Very interesting! The one thing I haven't figured out how to do yet is to create the proper stepped forms to create the basic shape of the prop. I just end up laminating a large slab and then cutting away the extra. But this is not only wasteful of wood but, in terms of wooden propeller technology produces a weaker prop because the grain isn't ideally aligned (lengthwise) in each layer.

WWI era props used between 5 and 8 layers. In most cases slightly different woods were alternated for better strength but only rarely did that result in the strongely striated props we modelers love so. In fact, this seems to have been primarily a feature of German prop manufacturers.

BTW, Von-J's link provides a nice link to an RC-Groups thread on carving scale propellers:

http://www.rcgroups.com/forums/showthread.php?t=541181