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Does anyone do this...upper transversal
http://www-.luthiersforum.com/forum/viewtopic.php?f=10102&t=9276		 Page 1 of 1
Author:  Andy Zimmerman [ Sun Nov 12, 2006 9:37 am ]
Post subject: 
Awhile back I switched to a dual tenon fully bolt on neck design (Mayes/
Bourgois etc).
I don't use the flat popsicle brace because of the fretboard extension on
the neck block.
Lately I have been asymetrically carving my upper
transverse brace. Meaning the soundhole side is rounded over to keep
the strength but minimize weight. (Like all of our braces)
Well on the neck side of the upper transversal, I keep it dead flat and at
90 degrees from the soundboard. This allow me to butt my fretboard
extension block on my neck right up to it. The upper transverse gets
glued to the neck block (fretboard extension) when gluing the top on. My
theory is that from the neck block to the upper transversal is solid. A
solid T shape. Also I tuck my upper in the kerfing. I am guessing this will
minimize changes over time.
Am I overdoing it? Is this overkill?








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Author:  Alain Desforges [ Sun Nov 12, 2006 9:46 am ]
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Andy, funny you should post this thread, I was just pondering the exact same treatment under the fretboard...

A solid block sure would negate any movement, it seems. I imagine the trick would be to find a proper balance between weight and stiffness...

Author:  Andy Zimmerman [ Sun Nov 12, 2006 10:03 am ]
Post subject: 
Alain. Personally I would substitute strength for weight in certain parts of
the guitar. (I don't know if this is correct) A lot of my fretboard extension
block get removed cutting the mortice for the fretboard tenon.

below is a pict of customer with his guitar. You can see the cutout


Author:  JBreault [ Sun Nov 12, 2006 10:37 am ]
Post subject: 
Andy, this looks very strong. I'm sure it would guarantee that the fretboard extension NEVER pushes into the sound hole.
Author:  Andy Zimmerman [ Sun Nov 12, 2006 11:23 am ]
Post subject: 
Hesh
This idea was based on something I saw on one of John Mayes videos.
He stated that if the fretboard extension doesn't touch the brace then shim
it to make contact.
I would love for him to chime in
Author:  SteveCourtright [ Sun Nov 12, 2006 11:31 am ]
Post subject: 
Andy,
This is very similar to the D1 (A-Braced) Martin style.


Author:  JJ Donohue [ Sun Nov 12, 2006 12:56 pm ]
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Nice clean work, Andy...I like the idea and I like your execution. Do your threaded inserts reach into the FB or just the tenon?
Author:  CarltonM [ Sun Nov 12, 2006 1:10 pm ]
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[QUOTE=Hesh1956] I am thinking and have been thinking for some time now that there is tone potential in the upper bout that some bracing and neck block designs may deaden. [/QUOTE]
My underexperienced brain tends to agree, but Alan Carruth has said that it's the air volume of the upper bout that's likely to contribute the most to sound potential--hence the wimpy tone when substantial portions of the upper bout are removed. However, I believe he has acknowledged that some folks have gotten tone improvements by removing or modifying that little "popsicle" brace. Others have indeed testified to that. I guess the mystery continues...
Author:  Andy Zimmerman [ Sun Nov 12, 2006 3:10 pm ]
Post subject: 
JJ
They only go into the tenon. I use a T nut in the tenon that gets recessed azimmer139033.9663888889
Author:  Alan Carruth [ Mon Nov 13, 2006 1:09 pm ]
Post subject: 
I have found it difficult to get really solid contact between the neck extension and the shoulder brace reliably. Hence I've been using an inletted "A" brace similar to Steve Courtwright's for about ten years. It works: I've had folks come back with seriously dropped guitars, with big dings in the neck but no failure of the top along the fingerboard extension.

I can't say of my own experience whether removing the 'popsicle stick' brace improves the tone or not. I don't think it does much structurally, particularly since the big manufacturers using it have stopped using hide glue and switched to things that can cold creep. I can see that it _could_ alter the tone a little bit in the very high frequency range, but whether that would be an _improvement_ is a matter of opinion.

With the fingerboard glued down, and some pretty hefty bracing in the area for structural reasons, the upper bout area of the top can't really do much in the low to mid range. Alter any of those 'givens' and it's a new ball game. Most of us stick with the 'tried and true' here, simply because the forces are rather high for such a light structure, and who wants the risk?

The air mass in the upper bout does have an effect on the tone, so it's worth keeping the 'traditional' shape even if the top is totally imobilized in that area, IMO. Yes, there are some folks who make guitars that people like having no upper bout to speak of. I'm not sure how they do it, never having measured any of them. Some time.....
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