Question on bending cherry

[Papa Jim]

I need to to put a very shallow bend in an piece of cherry 34" x 4-1/2" by 7/8" (arm rest for a chair I'm making). By shallow, I mean about 1/2" over the entire 34" length. As an experiment I clamped both ends to my table saw fence rail with a 1/2" spacer in the middle, so I know it will go. The question is how to keep it there. I would rather not have to invest in the time and money to build a steam box if there is some easier way. How about soaking it and then leaving it clamped in place till it dries? I've never heard of that being done so there is probably a good reason. How about it? Anybody got any ideas?

Papa Jim

[K. L. McReynolds]

I did a much greater curve with hard maple by soaking it for two days in water----seems like to me that would be ok with cherry.

[Stwood_]

Soaking in cold water will work. Being that thick, I would soak it for a week.
Cherry is brittle. I did bendable stair rails using cherry a couple of times and filled 4" pvc pipe (capped) with water (1/4" thick pieces) and left overnight, then clamped in place till dry.

Then when you bend it, over bend it, as it will spring back some. I would probably bend it about an inch and let dry for a week or so.

[Handplanesandmore]

Wood bending doesn't work that way, not for arm rests unless you aim at carpentry kind of work, rather than fine furniture. Relying on moisture to bend the workpiece means it is unpredictable how it would react and change to seasonal adjustments, or loss of moisture due to heat in the house, etc.

Either bend the proper way like laminating or bandsaw the curve out, if stable curvature is the goal. You need a bend form, too.

Why the rush? Learn the steam box way or other bending methods (heat bending) for good, and you can use the techniques acquired for future projects. A steam box is very easy and cheap to make (scrap ply, an electric kettle...youtube).

Simon

[mike4244]

I need to to put a very shallow bend in an piece of cherry 34" x 4-1/2" by 7/8" (arm rest for a chair I'm making). By shallow, I mean about 1/2" over the entire 34" length. As an experiment I clamped both ends to my table saw fence rail with a 1/2" spacer in the middle, so I know it will go. The question is how to keep it there. I would rather not have to invest in the time and money to build a steam box if there is some easier way. How about soaking it and then leaving it clamped in place till it dries? I've never heard of that being done so there is probably a good reason. How about it? Anybody got any ideas?

Papa Jim

Very easy to make a permanent bend. Make a wood trough by nailing two boards together  to form a Vee shape. nail two scraps ,one on each end to keep the  trough upright and close the ends. Add water to see if it leaks, a little bit of leaking won't matter. A lot means you have to caulk the joints. 
After getting to the point that leaks are controlled, add very hot or boiling water to the trough, then one bottle of water softener , I use Downy brand. Place the board in the trough. Remove when the water is tepid and clamp to a form. You may want to make the form a bit more of a radius in case of spring back. I would make the bend about 5/8". Probably spring back to 9/16" or 1/2".
mike

[Handplanesandmore]

Boiling water is a heating method used by some Japanese woodworkers for banding or basket handle work.

Simon

[rwe2156]

The simplest option is to cut a curve, which is how a lot of chairs are done.

Without steaming, wood tension will very likely overcome the bend unless construction of the chair will hold it.  But that's not the right way to do it.

If you don't want to steam, the only option is a bent lamination. 

For a bend this shallow I think you can bet by with thicker lamina (1/2"). 

Use epoxy & over bend it a bit.