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So I'm building my first guitar, a L-00, and I made a bending form out of laminated 3/4 plywood, and I use a sandwich of thin steel sheet, wood wrapped in wet kraft paper, alum. foil, heating blanket, metal sheet. My wood is Ovangol. I placed wood under waist caul, and turned blanket on. When it reached about 200 I started to feel the wood give so I started compressing the waist, then lower bout, then upper bout. By the time I was at 300, I was done and the sides were bent. I held it at 300 degree(temp regulator) till it stopped steaming, then turned it off. When it got down to 200, I ran it up to 300, and I did this a couple more times.

Then I left it on the form till it was completely cool, then pulled it off and bent the other side.

Sides fit in the form well, and all was good till I pulled both sides out.

I have pretty significant spring back. The wood wants to go back, and the waist gets wider, and it loses it's shape.

Please help! Any ideas would be greatly appreciated!!

Sean

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When you put it back in the form and put the spreaders in will it go back to shape without too much resistance?

Yes it does go in with not much trouble. Do you think after I glue in the neck and tail block, and glue the kerfing on, that it will then hold it's shape?

_________________
change isn't synonymous with improvement
instagram.com/bucketguitars/

I'm no expert and have never worked with ovangol, but I've bent 10 or so sets of sides in my bender and I've had springback in every side I've bent. Once you glue the blocks in, it will hold it's shape better, but still may contort a bit. The linings won't hold anything together. As long as you glue your blocks, linings, and top/back plates on solidly, it should hold itself together just fine. Of course, this is all assuming the springback is somewhat minor. What I usually do when I bend sides is to first use my bending machine and then touch the sides up on a hot pipe to eliminate as much springback as possible and get as close to the final shape as possible. This is an especially helpful system for bindings! Good luck to you!

Thanks for that bit of advice. I figured it would stay together okay, especially once the top and back was on, but I read that too much spring back can have an adverse effect on the top's ability to freely vibrate. Anyone know about this? Thanks again, I think I'll try touch it up with the heat blanket again, while it is in the mold.

Sean

_________________
change isn't synonymous with improvement
instagram.com/bucketguitars/

"I read that too much spring back can have an adverse effect on the top's ability to freely vibrate. "

Sounds good but I know of absolutely no evidence that it's true. It's one of those internet "lutherie is mystical" myths. Also, the wood will creep, relieving any stress, in a very short amount of time so the whole issue is moot. If it moves into shape with light pressure, glue in the blocks and build the guitar. There are many more important factors to worry about.

Thanks for the advice, and it makes sense. I don't think I'll worry about it. It does go in the mold pretty easy, plus I will be gluing the top and back on using my go bar deck and radius dishes while th body is still in the mold. Thanks again.

Sean

_________________
change isn't synonymous with improvement
instagram.com/bucketguitars/