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For the builders who have built guitars with these woods for tops, how differently (if at all) do you treat either of these two species from building with spruce?

For example final top thickness, bracing, deflection testing, pore filling, etc...

I am on the other side of the fence I have built Koa tops but no Hono mohog. I started my Koa tops at .15" and thinned out after bracing on the first couple They ranged from .095-.100 at the edges after tuning. The later versions I did I thickness to .100 to start with and thinned to .092-.095 at the edges


Koa has some pretty deep pores I pumice filled the first couple and Zpoxy filled the rest. If you Zpoxy fill be sure to work the epoxy int to the pores well and sand back to bare wood surface with the Zpoxy still in the pores. Seal with shellac after you sand back to bare wood or a 60% alcohol-40% Zpoxy mix leaving no real film thickness. You do not want to leave a Zpoxy film of any noticeable thickness on the top as it will dampen the top. But you do need a good fill or you finish will sink

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Thanks for the replies Todd, Michael and Tony...

One of the things I love about this place is that folks are willing to freely share their experiences; and that you guys all have three pretty different experiences/opinions.

I have some pretty different sets of Honduras mahogany: light in weight and color; nicely figured lighter in color; and some darker, heavier stuff that has a tap unlike mahogany in that it rings a bit.

I would first think that the lighter weight stuff may make a better top, but if I thinned it as much as Todd suggests I bet it would get pretty floppy. I will be bracing these tops with some nice stiff Red Spruce bracing stock.

I have seen some older 0-17s that had very thin tops and seemed to be standing the test of time pretty well. Just last week a friend found a great late twenties L0 similar to the plans put out by the GAL. This little Gibson was so light, with my eyes closed I probably couldn't have been able to tell it was a 'hog top. These little L0s are very different in that they have an 'H' pattern bracing.

Michael, I think your idea of sanding the Z'poxy back to the wood may be best for the top. Thanks for the tip(s) guys.