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PostPosted: Tue Dec 14, 2021 7:06 am 
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Guess they’re called scooped or beveled cutaways. Would like to do one on the nylon crossover build I’m starting. Would appreciate photos (or links to info) of completed scooped cutaways and any shots showing how they were made. I’m thinking I could do it using a technique similar to an Everett arm bevel with veneer. Thanks.

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PostPosted: Tue Dec 14, 2021 8:00 am 
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I think I remember, ah yes, Burton LeGeyt, is this what you're after? - http://www.luthiersforum.com/forum/viewtopic.php?f=10117&t=29270&p=418109&hilit=cutaway#p418109
Does that help, haven't got time to do a full read.

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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.



These users thanked the author Colin North for the post: SteveSmith (Tue Dec 14, 2021 8:17 am)
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PostPosted: Tue Dec 14, 2021 8:16 am 
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That's a great link Colin, thanks! I had forgotten about that build thread.

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PostPosted: Tue Dec 14, 2021 12:32 pm 
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Here's another one.

http://www.patfosterguitars.com/opus/index.html

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These users thanked the author Pat Foster for the post: SteveSmith (Tue Dec 14, 2021 2:03 pm)
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PostPosted: Tue Dec 14, 2021 2:06 pm 
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Thanks Pat, I appreciate the photos that show the steps taken to put in the backing for the scoop. Makes sense.

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PostPosted: Tue Dec 14, 2021 3:28 pm 
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I saw Burton's cutaways some years ago. I liked them, but they seemed a bit 'incomplete', so I worked out my own way to do them. I hope I can get it across.

I wanted it to be a continuation of the binding, at least to look at, and that meant including a recurve section to tie in. After a few tries here is the pattern I came up with.


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PostPosted: Tue Dec 14, 2021 3:51 pm 
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I guess I was too quick with the 'submit' button, but at least it worked.

This would be cut out of the same sort of wood as the binding, and a bit thinner than the side, since it's going to be bent to fairly tight radii. The bend is an 'S' curve, with the end of the 'tail' being bent downward, and the point to the right 'up'. The bends are cylindrical, and, as shown, at a 45 degree angle to the grain. This tends to crack in from the end on the right side, and I find that gluing paper on both surfaces helps to reduce that a lot. Here's the bent bevel being fitted to the box.


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PostPosted: Tue Dec 14, 2021 3:56 pm 
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I'm having some trouble getting more than one image per post, but I'll work on that.

The box has been assembled as far as routing the binding/purfling rabbets. The initial cut into the side and top is made with a hand saw, and dressed off using knives and files to begin with. Once the bent cutaway has been roughly matched I glue in liners on the side and top, in this case of willow about 5 mm thick, with the end grain toward the opening. The cutaway is carefully chalk fitted from there.


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PostPosted: Tue Dec 14, 2021 4:04 pm 
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The side lines are bent with the binding, and separated using a hot knife. The binding is then cut off where it butts into the cutaway, leaving the side line whole. This can then be bent in the vertical direction to fit around the lower edge of the cut.

I have yet to figure out any better way to gut the binding and purfling channels around the cutaway on top and on the side other than using a knife and small chisel. A very sharp knife, very carefully.

I hope those few shots will help folks to figure this out.


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These users thanked the author Alan Carruth for the post (total 4): Glen H (Thu Dec 16, 2021 6:42 pm) • Hesh (Wed Dec 15, 2021 3:17 pm) • Colin North (Tue Dec 14, 2021 5:32 pm) • SteveSmith (Tue Dec 14, 2021 4:12 pm)
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PostPosted: Tue Dec 14, 2021 4:14 pm 
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That is very nicely done Alan. Thanks for posting that.

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PostPosted: Tue Dec 14, 2021 6:48 pm 
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https://www.youtube.com/watch?v=gX3juuCJtrE

Marshall Brune approach



These users thanked the author wbergman for the post: SteveSmith (Tue Dec 14, 2021 8:02 pm)
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PostPosted: Wed Dec 15, 2021 3:13 pm 
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The thing that bothered me when I first saw one of the bevel cutaways was that it looked like a belt sander accident. I wanted to tie it in to the binding, and make it look as though I meant it, as my violin making teacher used to say.

With a simple scoop the exact angle doesn't matter, but with the recurve it does. As mentioned, the two bends are cylindrical, and it turns out that you really want the axes of those cylinders to line up with the center line of the guitar. Making the axis of the cut normal to the slope of the side at that point really messes up the recurve, and makes it hard to get the cutaway to line up with the binding.

I think it was Augie LoPrinzi who first incorporated ports into this form of cutaway. The original 'multi-dimensional sound port' was made as a belt sander scoop. It's certainly an effective port, in terms of altering the sound of the guitar. However, it doesn't make such a good monitor for the player, particularly if you've only got one on the treble side, as Brune does.


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PostPosted: Wed Dec 15, 2021 5:32 pm 
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Not sure about scoops with ports. Guess they can be a "feature" but doesn't make sense to me either to put them on the treble side. I'll stick with my ports on the bass side upper bout for the player.

Alan, I like the way your scoop blends into the binding; I was toying with something similar but thinking I might try to incorporate some of Kent Everett's armrest construction ideas - at the moment I have no idea if it will work. I might have to wait for another guitar if I want to use the same wood as the side. Lots to think about here.

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PostPosted: Thu Dec 16, 2021 4:24 pm 
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Of all the bevel cutaways, Alan, yours takes the cake!

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