Appendices -- Useful Supplemental Information

(From an article in WoodenBoat #123, March/April, 1995. By S. K. Hopkins, with illustrations by Dee Carstarphen.)

THE BYPASS REEF

Traditional mainsail reefing, refined as “jiffy” or “slab” reefing, has been proven by hundreds of years’ use aboard commercial and pleasure vessels.

Unfortunately, in its most usual form, it can do costly damage to the sail. Sailmakers often see the result: chafed, lacerated, or torn cloth that was trapped under the two parts of the leech reef pendant and exposed to the in-running nip where the pendant enters its cheek block. When powerful reefing gear is used, or when the reef is carried for long periods in heavy weather, this abuse can require major repairs.

It need not happen. Without changing or adding hardware this potentially dangerous condition can be altered to a safe one.

The trick is a simple re-routing of the reefing line. I call it the bypass reef. To adopt it there must be space between the foot of the sail and the boom. The effects of the bypass are so salubrious, it might be worth while to convert a boltrope-in-boom-slot sail to one with slugs. (Which will also allow a vang strap to be passed, ease the job of bending on the sail, and allow sail stops to pass through, promoting a better furl and keeping the sail atop the boom.)

When a sail with a bypassed pendant is reefed, all the bunt is left outside the finished configuration, and the full length of the bunt can be made into a continuous seamanlike roll. Most important, the sail will set better, because the cringle will be on the boom, instead of stopped by inches of wadded cloth, and will probably have been outhauled more successfully. The boom will be tangibly higher. If a second reef is taken, and its pendant has also been bypassed, it will come cleanly down to the boom independently of the bunt already reefed.

Note: Defying first guesses, the bypass reef functions smoothly on both tacks -- the bunt of the sail invariably falls outside the completed reef whether to leeward or windward.



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