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I'd like your comments, suggestions, and critique on my #2 bracing. I was too shy to ask on #1 and it was over braced. Sooo, I thought I'd go out on a thin limb for #2. This is a 000 with mahogany B/S. Thanks! Tony

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Tony Flippo

What sort of dimensions are you working from?

1/2" brace height or 5/8" or 3/4"?

What sort of top you got -- stiff/dense or soft/light? What sort of top thickness you got?

Thanks

John

You have scalloped much from the area that you need the most strength. Where the bridge is , you have the most stress and you have removed too much material. I am afraid you will have too much rotation.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Flippo,
With out feeling the stiffness of the top and bracewood before and after voicing the top, there is no way of telling.
If only going by pictures, my bracing is generally smaller than what you show. The peaks of the lower X braces usually falls about 3" in from the outer perimeter of the sides on my tops, then I feather them down to nothing just short of the sides, they are free and not tucked. Same with the finger braces. I only tuck the upper X and transverse brace.
I also have a tendency to make my tone bars not run parallel with each other, I try to point the lower one more toward the open area of the lower bout in an attempt to channel the string/bridge energy to that area.
I have often thought about running the lower tone bar off the upper tone bar like a letter T into that area.
It seems with the standard X brace pattern that area below the lower bar lost opportunity.

Excellent workmanship by the way!

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John, The top is Sitka Spruce 1/8" thick. It seems soft and light, but I am a newbie. The brace plans call for 5/16" wide by 5/8" tall. My braces are very close to that - maybe a hair higher. thx, Tony

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Tony Flippo

Well, it is awfully pretty!

So hard to tell things from pictures, especially deflection. My gut says "if it looks good, it is good" and my gut feels pretty good, but I keep staring at how little height is left in the middle of the brace.

What are you gonna do though? Build her, I say!

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Not a scallop brace guy, so I wont comment there .. but ...

I would not leave a bridge plate with the sharp, full thickness corners like you have - over time, when the bridge starts to pull some, those points will telegraph right thru the top. My bridge plate goes straight into the side of the X brace .. no corners.

In your case, seeing as its already glued on .... chisel them off to nothing.

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

Do you have pics of #1 top?

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Do any of you wonder if that big square patch splice at the X is going to effect the voice? It seems to me that when I shaved the intersection down just a bit it made a change. To me it looks like something that would dampen vibrations. But I'm still waiting on the Somogyi books and Alan's DVD.

If any of you saw the Somogyi videos taken a couple years back, he mentions that Judy Threet did some experimenting and that the X cap need only be about 1/64th thick - I use about 1/16th ... you really only need to get the brace with its notch up capped - adding a fulll square like that means you have effectively stiffened that area a whole bunch (every one percent of added height adds three percent of stiffness approx) -and its likely not needed.

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

What gauge strings are you planning to use?

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Formerly known as Adaboy.......

I am thinking the 1/8" top thickness is pretty hefty.... unless that is some *Really* soft sitka... you may not have anything to worry about.

You may end up thinning out the top at the lower bout some once you get it glued to the box.

On capping the X-- I think Chris is right here. I have used either 1/64" birch plywood or 2 crossing veneer strips, then cut to match the X.

On my last guitar.. I glued the top to the body before gluing on the back.
Then I tapped and tapped all over the lower bout.. and shaved braces a little here and there till the tapping sounds were basically the same all over down there.

I had some scallops -- but during bonking and shaving, I ended up trimming down the peaks by the rims until they were just a wee bit taller than the shortest portion (<1/8" taller)

It came out sounding *Very* nice... I don't know if this is what caused it to sound good... but I think it is probably on the list of things that helped.

Good luck

John

Darryl, Light Gauge D'Addario EXP16

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Tony Flippo

John, The plan calls for 5/16" hieght at this area. Mine is right at 5/16". Is this too low? Thx, Tony

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Tony Flippo

Tony,

I am no substitute for John's knowledge so hopefully he will give his feedback. John may be referring to the sharp drop off in height of the X-brace just behind the intersection. It would add a lot of strength if the height were tappered down more gradually......though someone with more experience will need to advise you on what is optimum. Using lighter strings will help.

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Formerly known as Adaboy.......

I was out at Nazfest and just got home. What I was trying to point out is that you have taken a good bit of support away from the area you need it most. At the point of the bridge plate you have the most stress. Not only do you have the pull of the strings you also have the rotational force. This is magnified by string height and gauge. The plate will help but don't rely solely on the plate to control this force.
I made a similar mistake on my #2, that is now ashes. I couldn't keep the top from over rotating and lost control of maintaining proper action height. You will learn more from a failure than you will from a success.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I'm no expert but the "bridge doctor" is supposed to correct over-rotation of the bridge, and is supposedly used by Breedlove so the can brace their guitars more lightly. So that might be an option here.

http://www.stewmac.com/shop/Tools/Speci ... octor.html

Joe

John, I think you are right. I will learn more from my failures that any great success on #2. After staring at this and reading much about bracing, I'm going to close the box. This guitar is staying in the house anyway, and I will learn if/when something happens (after documenting of course).

I want to thank all for the constructive critique. I know it is hard to give a really good answer when you just have a picture to look at. I know I have learn much from this.

Thx, Tony

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Tony Flippo