![]() ![]() In some cases, what was an adequately smooth lead for stainless wire will need a bushing to protect the less abrasion-tolerant fiber rope. The bottom line is that there is a big difference between a sharp-edged hole drilled through a stainless-steel stanchion and a smoothly rounded lead at the top of the same stanchion. Abrasion will become more of a concern, and each hard spot or contact point along the run of the line needs some consideration. Obviously, strength and reliability are key concerns when installing a rope alternative to wire. ![]() Those who are already familiar with using cordage strops and lashings to attach hardware will feel more comfortable with a fiber lifeline installation. (The HMPE 5.1 is a prototype lifeline developed by New England Ropes it is not yet on the retail market.) For the first round of the comparison, we installed an HMPE 5.1-millimeter, special double-braid lifeline for the top lifeline and an Endura 12-strand single braid for the bottom. Steve Parola at New England Ropes has provided us with several high-modulus line options. In this first phase of the test, we look at the issues involved in transforming one of our test platforms, Technical Editor Ralph Naranjos Ericson 41 sloop, from wire to Dyneema SK-75 lifelines. Naval Academy to determine the value of high-modulus rope alternatives versus stainless-steel wire lifelines. Practical Sailor has launched a long-term, in-depth set of seatrials linked with lab testing at the U.S. One of the key attractions of these lightweight fibers is that they allow ropes to be made as strong as stainless-steel wire of equal diameter, yet they weigh a fraction of the wire that they replace. Dyneema and Spectra are brand names for lines made from trademarked HMPE. Sailboat lifelines have jumped back into the spotlight thanks to a growing acceptance of-and some controversy over-high-modulus rope like Dyneema and Spectra being used as an alternative to stainless steel. We learn to reach inboard for handholds, make sure that the nonskid on the deck and cabinhouse affords good grip, and avoid leaning outboard using the lifelines like a banister on a staircase. The recreational sailor needs to become more deck agile than the average passenger on a Block Island ferry. We are not advocating 40-inch lifelines on 30-foot sailboats, just pointing out that the minimum standards for recreational sailboats don’t go very far toward preventing crew from ending up in the water. Its a legitimate design compromise, but theres little doubt that you are more likely to go over a side thats bounded by a 2-foot-high wire railing than when youre held in check by a restraint more than 3 feet high. Despite the fact that human size doesn’t vary between commercial and recreational craft, the lifeline minimums are scaled back for recreational sailboats. Code of Federal Regulations 28.410 mandates that commercial vessels have lifelines, deck rails, or bulwarks that are a minimum of one meter (39.5 inches) high, with stanchion spacing no more than seven feet and no greater than 15 inches between wires or tubing. When using high-modulus fiber lifelines, the type of splice used should be what the manufacturer recommends versions of the Brummel splice are often the preferred approach for placing an eye in single-braid line. Socket mounts with set screws or self-tappers have been known to work free. If socket-type bases are used, through-bolting, welding, or bonding is mandatory. For boats over 28 feet, they must be a minimum of 24 inches above the working deck and be made of uncoated wire or the equivalent high molecular weight polyethylene rope (HMPE) like Dyneema or Spectra. The International Sailing Association and Federation (ISAF) Offshore Special Regulations give considerable attention to lifeline design. ![]() Clevis pins, cotter keys, turnbuckles, swages, spot-welded pulpit connections, and gate hardware add up to a lot of potential points of failure. These bits and pieces act like links in a chain or a fuse in a series circuit-any one of the lesser components lets go, and the entire system fails. Theres often an array of minor hardware playing a major role. The system comprises more than stainless-steel tubing and wire or high-modulus rope. ![]()
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