Hi,
I have no experience with wood, but maybe you could make some use of my method.
I make wooden propellers of plastic sandwich of white and black sheets glued together with Tamiya Extra Thin.
After sanding the final shape of the prop I use oil paints to create the wood grain.
Not sure if this will be suitable for such a big scale, however. The propeller on the pics is in 1:144.
Cheers
Ondra