Cutaway bending

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JurgenV
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Cutaway bending

Post by JurgenV » Sat May 06, 2023 4:33 am

I am trying something new. Ok, not for most of you new, but for me. During the last almost ten years I built around 20 guitars which admittedly are now a lot better after finding Trevors books. But I actually never did a cutaway. So at the moment I´m thinking about buidling a cutaway version of my 000 model with pickup (which will be two new features at the same time).

Ok, I know I need to thin the cutaway area more and I even organized a veneer softener just in case. Usually I´m bending the sides with a DIY foxbender using some steel sheets I bought a long time ago. It´s not spring steel and I always have flatten it after use again. I´m quite sure I will get in trouble using this for the cutaway section as I feel it will be too stiff.
So finally my question: what is the thickness of the steel slats you are using when bending cutaways?
0.2mm / 0.3mm / 0.5mm ???

Is there anything I absolutely need to think of when upgrading my side bender for cutaway shapes?
Ohh and just in case that is important: I use a heating blanket with temperature control

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56nortondomy
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Re: Cutaway bending

Post by 56nortondomy » Sat May 06, 2023 4:36 pm

I use aluminium slats for bending, I've never had any problems with them going around the cutaway section. I'm not sure what thickness they are probably around .7mm. I have some SS slats as well but I've found them too stiff so I've never used them. Wayne

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Taffy Evans
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Re: Cutaway bending

Post by Taffy Evans » Sat May 06, 2023 7:01 pm

Hi, yes I've used aluminum for many years now. I got a handyman sheet of aluminum from the local hardware store and cut it to the sizes I needed. I just have to flatten it out after each bending operation.
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Dave M
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Re: Cutaway bending

Post by Dave M » Sun May 07, 2023 1:01 am

First of all I have to say that I admire people who can bend any shape over a hot pipe. I can't!

Any heat bending of timber requires support on the outside of the bend. The classic Fox bender provides this, particularly with the sprung support under the waist bend. You can find plenty of videos by the furniture makers as to how they do this.

The problem with the cutaway bend is that you have a double bend - an s bend if you will. So the steel slats on a conventional bender will only support the outside of one of the bends. I have a rather Heath Robinson bender which keeps tension on both of the spring steel slats. Not my idea but copied from someone generous on the web. It works well and I don't tend to get cracked sides even though I do quite sharply bent cutaways.

I think spring steel is the way to go. I bought mine from one of the two sites in America. I don't have an answer to your original question but they just work. You do though have to keep them away from the water and steam. I wrap the timber in Al foil.

A few pics should show the general idea.
Attachments
Binding 3 small.jpg
Bender 5 small.jpg
Bender 1 small.jpg
Bender 3 small.jpg
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Dave

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WJ Guitars
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Re: Cutaway bending

Post by WJ Guitars » Sun May 07, 2023 8:50 am

Here are some photos showing my fox bending machine of a cutaway. Of recent times I now use spring steel slats.

Wayne
Cutaway Bernding.jpg

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kiwigeo
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Re: Cutaway bending

Post by kiwigeo » Sun May 07, 2023 11:53 am

I'm an old fashioned outcast...I kitted up with bending forms and blankets but ended up going back to my trusty bending iron.

One advantage of a bending iron.....you never doze off while using it. Two pairs of shorts with holes burnt into them is proof of that!
Martin

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kiwigeo
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Re: Cutaway bending

Post by kiwigeo » Sun May 07, 2023 11:54 am

LOL....you never fail to impress with the clear and neat labeling of everything in your photos. Impressive.

WJ Guitars wrote:
Sun May 07, 2023 8:50 am
Here are some photos showing my fox bending machine of a cutaway. Of recent times I now use spring steel slats.

Wayne

Cutaway Bernding.jpg
Martin

JurgenV
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Re: Cutaway bending

Post by JurgenV » Sun May 07, 2023 6:55 pm

Thanks for your posts...

But the initial question is still not answered. If you´re using steel (or spring steel) which thickness are the slats you are using? :)

Btw. I like the idea of keeping both side under tension. Just need to find a way to incorporate it into the existing tool. And find some springs

Dave M
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Re: Cutaway bending

Post by Dave M » Sun May 07, 2023 8:37 pm

OK OK I'll go out to the workshop...

I don't have a micrometer but the spring steel I'm using is a little more than 0.2 mm. As I said it is the standard product from one of the two US guitar making shops.

Cheers Dave
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WJ Guitars
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Re: Cutaway bending

Post by WJ Guitars » Sun May 07, 2023 9:47 pm

kiwigeo wrote:
Sun May 07, 2023 11:54 am
LOL....you never fail to impress with the clear and neat labeling of everything in your photos. Impressive.

WJ Guitars wrote:
Sun May 07, 2023 8:50 am
Here are some photos showing my fox bending machine of a cutaway. Of recent times I now use spring steel slats.

Wayne

Cutaway Bernding.jpg
Thanks Martin. I hope that providing more detail is helpful for the forum.

Wayne
JurgenV wrote:
Sun May 07, 2023 6:55 pm
Thanks for your posts...

But the initial question is still not answered. If you´re using steel (or spring steel) which thickness are the slats you are using? :)

Btw. I like the idea of keeping both side under tension. Just need to find a way to incorporate it into the existing tool. And find some springs
For spring steel slat sizes available from LMI see below.

Wayne
Spring Steel slats.png

Dave M
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Re: Cutaway bending

Post by Dave M » Mon May 08, 2023 1:01 am

Wayne I have to say that your posts are always helpful/interesting. As to labelling - as the brain cells shrivel it is really worth noting down what each funny shaped bit of wood is actually used for when you pick it up after a few months!

Cheers Dave
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Dave

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Mark McLean
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Re: Cutaway bending

Post by Mark McLean » Mon May 08, 2023 3:25 am

I am like Martin and have always just stuck with bending by hand on a hot pipe. I do this because I tend to make a different size or shape instrument each time and I don’t like the idea of making a new bending form for each guitar, and also the space that a Fox style rig would require. I have not had any trouble doing cutaway bends by hand if the wood is thin enough (2mm or less) and using a steel slat on the outside and a veneer softener like Super Soft 2. And bending by hand just feels very satisfying.

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