On Jun 25, 10:36 am, Todd wrote:
A piece of 1" red oak can be bent to radius of 1" if supported by a
metal strap and 11.5" unsupported according to "wood Bending Handbook"
published by Woodcraft Supply.

I think you meant that one inch oak can be bent to a radius of one
foot! I am sure most caught that though.

That sounds about right to me as long
as the strap is fixed at both ends so that the neutral axis is pushed
to the outer radius. Also, remember that it is primarily the heat that
plasticizes wood and that you do not gain any additional softening by
heating the wood beyond the boiling point of water.

Exactly, if you heat it to much it either crushes, or tears. Like I
said, a general rule is 15 min/quarter inch of thickness.

Luthiers use dry
heat as did barrel makers. I have never had very good results from
simply getting the work piece wet, it must get hot.

If you need to do further testing for your application before building
a steam box you can try boiling the piece of wood or wrapping the
section that you need to bend in rags and pour lots and lots of
boiling water over the rags.

I don't think you could get enough consistancy with rags on 1 inch
thick oak. I think the benefit of wet wood is transfering heat more
evenly thorough the piece.


Leverage helps but does not prevent breaking or crushing the grain on
the inner radius. Bending over matched male and female forms with
plenty of clamps does help.

A note. Once wood has been steamed once, the cells will not soften
again with heat. Also, when you remove the part from the steam, you
have literally seconds, maybe 7-10 to get the part bent or it will
cool and lose it's ability to bend, it will most likely crack. Always
make your radius a little smaller, it is much easier to open up a
radius part later that way, than to try to bend it more closed on
installation. You must also leave an extra foot or more on each end of
1 inch oak so you have some leverage, even after steaming, 1 inch oak
is no party to bend. Lastly, always wear protective eyewear and
optional other safety gear when working with steam, wood, fire, etc.
Good luck and move quickly and in a predetermined manner and you
should be fine.