BillinDetroit
I learned alot by reading up about steam bending from this
publication. http://www.fpl.fs.fed.us/documnts/usda/tb1267.pdf
also try thhis link, http://www.woodweb.com/KnowledgeBase/KBBWGeneral.
Go to group alt.binaries.pictures.woodworking. I posted pics of two
curved shelf facings I bent. I'll add it was a challenge.
Francis



On Sun, 12 Aug 2007 21:55:05 GMT, Phisherman wrote:

On Thu, 09 Aug 2007 23:43:36 -0400, BillinDetroit
wrote:

Phisherman wrote:
You can remove the wood from the form after it cools. Expect
8% springback.


I am -simply- curious about this. Where did you get this figure and how
do you calculate for it in making a jig? I have a design in mind that
will call for a curve terminating in a 90 deg. turn as below:


=========|||


and I am in the head-scratching phase of the jig design, having never
bent wood (at all) before.


Bill

The 8% springback is a guideline. It may be 5%, so you should design
your bending jig with the thought that it may require a slight angle
adjustment. If the jig is at an 84-degree angle, your wood, after it
has cooled in the jig, will springback to abut 90 degrees. Different
thickness and wood type make a difference. There are all kinds of
steam bending jig designs and you need one where you can easily and
quickly put the steamed wood into it and clamped without any fuss.
Steam burns hurt--use care and leather gloves.