Oops

[Dave Bagwill]

All I've done is join the top and back. I hope to get a lot done this next week.

[Jackspt28]

Hello Dave , I did the same thing on a nice striped sinker red cedar top , I am at .100. After reading replies to my thread , I ordered the 4 small body guitar templates from Ken and will use this top on a Martin size 2 guitar. I can only hope it will have the sound qualities of the one in the video posted by Preston Thompson. I will be bending sides for that one in a couple weeks. Jack.

[peter havriluk]

I'd like to ask a question, please:

Moving right along, are there 'ballpark' thicknesses for various soundboard materials when the builder (me) is clueless about tap testing, for example, sounds like on a dreadnaught sized top of cedar (wrc?), .110 seems to be a stopping point and for mystery spruce (prs?), .090 gets the stop sign. Generally speaking, any idea of thicknesses for smaller guitars, too, GS Mini sized or so? And a translation of the initials?

Thanks!

[John Link]

Hi Peter.

Both Brian Burns and Ervin Somogyi adjust thickness to stiffness, as a starting point. Burns aims at a resonant frequency of 75 hertz for the bare top, Somogyi to a certain amount of deflection. Somogyi, however, has publicly stated that this translates to the neighborhood of .095 inches as a general rule (I assume this is for spruce, not cedar or redwood), noting that the actual thickness for each top is a function of the specific piece of wood used. (Somogyi builds light.) Somogyi also offers an "in progress" PDF to the public that discusses top thickness in great detail, including how it has been treated in the standard books on guitar making:

http://www.esomogyi.com/top_thickness.pdf

[peter havriluk]

John, thanks for the link. So that's the problem I was asking about. Mercy. Still, it sounds like I at least ought to keep good notes when I build something. I infer that there's a baseline to working towards a goal, and that baseline is (documented) project number one, followed by playing the instrument, followed by project number two containing deviations from project number one, hopefully in a good direction. I think.