Paul, I have made a few. I use brass as the 'spine' and then add the wood as a skin. Look at
this thread and
this one for some pics of my process.
Of course the purists will tell you I'm doing it 'wrong' because they all use ebonite or acrylic as their spine ... You tell me how much diffs there *really* is ...
Ed, I do use a metal lathe to machine the brass, but bear in mind that a metal lathe in its basic form differs from a wood lathe only in that there is a carriage driven by a worm drive in place of the banjo. In every other respect they are mechanically identical. Again, how different is the process *really*? If you are referring to a CNC lathe then I get your drift, but I don't have the luxury of one of those!