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Hello,
I've always liked guitars with hardwood tops. Mostly for looks, but I've also heard a few which sounded very sweet. I was wondering how you go about thicknessing and bracing a hardwood top.

If you do deflection testing, can you just use the exact same numbers that you use for softwoods for hardwood tops as well to determine the final top thickness? And can you then use pretty much the same bracing that you use on your spruce top guitars?

Or is there something completely different about hardwoods? I've read a couple of suggestions about top thickness for koa or mahagony, but I was wondering how you come figure out the thickness.

Do you use the same criteria for hardwood tops when selecting the wood as for softwood tops (light, stiff, perfectly quartered, no runout)? Is a wildly figured koa or walnut top less desirable because the figure compromises stability?

thanks, Christian

Which hardwood are you considering?

An easy answer is just treat it like spruce, same bracing & everything, but every hardwood should be considered individually, because each has it's unique qualities. Figured hardwood is usually weaker than straight grain wood. And most figure in hardwood is off quarter and even flat-sawn.
If it's a nice stiff hardwood, it can be finished a little thinner than spruce. If you have experience with deflection testing your spruce tops, similar deflections on hardwood would be good.

I'm just now finishing a all Honduras Mahogany guitar, L-00 sized, perfectly quartersawn wood, which is always a best choice for stability. Honduras is usually finished a little thinner than spruce for the top, this one is around .100" regular X braced with spruce, 1 tone bar.

Someone else chime in on Walnut for tops, I've not done one, my sense is (from doing backs and sides) is that it could be used the same as mahogany, if it were quartered, thicker if it has figure.

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Thank you David,

I'm planning to build an all-spanish cedar guitar soon. The top is nicely quartered and without figure, back and sides are rift-sawn with curl. I was asking the question in general terms as I'm also interested in walnut/koa/mahogany guitars.

I hoped that there might be a common underlying principle (like always using the same deflection) that can be applied to all tops, whether they're from softwoods or hardwoods.

best, Christian

I did a 00-sized guitar of all Spanish Cedar, a very sucessful build, wonderful tone, greatly under-utilized as a body wood. Probably because it looks "plain".

I would handle Spanish Cedar no thinner than a comparable build in Spruce.

Figured SC is very weak, I would steer clear, or handle with care.

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Great, thanks again, David.

I believe you that your all-spanish cedar sounds beautiful. A few days ago I was on http://www.12fret.com/, a website that I like very much, as they often have soundfiles for the high-end guitars they sell. I just wanted to get a feel for different top woods that I have never played myself by listening to a couple of guitars.
I came across a guitar by Sergei De Jonge http://www.12fret.com/new/de_Jonge_Spanish_cedar_guitar_pg.html made of spanish cedar. That's one of the sweetest sounding guitars I ever heard.

Much of this may have to do with Sergei De Jonge being the builder, but I decided to give an all-spanish cedar guitar a go

Christian