Mailport 07/01/99


Keel Bolts
In the April 1, 1999 issue a reader asked about replacement of keel bolts. I presume, from his question, that PSs position is that the only way to repair a corroded keel bolt is to replace the keel. While I agree, crevice corrosion is of major concern on older stainless steel keel fasteners. Theyre actually studs, not bolts, most being made of the least noble marine stainless alloy 304/18-8. I would not agree, however, that the only solution is replacement…in some cases. We have successfully retrofit new keel fasteners by cutting a window in the keels side and then drilling down into it, then installing a 316 or Aquamet threaded rod, backing plate, nuts, etc. Some higher end builders use this system, Morris and Alden being two of them. With the cost of the average 40′ sailboat, 6,000 lb. keel at about $10,000, this seems like a viable alternative.

Additionally, you mention sealing the stub-to-keel joint with sealant and painting over it. It has been my experience that water will penetrate this type of superficial exterior caulking joint. The keel should be removed, the entire keel-to-stub joint filled with caulk (3M 5200 or equivalent), then replaced and torqued immediately. The sealant should NOT be allowed to set up. The torquing moment of a keel will squirt cured sealant out of the joint as soon as the boat heels. Finally, water migration into and around keel fasteners frequently comes from inside the boat, from bilge water. Accordingly, the sealant around and under the fasteners in the bilge must be renewed periodically, and the bilge kept as dry as possible.

Your publication provides a necessary service to the sailboating public. Keep up the good work.

Steve C. DAntonio
Manager, Zimmerman Marine
Mobjack Bay, Virginia

Teak Treatment Tests
After reading your article regarding Teak Shield and Super Shield, which we have been manufacturing for over 12 years, I felt that I had better write.

We have had our Teak Shield and Super Shield tested by the largest chemical company in the world, ICI. At two years, Teak Shield had only a 5% burn off and looked as good as it did when they started the test. It is hard to believe that in your test it only lasted a few months. We have been selling this product to Disneyworld for about 11 years and I doubt they would use our products if your test were accurate. It is possible that you tested the old product we previously sent you, but I think the major problem was applying only two coats of Teak Shield to plywood. We require at least four coats of product on wood and two on metals. This information was on a printed label on the side of the can on 1998 product. It might have been thrown out with the shrink wrap that held the crosslinker. We would really appreciate your doing a new test, following the new instructions.

We realize that you are giving an unbiased opinion to the best of your ability but sometimes mistakes are made and the results can be disastrous. Our Teak Shield and Super Shield are made from fluoropolymer, which is known to be the toughest and longest lasting product on the market.

Robert Dufendorf
Shield Products
Jacksonville, Florida

We can’t be sure about labels on overwrap, but the label on our cans of Shield and Super Shield called for two coats. As we said in the story, well be repeating the test following the revised instructions.

The March issue of Practical Sailor magazine interested us greatly as it reported your continuing tests of teak treatment products, including our Burgess brand water-based HydroGuard penetrating sealer-stain, rated Fair and HydroGuard over-coated with our HydroVarnish marine spar varnish, rated Good. However, the rating difference between the two treatments came as a surprise because year-long tests of the products in Key West, Annapolis and Marthas Vineyard, and over a decade of marine service in the UK, Europe, tropical climates, etc., show that both treatments give marine woods about the same degree of weathering protection

We suggest the test difference reported for our products probably arises from use of plywood as your test bed material vs. sawn wood on which our products are normally used in practice. Plywoods outer layers generally are of rotary cut peeled wood, producing a flat, closed grain surface as opposed to the open grain surface of sawn wood. The closed-grain plywood surface is considerably less absorbent than the open grain of sawn wood. This in turn prevents much of a penetrating stain such as HydroGuard to achieve its main objective of soaking into the wood to create an effective, lasting weather-resistant barrier. In contrast, film-forming coatings such as varnish, paint and layer-type stains act primarily by bonding to the wood surface rather than being absorbed by it. Therefore, on plywood, they can be expected to outlast penetrating stains.

Further, as you stated in your article, …film forming coatings do not adhere well to teak-an oily wood-(that doesn’t) promote good adhesion. This situation is, we propose, compounded when the teak concerned is plywood, for the reason stated above. Thus, when testing penetrating stains such as HydroGuard, sawn wood rather that plywood may well give more reliable test results.

Thanks for your continuing effort to evaluate and report on marine equipment and supplies. Its of great value to all of us in the boating community. Keep up the good work!

Ralph Meima, President
DERCO/Burgess Wood Treatment Products
Baltimore, Maryland

Hiking Sticks
On small cruisers, like the Rhodes 22, twist-lock hiking sticks are the only way to go. Firstly, they allow for sailing from anywhere in the cockpit with just a quick, easy, one-handed length adjustment of the extension. Secondly and more importantly, twist-lock sticks are the only type that, when snapped into a holder like the Rhodes 22s stern rail tiller locks, allow fine tuning of the tiller setting for Look Ma, no hands! sailing.

We hope your negative review of twist-lock hiking sticks does not cause Forespar to abandon this model (as they did once before, before bringing it back by our popular demand) leaving we hands-off-types sailing in circles.

Stan Spitzer
General Boats
Edenton, North Carolina

Glacier Bay Refrigeration
I was both amused and dismayed to see Steve Dashew make reference to his Glacier Bay refrigeration system (After 20,000 Miles, Part 2) in the May 15 issue. He states that while the refrigerator worked fine, the freezer was about 30% less efficient than we have seen in the past. He goes on to attribute this to either the Glacier Bay compressor or the lower efficiency of 134a refrigerant. While I have no doubt that Mr. Dashews freezer system does not perform properly, he need only look in the mirror to find the reason.

The fact of the matter is that Steve Dashew does not have a Glacier Bay refrigeration system or anything like it. While offering his technical critique of our equipment, he failed to mention a few rather important points. For example:

1. From the outset, he declined to install the combination of equipment that we recommended for his boat, insisting that he had done the calcs for himself and that he wanted a freezer that was warmer than the ones you would normally make for other people.

2. He did not install the factory Glacier Bay control unit for his system, choosing instead to design my own even after it was explained to him that the control system he proposed building would not work properly with our equipment.

3. He called me from New Zealand soon after his boat was built and asked me to help a local fabricator design new holding plates which he (Dashew) intended to fill with a solution he refers to as Tim and Arnies Superjuice. Given that I had tested this Superjuice earlier and found it to offer both mediocre performance and unacceptable toxicity, I declined to assist him. He then proceeded to build the special built-in holding plates he describes in your article. The special non-corrosive freezer solution he describes using in your article is also discussed and recommended in his popular cruising book in spite of its toxicity.

And so it is that the refrigeration system aboard Beowulf continues to fall 30% short of its owners expectations in terms of energy efficiency and freezer performance. I will consider this a professional credit since this is exactly the level of performance decline I had predicted he would suffer in my earlier conversations with him.

As for the noise issue, he is absolutely correct. Glacier Bay makes two 1/2-hp. DC compressor units. The Traditional belt-driven unit (the one Dashew purchased) and the MARK II. The former is noisier than the latter but it only weighs half as much. Those people wanting a very quiet system, who are not so concerned about weight, should select the MARK II, which is the quietest non-hermetic system on the market.

One might reasonably ask why Mr. Dashew didnt at least try the standard system we had recommended to him before seeing if he could improve it. Whether or not his approach to innovation is a good one depends on your point of view.

We at Glacier Bay and many others maintain that our DC refrigerator/freezer systems are the most energy efficient and temperature stable available anywhere. Since we all know talk is cheap, we have recently put together a program whereby potential customers can actually conduct professional-quality comparison tests themselves between our equipment and those of our competition. We are even offering a $5,000 cash prize if the competitors system should turn out to be more efficient. Those interested in more information on this program should visit our website at

Kevin Alston
Glacier Bay
San Mateo, California

Steve Dashew Responds: The initial installation aboard Beowulf consisted of Glacier Bay holding plates in the fridge and freezer, a Glacier Bay control system, and Glacier Bay compressors. When we were unable to get the Glacier Bay control system to work, in spite of numerous hours checking it out, we replaced it with one of our own, designed to a schematic supplied by Glacier Bay, and using Glacier Bay-supplied electronic thermostats. The rest of the components-relays, diodes and switches-were essentially the same as what Glacier Bay used.

Bilge Pump Cycling
Am I the only person who can’t figure out how to make two switches and a relay do what Paul Collins (March 1999) claims to have done with his bilge pump?

Steve Clarke,
Highland, Michigan

We made a modification to Mr. Collins schematic. Here, the relay is not energized until both upper and lower switches are closed. After its energized, it and the pump remain energized until the lower opens, regardless of the uppers position.

Practical Sailor has been independently testing and reporting on sailboats and sailing gear for more than 45 years. Supported entirely by subscribers, Practical Sailor accepts no advertising. Its independent tests are carried out by experienced sailors and marine industry professionals dedicated to providing objective evaluation and reporting about boats, gear, and the skills required to cross oceans. Practical Sailor is edited by Darrell Nicholson, a long-time liveaboard sailor and trans-Pacific cruiser who has been director of Belvoir Media Group's marine division since 2005. He holds a U.S. Coast Guard 100-ton Master license, has logged tens of thousands of miles in three oceans, and has skippered everything from pilot boats to day charter cats. His weekly blog Inside Practical Sailor offers an inside look at current research and gear tests at Practical Sailor, while his award-winning column,"Rhumb Lines," tracks boating trends and reflects upon the sailing life. He sails a Sparkman & Stephens-designed Yankee 30 out of St. Petersburg, Florida.


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