I learned to perform some common repairs on a sail this month. The photos show an example of a patch. My patch covered an old patch, that had likely been stained by mildew. My patch also covered a part of the green cover that showed wear and tear, which occured as a result of chafing on the boat’s spreaders when the sail was in use. Spreader chafe is common and this example of a patch is known as a spreader patch. The patch sandwiches the sail, beginning on the starboard side, wrapping around the leech edge and over onto the port side. The goal is to make both sides of the patch the same size and perfectly aligned so stitches capture both as the sail feeds through the sewing machine.
I built the patch out of two kinds of fabric. One is an chafe resistant fabric called Odyssey. I chose green Odyssey to match the sail’s old cover. The old cover is made from Sunbrella. Sunbrella protects the sail against the sun’s ultraviolet rays, but is not designed to withstand much chafe. The white fabric is Dacron, which matches the rest of the sail.
Patches such as these are always trapezoidal, with a longer outside edge and a shorter inner edge. The idea is the wider part of the patch will cover the area that needs repair and the rest of the patch tapers into the intact portion of the sail for a finished look. The patches should also blend as well as possible with existing materials. Each raw edge of the differing patch fabrics is tucked and fitted together just so to make the seam as, well, seamless as possible.
Everything I know about sailmaking I’ve learned at the loft. So, repairs can trip me up because many of those sails come from other lofts or factories that use different technique (or less technique, it seems). In the instance of this repair, the sail was factory made, its cover was made by my loft years ago, and the old mildewy patch, who knows? As a result, we sailmakers perform a kind of phorensics to determine what caused damage and how to repair it, sometimes flexing our tried and true methods to work best with the sail we’re presented with.
Being new to all that, I made a mistake with my patch construction because I assumed the old, mildewy patch was aligned perfectly, like ours are. That wasn't the case, however. So, the patch I constructed covered the old patch completely on one side of the sail, but left a small portion exposed on the other side. At a quick glance, the average person might not notice. My loft prides itself on precision, however, and I got the usual smile from my co-workers and a friendly, "just don't do it again."