Intentionally warping wood

[Stan Calow]

I want to take a 5/4 piece of kiln-dried walnut, 12" x 18" and get it to bow along the long axis just enough to put a slight curve into it. Any suggestions on how to do that? I've had plenty of wood do that on its own while I wasn't looking, but I dont know if you can do that without cupping as well.

Thanks

[Keegan Shields]

Steam bending would be my approach. Lots of ways to accomplish this, but you'll need a way to steam the wood and a form to bend it around.

[Stan Calow]

Keegan, yes I understand steam bending, but give the thickness of the piece, I dont think thats practical. I am not looking at laminating either or carving. I was hoping someone had experience by strategic wetting/drying to get a bow. In other words, mimicking a natural tendency.

[Frank Pratt]

In my experience, wetting & drying provides only temporary change. The wood eventually returns to its previous shape. You need heat to soften the lignin to put a permanent curve in it.

Check out this video, https://www.youtube.com/watch?v=mHAbShWQ7JI where the guy puts some radical bends some pretty heavy duty oak.

[Jim Becker]

What Frank said with the addition that KD has already limited the ability to bend it by normal means because of the heat used for drying.

[Stan Calow]

Thanks guys. I may spend some time combing the stacks at my suppliers looking for something with a bow in it already.

[Richard Coers]

What steaming does is relax the lignin so the cells can move, then stabilize when the wood cools and dries. Kiln dried wood not only is more brittle than air dried, but the grain direction makes a huge difference. If the grain runs out towards the edge, you stand a high chance of cracking. Hand split green wood is the direct opposite for working compared to what you have.