By Peter Nielsen
Many drivers develop a kind of mechanical sympathy—they learn to recognize the sounds an engine makes when it’s being over-revved or is in too high a gear for the speed. The ability to empathize with sails is not so easily acquired, which is one reason why sailmakers will never be short of repair business.
Step one is to keep the sails from flogging. Flogging is bad news, because it breaks down the filler that is put into the sailcloth to stabilize the weave and keep it from stretching. Once this filler is gone, so is the sail's ability to retain its shape. This will happen inevitably over time, but there is no reason to speed up the process.
On short-batten mainsails, the cloth immediately in front of the batten pockets is usually the first to suffer the effects of flogging, which results in a noticeable “hinge” effect. Eventually the Dacron fibers will break down. Full-batten mainsails are much better in this regard. When you’re reefing the main, rather than dumping the sheet altogether and letting the sail flog madly, try to spill just enough wind to take the weight out of it so that you can drag the luff down easily.
Leech flutter in the sails might be mildly annoying to the crew, but when it’s prolonged it can gradually destroy the sailcloth. The noisy, rapid-fire flutter known as “motorboating,” which often occurs when the headsail is strapped in hard for a beat, is especially damaging. Don’t be afraid to tension up the leech line to get rid of this horrid noise—and don’t forget to ease it when you come off the wind.
There is a lamentable tendency to treat sheet leads as if the cars were bolted in place. It’s all too common to see boats blithely sailing along with the bottom half of the genoa trimmed correctly while the upper part of the leech is flogging away, out of the crew’s sight. This can be avoided by using the sheet leads correctly—moving them forward when the sail is reefed, and also when the boat is put onto a reach. If they’re too far forward when you’re beating, there will be too much tension on the leech; if too far aft, the foot will be overtensioned.
When you’re tacking, release the lee sheet early enough to prevent the sail from catching against the spreader as the boat comes about, then sheet in quickly to minimize flogging. And don’t trim the genoa so hard that it rests against the spreader; 4 inches off, or so, is enough for upwind performance.
Lastly, don’t overtension halyards. They should be just tight enough to get the horizontal wrinkles out of the sail. If vertical creases appear, the luff tension is too high, and continued abuse can deform the sail. When you leave the boat, ease the genoa halyard and the mainsail outhaul; leaving tension on them can result in permanent stretch in the boltropes.