Measuring the Tack Cutback of the Sail

"In this clip we're going to talk about how to, how to figure out your tack cutback on the sail. Another topic that's very important in your sail design is the tack cutback and the tack cutup. So this determines the exact tack location of the sail. And the reason this is important is to get a very smooth, smooth sail shaping out of the tack and avoid wrinkles, and just make a better sail. So we're going to show some measurements here and exactly how to measure and design your tack cutback. So what you want to do is from the aft face of the mast here, you want to measure to the bearing surface on the pin on the tack pin. In this case, you can see it's one and three quarter inches. And when we get to actually making the sail, you'll see us draw the luft curve and after we draw the luft curve we'll cut the tack cutback. So we have one and three quarter inch tack cutback on this. The tack cutup off of the boom is about three eighths of an inch. The sail edge will extend past either end of the grommet, but we need to get the bearing surface of the grommet in the right position. So when the grommet is in the proper tack position and pinned, the sail you can see, needs to exit the mast and have, like I said, the tack cutback. So you can see we're using a number two spur grommet here which is an appropriate size grommet for this sail. and when we actually cut the sail, as you can see, we'll probably actually only cut the sail back about one and an eighth inches. And when we actually cut the sail for the tack cutup, we'll probably only cut it up about a quarter inch off the foot rope. Okay, that's all for the tack cutback."