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So I luckily have a few large Honduran mahogany rift sawn boards. Contemplating making an all mahogany 000. I realize there are plenty of things to consider but in general, would you make the top somewhat thinner than say a sitka top? Say ten to twenty thou thinner?

I made my first Mahogany topped OM a few years ago. I used the same deflection numbers I used for spruce and it turned out quite well. I’ll have to look up what the thickness came out to be.

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I’ve done one. Based on advice from here, I thicknessed it to equal the deflection (by feel) that I normally use for spruce tops. It came out at .117” a bit thicker than I usually use for spruce. It sounded wonderful.

Thanks guys. I had some of the same thoughts around stiffness and likely weight too.

Generally if you are sanding to deflection mahogany will wind up thicker than spruce.

The last few that I’ve done I’ve made them 20% more flexible and made up the stiffness with the bracing and they’ve been pretty successful guitars…

The mahogany I've tested has had Young's modulus numbers along the grain that are pretty close to the denser spruces. A strong 'stripe' figure is a sign of lot of run out, and that reduces long-grain Young's modulus values. Since that's the primary thing that determines how thick the top needs to be, you end up making them about the same thickness or a bit more depending on the figure. However, mahogany is usually denser, so the top weighs more. This is going to favor bass over treble, and 'headroom' over 'responsiveness', and less power overall. Naturally, each piece is different.

I've often thought that a cedro ('Spanish cedar') top would be a natural choice with mahogany B&S. The look can be similar, but cedro tends to be lower in density, with decent long grain stiffness. It may be hard to find in sufficient width, though. I remember seeing three cedro planks at a yard about 25 years ago that were 2" thick, 10 feet long and 40 inches wide, but they were flat cut. Impressive.

Yeah, I would like to try a cedro top. Another I've always wanted to pair with mahogany B&S is primavera. Similar look but lighter colored. Lower Young's modulus than cedro so it would be heavier, but still lighter than a mahogany top of equal stiffness.

Primavera makes a fine non spruce sounding top…

I have a few planks of Cedro that I usually make linings with. I can taste it as we speak. Good call on trying it for soundboards. My try it and build it list will definitely outlast me I'm afraid but it is on the list!

I can taste it too and I haven’t had a taste for years, lol…

Cedro has to be one of the best smelling and worst tasting woods out there.