I would recommend Todd Bradshaw at Addiction Sailmakers, 210 Merrill Crest Dr. Madison WI 53705, (608) 233-3223. He literally 'wrote the book' on the subject. His book is available from http://merchandise.wcha.org/product_info.php?cPath=92&products_id=436 if you want more information. He is also an active and helpful member of these forums so you can easily search for his previous comments here.