Page 1 of 2

Cutaway "pocket" building tips

Posted: Fri May 25, 2012 2:02 pm
by George Dunham
I am considering building a OM with a cutaway pocket. I am not sure if I am calling it by it's correct name but it appears to me to be a nifty little pocket built into the treble side at the neck. Built by carving into a solid block on the treble side of the upper bout, creating a space for the left hand above the 14th fret. It looks simple but it also looks like the binding and "laminate" might be a bit tricky. An example I can recall is by "Valley Guitars". Can anyone give me direction on this.
I am considering this because I am reluctant to do the cutaway bend for the more traditional cutaway.

Re: Cutaway "pocket" building tips

Posted: Fri May 25, 2012 2:19 pm
by Alan Carruth
I've seen this called a 'bevel cutaway. There are a couple of ways to do it. Some folks start with a large solid block, and just carve it out. Most of the ones I've seen bend a piece, and fit it into cutouts in the side and top. I've been making a refinement of this for a while now; bending the cutaway piece into an 'S' curve, so that it blends into the binding on the side as a 'soft' cutaway, rather than coming to a point. Maybe I can post a picture of this later.

Aside from looking sexy, I like this style of cutaway because you don't risk breaking a side that might be hard to replace. It gives all the access you need, and eats out less air volume in the box, which may not mater much, but then again..

The big problem with it is the time it takes to fit the cutaway piece, and to do the purfling. I have not been able to figure out any way around hand cutting the purfling in with a sharp knife after purtting in the cutaway itself. You might be able to do the purfling first, but it's still hard to see how you could cut the rabbet with a router or anything like that.

Alan Carruth / Luthier

Re: Cutaway "pocket" building tips

Posted: Fri May 25, 2012 4:05 pm
by Chuck Tweedy
Alan, you will need to post a picture - I'm not getting the mental image of what you are talking about.
And, yes maybe it is just my weak mind, but hey - it is Friday.

Re: Cutaway "pocket" building tips

Posted: Fri May 25, 2012 4:15 pm
by Bryan Bear
I'd like to see a picture too. I remember you posting one on the old forum and it blew me away!

Re: Cutaway "pocket" building tips

Posted: Fri May 25, 2012 4:24 pm
by Dave Stewart
Is this the Burton LeGeyt cutaway?? (That's not the name but he's the first I remember doing it.) He did a documented build on OLF showing how. (Alan, it looks, from the pictures, like he does the top purfling before cutting).
http://www.luthiersforum.com/forum/view ... &start=100

Re: Cutaway "pocket" building tips

Posted: Fri May 25, 2012 4:30 pm
by Ian Chisholm
I think I know this as the Benjamin Scoop, you'll find a page about it and pictures on Nick Benjamin's web site.

Re: Cutaway "pocket" building tips

Posted: Fri May 25, 2012 4:59 pm
by Bob Matthews
Nick's site is here http://www.benjaminguitars.co.uk/cutaways.htm with pictures of his cutaway.

Bob

Re: Cutaway "pocket" building tips

Posted: Fri May 25, 2012 6:01 pm
by Chuck Tweedy
That is what I thought, but somehow I didn't get it. I've seen it before.

Re: Cutaway "pocket" building tips

Posted: Fri May 25, 2012 9:59 pm
by Alan Carruth
Here's a picture of one I'm working on now. The binding butts into the cutaway with an angled surface. I've stripped the side purfling loose from the binding and bent it around to follow the edge of the cutaway.

There was a tread on another group a while ago debating precedence on this feature: every time somebody made a claim for it an earlier example was cited. This is pretty common in lutherie: not to take away from anybody's originality, but it often seems to be the case that several folks come up with an idea at about the same time. Somebody was certainly the first, but it's difficult to say who: we all know about fanned frets, and the 'Manzer wedge' was patented by Smith in 1969 or so. I will say that I have not seen any _recurved_ bevel cutaways before mine, but that doesn't mean there were not any.

Alan Carruth / Luthier

Re: Cutaway "pocket" building tips

Posted: Mon May 28, 2012 1:02 pm
by George Dunham
Thanks for the info. Questions remain for me about the fabrication of the inside block (shaping vs weight) and the sequence of everything in the build. Looks like fabricating some kind of mock up would be the way to go. Hmmm...gona have to think about this. ;)

Re: Cutaway "pocket" building tips

Posted: Mon May 28, 2012 1:04 pm
by Chuck Tweedy
That is a very nice looking instrument there Alan. The binding itself is a work of art.
Thanks for sharing.

Re: Cutaway "pocket" building tips

Posted: Tue May 29, 2012 1:56 pm
by Alan Carruth
The reinforcement inside is pretty easy. The cutaway extends into the neck block, which is trimmed to fit. For the side I use a piece of willow about 5mm thick (you could make wide kerfed material), and bend it to fit the shape of the side, with the grain of the reinforcement running across the side. When I've got the cutaway piece ore or less fitted into the cut in the side and top, I put the willow piece in and trace the shape of the cutout on it. I then trim it so that it extends down onto the side for a half inch or so, and up into the cut for a bit less. Once the edge that is down on the side is trimmed up neatly I glue it in. It runs all the way from the neck block to where the normal liner ends. I shape another, flat, piece of the same material similarly and glue it to the top. Then I finish trimming the hole to fit the piece I've bend to cover it. The cutaway piece is glued in with Titebond, taped in place and then clamped with a rubber rope, the same as the binding.

There are two things I've found that really help to make this work well and look right. The first is to have the axis of the cutaway parallel to the center line of the box, rather than cutting it in normal to the side. If you cut it in at an angle the recurve is really hard to fit. The other thing is to bend the cutaway piece at 45 degrees to the grain of the wood. It's a little hard to see in the picture I posted, but bending it that way gets the grain in the cutaway to line up with the plane of the top at both ends. If you're careful, you can get the grain of the binding to flow right into the cutaway. It's hard to make the joint go away in lighter woods, but on one I did in Macassar ebony I was able to glue the end of the binding down into a groove in the cutaway, and taper that away to nothing gradually. A strategic touch of ferric acetate stain to blacken a brown streak in the binding made the whole thing flow in nicely.

Alan Carruth / Luthier

Re: Cutaway "pocket" building tips

Posted: Sat Jun 23, 2012 2:11 am
by Matthew Lau
Wow.

Re: Cutaway "pocket" building tips

Posted: Sat Jun 23, 2012 11:33 am
by Mario Proulx
Two things I really like about Alan's are the contrasting wood used for the cutaway piece, and the smooth, flowing lines. Well done!

Re: Cutaway "pocket" building tips

Posted: Sat Jun 23, 2012 8:05 pm
by Seth Ellis
Alan, that is a beautiful pocket. I'm envious. It boggles my mind how you would shape the piece to fit and get the binding channel cut. It looks very advanced.

Re: Cutaway "pocket" building tips

Posted: Tue Jun 26, 2012 2:12 pm
by Chuck Morrison
While it certainly doesn't equal the beauty and grace of Alan's, there is an article in the latest GAL AL quarterly on doing this.

Re: Cutaway "pocket" building tips

Posted: Sun Nov 11, 2012 3:01 am
by John Hamlett
So....
I had a customer order a cutaway dreadnaught, and I saw that picture from Alan, so I emailed the pic to the customer. Of coarse he liked the idea, so armed with one picture from the internet(!), I put in some head-scratching time, and after a styrofoam model or two, came up with this. I'm applying sealer to the rosewood at the time of this picture, no finish yet and still some work to do to clean it up some, but here it is. Not as easy as it looks!
cut.jpg

Re: Cutaway "pocket" building tips

Posted: Sun Nov 11, 2012 1:07 pm
by Jason Rodgers
That is some fine woodwork there, Alan. Some of those bends look mighty tricky. And very nice work recreating the feature, John, from a single picture.

This style of cutaway presents some interesting opportunities. Of course, as Alan mentioned, there is the savings on box volume, and also upper bout strength, but I see this area having potential as a new canvas for the builder's imagination. Continuing the side wood in the cutout maintains continuity, but the first time I saw this type of cutout I thought of a bite out of an apple: contrasting woods that match the headstock overlay or fretboard/bridge wood in keeping with a theme. Though the surface geometry is complicated, this could be a surface for inlay or an alternative location for the maker's mark. And since folks are putting additional sound ports everywhere, why not some decorative cutouts or designs that connect with the rosette or fingerboard appointments. The possibilities are endless!

Re: Cutaway "pocket" building tips

Posted: Sun Nov 11, 2012 3:50 pm
by Alan Carruth
Nice going John!

If you bend the wood for the cutaway at a 45 degree angle to the grain it will flow into the grain of the binding. OTOH, doing it the way you did makes the cut a part of the side, which is bound on both sides. As Jason says, this thing has a lot of possibilities. I would be careful about making a 'port' in it, though. It would work pretty well, but would no doubt also infringe on Thurman's 'Multidimensional Sound Port' patent.

Alan Carruth / Luthier

Re: Cutaway "pocket" building tips

Posted: Tue Nov 13, 2012 1:43 am
by Michael Lewis
You fellows are getting rather tricky with your woodwork and all the angles that need to fit together. It looks to me that a regular bent cutaway would be easier. But then . . . .