Official Luthiers Forum!

Owned and operated by Lance Kragenbrink
It is currently Mon Nov 25, 2024 4:48 am


All times are UTC - 5 hours


Forum rules


Be nice, no cussin and enjoy!




Post new topic Reply to topic  [ 14 posts ] 
Author Message
PostPosted: Tue Dec 14, 2021 7:06 am 
Offline
Contributing Member
Contributing Member
User avatar

Joined: Wed Oct 08, 2008 11:36 am
Posts: 7376
Location: Southeast US
City: Lenoir City
State: TN
Zip/Postal Code: 37772
Country: US
Focus: Repair
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.

_________________
Steve Smith
"Music is what feelings sound like"


Top
 Profile  
 
PostPosted: Tue Dec 14, 2021 8:00 am 
Offline
Contributing Member
Contributing Member
User avatar

Joined: Fri Jul 10, 2009 4:44 am
Posts: 5493
First name: colin
Last Name: north
Country: Scotland.
Focus: Build
Status: Semi-pro
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.

_________________
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)
Top
 Profile  
 
PostPosted: Tue Dec 14, 2021 8:16 am 
Offline
Contributing Member
Contributing Member
User avatar

Joined: Wed Oct 08, 2008 11:36 am
Posts: 7376
Location: Southeast US
City: Lenoir City
State: TN
Zip/Postal Code: 37772
Country: US
Focus: Repair
That's a great link Colin, thanks! I had forgotten about that build thread.

_________________
Steve Smith
"Music is what feelings sound like"


Top
 Profile  
 
PostPosted: Tue Dec 14, 2021 12:32 pm 
Offline
Contributing Member
Contributing Member
User avatar

Joined: Sat May 17, 2008 1:11 pm
Posts: 2373
Location: Spokane, Washington
First name: Pat
Last Name: Foster
Country: USA
Focus: Build
Here's another one.

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

_________________
formerly known around here as burbank
_________________

http://www.patfosterguitars.com



These users thanked the author Pat Foster for the post: SteveSmith (Tue Dec 14, 2021 2:03 pm)
Top
 Profile  
 
PostPosted: Tue Dec 14, 2021 2:06 pm 
Offline
Contributing Member
Contributing Member
User avatar

Joined: Wed Oct 08, 2008 11:36 am
Posts: 7376
Location: Southeast US
City: Lenoir City
State: TN
Zip/Postal Code: 37772
Country: US
Focus: Repair
Thanks Pat, I appreciate the photos that show the steps taken to put in the backing for the scoop. Makes sense.

_________________
Steve Smith
"Music is what feelings sound like"


Top
 Profile  
 
PostPosted: Tue Dec 14, 2021 3:28 pm 
Offline
Brazilian Rosewood
Brazilian Rosewood

Joined: Sat Jan 15, 2005 12:50 pm
Posts: 3927
Location: United States
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.


You do not have the required permissions to view the files attached to this post.


Top
 Profile  
 
PostPosted: Tue Dec 14, 2021 3:51 pm 
Offline
Brazilian Rosewood
Brazilian Rosewood

Joined: Sat Jan 15, 2005 12:50 pm
Posts: 3927
Location: United States
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.


You do not have the required permissions to view the files attached to this post.


Top
 Profile  
 
PostPosted: Tue Dec 14, 2021 3:56 pm 
Offline
Brazilian Rosewood
Brazilian Rosewood

Joined: Sat Jan 15, 2005 12:50 pm
Posts: 3927
Location: United States
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.


You do not have the required permissions to view the files attached to this post.


Top
 Profile  
 
PostPosted: Tue Dec 14, 2021 4:04 pm 
Offline
Brazilian Rosewood
Brazilian Rosewood

Joined: Sat Jan 15, 2005 12:50 pm
Posts: 3927
Location: United States
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.


You do not have the required permissions to view the files attached to this post.



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)
Top
 Profile  
 
PostPosted: Tue Dec 14, 2021 4:14 pm 
Offline
Contributing Member
Contributing Member
User avatar

Joined: Wed Oct 08, 2008 11:36 am
Posts: 7376
Location: Southeast US
City: Lenoir City
State: TN
Zip/Postal Code: 37772
Country: US
Focus: Repair
That is very nicely done Alan. Thanks for posting that.

_________________
Steve Smith
"Music is what feelings sound like"


Top
 Profile  
 
PostPosted: Tue Dec 14, 2021 6:48 pm 
Offline
Koa
Koa

Joined: Mon Dec 18, 2006 9:42 am
Posts: 1577
Location: United States
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)
Top
 Profile  
 
PostPosted: Wed Dec 15, 2021 3:13 pm 
Offline
Brazilian Rosewood
Brazilian Rosewood

Joined: Sat Jan 15, 2005 12:50 pm
Posts: 3927
Location: United States
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.


Top
 Profile  
 
PostPosted: Wed Dec 15, 2021 5:32 pm 
Offline
Contributing Member
Contributing Member
User avatar

Joined: Wed Oct 08, 2008 11:36 am
Posts: 7376
Location: Southeast US
City: Lenoir City
State: TN
Zip/Postal Code: 37772
Country: US
Focus: Repair
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.

_________________
Steve Smith
"Music is what feelings sound like"


Top
 Profile  
 
PostPosted: Thu Dec 16, 2021 4:24 pm 
Offline
Contributing Member
Contributing Member
User avatar

Joined: Sat May 17, 2008 1:11 pm
Posts: 2373
Location: Spokane, Washington
First name: Pat
Last Name: Foster
Country: USA
Focus: Build
Of all the bevel cutaways, Alan, yours takes the cake!

_________________
formerly known around here as burbank
_________________

http://www.patfosterguitars.com


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 14 posts ] 

All times are UTC - 5 hours


Who is online

Users browsing this forum: No registered users and 58 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  
Powered by phpBB® Forum Software © phpBB Group
phpBB customization services by 2by2host.com