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The Bruce Anchor Sets Best In our tests in sand of 11 anchors, the Digger and two prototypes fail to set at all three scopes used. For the others, setting is sometimes a trade-off with holding power. A goodly portion of the best years of every sailor’s life has been spent reading reports on, opinions regarding, claims for, studies of and test results about those odd-shaped objects called anchors. It’s all in search of an all-purpose, never-failing, indestructible contraption with which one can attach the confounded boat to the crust of the good old earth, which unfortunately can be sandy, muddy, stony, rocky or weedy. There are but two questions: Will the anchor set? Will the anchor hold? Tests? There have been dozens of them—the French APAVE, the U.S. Navy tests, the RNLI (Royal National Lifeboat Institution) in England, the BOAT/U.S. and Cruising World magazine strength tests, the so-called Dutch tests (which were done in a huge sandbox), the on-going tests done by the naval architect and author Robert A. Smith, and lots of tests sponsored by anchor manufacturers. Even the most recent impartial tests often aren’t very definitive. Perhaps the most noteworthy of these was the “Seattle Tests,” co-sponsored by the Safety at Sea Committee of the Sailing Foundation and West Marine. It involved two trawlers, two tugs, dozens of workers (including divers), five different sites in Puget Sound and 253 “sets” with seven anchors. Our exclusive report on the Seattle tests appeared in the February 1, 1996 issue. Better Mousetraps Is there such a thing? Probably not. So, let’s take a different cut at it. Which anchors excel or rate among the best in the various functions assigned to the anchor? There never appears to be any disagreement that an anchor’s major functions are: 1. Setting Four less important factors in anchor selection might be considered (1) the difficulty of breaking out, (2) weight onboard, (3) the quality of workmanship (as it pertains to long-term utility), and (4) ease of handling and stowage (either at the bow or in an anchor locker). With many boat owners, stowage, self-launching and automatic retrieval from the bow is a great plus. Conversely, no one likes to be forced routinely to break an anchor out of deep stowage, especially on any fairly large boat that requires an anchor of unhandy size and weight. Indeed, for those who anchor often, self-launching and stowing can rank very tight up behind the three major functions. How To Begin Someone who sails in nice weather on weekends in protected water, never far from a nice harbor in which to have lunch or take a nap, can rightfully be said to have anchor needs radically different from the ocean cruiser wandering the world. Most of us fit somewhere in-between and can be described as sailors who occasionally get caught during very bad weather in an anchorage not of our choosing. The latter instance makes anchor selection very difficult. Whatever the need, we’re reasonably sure that setting is one of the two most important major functions of an anchor. Setting and holding are inextricably linked. But an anchor is useless if it doesn’t set and leads to nervous disorders if it sets “62% of the time in sand, 29% of the time in shingle and almost never in weeds.” So the next question is: “Sets in what?” We’ll commence with sand, partly because it seems likely that anchoring is done most often in deliberately-sought-out sand bottoms, but also simply because one must start somewhere and sand seemed like a good medium in which to launch a developmental learning curve. In truth, an experienced sailor usually looks for the kind of bottom in which the anchor he favors works best. It’s when he doesn’t find his preferred conditions that he is at risk. Designing The Test Wet sand just above the water’s edge is a difficult medium for an anchor to pierce; it’s much harder than sand under a foot or two of water. The rode, assembled with standard shackles, was a 10' length of 7/16" chain backed with line. The line was lead to a snatch block 10' off the ground level (on an 18"-diameter pole set deep in the sand) thence down through a block attached to a Dillon dynamometer and then to a two-speed, self-tailing Harken winch mounted on a fixed base. The arrangement permitted the repeated testing of each anchor in hard wet sand and in the water, at scopes of 3:1, 5:1 and 7:1. This was done simply by placing the anchors at either 30', 50' or 70' from the base of the pole. The three different scopes made the work time-consuming, but seemed necessary not only because of the varying claims made by anchor manufacturers, but also because, in actual anchoring, the available scope sometimes is limited. After setting up the apparatus, it was easy to place an anchor on the wet sand or in the water, in any configuration desired, stake its original position and measure where it “took hold” and engaged the sand sufficiently to resist a 200-pound pull on the line. Because of the difficulty of measuring under water, the figures were rounded at 6". We found that it matters not how most anchors land on the bottom while being launched. A good anchor cares not how it lands. The initial pull on the rode swivels or flops such anchors to the proper position. Because this was a test of setting characteristics, no attempt—other than a few deviations that seemed appropriate—was made to go beyond a 200-pound pull. That’s the pull that would be produced by a 30' sailboat anchored in sheltered water in 30 knots of wind. (For a discussion of “The Load On Your Rode,” see the July 1, 1996 issue.) Eleven Anchors In All Also included are several prototypes, both very promising anchors that their designers asked us to test. We’ll not name the prototypes because they are under development, are not yet on the market and, in this test, yielded results not equal to those of the best of the rest. To pre-judge them would be unfair. We’ll use photos and describe them, but call them “A” and “B”. In the process of testing, examining, experimenting, discussing and thinking about these anchors, we concentrated on the subject of how they set. However, it was impossible to reject thoughts about holding power, swiveling (or re-setting) ability and stowage. We also reviewed data from several of the prior tests identified earlier. Thinking just about setting, it appears without question that designing an anchor is not a simple matter. First of all, no matter how it is dropped to the bottom, the anchor must be capable of assuming its initial “dig-in” position. Further, its point or points must take an angle into the bottom. This “point presentation” is accomplished by a fairly large angle of attack (as in the case of the Bruce, Claw and Max), by a “heel” that heads the points downward (as with the lightweight types) or by weighting the point (as is done by the CQR, Delta and both of the prototypes). The latter suggests that the weight is only needed to help the anchor dig in, when in fact its purpose also is to shift the center of gravity away from the roll axis in order to force the point into the bottom. From a pure engineering standpoint, adding weight to get an anchor to set seems self-defeating. The end product of that line of thought would be a 500-pound pointed chunk of lead. But if a weighted tip helps an anchor dig in quickly and that anchor performs other functions in a superior manner, the weight would become tolerable. Whatever the design, one glaring, common conflict is that if an anchor is designed to go into the ground easily, it should have minimal cross-sectional resistance—which happens to be exactly the opposite of what an anchor needs to provide high holding power. We may later examine the “resisting plane footprints” or silhouettes of anchors. The Bottom Line The Bruce’s reputation for setting was enhanced by the Seattle tests, in which it set 97% of the time. Even in two rocky bottoms in which all other anchors had complete or unacceptable failures, the Bruce had a 100% record for setting. (Its closest competitor, a Max, set 65% of the time.) Besides Bruce and Max, in the Seattle tests, with their setting percentages, were a Luke yachtsman (14%), a CQR (63%), a Delta (57%), a West Marine Performance2 (65%) and a Fortress (59%). (The Claw, Digger, Danforth and two prototypes in our test were not included in the Seattle test.) (The rankings in the Seattle column on the chart were developed using data only from three test sites; not used were data either from those two rocky sites that some observers firmly believed were not proper anchorages or from the two veering tests, which failed to produce adequate numbers for anchors that otherwise appeared outstanding. If the bad site data had been used, Bruce would rank #1 on our chart under the Seattle ranking.) If one wants to carry an anchor that will set, with an insignificant percentage of failures, in any but the foulest bottom, a Bruce is the undisputed choice. That’s why it is a favorite aboard so many cruising and charter boats. But despite its excellent setting ability, in almost every holding power test the Bruce has been outdone by other anchors.
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