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Re: bending w/ steam / heat
By:Les Nightingill
Date: 8/2/2001, 4:39 pm
In Response To: bending w/ steam / heat (Will Dickinson)

Oh dear, I think it may have been me who led you to buy a heat gun...

I have used one with great success. I use heat only, no water. I concluded that you pretty much have to heat the strip enough that it's hot all the way through. This takes a little time (say around two minutes to heat a two foot stretch of 1/4" cedar). I was heating the cedar to just below the point of scorching it, it started to give a pleasant cedar fragrance at that point.

I don't know about redwood, but I believe it's not as flexible as cedar.

The strips DO retain some "memory" of their straight shape, and you have to bend/twist them further than you need while heating. You develop a feel for just how much. I use weights and clamps to bend or twist the strips while heating.

I first tried an experiment... you may wish to try this with your redwood. I clamped a short strip and applied torque to the other end using a bar clamp, with just the weight of the clamp as the torque force. I then heated the strip with my heat gun and after a couple of minutes the cedar readily yielded to the torque force and twisted with the weight of the clamp. Then let it cool (this is important, cooling while still under tension) and remove the force. It did not spring back very much and I had a 2ft strip of cedar with a 180 degree twist in it.

I hope this helps. At least try it before you make or buy a steaming apparatus.

regards

Les

: Ok, I wrote in a couple of weeks ago about having trouble getting my strips
: to bend into shape at the bow and sterm of the one-oceans cape anne double
: I am building. I got back lots of good ideas and suggestions, one of which
: involved the use of a heat gun on the sections of strip with the most
: curvature. I went out and got a middle-of-the-line heat gun (high &
: low heat setting)to try this method out. I think I am doing something
: wrong, because this does not seem to be helping bend the strips a whole
: lot. Here is my method: 1) saturate a cloth in water and wrap it around
: the strip, squeezing the cloth as I move it along the portion of the strip
: I want to bend. This gets the entire outside of the strip saturated.

: 2) Turn the gun on high and move back and forth across the now wet strip. I
: stop when the water is almost all evaporated and try to bend the strip.

: 3) bend the strips. The wood is redwood. The heating doesn't seem to change
: the load I have to apply to get the strips to bend. Also, the strips
: spring back to an almost straight shape even after being un-clamped (If I
: don't apply glue)

: I do not have any experience with steaming wood, and I think that this method
: with the heat gun is an attempt to "steam" without using a
: chamber. Maybe I should just suck it up and build a small steam box. Here
: are my questions: - Do you have to SOAK the strip instead of just wiping
: with water?
: - How high of a heat and for how long?
: - When do you remove the heat? When the strip is damp? dry?
: - Do you glue the strip immediately after bending, or just clamp in place and
: let it dry in the bent shape? If the strip is still wet after bending,
: will regular titebond create a good joint? Same question for regulare
: steaming...do you glue when the wood is still wet?

: Thanks for the help....it is really appreciated

: ---Will

Messages In This Thread

bending w/ steam / heat
Will Dickinson -- 8/2/2001, 4:23 pm
Re: bending w/ steam / heat
Ken Sutherland -- 8/5/2001, 7:21 pm
Re: bending w/ steam / heat
brett onnink -- 8/4/2001, 10:54 am
Re: bending w/ steam / heat
Chris Menard -- 8/3/2001, 8:01 am
Re: bending w/ steam / heat
Rod -- 8/3/2001, 1:55 pm
Re: bending w/ steam / heat
John Monfoe -- 8/3/2001, 4:27 am
Re: bending w/ steam / heat
Les Nightingill -- 8/2/2001, 4:39 pm
Re: bending w/ steam / heat
West -- 8/2/2001, 4:51 pm
Re: bending w/ steam / heat
JT -- 8/2/2001, 5:35 pm
Re: bending w/ steam / heat
Chip Sandresky -- 8/2/2001, 4:39 pm