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Lower face & finger braces
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Author:  Ken Mitchell [ Sun Mar 01, 2009 7:14 pm ]
Post subject:  Lower face & finger braces
I remember reading or being told that the end of the lower face and finger braces that meet the X-brace can (should?) be carved down to 1/16" or less (or to practically nothing). So, I've been doing this without really understanding why, and am left wondering.

I know that the shape and placement of these braces affects tone as well, but that they are designed mostly to support the top and to transfer the stress of the bridge (and string tension) out over the top and toward the rim.

So... back to he junction of these braces and the X-brace... is there a certain amount of tone/sound that is being TRANSFERED through the X-braces TO these braces (whereby it would make sense to have some amount of solid contact between them), or are they simply designed to 'cover the area' and prevent cracking/warping (thereby just needing to but up against or near the X-brace), and just nuance / distribute the tone that's being produced in the general lower bout area as the top flexes?

Thanks for any and all info on this question,
Author:  Hesh [ Sun Mar 01, 2009 7:38 pm ]
Post subject:  Re: Lower face & finger braces
Ken Mitchell wrote:

So... back to he junction of these braces and the X-brace... is there a certain amount of tone/sound that is being TRANSFERED through the X-braces TO these braces (whereby it would make sense to have some amount of solid contact between them), or are they simply designed to 'cover the area' and prevent cracking/warping (thereby just needing to but up against or near the X-brace), and just nuance / distribute the tone that's being produced in the general lower bout area as the top flexes?

Thanks for any and all info on this question,


Ken my friend now you are getting into an area where folks are going to have their own opinions and techniques for dealing with these braces.

IMHO braces DO help to transmit vibration and form a matrix of sorts that aids in this task. But mostly these braces provide support and help to stiffen the top.

The intersections of these braces with the X can be problematic again IMHO if there is too much mass where they butt together. I want to be able to hold the top in both hands in front of me with my thumbs on these intersections and flex the top a bit. So in order to accomplish this I always pare the finger braces and tone bars down to 1/16" or slightly less so that the top can flex. In addition, when I pare the intersections enough I can tap right on these intersections and the top will ring when before I pared them down the top thudded.

That's my .015 cents.... :)
Author:  Ken Mitchell [ Sun Mar 01, 2009 7:56 pm ]
Post subject:  Re: Lower face & finger braces
I've done the same thing, Hesh, pared them down below 1/16", and had the same experience with the tap tuning process. I go ahead and take mine down quite a bit, but I was wondering if I'm losing tone by going too far (sometimes down to 1/32" or so).

I'm curious as to what others will have to say on this topic.

Thanks for the penny and a half :)
Author:  Howard Klepper [ Mon Mar 02, 2009 3:02 am ]
Post subject:  Re: Lower face & finger braces
There is so much to say about bracing; I'm going to limit myself to two things:

Tone is not a fluid, and the braces are not pipes through which it flows.

There is a good practical reason for paring a brace down where it butts to another, and that is to let it flex in order to keep it from breaking loose if there is a blow to the top at that location.
Author:  JJ Donohue [ Mon Mar 02, 2009 8:44 am ]
Post subject:  Re: Lower face & finger braces
Howard Klepper wrote:
There is so much to say about bracing; I'm going to limit myself to two things:

Tone is not a fluid, and the braces are not pipes through which it flows.

There is a good practical reason for paring a brace down where it butts to another, and that is to let it flex in order to keep it from breaking loose if there is a blow to the top at that location.


Why stop at 1/16"...why not pare the end to nothing and eliminate the stress riser altogether? We do it at the opposite end...why not the X-brace end?
Author:  jordan aceto [ Mon Mar 02, 2009 8:57 am ]
Post subject:  Re: Lower face & finger braces
Like those guys said, i think it is best to pare down to nothing - or tuck the brace under the X if you want to couple them together and strengthen that area.
Author:  Ken Mitchell [ Mon Mar 02, 2009 10:32 am ]
Post subject:  Re: Lower face & finger braces
OK, then let's take the question one step further... if tone doesn't flow through the braces (thanks, Howard!), then why butt them up to the X-brace... If positioning and shape are the key elements, and not 'connectedness', is there any reason to have them touch the X-brace? Why not just leave them 1/32" or 1/16" shy, then feather them down like at the rim? It would make for cleaner, easier work, as well.

(I'm not trying to be difficult... just looking to build through a principle-based approach, and not through blind imitation).
Author:  JasonM [ Mon Mar 02, 2009 11:34 am ]
Post subject:  Re: Lower face & finger braces
Another possible consideration is that a brace end (with any height) butting up to the x-brace, even if they have been glued, could in the future have the glue bond crack, then the tiny gap could be a source of buzzing or some subtle tone contaminant. Feathering out rather than butting ends together would eliminate this possibility.
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