I read your steering compass review (August 1) and am writing to add some facts and pertinent information omitted regarding Plastimo and Plastimo compasses.
To begin, Plastimo International, S.A. is not owned by Airguide. In thepast, Airguide and Plastimo were both owned by Johnson Wax Associates(JWA)—now known as Johnson Outdoors. However, Plastimo stands on its own after being divested from the JWA group a number of years ago. Also, you state that only Nexus has a five-year warranty with all the others having three-year guarantees. In fact, all Plastimo compasses carry a five-year warranty, not three-years.
Turning to the test procedures part of your review, while we believe thetest procedures to be fair, the interpretation of the results needs furtherclarification. Plastimo compasses were ranked in the bottom third of your tests, based on your assumption that compasses displaying a higher degree of swing and longer settle time translate to lower performance. Thatassumption depends on what the intended use of the compass is. If we can agree that the primary purpose of a compass is to navigate accurately from point A to Point B, your assumption is invalid. Ultimately, the mostimportant quality of a compass is its ability to ensure that the steeredcourse is as close to your actual intended course as possible. In thisregard, a compass that has a higher degree of swing and less damping results in a course that is more accurate with less course deviation, albeit one that requires a higher degree of steering concentration.
Plastimo compasses are purposely built for accuracy by using weaker magnets, thereby naturally producing higher degrees of swing and less damping action.
Compasses that are built with stronger magnets settle faster and swing less, but can lead to wide course variations. This is because the stronger the magnet, the more the compass tends to point or stay to the North, masking the cumulative effect of small course deviations. Given two compasses used to navigate over a reasonable distance, the one which has weaker magnets will be more sensitive to course deviations, and thus be more accurate. In other words, after traveling five miles with a compass with strong magnets, the deviation of your steered course from your actual intended course will be far greater than if you had used a compass with weak magnets.
Steven E. Paley
President and CEO
MariSafe, Inc. — North American Distributor of Plastimo Marine Products
Mr. Paley, your statement that "a compass that has a higher degree of swing and less damping results in a course that is more accurate with less course deviation, albeit one that requires a higher degree of steering concentration," is interesting, as it brings into the equation the abilities of the helmsman, the sea state, and probably other variables that have to do with the boat's dynamics around the compass card—dynamics that other compass makers apparently seek to minimize. We'll ponder that.
I just received the October issue of Practical Sailor, with the article on in-boom furling. In general it is a good article, a lot better than the first one on the subject, back in 1998, but there are a few corrections to be made, and also in regard to the Hi Low Reefer, the author missed the point!
First of all, the first functional in- boom furling system to follow the Hood Stoboom was Sailtainer, also from Denmark. It was marketed in the US from 1986 through 1993. I was involved in it myself. The first Hi Low Reefer came out in 1990, and in 1999 the "new" design came out, similar to the one you tested (so it is not an old design).
From a design standpoint, John Mast has chosen a totally different approach than all others. First of all, keep it simple. Second, make it as close to a regular boom as possible, not looking like Park Avenue, or a big gutter. Big and bulky is not always better, and with more than 1,000 booms in service worldwide, I presume the system is working.
The author correctly mentioned the open slot in the boom, but did not mention that it is off center, which gives the sail a natural roll around the rod. At the same time, the upper part of the boom supports the rod, which is important with a large E measurement.
John Mast customizes the boom's gooseneck to fit the existing mast bracket, meaning no alterations have to be made—no holes, no rivets. The author also failed to say that three different mast track options are available— 1. the PVC/tube mentioned in the article, 2. an aluminum track, which is riveted to connector pieces slid up into the existing mast groove, meaning no drilling, no holes, no rivets (this track was on the Hunter 35.5 tested), and 3. an aluminum track with flaps to be riveted to the mast. This is used for very large masts, or older masts with external sail track.
How can you say that the Schaefer system looks like a promising unit for small to mid-sized boats, and talk about affordability—the Hi Low Reefer is far simpler and cheaper. The Hi Low Reefer is a simple solution for sailors who want in-boom furling and have boats between 25 and 40 feet. For larger boats we recommend systems like the Leisure Furl.
Bente Trading Company
Hi Low Reefer U.S.
The only thing that I can add to your excellent analysis of the Furl Boom installed on my Hunter Legend 35.5 are plaudits for the manufacturer.
I ordered my Furl Boom at the Fort Lauderdale boat show when it was first made available to the American market. The exclusive agent was Norseman Marine and the boom was called "Norseman Furlboom." Joe Brooks, the designer, was there at the time. I paid my deposit of $3,000 and waited. When I read about Norseman's bankruptcy I went to the telephone and found Max Hazelwood, who had been hired as a coordinator by the manufacturer to help solve the problems of the bankruptcy. What happened then amazed me. YSA authorized Hazelwood to hire the former Norseman head rigger (temporarily unemployed) to install the equipment, which was shipped to my home. All I had to pay was what was due under my Norseman contract, YSA eating the loss of the $3,000 downpayment. This was not the end of it. At the Miami boat show last February I ran into Brian Smith, VP of Operations at YSA. He noted that my boom had been delivered with gray sail covers, while Flyer is trimmed in navy blue. He sent me a new set of navy blue covers at no charge.
Butch Ulmer, my sailmaker, never expressed doubts to me about boom furling when I called him to discuss it. He sent my mainsail order to his UK people in Miami, Don Stagg and Mark Wood. They installed the sail and adjusted it for ease of furling. The six- batten sail has substantially improved performance of Flyer and has indeed extended the sailing time left to me as my 75th birthday approaches.
Robert N. Grosby
Fort Lauderdale, FL
Thanks for covering the subject of the effect of knots on high-modulus ropes (September). It's information that sailors need.
It appears that the rated strengths given for the rope you used might, in some cases, have been significantly different than the actual ultimate strength of the rope, and this difference could have skewed the test results. For example, the chart on page 19 of the September issue shows that 5/16" Maxi-Braid Plus has a rated strength of 5,700 lbs, yet the splice-splice break came in at over 9,000 lbs. If we assume a well-made splice weakens the rope by 10% or less, the actual break strength of the rope would be somewhere around 10,000 lbs. And if this is the case, all the figures for the knots made in that rope would be dramatically lower, in terms of percentage of break strength. So instead of the 59% strength that you show in the chart on pages 16 and 17 of the same issue, the bowline would have a strength of only about 33% of ultimate rope strength, which is in keeping with results we got from Yale, New England, and Cortland Cable.
Port Townsend, WA
Quite true—we looked at the knot failures in relation to rated breaking strength, not actual breaking strength, so you could say that our failure percentages look somewhat more forgiving than yours. We also had a couple of surprises, one of which was the splice-to-splice break in the 5/16" Maxi-Braid Plus, which came to 158% of the rated breaking strength of the line, and also the splice-to-splice break in 5/16" Aracom-T, which broke at 103% of its rated strength. Again, if we compare to an inferred actual breaking strength, the percentages would be closer to yours.
I was disappointed in your review and conclusions of the "high-tech rope"in the September 2001 Practical Sailor. You make much ado about the breaking strength of high-tech line once the line is tied with various knots. Your conclusion about high-tech line was that "...it can’t be a trusted mate on deck."
I think that you are missing the point: The breaking strength for high-techline of even the most modest line size far exceeds the normal application requirements on a sailboat, almost regardless of the knots used.
For example, the halyards on my Schock Wavelength 24 are 1/4" Yale Crystalyne (which has a vectran core and a polyester cover). This line has a rated breaking strength of 5,000 pounds. So what if a bowlinereduces this by 50% or even 60%? I'm still left with 2,500 pounds (or 2,000pounds at 60%) of "true" breaking strength. What load do you imagine I'm going to put on the halyards? I can assure you that it is significantlyless than 2,000 pounds! (I use a core-to-core eye splice for the YaleCrystalyne on the halyards, whipped, and stitched. I've been quite happywith this splice.)
I use 3/16" VECTRUS 12 from Yale as my backstay, leading to a 48:1 backstay adjuster for easy mast rake and bend. This line has a tensile strength that is higher than SS wire of comparable size, yet weighsa fraction of the SS wire it replaced. I use a core-to-core eye splice onthe Vectran, buried much deeper than called for, and whipped and stitched.
Racing sailors buy high-tech line for running rigging and sheets based on (1) line weight, (2) line stretch, and (3) line size. Weight (particularlyweight aloft) is important for racing. The line stretch is important tominimize sail adjustment based on wind speed differences. The minimum line size normally is the smallest line that can be tolerated for the expected application. There are other factors, of course (as outlined in your "Market Scan: Running Rigging" review) but I think that these three are the main factors.
Let's suppose that a bowline were used to tie sheets to the clew, for anyof the high-tech lines that you tested. Your test results showed that allthe lines held up past 2,500 pounds with a bowline knot, and most held uppast 3,000 pounds. This breaking point is past the maximum working load ofthe block through which the sheet normally would pass!
In any event, what sailboat application would place this high (3,000- pound) load on a 5/16" or 3/8" line?My point is that the rated breaking strengths for these high-tech lines isso much higher than expected stress for the application, that the breakingstrength is not really a consideration. This statement holds even if knotsdo reduce the breaking strength by a significant percentage (the clove hitchis excluded, of course, but I don’t know any sailors who would use a clove hitch to tie a sheet to a clew). I believe that most sailors can tie abowline to a clew using the high-tech line, and remain confident that theline will not break under jib or spinnaker stress. Certainly, the reduced breaking strength based on your tests does not warrant your "...it can’t be a trusted mate on deck" statement.
We're all for high-modulus line for shackle-ended and splice-ended applications like halyards and backstays, certainly on racing boats, and probably on performance-minded cruising boats, too.
Your point about the redundancy of strength in high-tech line, even when significantly weakened by a knot, is well taken. Still, we worry about the use of these lines on deck—in jib sheets especially, but really in any application where someone is used to tying a bowline or a rolling hitch in a piece of Dacron and expecting it to hold. In our tests we found the high-modulus line to be extremely slippery when knotted, and the only way to stop the slipping was to add more to the knots—and as we know, the more you add to the knot, the more you're likely to weaken the whole structure. Even with the redundancy, the differential between the tremendous potential breaking strength of a line on deck, and the weakness induced by putting a traditional sailing knot in it, is big enough to lead to a false sense of what's happening.
Your point that the breaking strength of some line is well above the working load of the blocks they're meant to pass through is... well, it's not a comfort, really, when we think of a sudden release of energy.
Also, some of the math is on your side, but some is not. See Brion Toss' direct responses to some of your points in Mailport Online on our website.
Again, high-tech line may work fine aloft, but at this point we just don't think saving a few pounds at deck level outweighs that worrisome differential, or, for that matter, the added expense—especially when you have to move up a diameter or two just to save the crew's hands.
You do justice to quoting Brion Toss, whose expertise includes splicing steel rigging, the finest combination of low cost and high strength. Brion has been rightly cautious of the modern materials, much as many trust only wood. high modulus fiber (HMF) ropes have to be treated as expensive space-age materials, and not like the inexpensive low modulus (and very reliable) synthetic fiber ropes, the nylons and polyesters. As your article emphasizes, knots detract from all their strengths.
While the modern HMF are ten times the cost, and de rigeur for the top-line racing yachts, they require both special fittings and proof testing. The one application long past due is to replace the stainless lifelines on the family yacht with their HMF counterpart, which is not a dramatic feature, until your heavy lightning storm. Otherwise, stay with what your sailor knows how to rig, and is most forgiving. The HMF materials have to be treated and tested as if they were exotic alloys of titanium or beryllium. Note that most fittings have not been designed or tested for the HMF applications. If you splurge on a Vectran halyard to reduce the stretch or creep, then beef up the shackle and clew, because the tensile load can get much higher, and possibly beyond the winch or mast design. HMF standing rigging is in vogue, but as a reminder, it is the hull at the mast step that takes the loads. Recall the scene in the last America's Cup that saw the graphite hull buckle , and the boat sink. Steel rod or HMF stays do not stretch much, while the graphite masts are great in compression, which calls for precise design, testing, and measuring. The ambitious upgrading may have fatal results, and always at the worst times, in storms and races when the stresses are greater than normal. HMF rigging can be very successful at the cutting edge, but careful safety factors have to be built in—but never with knots.
E. Pete Scala
Cortland Cable Company
A much longer version of Mr. Scala's letter, including a brief history of high-modulus rope and rigging (with footnotes, no less) appears in Practical Sailor's Mailport Online, in the "Rope and Standing Rigging" page.
Where Credit Is Due...
To Torresen Marine Inc., Muskegon, MI: "Over the last fewyears I've ordered two service kits for my Yanmar 1GM10 from Torresen because of their good price and their apparent expertise in diesels. The service kit contains, among many other vital things, a V-belt. When it was time to change the V-belt on my engine, I discovered with dismay that it was too short to fit. After e-mailing Chris Anderson at Torresen I learned that I had placed a wrong order (Yanmar changed the belt size in later models—when ordering one should indicate the model number). To my great surprise, he not only sent two free new belts but let me keep the old ones for some other needy Yanmar owner at my club. In all my dealings with Torresen I've received great service."
Charlottetown, PEI, Canada
To Westerbeke Corp., Taunton, MA: "In September I discovered that the 35B Universal engine on my 34-foot Catalina wasn't pumping water out of the exhaust. I immediately shut down the engine and determined the raw water pump wasn't working. I removed the pump and discovered the shaft to the pump was broken inside of the gear cover. I e-mailed Westerbeke (owners of Universal) and told them about my problem. They immediately gathered up the correct parts, including a sleeve that would solve this problem and sent them to my home at no charge. I was impressed. It was a much bigger job than I expected, but they were there for any questions."