Re: "Corrosion Inhibitors," PS May 1: After 13 years of living aboard I havedeveloped favorites in solving corrosion problems, and probably misused many as well. CorrosionX and Corrosion Block are both great products and have been used to temporarily solve electronic and electricalproblems until replacement can be completed. Best uses so far have been metal zippers, an internallygreen digital watch, and VHF handheld charger contacts—corrosion is resolved and prevented.
Corrosion testing on mild steel makes your comparisons easy. In the future could you consider some method of electrical properties testing?
While price per ounce on tested products in this article vary by about 4 to 1, these costs are minimalwhen a few squirts can save several hundred dollars' worth of gear and/or misery.
Another test I'd like to see is products to prevent the stainless steel screw and aluminum automatic welding. Over time I have used never seize-type products, 3M's 5200, Lanocote, and Tef Gel.
CorrosionX Max Wax will be tested on dinghy locks on board fairly soon. These locks tend to get a lot of salt water. I have been using numerous methods and found none good for more than a month or so.
It's articles like this one that can justify another year's renewal.
S/V Te Anuanua
I appreciate the strong position of Boeshield T-9 in your test, but wanted also to point out our product's versatility. It offers protection comparable to a "heavy duty" wax, the thin film and penetration of a WD-40, the ability to displace moisture and dissolve existing corrosion, and is safe for use on electronics. Our competitors offer three or more formulas to do what we do with one. We feel that with all of these properties Boeshield T-9 is the only protectant most boaters need.
-Peter M. Schwarz, President
I read your helpful article reviewing an array of corrosion inhibitors with interest. However, I am perplexed as to why you didn't review the heavy- duty silicone protectant products, particularly because they seem to do well on my windlass without leaving the yellow cast of the wax-laden products. Am I missing something here? Another great product that seems to be over-looked is INOX, marketed by INOX-US. This is a parafin oil product that appears to outlast the other penetrating products.
Los Angeles, CA
Leaky Tillerpilot Fix
I have had multiple autopilot failures due to water damage, and have come to the conclusion that the water enters the unit through the plunger seal. This has been the case on several different products. I have devised a cheap, effective method to diminish this problem: a long medium-to-heavy weight plastic bag with a diameter slightly greater than the diameter of the autopilot is passed over the fully extended plunger and the open end is taped to the body with 3M preservation tape, making a water seal. At the closed end of the bag, just proximal to the plunger end and the tiller ball fitting, the bag is tightly taped to the plunger and constricted, forming another water seal. The tiller pin fitting is then pressed through the plastic into its receptacle. The result is an inexpensive accordian seal which can be replaced anytime, anywhere, with spare bags and tape.
If the manufacturers of these units would admit to a flaw in the design, they could easily produce an accordian seal specifically for this purpose and in so doing have a much more reliable product.
Radios for SailMail
I would like to add to the Dashews' statement about the SGC2000 and Icom 706 radios ("After 38,000 Miles," March 2002). I installed both, for different purposes...
There are two reasons to have the SGC 2000. Most importantly, it's aneasy-to-use PhD (push here, dummy!) radio. In an emergency, any crewmember could use it, following the simple instruction card provided by SGC. This could be a significant safety factor. Secondarily, the SGC 2000 is an FCC type-approved marine radio. Both reasons really boil down to one: in order to be type-approved for marine use, a radio must be simple to use as well as comply with certain technical standards. The IC 706, although its technical performance almost certainly meets standards, is not type-approved for marine use.
I use my SGC 2000 for the marine channels—because it's there and it'sconvenient—and the IC 706 for ham radio, including accessing AirMail/SailMail.
I've used many radios in 50 years of ham radio. The Icom 706 is my clearfavorite for cruising. It's a miniature marvel that can do almost anything.Frankly, it's a fun toy as well as a tool. However, flexibility is a double-edged sword. The menu-driven bells and whistles of the Icom 706 arenot difficult to learn, but under the stress of an emergency a novice couldbecome dangerously confused. And it may be the captain who has goneoverboard or is incapacitated.
Regarding Dashew's complaint about frequency stability, the SGC-2000 is not a "quick warm-up" radio. For best stability its temperature controlled crystal oven should be left permanently on, even though this results in a small battery drain. Starting with a cold oven, inaccuracy and drift of atleast 100Hz and perhaps 200Hz or more, depending on the operating frequency, may be expected during the first few minutes. This is too wild for Pactor. The initial inaccuracy and drift of the Icom 706 are comparable. Both the SGC 2000 and Icom 706 should be warmed up for at least 10 minutes before attempting an AirMail/SailMail connection. It's possible that the initial warm-up drift of the SGC 2000 might be a little worse than that of the Icom 706, but after the warm-up period the SGC 2000 with its temperature-controlled crystal ought to be more stable than the standard Icom 706. Perhaps Dashew's unit was defective in manufacture or materials.
For AirMail/SailMail I recommend Icom's optional temperature-controlledcrystal (Icom high-stability crystal unit part number CR282). This miniature "oven" is so small that it warms up fast, giving the 706 rock-solid frequency stability very shortly after turn-on. But unless you're a die-hard expert,have it installed by a factory-authorized distributor (and not by your localmarine electronics handyman; this is surface-mount technology).
I also recommend the optional 500 Hz filter (Icom p/n FL100). This filtersout interfering signals on nearby frequencies and is easily installed.
-Robin C. Moseley
Pitted Iron Keel Advice
Re: PS Advisor, May 1: Please allow me to offer the URL to my website. If you follow the link, you will find the page which describes the process my friend and I went through to refurbish my Ensenada 20's badly pitted and rusted keel. We found lots of good information on the web, and wanted to add our experiences to help those who were considering doing this to their boats. The URL is: www.dcwi.com/~nybarra/keel.html.
Your advice was right on the money, as far as it went, and was how our keel was prepared about eight seasons ago. Each spring, I've had to touch up increasing levels of rust and it looks like I'm going to have to repeat the messy, expensive procedure next haulout, as I noticed some fairly big rust flakes under the barrier coat this time.
A favorite topic on the Tanzer newslist has been how to keep the rust at bay and we think we've found the missing step: slowing down and maybe stopping the rust when the barrier coat starts breaking down. POR-15 and the companion Metal Ready treatment is the current best we've found. Metal doesn't have to be bright, just no loose flakes. Indeed, one report indicates it works better if there's a little rust for it to bind to. Last I heard, the early adopters were going six seasons without any rust. Pettit's RustLok is a distant second, but is better than nothing.
Mixing Batteries, Continued
There is additional important information to consider regarding the problem presented in the letter from Klaus Schaefer in the PS Advisor section of the May 1 issue about his plan to connect different-size batteries in parallel. First, the worst outcome occurs when one battery develops a shorted cell while connected in parallel with another fully charged battery. The resulting current flow can be high enough to cause the acid in the badbattery to boil and gush out. This danger can be avoided by fusing theconnection between the batteries.
The battery combiner, sold by West Marine (page 590 of the 2002 catalog), and perhaps others, is essentially a relay that can be connected between two batteries, which closes when the voltage of one exceeds 13.3 volts, which only occurs when it is being charged. Thus, the batteries can be automatically connected in parallel when being charged, but not at other times.
In reality, it is not complicated to compensate for the voltage drop across diodes used to isolate batteries. The key is to connect a diode identical to the ones used to isolate the batteries in series with the wire through which the voltage regulator senses battery voltage, which is easily done with an external regulator. I have had such an arrangement on my boat, which has three batteries connected as three separate banks, for the last nine years, and it has worked very well. The diodes I use on my boat are rated at 35 amps and cost about a dollar each as industrial surplus. These diodes are adequate because I have no single battery that can accept 35 amps. My diodes are mounted on large homemade aluminum heat sinks.
When installing such a system, it is easy to connect a second diode and a switch, providing the choice of having an additional voltage drop, so that the regulator senses a falsely low voltage. When the alternator output is not the maximum for the rpm, this makes it possible to increase the charging rate.
With either of these systems for allowing batteries to be charged inparallel automatically without taking the risk that they will discharge intoeach other, it is, of course, necessary to have at least one battery switchfor each two battery banks. I had to install an additional switch when Iadded my third battery, but I do not consider this a disadvantage, because I would not be comfortable with a system that would not let me easilydisconnect any battery.
Little Rock, AR
(Re: Mailport exchange, May 1) I was a paint maker for a number of years and I must tell you that paints from the same manufacturer can vary with batch.
Paints are made in batches from 200 gallons to 1,000 gallons or more. This is done to keep the product fresh and to meet the needs of the retailers.Paints do deteriorate and become less effective over time. Paint factories test each batch made for consistency to an internal standard as determined by the chemists. This is necessary for a superior product but elements can creep in to make batches vary. A new paintmaker or chemist, changes in testing procedures and, most likely, changes in the chemistry of the chemical supplier's products. Paint factories depend on the consistency of chemical suppliers for the product quality too.
Superior paints will out, over time, and one test will only tell you aboutthat one batch. That is why testing each year by Practical Sailor is soimportant and also why subscribing over the long term will provide the most practical information.
-David L. Williams
Starring the Understudy
A reader who ordered the Seafit Deluxe Boatyard toolkit from West Marine after reading "Off-the-Shelf Marine Toolkits" in our March issue was puzzled to receive a kit with the same name, but with different (and apparently inferior) tools.
We checked with West Marine. It turns out that at the time of our review, West was out of stock of the regular kits, and was filling orders with substitute kits. These kits, sold under the same name and parts number, did contain tools of a better quality than the standard set. As luck would have it, it was one of the stand-in kits that PS reviewed and commended. They were indeed a cut above the crowd—they just weren't here to stay.
West Marine sends along apologies for the confusion.
Although PS chose that stand-in kit, and one from Sears Craftsman, as good bets for pre-packaged tools, we also tried to stress the idea that, unless you're in a hurry, buying by the kit is no way to go. Take your time, target your needs, get good tools, and stow them your own way.
Where Credit Is Due
To Sailomat / Davids Cruising Systems, Richmond, CA: "Although we've had our Sailomat wind vane on the boat for three years, it's been little used so far because we seem to have spent most of the time motorsailing upwind. Recently, given the opportunity to use it, we were having a heck of time balancing the unit as specified in the manual and every article we could find about sailing with self-steering. When we asked for help from the US representative, Greg Davids of Davids Cruising Systems, he relayed our query to Stellan Knoos, the designer and builder of the Sailomat (with whom we talked at length before purchasing the unit). He determined that the air vane we had been sent originally was too heavy, and authorized express shipping to us in the Cayman Islands of a newly designed vane, at no cost to us. Their immediate and positive responsiveness to our problem reflects the best one can expect in keeping a customer happy, and we commend their willingness to stand behindtheir product!"
-Jim and Katie Coolbaugh
To ACR Electronics, Ft. Lauderdale, FL: "I purchased an ACR 406 EPIRB in 1996. It came with a free battery replacement certificate that expired sometime in 2000. Due to circumstances (a job) we stopped cruising in 1998 and stored our boat on the hard, including the very valuable certificate, a continent away. We started cruising again this spring and came across the expired battery certificate. When I called them, ACR immediately agreed to honor the certificate and we have received, postage paid both ways, the upgraded EPIRB. I would like to express our appreciation to ACR for great customer service.
S/V Escape Key
In the "Certifications and Ratings" article, May 15, we referred to UL as United Labs. It's Underwriters' Labs, of course.