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I've done one compound cutaway and must admit it was not a lot of fun. I got it done but that twist in the side fought me the whole way. Now I'm thinking of doing another one for an upcoming 7 string classical. The first one I tried was on a Venetian cutaway. I'm thinking it might be easier on a Florentine cutaway because I could work on the cutaway part of the side separately from the rest of the side. I'm also hoping that I could get it glued up with less residual twisting forces going down the side than I had before. Does anyone have experience or opinions they can share in this regard?
Thanks,
Pat

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There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

You mean like this, where the heel tapers down to a narrow endcap and the side is twisted to form a continuous surface rather than having a corner sticking out like usual?

I haven't made one like that myself, but I always struggle to prevent twists from developing when bending sides, so I can guess how it's done The main thing to note is that the bend radius is tighter on the fingerboard edge than the heel cap edge. So by focusing heat and bending pressure on one edge at a time, you can tighten and loosen them to induce a twist. You'll need a little extra side width since you'll end up with a corner pointing up toward the fingerboard and a corresponding gap beside the heel cap. But don't make it too wide or it will be tougher to twist, and may partially un-twist when you trim it to width, due to cutting off the fibers that were most strongly bent.

This is a place where a double side really helps. The thinner material (and especially so when used with super-soft) is easier to form in the compound shape. Laminate them in a well made form and they will hold shape extremely well.

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Burton
http://www.legeytinstruments.com
Brookline, MA.

excuse me if I'm being an idiot and am thinking incorrectly, but since the side adjacent to the back has a larger radius that would mean it requires more length of material to traverse the distance to the heel...and to me this would imply you would end up with the bend pointing down not up towards the fingerboard...

Yes, that's what I mean. The picture you posted Dennis looks like a very nicely executed example. The double side idea sounds really good. Thanks for that Burton. If I did a Florentine cutaway, I could probably get away it doing a double side only for the cutaway region. I'll have to make up a mold and give it a try.
Incidentally, some time after my client had his guitar, I asked him how many people that he showed it to noticed and commented on the compound cutaway. His answer was zero. They noticed lots of other things about the guitar but not that. So there is part of me that asks why bother. My client has just asked for a cutaway and I doubt he is even aware of compound cutaways. Trouble is, I think they are very cool.

Pat

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There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

Doesn't actually help with your issue but I avoid it. Dave

Ditto. So far anyway.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Yep, that's what I usually do.
Pat

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There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

I'm about to my first and this is my thinking. Seems to take away a lot of headache.


Sent from my iPhone using Tapatalk

I agree it's really hard to bend guitar sides to be 100% vertical once the side is assembled. I have a slight twist in my pointed cutaway in my recent build too. So it's easy to create a compound cutaway if you shape the heel block to the right shape.

But binding installation will introduce more difficulties.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com