Steambending )(#@*%^

[Marcus Ward]

So I'm bending the pieces for the arms of my wife's morris chair and I bent one the wrong direction. Anyone want to say whether or not I can steam it and rebend it the right way or will I have to make a new arm? ARGH!!! Measure twice, cut once, and check which way the piece is lying!!:mad:

[harry strasil]

only one way to find out.

[Marcus Ward]

True, brother. However, if I'm going to fire the boiler back up for 90 minutes I might as well use a new piece instead of steaming the bent one and it maybe not working. I was hoping someone here had done it. I'm going to hang it on my shop wall as a reminder to pay attention!

[harry strasil]

don't know how big your steamer is, but why not steam both pieces at the same time and try rebending just for future reference?

My steamer is a 6 foot long piece of 6 inch pipe, on legs tilted up to the end you insert, I use a 6 inch pipe boiler with a piece of radiator hose to the boiler which sets on a single hot plate, all the accumulated moisture runs back into the boiler pot.

I have never had any luck steam bending kiln dried wood, even straight grained, but I have only been making small full circle bends 10 to 16 inches in diameter for rims for old wooden wheel rims for old childs wagon restorations.

http://img.photobucket.com/albums/v81/irnsrgn/lilwgn2.jpg

[Bob Smalser]

Once it's cold, it's too late.

[Ray Knight]

The prior posting is absolutely correct. You really can't do much bending with kiln dried lumber. Made my first shaker rocker, bending jig to get 3-4 inch nice arc on the back posts. Several weeks getting the next one done, steamed the bejeezus out of it, spring back, not much more than 1 in permanent arc. Thought it was my steam box, hot plate and gorgeous old copper teakettle and radiator hose. Got a turkey roaster, made lots more real steam, same result. Finally read or was told that kiln drying locks the lignin, and that's the way it is. Just scored 350 bf of air dryed band saw milled cherry from craigslist, so will be starting again soon. Ray Knight

[harry strasil]

only way to really get good steam bending in my opinion is to use only air dried or green wood, rived (split) from a log.

Kiln drying makes lumber brittle.

[Marcus Ward]

Well, I'm pretty sure this stuff is kiln dried and it bent fine. It's 1" thick 5" wide white oak that I'm bending on a 6' radius and it did great. I'm not making wheels, however. I will keep all the tips in mind. My steam box is 4' of 6" stove pipe, capped on the ends with oak plugs. 3/4 radiator hose running to it. My kettle is a 1/2 barrel stainless keg with a 12" hole cut in the top sitting on a high powered turkey fryer. I typically make beer with this kettle and it'll take 15 gallons to a rolling boil easily. I ran it 3 hours and only boiled off about 1/3 of the 10 gallons I started with.

[Bob Smalser]

I recommend the UK Forest Product Lab's Wood Bending Handbook available at Amazon and the reprint available at DN Goodchild of Wood, a Manual for Use in Shipbuilding by the US Forest Products Lab and USN Bureau of Ships.

1) Airdried wood at 12-16% MC bends just as well as green wood at 30%, but without the shrinkage and degrade that comes later after it dries to the 7% it will stabilize at in the house.

2) Kilned wood is certainly bendable, but with a higher failure rate than airdried wood. You don't think all that mahogany for all those fancy speedboats out there is shipped green and molding from Africa and Honduras, do you? But kilning is a complicated topic and there is certainly lots of overcooked and brittle wood out there.

3) The single largest factor in successful steambending is zero grain runout.

4) The second largest factor in successful steambending is picking the right species. The books tell you what radii are possible both strapped and unstrapped.

Note the steel strap backing up the stretched surface of the bending stock on this bending jig:

http://pic20.picturetrail.com/VOL12/1104763/2595357/91769644.jpg

[Bill Houghton]

Harry,

That's truly a driveby gloat. Pretty little thing!

[josh bjork]

Marcus, you can bend that wood that much by just getting it good and hot. However, it is easy to leave scorch marks with a heatgun. My experience echos bob's post except I've never seen that book. WO is a good wood for bending.

I've tried to bend some tropicals with no success ever after boiling in a pot.