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When I am making a new set of side bending forms I cut the waist 1/4" deeper and cut about 3/8" off the form at the neck and heal. That way I overbend slightly to help compensate for spring back. What are your views of this practice?

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Joe Beaver
Maker of Sawdust

I don't do the waist, but I do the neck and butt ends. To me it gives less spring back.
Tracy

Tracy,
About the same amount?

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Joe Beaver
Maker of Sawdust

I have never need that much compensation. I use to use a 1/8" at the end of the lb and ub but anymore I just take my finished shape minus side thickness and one back-up slat thickness off the finished shape and that is my bending form. I cook all excess moister out of my sides and let them stay clamped in the press overnight and I have not had any issues.

yes, about 1/4" to 3/8". I think it depends on if you had problems with spring back. I know a few builders who use 2 blankets with 2 steel slats in a sandwich, and they cook an extra few minutes after all is down, and they have no spring back. So it just depends. I don't have 2 blankets and I always have springback. So to fix this, I added this to my bending form.
Tracy

Yes, I do the same as Tracy. Here is how you figure it. Bend a set on a standard non-compensated form. Place it in position over the mold and see how much springback you have. Compensate that amount on the next mold.

I did about 3/8 and 3/4 " the last mold I built. Works Great. Nothing at the waist.

I have had to pull a set or two back just a little, so somewhere between the two would be good. Say 1/4 and 5/8 " works for me. Pulling slightly sprung sides in and gluing them will not be a problem either.

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http://www.dickeyguitars.com

In my opinion, the key is leaving a bent side in the machine overnight. It
takes a good "set" and fits the mold precisely. No overbending is needed.

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Sylvan
http://www.wellsguitars.com

Joe, does it work for you? If so, then it's a pretty good method.
Me, I don't over bend. But my bending method is a bit different than most. I bend, let it cool, heat it back up and take it out hot and it goes straight into the mold.
That works great for me.

My first form, classical, did spring back some. My next I allowed 1/4 at the waist and 3/8 at the ends. It worked pretty good but it seemed to depend a lot on the wood. My next is going to be for a cut-away so I want to make it as easy on myself as possible.

Like Paul, I heat, press it by hand onto the form then clamp. Then I let it cool, heat, cool and heat again. I let it cool overnight before I take it out.

After reading these great comments I think I might try 1/4 upper bout, 1/2 lower, and none at the waist.

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Joe Beaver
Maker of Sawdust

This thread reminds me of the Taylor Factory Fridays sidebending video. They take the hot, newly bent sides out of the bender, and straightaway to an open form/jig that holds the sides to shape. I'd love to see the details of that sideholding form/jig.

CrowDuck

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Chris Nielsen
Soquel, CA.

Yes ,I sanded mine down 1/4" on both ends and none on the waist. Terken: Yeah I figured that one out too

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Anderson Guitars
Clearwater,Fl. 33755

[QUOTE=tl507362] I don't do the waist, but I do the neck and butt ends. To me it gives less spring back.
Tracy[/QUOTE]

This is what I do.

Cheers Martin

I don't do any overbend to allow for spring back. Like Sylvan I like to leave a side in overnight after running a couple of cycles then before I take it out I heat it back up to temperature and while it is still hot take it out of the bender and put it straight into the mould (use gloves) then just tighten up the cauls. Spring back? What spring back!

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

As most of you guys know, i steamed bent my first sides and after that, i brought 'em straight to the mould and clamped them in there for the night and had just a little spring back, maybe because the steam was not hot enough or my bending set up wasn't holding well the heat through cracks, i just can't wait to see the difference a heat blaket and bulbs will make on my future builds though.