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As they say,
so making a copy of my Gibson AJ, a terrific guitar in mine opine. While making a plan with measurements the top came out at .140 which just seems absurdly thick, yet this guitar is very nice. Unlimited headroom, loudest guitar in the jam whilst gently plucked for single note shenanigans, ful in so many ways. But .140? Does anyone else have one to share diagnostics?

Your avatar is creating a great deal of envy! I think I will forge ahead at .110 and see how it goes...

I've had very good results with tops .120 to .140. I guess I'm not sure what all the fuss is about thin tops. One of my best sounding guitars finished around .145.

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"No man ever steps in the same river twice, for it's not the same river and he's not the same man.” -Heraclitus of Ephesus

A couple of months ago I bought a partially assembled ADJ that had been used as a display model at a Gibson dealer. The back and sides are glued up and the top is fully braced and ready to glue up. I mainly bought it so I could make good accurate measured drawings of the thicknesses and bracing layouts since I love all the slope shoulder Gibson styles.
I measured it last night found that the thickness of the top is .120 at the soundhole and a pretty consistent thickness of .125 around the edges with no more than about .002" variation. I could take a few pics of the bracing layout if it helps.
Interestingly, when I lay the body down over the OLF ADJ plans that I got a few years back it doesn't really jive up. It matches more closely with the J-45 plans from Stew Mac, at least as far as the body shape.

.140 is not that thick. Nearly all of the 100+ guitars I have built have had tops in the .130 - .140 range. I do thin them 20% or so toward the edge, though.

Mark

Thanks for the info. I don't suppose you'd mail me that top? Kidding! I took some time to map out mine as close as I could, it should be fairly accurate. Some anomalies I noticed were that the bass x is much wider grained than the treble.
Here's what I found
x's 9/32x 21/32 (.650)
bass scalloped to leave 5/16 in height
treble to 3/8
tone bars 9/32 x.650 scalloped to 11/32 height
thumbeam was 9/32 as well with radius transition starting a lot closer to the fb than I would have thought structually sound. I make mine far more robust.

Like Mark B, I'm in the thick top camp. Nearly every one of my sitka topped guitars start out .125+, then I do a thinning around the perimeter of the lower bout. They articulate, project and sustain as well or better than the lightweights I run across.

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michael propsom
www.propsomguitars.com