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hi all
I’ve got a nice stiff 20 year old Redwood top that I plan to use on my design project at college.
The spec is 16 inch lower bout 12 fret to body cutaway, 25.4 scale.
I’m thinking of using the Don MacRostie OOO sound hole and bracing placement 1/4W x 5/16H X brace as advised on the forum a while back.
Question - given the above spec what top thickness would you guys be aiming for? and would it be OK to use 1/4W x 5/16H X on a 16 inch LB redwood.
Its only my second build, my first is spruce so I don’t have a clue regarding Cedar or Redwood so any advice would be appreciated.
regards Geordie

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some tunes on acoustic and guitar synth.
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On a 12 fret 16" lower bout guitar I'd use 5/16" wide bracing -at least for the X- and a taller at the apex than what you describe.
I do not think anybody can answer your question without flexing your top. Usually redwood and WRC are left 10 to 15% thicker than a stiff spruce top.

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

I also think you should use 5/16w bracing because I think Cedar and Redwood do not make as strong a glue joint as Spruce no doubt as a result of weaker wood fibers. I think 1/4w would be too narrow for this wood.Not sure what you are saying about 5/16h,but think you could get yourself in trouble quickly with insufficent height on your braces.Top thickness again depends on stiffness. Also Redwood is notoriously famous for spliting from trauma that would not make a spruce top's eyes blink.Have used both Cedar and Redwood and they do make nice guitars.
Reread your question and may have gotten it wrong...! If you are saying 1/4wx5/16d for soundhole bracing only I think your OK. The first paragraph of advice is for your main bracing. Good luck and have fun.
Tom

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

1/4" x .3125 tall (5/16) bracing? For real??? way to short in my books. Heck that is almost square!!!! I would use 5/16 wide 5/8" or 3/4" tall on a medim to large body guitar. Heck I use 5/16 wide 3/4 tall on my OMs and 000s

hi all
Laurent, Tom & Michael many thanks for your suggestions, appreciated.
I arrived at those figures via the input below, at that time I thought it would be alpine spruce I would be using for this build so here are some of the replies by fellow OLF's, I am aware redwood is less robust, hence the call for help.






best regards
Geordie

_________________
some tunes on acoustic and guitar synth.
http://www.youtube.com/user/TheGeordieAdams
http://www.myspace.com/geordieadams

Geordie, on my Redwood OOO size guitar, 382mm (15") lower bout, I use my normal 6mm wide braces, with the X brace intersection at just less that 15mm, not including the cap. This has produced as good a sounding guitar across the board as I have built.

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

Collin,
thats just what I needed, data and pic's, I'll go with that bearing in mind what Laurent said re. thickness.
I take it finger and tone bars will be "OOO" standard.
many thanks and best regards
Geordie