Hi, How mush under bend do i cut in the form?
Green curve is minus .100
Red curves are a tapered offset -.250 and -.500
from the zero at the waist.
Thanks for your experience!
Brian O.
Side Bender Springback prediction
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Re: Side Bender Springback prediction
My forms are to size. I heat and bend them about 15 minutes at 290 F then I let cool and heat them up again for 15 minutes blanket set for 290F. With this process the sides are pretty locked in. I have no problem with a little spring back. Are you bending with a with a heat blanket and form?
Re: Side Bender Springback prediction
Thanks for the reply, I will make the form (outer profile -.100) inward for the side thickness (estimate ?)
I am doing a mold and bending form. for a pro maker. I am a metal cutting/forming guy and have programmed metal parts for bending always being aware of "springback" Parts llie jet engine nacells and wings, doors.![Very Happy :D](./images/smilies/icon_e_biggrin.gif)
I am doing a mold and bending form. for a pro maker. I am a metal cutting/forming guy and have programmed metal parts for bending always being aware of "springback" Parts llie jet engine nacells and wings, doors.
![Very Happy :D](./images/smilies/icon_e_biggrin.gif)
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- Posts: 2712
- Joined: Fri Dec 23, 2011 8:33 pm
- Location: Seattle
- Contact:
Re: Side Bender Springback prediction
I bend at .080" so your .100 is good. From experience spring back for wood is variable bend to bend as wood is not consistent. When bending by hand without a form one can over bend slightly and then check. So basically bend check bend check ... As I mentioned before I have had good luck double cyclizing the heat time. The heat cool heat cool cycle does help lock in the bend. If working with a mold it is not a bad thing to pull it into the mold. I have seen some dubious posts where builders talk about building without tension. I find that odd given that the entire concept of a guitar is tension. Also the plates are cold forced into radius dished for example. So no real harm pulling a side into a mold. Once the top and back are glued on they are not going anywhere is not going anywhere.