I would like to make two points that Ed and I were discussing.



In Rick's book, Catamaran Racing For The 90's, in his chapter on battens, where he talks about using the fish scale, he describes a method for identifying, older, stiffer, and potentially heavier battens. Fiberglass battens stiffen as they age.



Second. Using a fish scale to determine your draft location is new to me. I would make two minor points on using this method. If you taper your batten at 40% using this method it will not be at 40% in the sail because you have not calculated in the leading edge of your sail (the mast). Also as Rick mentions in the batten chapter when sheeted in the draft may be blown 5-10% further aft. Using this method will get your sail in the "ballpark" but I think a more precise method is the one David Tilley mentioned. It is described in greater detail in Phil Berman's series of performance manuals for the Hobies.



It is probaly worth repeating that you want a gradual shift of pocket position as you move up the sail.



Happy sailing,

WindOverWater