Finnish lathe

[jjj]

I was lucky enough to be in Finland this week and went to an exhibition entitled made in Helsinki 1700 to 2012. I saw the lathe pictured below and thought some of you out there would be interested.

A sturdy piece of kit?

Cheers
JjJ

[jrccaim]

A very clear example of a continous-motion lathe. Not a pole lathe at all. Note the flywheel and the crank. When it was made I cannot say; but the design is late 19th century, or even early 20th. Flywheel is cast-iron with steel crank and axles. It also illustrates a problem that has come up elsewhere on this forum. You certainly could not buy such a lathe nowadays. Not for sale; we haven't made them for a century. Might be able to salvage one off a scrap heap. Pure luck if you did. I wish you lots of luck! If you want to make one your problem is to make the flywheel; so unless you can make castings in iron you would certainly have to improvise. This is a fascinating subject but it is not a pole lathe. Maybe we need a new topic for continous motion lathes, and I myself am interested in it, but until I see more interest I will not advocate a new heading.

[magnet]

you can cast a concrete flywheel .......magnet

[jrccaim]

you can cast a concrete flywheel .......magnet

Abssolutely. Have you tried it? I do lots of concrete work. You need to build a form. The form must be perfectly circular. So you have to bend wood to this shape. Perhaps a half-meter (or more) diameter. Plywood recommended. Regular wood requires steaming. Major issue, see other posts on steaming this forum. Even plywood might need steam, unless you can get your hands on 3mm plywood. And how shall we reinforce it? Wire mesh maybe. Or steel strapping tape, both of which I have used. If you build anything out of concrete you should have steel reinforcing because concrete is marvelous under compressive force but really bad at tension. That is why we try to reinforce it. That's why "rebar" which is short for "reinforcing bar" exists. And then you have to make sure the reinforcing is well distributed so's you have a balanced flywheel. I do not say that a concrete flywheel is impossible. In fact out there on the net there are plans for just such an animal. Google on "treadle lathe" and ye shall find it eventually. But it is a lot of work! Not as simple as adding water to DIY mix bags.

For the above reasons I think, but am willing to change my mind, that your best bet is to find a nice circular piece of steel or cast iron that you could use. I have in my shop an old automobille clutch plate. Just the thing. Alas it has an enormous hole in the center, at least 35mm and I need to plug it. But UK bodgers have a huge advantage over me. You have piles of Industrial revolution scrap lying around by the ton (or tonne if we metricate). Make use of it! It is what they call a "competitive advantage" in industry. Were I in the UK I would haunt scrapyards if I wanted a flywheel. Who knows. Your scrapyard hunts might even yield you a Brittania or Relmac treadle lathe intact! Most certainly will be rusty. Bearings almost certainly shot. We can deal with this. With much less trouble than pouring a concrete flywheel. Be grateful, Britons, and sally forth in searchg of flywheels.

Oops. Just thought of another flywheel source. An old-fashioned sewing machine. Built-in treadle and flywheel. Still some of them around; fast becoming collector's pieces in this country. If you find one you colud use it as the basis for a treadle lathe.

[AlexanderTheLate]

Just to throw out some ideas:
What about an old oil drum filled with water? A bit of welding to make it usable.
or an old skidder wheel rim? Those things are huge and heavy like nothing.

But really, it does not have to be really heavy, just heavier then what you' are turning.

[Bob_Fleet]

You need to build a form. The form must be perfectly circular.

I used the plastic off large blue 50 gallon barrels as a former for paving stones but don't see why an appropriately thick slice couldn't be used to cast a flywheel.
Single use and cut it off when set too.

[jrccaim]

I used the plastic off large blue 50 gallon barrels as a former for paving stones but don't see why an appropriately thick slice couldn't be used to cast a flywheel.
Single use and cut it off when set too.

Oh, I agree with you one hundred percent. It is not impossible. It is just difficult. How will you get your centre hole on the plastic barrel to come out in the right place? How will you reinforce it? Once you've cast a concrete flywheel there is no way to true it up (short of using high-tech things like diamond cutters) so if you made an error in spotting the centre you have a lopsided flywheel. If you mislocated the centre by 0.1 mm it will make no difference. But the more you mislocated the centre the wonkier your flywheel and the more troubles you will have. Not impossible, I say again. Just tricky.

Our forefathers used wood for flywheels. Perfectly valid. To make a usable wood wheel you would need at least 60 cm diameter and this is what Roy Underhill did -- go see his videos and books. And he used plumbing parts for most of it. I do not say that it is impossible to make a continous-motion lathe. I do say that if someone else made the flywheel for you it would be easier. Flywheel and crank are the essential parts of continous-motion lathes. And most of us are in no shape to produce cast-iron flywheels from patterns. Cast iron better than wood for flywheels. Much denser, you see; equation is m*r*r where m is mass and r is radius. You can go a long way with a smaller iron flywheel. It's all about inertia. This is why my current search is for industrial revolution castoffs. Literally. They cast them and they neglected them. Even an old sewing machine flywheel would let you do quite a few turned objects.

[Bob_Fleet]

Try your local tractor or truck repair garage.
Their flywheels are really heavy and seem to get replaced leaving scrap ones for the asking.
I never thought about it but my main bowl lathe (powered) has two underneath it just as ballast.
It also has half a harrow inside and I still danced it with large natural edged timber so have it bolted to the floor as well.
I have a Union treadle lathe which I thought would be good for demos but the weight, especially the flywheel, makes it impractical to transport easily.
Meanwhile back to the joys of pole lathe ......

[ToneWood]

Great looking lathe. Looks "robust" (strong, simple, effective) doesn't it.

Re. flywheels, I have some big old American metal barbell weights under my work bench on a shelf for ballast, the big ones (25lb?) would probably make good flywheels.
I came across my brother's old York concrete-filled-plastic barbell weights outside recently - the sort of thing that often turn up on Freecycle.

[jrccaim]

Great looking lathe. Looks "robust" (strong, simple, effective) doesn't it.

Re. flywheels, I have some big old American metal barbell weights under my work bench on a shelf for ballast, the big ones (25lb?) would probably made good flywheels.
I came across my brothers old York concrete-filled-plastic barbell weights outside recently - the sort of thing that often turn up on Freecycle.

One trouble with barbell weights is the size of the center hole. In US it is at least one inch (25 mm). So you are into some rather large bearings. Not impossible at all, just difficult. If you had a piece of 25 mm shaft and were willing to run steel shaft on wood bearings you could do it. But then you have that problem of driving the headstock, no groove in the rim of barbells for a belt. And how are you going you do the crank? Oh, you say, I'll put a U bend on 1" steel shaft. Good luck with that. All of these problems can be solved. Don't mean to discourage you at all; but a muscle powered continous motion lathe is a lot more work than a pole lathe. I can do a pole lathe (and have) working part-time in a week. A continous lathe would take me a month at least. In Britain, at least you might find and old Relmac or Brittania to name a few popular makes, in a scrapyard. It would be much easier to recondition one of those babies than to build one from scratch. Some of these would even turn metal. Much easier to build a rest to fit the ways than to build a whole lathe.

Here in Alaska we have practically no scrapyards. All our scrap is shipped via barge to Seattle. This provides gainful employment for barge companies (they ship practically the world up northbound and ship scrap back on the return trip) ) and is recycle-friendly. But it's a nuisance to scrapyard scavengers

[Simon Hartley]

Our forefathers used wood for flywheels.

Yes, but you would need a lathe to make it!

[Robin Fawcett]

I have a cast iron Victorian treadle lathe which I may be prepared to sell given the right offer. I think it may have been also driven by a line shaft at some point. Comes with loads of bits and pieces eg engineers slide rest and Axminster 4 jaw scroll chuck, spare(?!) headstock, faceplate. Would probably cost a fortune to ship to US!

Treadle lathe.jpg (1 MiB) Viewed 10930 times

[bulldawg_65]

I'd be right on that if I lived in the UK... That is a beautiful machine!