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Colin,

Nice parabolic shaping! I'm sincerely flattered, in an imitationally sort of way, to completely fracture a familiar metaphor...

IMHO, the braces are too heavy, but it will still sound great. NTYA, but I would offer for consideration, if it's not already buttoned up, chiselling the ends of the braces butting the X down to close to zero, and reshaping enough of the brace to flow that in with the rest. Try tapping over the X at the junction points, and then over the areas in between. I think you'll find a clearer ring tone with more sustain in between, and a thud over the junctions.

Should you try this, you will find the difference tapping the X along its length will disappear. I recall that Hesh reported doing the same suggestion on his recent top, and that it opened up some. That would apply also to both ends of that short brace between the upper belly brace/tone bar and the leg of the X.

Nice careful work. Are you in cahoots with the head dude at Da Foite Guitars? His work is looking very good, too. Another early disciple, along with Greg. Hi guys.

Scott

Scott,

I think that some people use the X in the lower bout or two seperate X's as they find they can tune the back better that way (I seem to remember Alan Carruth saying he had tried the one like I do but moved to the lower bout X for this reason). My main reason for switching to X braced backs was similar to Colin's - I wanted the front to back arching to come from the bracing rather than the side shaping and forcing it into this shape when gluing. I first did this on a guitar-bouzouki I made and loved the - what seemed to my ears anyway - extra "projection" that resulted.

I also like the way the X and ladder braces lock. On my tops I have a very narrow X brace angle (78 degrees) and have the upper bout X arms locked into the upper bout brace. This upper bout brace is the last brace I put on the top and I never cease to be amazed at how much the top becomes more "alive" and responsive when this brace goes on. I am more and more convinced as I build that the upper bout is an "active zone" and needs to be freed up to play its full part. That's whay I have moved to the CF butress braces and free-floating adjustable necks.

The back X centre point is much further forward than on the top and if you look at the picture I posted is almost dividing the back into upper and lower bout sections.

_________________
Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

X braced backs really do look cool, and that's at least half the sound...

I don't expect anyone to simply follow what I am doing. It's just nice to have the chance to spread a few more wild oats and see what might come up...

And if you learn anything from unbridled, wanton parabolas, it's nice to be able to offer something in return for the wisdom found here.

Dang, these little round thingies are habit forming...

Scott

[QUOTE=Scott van Linge] Colin,

Nice parabolic shaping! I'm sincerely flattered, in an imitationally sort of way, to completely fracture a familiar metaphor...

IMHO, the braces are too heavy, but it will still sound great. NTYA, but I would offer for consideration, if it's not already buttoned up, chiselling the ends of the braces butting the X down to close to zero, and reshaping enough of the brace to flow that in with the rest. Try tapping over the X at the junction points, and then over the areas in between. I think you'll find a clearer ring tone with more sustain in between, and a thud over the junctions.

Should you try this, you will find the difference tapping the X along its length will disappear. I recall that Hesh reported doing the same suggestion on his recent top, and that it opened up some. That would apply also to both ends of that short brace between the upper belly brace/tone bar and the leg of the X.

Nice careful work. Are you in cahoots with the head dude at Da Foite Guitars? His work is looking very good, too. Another early disciple, along with Greg. Hi guys.

Scott



[/QUOTE]

Scott, glad you approve of the braces, even with your reservations! I'm afraid though that they can't be claimed as imitational, I having been shaping my braces in this way for a number of years now. As I said "parabolic" brace shapes are very popular this side of the Atlantic and have been the subject of much discussion and evolution for a long time. They tend to suit the styles of play popular here. We are not so heavily influenced by the Martin scalloping and have tended to plough our own furrow. My own patterns are the result of discusssion with a number of the leading UK builders, over a lot of beer.

I have made about 20 using these principles and now have them just as I like them. This top has been tuned as I like it, and no, there are no dull spots over the brace junctions, this is something I am very careful to ensure when brace shaping, so I shall be leaving them as they are. I tend to start with only the best Euro for the top and braces and usually end up with a top in the .090-.100" range which will be further tuned after it is fitted to the sides.

As I said I greatly respect your work, but don't necessarily accept the basis of it all. My professional work on the transmission of waveforms through both homogeneous and non-homogeneous materials leads me to different conclusions to yours. I am always conscious of the fact that in guitar and lute building we are dealing with a number of non-homogeneous materials and each piece of wood has to be treated on its own merits and can't be shoehorned into any particular mathematical shape.

Dave and I tend to follow similar principles in our building, though I'm more influenced by the work of George Lowden and Dave by that of Stefan Sobell, but we both build for a more "British style" as does Russell Rose another of our comrades here.

Good to have you here on the forum though, I enjoy your input, always thought prevoking.

ColinColin S39042.6493518519

_________________
I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

Colin,


Apologies all around. I shouldn't have presumed about Dave or you. He did send me photos last winter of a top he was building for critiquing, and I see his current work seems to reflect some of my ideas, and has become very clean and gracefully parabolic.

I don't claim to have invented the parabola, nor parabolic bracing. However, I've never seen reference to it in literature before my first article in the Fall, 1996 issue of "American Lutherie." But there's lots I haven't seen.

As I've said elsewhere, Martin used many of the same shapes as do I, and I saw pictures of an early '30s Regal in the Spring 2006 issue of "American Lutherie" showing parabolic back braces.

BTW, when you get time to peer inside of your vintage Martin retirement funds, I would appreciate your feedback on the questions I raised in an earlier post on this thread. Since I've only seen inside of three, myself, your observations would double the bandwidth.

As Yank Rachell said:

"Every morning at 8, you can hear me tappin' that thing."

Scott