I've been following this thread with interest. I'm not ready to make a DB, but am working on an archtop guitar at the moment. I've carved the top, and am just getting ready to start carving the back. I used the Lancelot on the top and will definately using it on the back as well. As has been suggested by others, I will be drilling reference holes to assist for getting the depth close. Then I will be using finger and palm planes, followed by scrapers for final smoothing. There is a great description in Bob Benedetto's book on arctop guitar making on carving a top this way. I couldn't imagine carving something as big as a bass without the assistance of the Lancelot. Just make sure that you clamp your top or back to your wook table. You wouldn't want that beautiful piece of wood flying off your bench. (No, I'm not talking from personal experiance.) Just my .02 cents. Good luck with however you decide to carve it out.