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I would like to know your thoughts on what the finger braces do? And why they are placed at and/or around the bridgeplate. Are they for structural support more than anything, or for tone or does it all work together?
I have built a few guitars and everytime I do the brace lay out I ask myself questions about there layout and how they/and where they should be.
I dont have the resources to study and learn about this from experienced builders that could clear things up on this...so I'll ask here.

Jeff

I think primarily it is for the structure of the instrument, but every brace effects the tone .

Jeff: Thinning the top on either side of the bridge near the edge of the guitar will tend to help treble.One would suppose that lightening up of the finger braces does the same thing. It will tend to let the cross dipole mode be more effective to a point. As Jody says all braces effect tone and they are all somewhat interdependent, at least in my mind.
Tom

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A person who has never made a mistake has never made anything!!!

Braces have a few jobs . Support the top for structure l , tone or anti split , The finger braces to 2 things , they are helpful to keep the top from splitting but also they help support the plate to handle the rotational force. I have seen them in so may configurations that I don't think they are very tonal .

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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

hello if you watch john mayes very through voicing dvds
you would hear their can be a big difference
in the ping on a 99% completed voiced top
after only taking the slightest shaving off the finger brace

although mabye he left those finger braces till the end
to show you how dramatic the sound can change
but to me
it looked like a decision john based on tapping and flexing that he chose
to take a little more off them
you could really hear a difference though
even through my crappy tv

Ideally they should start at the angle of your bridge against the x-braces and support the top there, against rotational forces as John Hall says. IME their role is controlling cross-grain stiffness of the top on the lower bout, they make a lot of difference tonally. I'v been using more of patch than finger braces lately, with great success.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

I consider "finger" braces a Martin invention which grew out of their initial use and development of "X" bracing.
The first "finger" braces around 1843 were actually quite long and nearly parallel with the lower legs of the "X" braces, as if Martin had simply taken the five fan brace pattern of the Spanish style gutars he was building at the time, removed the center fan (to clear the plate area for the use of a pin bridge) and extended and crossed the center fans to form the "X".
By around 1850 the finger braces had been modified to the familiar location, though at this time there was only one on the treble side only. This I think is a good indication of it's function which is stiffening the top in that area. By 1865 or so they were now on both treble and bass sides though one per side, as would be the case for the next hundred years or so on the smaller Martin models.
Later 00, 000 and of course D models incorporated two per side as is now the most common configuration.
In general they certainly help to stabilize and stiffen the top outboard of the main "X" support. In the Martin application they are carved paper thin at the side juncture and thus do not need the kerfing notched to accomodate them.

How would you guys decribe the difference between these traditional braces versus a complete 'ring' - classical style but thicker as used by Lowden amongst others - indeed I have used them on my first 2... but it has to be said primarily because I like the asthetic look it gives?

I am enjoying this thread . I like the history lesson from David Laplante , Thank you David and Laurent I like the wider brace ., That would also control the splitting in this area better .

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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 got a kick out your statement. I suspect you didn't mean that as it sounded. So I am only lightly busting your chops a bit here and partly taking you seriously. Actually there are a lot of experienced builders on this site that have contributed for years. Asking "here" is about as good as it gets. You don't have any less resources than most of us. A computer with internet access. That gives you access to mountains of information via forums, articles, etc., etc., etc., and from "experienced" builders to boot. Local libraries if you can't afford books and maybe a telephone to call luthiers and or find ones in your community. Car, bus, a friend to drive. People are here to help. I have developed friendships with several very "experienced" builders that I met on this site and have met and or spoken with quite a few others. I have gotten advise via emails, in person, telephone, books, at luthiers meetings, on an on.
So please tell me you didn't mean that.
L.

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Cut to size.....Beat to fit.....Paint to match.

Thanks for all the responses! And thanks to Laurent and David with your pictures.....David I liked your post with all the history behind it...very interesting!!
Thank you to Bluescreek!

Link..What I meant by "resources to study and learn" was that I can't pay a few thousand $$$$ to go and take a class on guitar building from an experienced luthier!
That said...I do look and read on the net, books and this forum for any info about guitar construction. I have'nt seen or read anything about what the finger braces acually do and where there placement should be and why!...Maybe I dont look in the right books or websites?
Anyway, it was just something I was curious about....I had an idea on one I'm building now and thought I would ask the question...

Thanks,
Jeff

For me the fingers are important both for structual integrity, and tone shaping. They help prevent the bridge from rolling forward too much, as well as helping prevent splits. I've done a bunch of testing, with different guitars, and a tonerite to see what areas of the top are active. With "normal" fingers, (2 per side, somewhere around the bridge at a ~90 degree angle to the X) the top isn't very active outside the X, above the bridge. I normally use 1 finger per side, off the front corner of the bridge. My angle is kinda toward the upper end of the X, but I vary the angle depending on the ratio of across the grain/along the grain stiffness on the top. With this arrangment I hear richer trebles, with being brittle, or muddy.

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I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/

Jeff, I figured that was what you meant but you have to admit it reads a bit funny. That aside you ask a great question and I am glad you brought this topic up as this has been a good thread.
L.

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Cut to size.....Beat to fit.....Paint to match.

Link,
Well i dont know if it reads abit funny or not?... might be the bourbon I was shoot'n when I posted the question! Guess I should'n "drink an post at the same time"...? lol

Thanks,
Jeff

Great thread! Woody and Laurent have given me some great ideas to think about.

Woody, is that an Osage Orange bridge plate?

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Formerly known as Adaboy.......

Way off topic, but what type of body is that Laurent?

It's my D-3, comparable to a 12fret 00. Inspired by the Chambure vihuela and early 20th century Martin/Ditson 0.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

Jeff,

I would second what Tomas said early on, regarding the demonstration on John Mayes' video. The demonstration there of sensitivity to the finger-brace final dimension is dramatic. (Nice video, John - my favorite of the set!)

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Jim Kirby
kirby@udel.edu

Yep, IME Osage Orange makes really good bridgeplates.

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I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/