Official Luthiers Forum!

Hello everyone, I am planning on purchasing a redwood top for my first solo build this week and I was just curious as to typical thickness of redwood tops. Thanks for the input, I am incredibly excited to get this build started and begin learning more.

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--Kyle Burner--

Hi Kyle - before everyone gets into to how they determine top thickness with deflection testing and assuming that you don't deflection test yet a good ballpark thickness for a typical redwood top would be a bit thicker than spruce and a bit thinner than cedar or .120 - .125ish.

First off there is so many things driving this but in general for a steel sting with around 160+lbs of string tension I would start at .118-.120 prior to tuning and thin the perimeters as needed. For 140-150 I would start at .115-116.

When working with Redwood work clean and careful. They will ding deeply if you breath to close to them.

Thanks guys, since I am new to this I am still figuring out how I will do deflection testing and all that. I really just needed a ballpark number to start from, so your answers were perfect. I am sure by searching the archives I can find a boat load of opinions on how deflection testing should be done.

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--Kyle Burner--

The stiffness of soft woods along the grain is pretty much proportional to the density, no matter what species you look at. Most of the redwood i've tested has been denser and stiffer than the average piece of WRC. The surfacehardness is usually higher for Redwood than WRC too, so it's a bit less prone to denting.

The big advantage of redwood is it's low damping factor; it rings forever when you tap it. This helps give the gutiar a nice 'warm' but 'clear' sound if you do it right.

Redwood can be difficult to glue. Be sure to allow the center seam to set up overnight, at least, before you take it out of the clamps.

Redwood also tends to split easily. Keep your shophumidity low to avoid top cracking problems down the road. I also like to use a bridge with a wider footprint than usual, which minimises the chance that it will peel up and take some top wood with it. I like to use walnut in these cases, to help keep the bridge weight down.

I built a 00 size guitar of redwood/cherry to take to the Montreal show, and it got a lot of play. The top is 3.2mm (.125") thick at the upper edge, and tapers to 2.5mm (.098") at the lower block. So far it has not been distorting noticably.