Too thin?

[KreherGuitars]

I am preparing for my second build as number one is getting finish. And I have some concern with with the target thickness I am getting. It works with all the book examples. The spruce is German spruce. It feels especially stiff but not exceptionally. I have not worked with German spruce before. My numbers are this:
Length 590 mm
Width 227 mm
Thickness 4.1mm
Mass 235.5 grams
Density (calculated by program) 428.87
F long 63.25 hz
F Cross 113.72 hz
F diagonal 175.63
Steel string target stiffness 75
Guitar body length 524mm
Lower bout Width 380mm
Shoulder width 265 mm

And I am getting a target thickness of 1.8mm. Do any of these numbers look wonky to you? One thing I want to check tomorrow is making sure all my settings are correct for taking the frequencies.

[Bruce McC]

Hi

I think your F diagonal of 175.63 is suspect, too high.

[kiwigeo]

1.8mm sounds too thin.......might be ok if you were making a lute

Check your tap frequencies

[johnparchem]

your fdiag is way too high. It is a hard one to get as it will be 30 or 40 Hz. So I just set that part of the equation to a nominal value of 1 and I get around 3.1 mm. Your other frequencies are close to what I would have expected. This looks like a reasonable thickness to me as it is a big guitar.

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