Tagging onto Rick Dinon's question about recuts here is a more specific question. My 150 tri-radial (about 10 years old) needs a recut or replacement. It's made of Norlam (people have said that once Norlam starts to go it's 'gone'), I=42, J=12'2", fabric weight was for apparent wind up to around 18 or 21 knots but don't remember the actual weight. The sailmaker (not the original) wants recut it buy taking some material out of the luff. To slightly complicate things, the leach has a transparent plastic UV panel. Originally, it was my understanding that with a tri-radial one could recut it (when the time came) more exact by working the panels. My preference is for a shape that has most of the airfoil curve in, say, the first 1/4 or 1/3 near the luff and then is flatter aft. I don't see how taking material out of jsut the luff will correct the basic shape problem of what looks like a more-or-less long continuous curve with the center of the draft close to the middle of the sail. But then I'm not a sailmaker either. Obviously doing more than one seam rip and sew will cost more so there is an economic solution to consider. Can you recommend any book(s) for an amateur to read which would help with this? I already have "Sailpower".