Sails and Furling

Sails. Bit-by-Bit is a sloop-rigged cat, meaning she has one mainsail and one genoa sail. A cutter has two foresails in addition to the main: a genoa and a jib. The jib is smaller than the genoa, and they both fly from the forestay aft. A jib by definition is smaller than the triangle formed by the mast and the forestay, while a genoa extends past the mast and is known by the percentage it overlaps. Bit-by-Bit used a 130% genoa, meaning about a third of its foresail overlapped the mast.

Both rigs can fly a spinnaker when sailing downwind.

The old wooden warships had four masts: bowsprit, foremast, mainmast and, at the aft end of the ship, the mizzenmast. The three vertical masts each carried at least three layers of sail rigged across the ship: on the bottom, in the middle against the mast, were the courses: the forecourse, maincourse and mizzencourse. Above these were the foretopsail, maintopsail and mizzentopsail, then came the Topgallants, and sometimes, the Royals at the very top. On the outside edge of the courses, topsails and topgallants, were the studdingsails, named in the same way to identify the mast and layer. There were a few fore-and-aft-rigged sails between these masts (called staysails), and more of these fore-and-aft-rigged sails flew from the bowsprit: jibs, flying jibs, and the foremast topstaysail.

The first photo is Bit-by-Bit’s spinnaker viewed from the trampoline. About 1,400 square feet of sail. Next is a fixed wing trimaran built by Walker Marine (sadly now out of business, I think) called The Zephyr. A rigid wing is a more suitable form of aerofoil than a flimsy sail and it can be feathered in case of high winds. Next is Bit-by-Bit flying her mainsail and genoa, with the sails set to each side (wing and wing) to maximize thrust sailing downwind , and in the last photo taken shortly thereafter, using the correct sail for downwind, the spinnaker.

The Spinny 2 Knysna - Walker Zephyr 2 BB II on Lake Ontario BB II on Lake Ontario (Spinny)

Furling a sail is similar to reefing the sail in that it reduces sail area. Furling a foresail is accomplished by wrapping the sail around the forestay using a device called a Furler. In Bit-by-Bit’s case the unit was made by a company called Profurl, and consists of bearings which allow the forestay to turn in place, a special casting into which the sail’s boltrope is inserted (more on this below the photograph) and control lines. In the photo, the Profurl’s yellow drum can be seen on top of the beam.


The forestay for a furler carries a piece of metal which runs the length of the forestay, with a slit cut into it. An wider hole in cut into the base, into which a sail sewn around a rope is inserted and pushed all the way up the slit to the top of the forestay. The boltrope keeps the sail tightly in the slot and when the forestay is turned, the sail wraps around it. The furler is turned by pulling on a line wound round a drum at the foot of the sail. The sail can be wrapped completely around the stay, or as little as needed for reefing purposes.

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