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I actually know what this is. Curious if others can ID

My first guess is sinker redwood…

+1

Very impressed. Very! It is indeed coastal redwood. Cut about 120 years ago. Used in Earnest and Julio wine casks. Estimated to be over 600 years old. Staining is due to the wine. Got access to a bunch of this. It is so amazing.

I think the primary use is tops, but I’m gonna try two bodies.

I can’t tell for sure in the pic but the endgrain makes it look so off quarter as to be entirely inappropriate for top material.

Redwood has material properties that are so all over the place that I’ve frankly given up on it. It hasn’t brought anything to the table that I haven’t found better elsewhere, except perhaps a bit of market cache.

You might be right. But I’m gonna try. What’s to lose?

Well Mike, you have experience with this so I am not going to say I know better. The one guitar that I have built with flat sawn timber has shown a lot more instability with humidity, compared with quartered panels. One option would be to laminate it with something else on the inside so that you get the beautiful look of that redwood but you are not gambling on its stability and stiffness. Laminated back and sides can make great guitars. What are you going to use for the soundboard?

Very cool! Brace it in 30% RH or drier and it should be fine. Redwood is brittle so it will crack from relatively little contraction, but has very low humidity expansion so you don't have to worry much about swelling in high humidity. This one is roughly 45 degrees and hasn't had any trouble, despite some extremely dry winter days http://www.luthiersforum.com/forum/viewtopic.php?p=647385#p647385

Yes, I was indeed thinking of laminating it. And if it doesn't work out, gonna make a table with it. What would any of you use as the laminate? Wood type? Cut type? (quarter/plain). And how thick? (or what percentage of each, laminate and exterior wood?)

As stated above, two concerns are flat sawn stability and brittleness.

I laminated a redwood top with spruce, which seemed to make perfect sense to me.

From the Wood Database for Coast Redwood:
"Redwood lumber is very soft and lightweight, with a decent strength-to-weight ratio. It is also exceptionally stable, with very little shrinkage or seasonal movement."

Being pretty well seasoned by now, and appearing rift sawn rather than flat sawn, I would do as Dennis suggested - brace it at lower than usual humidity levels and hope for the best. I think laminating with a dis-similar material might actually add some stress.
If you find that it doesn't work out for soundboards, it might make a nice solid body guitar if the dimensions work out.

Are people thinking it's not quarter sawn because of the dark discoloration line that runs at a diagonal on the lower right endgrain of the piece?

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

I carved an archtop with curly redwood. I thought it seemed flimsy. It was less scary after a coat of Zpoxy! I thought the wings on the f holes would break off. It worked good. I like the way it sounds. I started with nylons on it, but it wanted more, so I put 80/20's on it after a very short time. The belly has risen some, but not lately. The adjustable bridge ran out of adjustment, but I lost a lot right from the beginning, just because they are made for very flat archtops. Mine has a full arch. Solid bridge now. I work pretty light.

You could always keep it thicker.

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Why be normal?

This particular piece is most def plain sawn. And I’ll bet most of it is as well. My first thought was for a table I’m building. That’s gonna happen. I think for guitar tops, properly laminated it will work.

Study the diagrams for quarter, rift, and plain. I might find a piece plain sawn out of center. Or near center. And that would do the trick. Supplier has a lot of it.

Barry,

Did u orient the laminate spruce 90deg to redwood grain?

Nope. Parallel.

Ok. What thicknesses would say you started with and then ended with? I mean thicknesses of both materials, not composite thickness

Its been a few years so don't have exact numbers but I think each layer was about 50 thousandths thick. The resulting lamination turned out to be pretty stiff.