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That top should be fine if it's a 'normal' top with a specific gravity of about .43, which would be pretty average for Sitka or Red spruce, and assuming the thickness averages about .105". If the sp.g. is on the low side, around .38, it would need to be thicker, closer to .118". At .105" it would be about 40% less stiff than I'd make one. Sitka or Red at that density is not common, but I've seen it. If the sp.g. is on the high side, at .48, the top would only need to be .094" thick, and your top would be 30% or so stiffer than it needs to be. It's not unusual to find Sitka or Red in that density range. You can't tell what the density or stiffness are by looking at the top, you have to measure them!

Cool, so how do I measure that? U have another sitka top I'm about to glue up. This time I'll only sand it enough to get my rosette installed before bringing it down .

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Hutch

Get the heck off the couch and go build a guitar!!!!

Finding specific gravity is easier done using the metric system. Multiply the length, width, and thickness in centimeters to find cubic centimeters and then divide by the weight in grams (this assumes the top is still rectangular). You will have to average the thickness of the top to do the calculation, or you could do the calculation using the minimum thickness, and another using the maximum thickness to find the possible range of Sp.G.

Great! I'll give it a try. I don't own a scale though I'll have to bring it to work. I have been considering getting a scale and weighing everything.

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Hutch

Get the heck off the couch and go build a guitar!!!!

It'll be fine. Just call it your "Responcive Finger Style Banjo Killer" model.

A scale is a good thing to have in the shop.