Official Luthiers Forum!

Hey All
building #2 soundbox ....in between breaks from constructing #1 now
Now I just assumed that all the braces apart from the upper face and transverse... would be arched to the same radius as the X rad on the top...
Further reading in Cumpiano and Natelson, seems to reveal that MrC only radius' the X brace - and leaves the finger/tonebars as flat braces...as well as the soundhole reinforcements if Im also correct about that....
On my first guitar I just went ahead and radiused everything below the upper braces..... and upon reading the archives - there is a wid variety of styles of top bracing obviously..
I see mention from people of what braces they radius.... but no real explanation as to what they felt the advantage would be -
Im assuming its mainly strength advantage in top shrinkage,,, & perhaps some people have a feeling there is an increase in resonance....
Am I missing something else.... ??
Is this just another in a long list of simply "personal preferences"?
I realize that no bracing radius scheme is absolute, as some radius none of the braces and make amazing guitars,,,,
Just hoping someone could shed some light on why they feel radiusing top braces is especially advantageous...
Cheers
Charlie

Finger braces are so short it really does not matter. However if you are attempting to brace to a structural dome with the bracing as unloaded as possible and yet still maintain the domes shape the best possible then you will need to radius the tone bars.

That said if you leave them straight the influence of the X brace and sting tension will bow them anyway. However they will be in a loaded state even prior to being strung up and trying to flex back to straight but partially with strained by the influence of the radiused X brace.

I prefer to add the radius so that the top is neutral loading as much as possible prior to string up.

Why wouldn't you radius them anyway? It's not like it takes that long to sand them on a dish. I don't think I'd take any short cuts on the top and bracing. But that's just me.
Now some leave the UTB and the braces above the X flat. But that's because of the fretboard tongue.

The only braces I radius are the Main X braces. I like to keep the others flat. The tone bars and finger braces are tonal braces more than structural.

_________________
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