http://nsweb.itinfo.dk/UK/3DL_Technology.aspVid on this page shows the process. Shows the differences between the more traditional broad-seaming style, to the very tech 3DL style.
Seen many of these sails as I am usually in adventureland (ie bowman) when yachtracing. Massively lighter than a panelled sail which is great. But once the sail is made, limited re-cutting available. Generally only the luff curve can be changed.
