is enough to tip it over!!!

Could very well be true, but coming from a Unimat 3 it was quite a surprise. At a guess the lathe, accessories and motor would probably be near 70kg.

That or I’m getting old and it feels far heavier than it is

I could not help having a play with it and it chewed through some re-bar scrap I had and turned them into bar stock with a 0.02 variance over 200mm. Considering I just chucked it in and started turning with an unsharpened tool I am over the moon with the machine.

I can do similar on the Unimat, but the process is such mine field and the machine easily stalls, the Portass didn’t really care and made chips.

[mart7mcfl7Participant @mart7mcfl7]

I’ve got a spare bt of time before bed, I’m going to unscrew it!

 

[mart7mcfl7Participant @mart7mcfl7]

Good detective work Bill, thank you

[Dave Halford]

On Dave Halford Said:

It’s just possible that brass plate has been turned round. I can’t think of a reason to fit a blank one.

Alas, the back of the plate is blank. Very strange. I am lucky enough to own a Makera Z1 cnc and I can make a really fancy plate with all the info needed with a 0.3mm engraving tool, that is a job for another day though.

[old martParticipant @oldmart]

Do you have the tailstock?

[File HandleParticipant @filehandle]

My Portass Lathe doesn’t have a brass plate, but it does have the name on the bed casting. There where many variants of the model s including some that were rebadged by other sellers, typically removing the Portass name from the castings. I believe that others did copy the Portass as well.

Did your £90 get other items as well or just the lathe minus the tailstock.

[mart7mcfl7Participant @mart7mcfl7]

I’ll have to have a look at the castings tomorrow, thanks for the heads up buddy. The lathe came with a bit of steel tooling, tailstock, dead center and a chuck. With the 1hp gryphon motor I think I didn’t do too badly.

Today I’ve spent the spare time I’ve had removing the stuck chuck and slide and giving it a basic clean, debating if I want to go as far as taking the lathe fully apart but I can see shims between the bed and gear castings so I need to figure out how not to lose the setup before playing with it too much.

 

[File HandleParticipant @filehandle]

You would have seen the Portass in the casting – its large behind the lead screw, on the rear of mine is Made in Sheffield. A 1 Hp motor is a bit excessive for it, more typical 1/3 or 1/2. Yours looks like it has rib reinforcing on the casting near the gap. Lack of the Portass name probably means it was rebranded or a copy. It would be nice if all of the differences allowed for dating, but I don’t believe its hat simple.

[bernard towersParticipant @bernardtowers37738]

if you look at altona on lathes .co.uk site there is a Altona/portass S lathe in black that looks very similar.

[mart7mcfl7Participant @mart7mcfl7]

The only wording I’ve seen so far is behind the leadscrew handle, on the ways. It is stamped ‘S98’ and another area is stamped ‘E’

The machine is on at least its second paint job at the moment, so once I’ve cleaned up some of the old layers of paint I may very well find some more information.

As for the motor I’m inclined to partially restore it and sell it on to an enthusiast that appreciates such things, apparently the Brookes Gryphon was fitted to many Myford Lathes so I presume there is a market there.

For the replacement, im not such a stickler so I may go for a 800W 36v scooter motor with variable speed control, partly for control (this type of motor has been handy on the unimat) and since the Lathe is already much bigger than anticipated it would save a fair bit of workbench space.

[mart7mcfl7]

On mart7mcfl7 Said:

 

For the replacement, im not such a stickler so I may go for a 800W 36v scooter motor with variable speed control, partly for control (this type of motor has been handy on the unimat) and since the Lathe is already much bigger than anticipated it would save a fair bit of workbench space.

Just had a look at those, and they appear to be rated up to 2800rpm, as opposed to the 4 pole AC @ 1400, so make sure you don’t over speed the headstock bearings

Bill

[peak4]

On peak4 Said:

On mart7mcfl7 Said:

 

For the replacement, im not such a stickler so I may go for a 800W 36v scooter motor with variable speed control, partly for control (this type of motor has been handy on the unimat) and since the Lathe is already much bigger than anticipated it would save a fair bit of workbench space.

Just had a look at those, and they appear to be rated up to 2800rpm, as opposed to the 4 pole AC @ 1400, so make sure you don’t over speed the headstock bearings

Bill

A counter shaft hasn’t been mentioned with the original lathe. If the 1HP motor is driving the lathe directly then it will already be going too fast, to the detriment of the bronze bearings. Fitting an even faster motor with no way of reducing the speed will be asking for trouble. If the lathe was previously run directly from the motor with no countershaft in between then it is likely the the life of the bearing has already been compromised. However, it may be the the previous owner did use a countershaft, but kept it for a different use.

[JasonBModerator @jasonb]

Would that not depend on the size of the AC motor’s pulley, if small enough the bearings may not have been fried, particularly if the smallest lathe pulley was not used. Likewise the OP says he will use the Scooter motor with variable speed

[File HandleParticipant @filehandle]

Yes but to get the lathe down to a reasonable speed, even using the large pulley on the lathe the motor pulley will need to be really small,less than 1″ dia. This type of lathe was designed to run via a countershaft. Typical max of 700rpm. I guess it could be run using the backgear permanently engaged, but that wouldn’t allow any access to really low speeds.

[File Handle]

On File Handle Said:

Yes but to get the lathe down to a reasonable speed, even using the large pulley on the lathe the motor pulley will need to be really small,less than 1″ dia […]

Use a  Poly-V belt and small pulley

MichaelG.

[Author]

Posts