Twisted Bed & Oak Poppets

[JermyB]

Just getting started by building myself a polelathe. it is based around the Mike Abbot book design with a few minor modification for making it more portable. I have already made the 2x "A" frames at the ends I am am coming onto the bed. I managed to get some lovely oak boards from a National Trust property but one of them has a twist. I was hoping that when bolted together it may straighten out. See below a picture of the bed with bolts tight at one end, and loose at the near end.

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All though I noticed the twist when I picked up the wood the picture here shows the severity.

When I tighten the bolts the twist does sort of come out but it then starts to twist the A frame. In the picture below you can see the bed with the bolts tightened and the near left hand A frame leg is now up in the air. You can also see angle difference between A frames.

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It would be a real shame to discard this bit of wood. Does anyone have any tricks for straightening out twists?

On a completely different subject I also have some lovely short oak boards which would make ideal poppets. I have read that you should avoid oak as the tanning corrodes the spindle bolts. Would this still occur is I used Stainless steel threaded bar and associated parts?

[woodness sake]

Since the main goal is to have two relatively level centers in space to hang a piece of wood between so it can be made to rotate, whether the bed is twisted or not is a matter of aesthetics, somewhat of an irony when considering pole lathing. By all means, don't discard what you have. Use it while you learn with it.

[JermyB]

Since the main goal is to have two relatively level centers in space to hang a piece of wood between so it can be made to rotate, whether the bed is twisted or not is a matter of aesthetics, somewhat of an irony when considering pole lathing. By all means, don't discard what you have. Use it while you learn with it.

It's not really the aesthetics that is of a concern. Its more that when tightened it lifts one of the legs in the air and so it rocks on two opposing legs. I suppose I could cut the legs to a different length but I'm just not that comfortable with this option. I fear I may have come across a downside to one of my personality traits before I have even started, "the will to get everything right first time". I am guessing with the nature of pole lathing I may find this trait comes back to bite me a few more times.

[Kevin Downing]

If you now only concerned with one leg in the air, then you could use a wedge under it when setting up in different places. A large wedge could be a piece of plywood with say, a 4x2 nailed to one edge of the plywood.

[arth]

When I have some warpped wood I soak it and lay it on something flat and put some weight on it. Some heavy logs or a couple of bins full of water. Keep watering the wood. It takes a few weeks.

[woodness sake]

replace the bed boards. everything else looks great

[SeanHellman]

The joys of using oak.
Oak is a wonderful material, and I use it a lot, it does have a habit of moving, that is twisting or warping. I know this from personal experience of making a table from oak which had been cut and dried for over 10 years. I took this table around shows for a few years and it experienced very damp and very hot conditions, and it was fine. Over one winter it was stored in a dry, temperature stable store room, and when I got it out it had split along some of the glue lines! Oak moves and can take years to do so.

[jrccaim]

arth said:

When I have some warpped wood I soak it and lay it on something flat and put some weight on it. Some heavy logs or a couple of bins full of water. Keep watering the wood. It takes a few weeks.

Soaking has worked for me. But if you have a steambox, steaming works faster than water. The real problem is holding it still while it dries out. I use a 20-liter canning kettle full of water, and if I could find a 50 or 100 Kg weight I'd use it. If I could lift it. Maybe if I drove the car (or the tractor) over it...

That is an appealing lathe, Sean.

[Donald Todd]

I don't know what you intend to turn, but the obvious answer is to make a single bed lathe, as in "Living Wood", if you are doing spindle work. You would then have two lathe beds!
My lathe here (15 years old) is very similar, but lighter, without the hinged legs. One of my Rails (Mahogany) has warped a bit making the poppets a bit stiff.

[RichardLaw]

Being a bloke of the quick and dirty persuasion, my solution would be to make and glue a small wedge to fit the gap between the twisted bed and the upright. The bed will then tighten up against the wedge and the legs will be OK. The fact that the two beds will be a bit wider at one end probably will not matter in the context of the whole scheme of the universe, which I believe contains some rather devastatingly large, and some as yet undiscovered, twists (some of which are responsible for the differences between bankers' and greenwoodworkers' bonuses).

[RichardLaw]

Not many people seem to favour the plans posted here: http://www.bodgers.org.uk/plans-menu/56-making-a-treadle-or-pole-lathe on this site by Hugh. My traveller is to this pattern and I find it very sturdy, I think the lower center of gravity is it's main advantage. I did use rather over-sized timbers too e.g the legs are about 4 x 3 and the feet about 6 x 3 - nothing like over-engineering!