Official Luthiers Forum!

Hi
Looking at my bracing and it dawned on me the grain orientation might be wrong..
Looked online and there's not much about it
Here's photos of the rough cut bracing

Photo 1 is brace stood as it will on the board
Photo 2 is bottom of brace which will be glued to board





Cheers

Usually people put the grain vertical. Parallel to the long side.

_________________
Pat

Ye thought something wasn't right.. start again?

Yes start over -- you'll want to shave the braces to more of a triangle to reduce weight without loosing strength the grain lines as mentioned, need to be perpendicular to the plates.

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Ken Cierp

http://www.kennethmichaelguitars.com/

I notice in one of your pictures it appeared as if you were having some difficulty shaping the brace...being caused by using flatsawn orientation of the grain...

after having read up on this subject, this is probably the main reason vertical grain orientation is used...

strength of wood is variable and some people's testing indicates it's a flip of the coin as to which orientation is stiffer...

strength is actually a different subject, more along the lines of wood being constantly under stress (either in an airplane or a house)...e.g. ability to take the load(s) and not break...guitars really aren't that loaded per se...e.g. needing to use flatsawn spruce for spars on an airplane is not a consideration...guitars aren't subject to repeated high G force loads that might result in failure of the spar (read shattering along a grain line) in a performance stunt aircraft. point being, in an engineering capacity, one is worried about something yielding (bending and not returning to straightness)...

anyway, carve along and enjoy they comparative ease of using vertical grain orientation

Thanks for the info Mike, that's interesting ,are they still strong enough and can I still use them?
The one in the picture was one of the last ones and the others are rough shaped with a chisel and carved well apart from a few little hang ups
Would love not to start again
Cheers

read this

I think you would be fine finishing what you have...just carve down the grain, not up (digging into it)

Thanks Mike. . Just read through it and was interesting. .looks like it probably is more to do with carving like you said than a strength thing.. I should be ok with what I've got..will take your advice on shaping with the grain direction

Thanks again

It's not so much strength or stiffness (and there is a big distinction between these terms, they should not be used interchangeably)
It's that when you have a flatsawn brace it is much more prone to splitting along the growth rings and especially at notches like the X brace intersection or at scallops.
I would not use these.

What Jeff said. +1

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Jim Watts
http://jameswattsguitars.com