Page 64 - The Complete Rigger’s Apprentice
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Figure 2-25. A self-tailing winch ingeniously eliminates the need for a human tailer. Since they’re not fail-
             safe, don’t trust yourself to a self-tailer when going aloft. Note that if the winch is worked with the standing
             part at the angle shown, an override will result; the standing part should lead slightly downward (dotted
             line). (Margaret Wilson-Briggs)

                                                         are two more candidates for block-and-winch team-
                                                         work. An extra part or two on a purchase means you
                                                         can go with a smaller winch that will receive less
                                                         strain than a larger one doing the job all by itself.
                                                             A modern sail plan comprises a few large, very
                                                         powerful sails. The intent is to produce greater
                                                         efficiency and less complexity than the traditional
                                                         approach of more and smaller sails. But the mod-
                                                         ern sail plan concentrates forces to such an extent
                                                         that a large, expensive machine—the winch—is the
                                                         only practicable way to make things work. Largely
                                                         because of market pressures, boat manufacturers
                                                         tend to fit winches that are smaller (and thus cheaper)
                                                         than you and I might consider ideal. Smaller winches
                                                         are less powerful, so the price we pay for lower cost is
                                                         increased physical effort. What is more, every winch
                                                         suffers some loss of efficiency due to internal friction,
                                                         even when it is exquisitely maintained.
                                                             How big, then, does a winch have to be to
                                                         overcome both the pull of the sails and its own
                                                         drag? The answer starts with how much effort is
                                                         acceptable for you. For most people, 35 pounds
                                                         (15.9 kg) is a comfortable maximum sustained load.
             Figure 2-26. Human tailer.
                                                         An undersized and/or badly-maintained winch


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