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PostPosted: Sat Jul 17, 2021 2:14 pm 
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Koa
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I’ve been using a Fox bending jig for twenty years, and have never liked the cutaway solution. Something like in this picture. Image


It’s bulky and seems to come at the cutaway at a bad angle. I’ve notice factory jigs tend to press in line with the guitar centerline.

In any case, if love to see if anyone has come up with a better mousetrap in this community. How do you get your cutaways bent?


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PostPosted: Sat Jul 17, 2021 3:44 pm 
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Koa
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My setup is basically an adjustable Fox bender. You can change the waist location as well as the center of effort for the cutaway. Works great!


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These users thanked the author Michaeldc for the post: Pmaj7 (Sun Jul 18, 2021 12:53 pm)
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PostPosted: Sat Jul 17, 2021 3:48 pm 
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I use this to bend Florentine cutaways. I have not done a Venetian.

Image

Image

Image


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These users thanked the author James Orr for the post: Tim Mullin (Sat Jul 17, 2021 7:37 pm)
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PostPosted: Sat Jul 17, 2021 9:16 pm 
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I love this bender Dan Koentopp uses.
https://www.youtube.com/watch?v=HQMgt_kkMA0

Kent



These users thanked the author kfish for the post (total 5): Joe Beaver (Sat Jul 24, 2021 4:33 pm) • Pmaj7 (Mon Jul 19, 2021 11:39 pm) • Durero (Sun Jul 18, 2021 12:39 pm) • rlrhett (Sun Jul 18, 2021 12:19 pm) • Michaeldc (Sat Jul 17, 2021 9:27 pm)
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PostPosted: Sun Jul 18, 2021 11:14 am 
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Koa
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kfish wrote:
I love this bender Dan Koentopp uses.
https://www.youtube.com/watch?v=HQMgt_kkMA0

Kent


Genius!!

I’ve been chewing on this since you posted it. Granted he’s bending 2-1/2” maple side (easy), but it seems like it should work with a 4-3/4” dread side. One may have to up the weight a little.

Thanks for sharing! M


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PostPosted: Sun Jul 18, 2021 11:41 am 
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Michaeldc wrote:
kfish wrote:
I love this bender Dan Koentopp uses.
https://www.youtube.com/watch?v=HQMgt_kkMA0

Kent


Genius!!

I’ve been chewing on this since you posted it. Granted he’s bending 2-1/2” maple side (easy), but it seems like it should work with a 4-3/4” dread side. One may have to up the weight a little.

Thanks for sharing! M


I asked him about how long it takes to bend and he said about 10 minutes to complete the bend and then he cooks it for 15 minutes. I was thinking that was a cinderblock for a weight which should be plenty but on second look I guess it's not. So yeah, maybe a little more weight, though he does a lot of different woods in his builds. I don't know if he varies the weight.


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PostPosted: Sun Jul 18, 2021 11:44 am 
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Koa
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kfish wrote:
Michaeldc wrote:
kfish wrote:
I love this bender Dan Koentopp uses.
https://www.youtube.com/watch?v=HQMgt_kkMA0

Kent


Genius!!

I’ve been chewing on this since you posted it. Granted he’s bending 2-1/2” maple side (easy), but it seems like it should work with a 4-3/4” dread side. One may have to up the weight a little.

Thanks for sharing! M


I asked him about how long it takes to bend and he said about 10 minutes to complete the bend and then he cooks it for 15 minutes. I was thinking that was a cinderblock for a weight which should be plenty but on second look I guess it's not. So yeah, maybe a little more weight, though he does a lot of different woods in his builds. I don't know if he varies the weight.


He’s got an earlier YouTube vid from before he added the half cinderblock. The weight makes it look so easy


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PostPosted: Sun Jul 18, 2021 12:20 pm 
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kfish wrote:
I love this bender Dan Koentopp uses.
https://www.youtube.com/watch?v=HQMgt_kkMA0

Kent

Wow! Now that’s what I’m talking about. So ingenious!

I’m going to have to study that video a lot to fully understand that jig.


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PostPosted: Sun Jul 18, 2021 4:04 pm 
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Cocobolo
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The thing is with bending cutaways is that you have this double - Z - bend if you like. And what you have to do is to support the wood on the outside of both of those curves. To do this you have to tension both steel slats I have constructed an admittedly rather crude device to do this. It is not my idea. I think it was Mike Doolin who first suggested this in an early Gal and others have developed the idea.

The trick is that the slats and the sides are fixed at the tail end and springs are used to tension the slats both above and below the side wood to provide support on the outside of the two bends. I always do cutaways - fairly sharp - and this has worked with few failures for me.

Hopefully the pics show the general idea. Cheers Dave


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These users thanked the author Dave m2 for the post (total 4): James Orr (Tue Jul 20, 2021 10:29 am) • Pmaj7 (Mon Jul 19, 2021 3:27 am) • rlrhett (Sun Jul 18, 2021 5:01 pm) • CarlD (Sun Jul 18, 2021 4:49 pm)
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PostPosted: Mon Jul 19, 2021 9:52 am 
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Based on something I think I saw here I made an extension with a pulley and instead of springs ran a cord from the slats over the pulley and put on about 5lbs to tension the sandwich.

Thought I had an in action picture but can’t find it. It has worked well.

One nice thing about double sides and a tight cutaway is you can bend both together but with a much thinner thickness.

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PostPosted: Tue Jul 20, 2021 5:30 pm 
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Terence that is another way to do it but although I haven’t measured it I suspect the springs I use are probably exerting rather more force. You are presumably bending pretty thin stuff if you are building double sides.

Rather poor pics but I move the anchor points for the springs forwards as the bend is formed to keep the tension from becoming too great. I guess a weight on a pulley has the same effect.

I am working with about 1.8 mm for the cutaway sides - a bit more for the non cutaway. And I do do a pretty sharp cutaway.

Out of interest how are glueing the two laminates?

Dave



These users thanked the author Dave m2 for the post: Terence Kennedy (Wed Jul 21, 2021 9:03 am)
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PostPosted: Wed Jul 21, 2021 1:16 pm 
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Brazilian Rosewood
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Unibond 800 Dave. It’s worked great for me. Clamped over an inside form with shaped cauls. It also serves as the bending form.

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PostPosted: Thu Jul 22, 2021 10:48 am 
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Cocobolo
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Thanks Terence. Laminated sides is something I am likely to try at some point.


Dave


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PostPosted: Sat Jul 24, 2021 4:33 pm 
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KFish,
That is the coolest, most versatile bender I have ever seen. I would love to know what he uses for a friction clutch. I don't notice him tightening anything as he goes.
Well done.

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