Pole Lathe Capabilities?

[ilerner2]

Gentlemen, I am wanting to build a lathe for turning cylinders/spindles 9 inches in diameter x 5 feet in length. Would it be unreasonable to consider doing this on a spring pole lathe? I'm thinking with that much wood mass it would take a while for it to slow down - reverse directions - only to have to slow down and repeat. Perhaps a treadle lathe would be better suited to such a task?

My concern is that the rotational mass of such a large hunk of wood would/could over power the spring pole, bungie or other such motor and break it as the inertial forces of a large piece like this would not want to be stopped so quickly.

I originally posted this over in the Tools section but only got one response. Fingers x'd for better results here. Thanks

[woodness sake]

Such turning would require an extremely heavy and resilient pole and a long/heavy treadle to offset the mass of the work piece. Also, bear in mind that the spring pole lathe is primarily a green wood working device. The piece will have to be made from straight, clear wood and will likely dry with an ovoid section. Some species are lass prone to this but you probably have a particular wood in mind for the end purpose. Turning dry/seasoned wood is not out of the question, but the difficulties of this are prohibitive. You could simply go on as though you don't know any better and muddle right through the whole thing.
Also, consider using relatively under sized tools and gouges with a high sweep, # 8 or better.

[Simon Hartley]

I think that the major problem you would face is not the length or the mass, but the diameter. Each stroke of the treadle only pulls a given length of cord. If the billet is thin, it will turn several times by the time the treadle hits the floor. I have turned wood about 6" and it was noticeable how few turns I got with each stroke. 9" is really pushing it; you would need to pull over 28" of cord to get just one turn.

There is a YouTube video of Japanese craftsmen preparing large poles: https://www.youtube.com/watch?v=UqT-H8XdDzE

[davestovell]

Have you considered a treadle lathe or one with a flywheel.