# steam bending some quartersawn air dried red oak



## dorran (Jul 18, 2009)

I am getting ready to steam bend some chair back slats for a Morris chair. The plans call for a 36" radius bend. I made a form with a 34" radius to allow for some spring back. My question is how long to do I have to keep the wood in the form? I only made 1 form and would like to steam all the slats at the same time. Will the spring back diminish after initial cooling (5 minutes) or does it have to be held until it is dry again(hours, days, weeks, months, years)?

Thanks for any experience with this.
Dorran


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## richgreer (Dec 25, 2009)

I have not actually done this but I have seen several videos on the subject. It's my understanding that you need to leave the wood in the form until it drys completely. That could be more than a week.


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## dorran (Jul 18, 2009)

OK. Thanks. The bend didn't seem all that extreme so I thought it could be less. The wood is 3/4" thick. Maybe I need more forms or another way to hold as it dries.


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## tbone (Apr 24, 2008)

I've only bent white oak, but I always leave it clamped in the form about 24 hours. Naturally, there is some springback immediately. However, it *could* spring back a little bit more over the next couple of days. Once it quits moving, it will stay that way from then on.

By the way, I think curved backslats on that Morris chair is a tremendous improvement in comfort.

Good luck.


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## TheDane (May 15, 2008)

Dorran-I would go for more forms and longer dry time.

When I built my Morris Chair, I left the red oak stock clamped in the form for 7 days … had minimal springback.

-Gerry


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## Howie (May 25, 2010)

you could leave it in the form and use a heat gun to expidite the drying. I do that all the time.


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## shipwright (Sep 27, 2010)

You could also let it cool in the form and then, since it's an even radius, just string it like a bow while it dries out. The initial bend stretched and pulled the fibers. Now all you're doing is preventing them from returning, a much lesser force is required.


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## dorran (Jul 18, 2009)

Thank you all for the very good advice. I will make some more forms for holding the shape, wait at least 24 hrs, and try a heat gun if I get impatient. Now I just have to wait for the cold and snow to go away.


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## Loren (May 30, 2008)

Bend the slats into the form and hit them with compressed air - helps
set the bend (luthier trick). Then take them out and put them in a 
drying form that overbends them a bit.

Leave the wood in the forms for quite a while. I saw a shop where the
guy had drying forms all over the walls. They were pretty simple but
held the bends all in the same shape. Presumably he bent more than
he needed and used the ones that matched up best.

If you bevel the 4 edges of each piece a little it can help prevent splitting.


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## Howie (May 25, 2010)

Loren, learned another trick..thanks


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## tenontim (Feb 24, 2008)

I leave my pieces in the forms for several days until dry. You don't have much time for getting the bend if you're using kiln dried wood. Set everything up to get the piece bent as quickly as possible. The quicker it's bent, the less spring back you'll have. I get mine from the steamer and clamped in the form in about 10 seconds. Air dried wood is better for bending, if you can get it, and you have about 10 minutes to bend it. That's the way I do it.


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## dorran (Jul 18, 2009)

Steamed today with some success. I built a bending form and a drying rack/form. My set-up took a long time to get up to temperature. I ran the grill for 7 hours total to boil a few gallons of water. 6 back slats loaded 3 at a time in a 4" pvc pipe. The other snag was the steam swollen wood got stuck in the pvc steam chamber. Lesson learned. If it's snug going in cold, it won't come out hot.

Thanks for the help.
Dorran


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## tbone (Apr 24, 2008)

Good job dorran!
You can shorten the time it takes to get to the boiling point if you first heat it up on the stove in the house.

My set-up is a length of 6" PVC pipe, a Coleman camp stove, and an UNUSED steel gas can with a radiator hose connecting the can to the steam chamber. (If the Homeland Security boys ever busted into my garage, I might have some explaining to do before they figured it out)


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## misbeshavings (Feb 28, 2011)

where did you get your plans for the chair?

anyone got a favorite? I'm planning on a couple this spring, and can't decide which plan I like best.


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