The fluting is a natual effect of the wood having no support through it's curvature for the outer (wider) posrtion of the rib. The inner portion of the rib is continous for the entire length of the rib. As the rib tapers inward at the ends, the support is lost for the outer curvature and it tries to bend back to it's original shape. The thinner the wood, the more pronounced the fluting. At 1.7 mm thick in maple, there is not much fluting. At 1.2 mm thick, the fluting becomes pronounced.
Louis Aull -- To get on or off this list see list information at http://www.cs.dartmouth.edu/~wbc/lute-admin/index.html
