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One of the commissions I picked up at Healdsburg. My client had a piece of wood he really wanted to work into the guitar somehow, so we decided on a three piece back. I haven't done one in many years and am really pleased with the look. It's ziricote with a bocote wedge. It'll have bocote bindings as well.

It's one way to take advantage of some really nice woods that may be available in smaller sizes and often times results in a really pleasing look. I used a thin piece of ebony between the woods to provide a little bit of transition from the ziricote to the bocote.

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Jimmy Caldwell
http://www.caldwellguitars.com

jimmy on that laminated arched waist brace do you bend the two halves then sandwich the cf or laminate it flat then bend. I assume you laminate flat then bend. very interesting bracing

Michael,

I built a very simple jig out of plywood that has the outer radius of the brace fixed on the base and the inner radius of the curve is wedged against the brace with wooden wedges. It's all glued up at once. No prebending is necessary as the brace is formed from .02 thick maple veneers. I put them in the jig, flood with CA, and insert the wedges.

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Jimmy Caldwell
http://www.caldwellguitars.com

Beautiful, Jimmy. What's the theory behind the arched brace?

Bruce,

It's the speaker cone theory. The curved brace completes the circle of the lower bout and the radial braces allow the back to vibrate from the center out. It's like any other theory, hard to prove, but I've done quite a few like this, and I'm happy with the results.

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Jimmy Caldwell
http://www.caldwellguitars.com

Jimmy, your innovative building skills never cease to inspire me. I love people that think outside the envelope, more power to you.

Colin

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

Beautiful looking guitar. Inspires me to be more open minded about change. (something the wife has been trying to do for years,)

Very nice and neat looking - ever thought about making it a hair bigger in radius, then scalloping the ends and tucking it under the lining ??? How tall is the curved brace, and the large crossgrain one as well - looks about 3/4 or 7/8 inch ???

Just curious, it probably hasnt happened before, but with the brace ends so large and untucked, do you think a sharp blow might knock the curved brace loose ???

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

[QUOTE=Colin S] Jimmy, your innovative building skills never cease to inspire me. I love people that think outside the envelope, more power to you.

Colin[/QUOTE]

Uh, don't you mean... Outside the speaker cone?

Er... sorry, I couldn't resist.

Steve Brown

Tony,

Dimensions on the braces are:

upper curved brace 1" tall .022 thick
lower transverse brace 7/8" tall .024 thick
radial braces 3/4" tapering to zero .024 thick

I've considered doing as you describe with the upper brace, but have decided not to. The intent is to restrict movement in the lower bout, but not to eliminate it from the upper bout. I've not had any problems with the brace coming loose. I tend to avoid tucking braces as a rule on both tops and backs, as I feel they restrict plate movement. By the way, the radius on the curved brace is exactly the same as the lower bout. I simply locate the brace inside the imaginary circle of the lower bout and that's why it looks smaller.

Thanks for your comments. I really admire your work.

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Jimmy Caldwell
http://www.caldwellguitars.com

Hi Jimmy .. are you sure you mean 22 and 24 thou ??? Or 220 and 240 (ie less than 1/4 inch) ??? I wouldnt think 22 thou is very easy to keep glued on - no surface area at all !!!

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

I just like really thin braces.

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Jimmy Caldwell
http://www.caldwellguitars.com