Mailport June 2004 Issue

Mailport: 06/04

One aspect of digital multimeters you did not mention in your April 15 article is their sensitivity to salt water. I had first-hand experience with this last fall, when enough water invaded my toolbox to rust out most of the tools. My Fluke Model 21, which has served me well for about 15 years, was included in this mess, and at first it appeared to be completely dead. With nothing to lose, I opened the case, replaced the battery, and gave the insides a thorough rinsing with fresh water. To my surprise, it came back to life, except that the zero setting was way off. After several days of drying out, however, the zero drifted back and the meter has been working fine ever since.

Fluke also makes a ruggedized Model 27, which they say withstands immersion to three feet for an hour. Though it costs over $300, it may be a good choice for wet environments.

-Jim Harman
Southport, CT


I readily agree with your pick for the best digital multimeter to have aboard. I have used Fluke meters for over 30 years and always found them several steps ahead of their competitors, especially in accuracy and reliability.

I might suggest a brief correction to the history of the DMM: it wasn't the advent of the LCD that created the modern DMM. It was the development of lower-cost analog-to-digital converter circuits. These circuits convert a voltage into a digital number.

I remember using Digital Volt Meters (DVMs) in the early 1970s that used neon indicator tubes to read out the voltage measurement ("Nixie" tubes). These meters were hardly portable, weighing maybe 20 pounds and requiring AC power to operate. They were bulky, but accurate.

The first portable, battery-operated digital multimeter used LED digit indicators in the early 1970s. The battery life wasn't great, and the meters were sometimes about the size of a small box of breakfast cereal, weighing at least one to three pounds. But you could haul them to a troubleshooting job without much trouble. In fairness though, you frequently had your faithful Simpson 260 analog meter in the trunk of your car—just in case.

By the late '70s, all handheld multimeters had converted to using LCDs because of the extremely low battery current needed to run these displays.

The high accuracy of modern DMMs allows the sailor to easily make the most important and frequent measurement aboard ship—that of lead-acid battery condition. A simple three- or four-digit DC voltage measurement after the batteries have "rested" for 30 minutes yields a high-confidence battery condition.

Thanks again for the DMM rundown.

-Al Carlson
Orange Beach, AL


Battery Monitor Interference
I read your article on battery monitors (PS April 1, 2004) with some interest. I agree that the Link 10 monitor has great functionality and is a good value. I have had some problems with them in one area that you did not test. All microprocessors radiate RF energy to some extent. Primary and harmonic frequencies can cover a broad spectrum. How "noisy" they are depends a lot on the quality of the chip and how well it is shielded. That is the issue that I have had with Xantrex. On one installation, I found that the Link 10 was radiating on four VHF radio frequencies to the point that they could not be squelched out and you could walk 40 feet away from the boatwith a portable radio and still pick up the noise.

I contacted Xantrex technical support and verified that the installation was correct (using the proper Xantrex cable, etc). In a conversation with a Xantrex engineer, he indicated that some of the microprocessors that they purchase are noisier than others. A tech support person also stated that most of the Link 10s are installed in RVs, where that is not so much an issue.

I returned the unit and they sent a replacement, which was an improvement, but still radiates on VHF channel 73 to the point that it can't be squelched.

My concern is that in most boats, the unit is mounted near the nav station where the GPS, VHF radio, and other navigation devices are located, potentially causing interference problems.

I am sure that this problem is not unique to Xantrex. It may be well worth it, for PS, to also evaluate other electronic equipment for such noise. I once had a Loran receiver that radiated so badly, that I couldn't transmit on VHF channel 16!

There are various specifications that most manufactures say they abide by. Using a spectrum analyzer, it would not be difficult to ascertain their level of compliance.

-Bob Kempe
Latitude 41 Marine Electronics


Bottom Paints
As always, I await your review of bottom paints [March, 2004]. This year what caught my eye was how well West Marine's CPP Copolymer Plus performed. I got out my trusty 2003 West Marine catolog. Sure enough, there it was, but the catalog price was $119.99 not $80.00. Oh well, you're just smart shoppers—I decided to wait until it went on sale. When it did, I went to my local West Marine and there it was on display, but wait—the label was different—same name, but it wasn't 55% CuOx, its 38%! Blast and damn! I asked the salesperson and he gave me an 800 number—800/221-4466. A nice lady answered, and said, "We didn't make West Marine CPP Copolymer Plus last year. We just put it out for them this spring. No I don't know what the Pettit name is for this paint."

Like I said, nice work on reviewing this year's crop of bottom paints. Now, where can I lay my hands on some old CPP Copolymer that hasn't gone stale!

-Marc Winder
Melrose, MA

Yes, the CPP Copolymer we put in the water in the spring of 2003 was made by Interlux. Our local West Marine manager tells us that there is, in fact, a decent inventory of the Interlux-made paint available, but we can't say yet how it compares with the new paint of the same name now made by Kop-Coat/Pettit.


I would like to offer an alternative opinion regarding your belief in annual bottom painting. I think it should be emphasized that when hauled each winter, multi-season paints, at least the one I used (Micron Extra, in which I have no financial interest) truly are multi-season. In 2000 I put a coat of black on, followed by a coat of blue with two coats of blue at the waterline and leading edges. Each fall, as close to haul-out as possible, I hose the bottom off, as opposed to power washing, which I think washes off too much good paint.

In the spring I go over the bottom with a medium abrasive pad on the end of a pole sander, which makes the job easy and fast, and then hose off again. According to the manufacturer, this removes oxidation and reactivates the surface. I repaint any areas where the black first coat is showing through, typically where the lifting straps were, and the keel, which was never properly faired and prepared. I think I lose more paint in the roller than actually goes on the boat doing these small area touch ups.

In the three years that I have done touch ups I have used less than a half gallon of paint as opposed to the almost three gallons that would have been required if I had painted each year. The boat spends seven months a year in the mid-Chesapeake, where barnacles encrust my prop, but the Micron keeps the hull clear except for an occasional barnacle in a spot or two. A brown growth does cover parts of the bottom, but no more so after four seasons than, I believe, it did the first. I think I could get a fifth season out of that one paint job, but rather than push my luck I plan to do an entire coat this spring, the first one since 2000. For the cruiser, this approach saves time, money, and copper load on the environment.

Thanks for a great publication.

-Brian Zeichner
Forest Hill, MD


This is to contribute a "point on the curve" regarding bottom paints. In May, 2001, I had two coats of Pettit Trinidad SR (red) applied to the bottom of my six-year-old Island Packet 350. Last week—two years and 11 months later—I took the boat out of the water to have the bottom painted again.

The bottom looked to be in very good shape, the only growth being on the metal around the propeller. I have had the bottom cleaned about every month during this time. I am a recreational sailor and keep the boat here in South Florida, where I do most of my sailing, mostly Biscayne Bay and the Keys, with an occasional trip to the Bahamas.

I enjoy your magazine. Keep up the good work.

-A.T. Kline
Miami, FL


Topside Paints
[Re: "Topside Paint Finale," January 15] I completely repainted a Catalina 27 10 years ago with AwlGrip, and have stripped over four coats of paint from an Islander 41 I'm rebuilding, as I'm repainting it with IMRON. I have some comments on your topsides paint test that I would like to share as well:

1. You can't separate the primer system from the paint or judge the quality of the two-part polyurethanes on one coat. They are meant to be built to a specific mil thickness.

2. I primed the Catalina with AwlGrip 545 primer and coated it with three coats (sanding between each coat) of Matterhorn white with Pearl Gray decks. It was a big job sanding between coats, but five years later, the boat looked just the same when I sold it to buy the Islander. AwlGrip was pretty difficult to work with (I rolled it on without tipping), but it held up extremely well. The roller left a "textured" finish that hid the imperfections well.

3. I put a quick, two-coat, single-part urethane (Pettit EasyPoxy) job on the Islander during our one-year cruise in 1998. I sanded the previous finish and primed it with Pettit's recommended primer. The Pettit was very easy to work with, flowed on great, and looked fantastic when finished—for five years. Now it is faded and has been stripped off to do the job right.

4. Around these parts (Oklahoma/Texas; up to 110° in the summer at Lake Texoma), IMRON 5000 is the paint of choice for the hull and other smooth areas due to its excellent durability and slightly flexible nature. One Valiant at the end of my dock was repainted with IMRON in 1990 and looked like new in 2003. AwlGrip is the paint of choice for the decks as it is less flexible, but more durable for the non-skid than IMRON. IMRON's primer system allows you to spray the primer, wait about 30 minutes, then follow with three top coats spaced out at about 45 minutes per coat. I did the entire hull in one day vs. five days plus sanding between each coat, as in the Catalina project. The IMRON flowed out perfectly even though this was my first boat to spray and looks like a mirror now. You could also tip and roll, but you couldn't get the four coats on in one day with that method, and you'd have to sand between coats.

5. If you are going to be doing as much prep work as is necessary to do the job right, it makes no sense to me to use anything other than a two-part system applied per the manufacturer's directions. All of them are probably pretty good.

6. A proper test (using the primer and at least two top coats) of Interlux, Awl Grip, IMRON, PPG, and Sterling would probably be valuable to your readers. This test would probably be a 10-year test, as all of them should look great one, three, and five years later.

Thanks for the great job you do. Many of your articles have been very helpful in choosing the right products for my Islander project.

-Steve Ellsworth
Via e-mail

Like the paint companies, we used single coats of all the paints in our topside paint evaluation, because of the unreasonably long time it would take to see results from a multi-coat test. As we noted, the single coats of the two-part systems looked a bit thin and transparent compared to the single-part paints after application, and even after a year, but after two years they definitely proved their mettle.


LED Dimming
Regarding your recent articles on LED lights, we've been working with LEDs for quite some time now. I think it's important to mention that LEDs decrease in brightness with increase in temperature. This is a non-reversible effect. It's best not to let multiple LED arrays stay on for more than 4 to 8 hours. We haven’t seen this effect with our 3-LED Crew-Light, but we have seen it withour LED19 cabin light replacement product and its competitive products as well.

Our tests have shown that "on times" of 24 hours or so build up enough heat to decrease brightness markedly with all 6- to 24-LED arrays we've tested.

-Nick Cancro, Sailor's Solutions Inc.
Northport, NY


Saving GPS Waypoints
[Re: "The Pull of Pushbuttons," April 1] Rather than re-entering all those waypoints manually, try this This site is for Garmin receivers, but Magellan may have an equivalent.

You should store your waypoints periodically, and never suffer the way you did by losing your GPS-memorized waypoints. I copy a file there twice every year, once at the end of our cruise, and again at layup. It only requires changing the interface from NMEA to your equivalent of "Garmin-Garmin," and no more worries about battery failure.

-Jim Martin
Via e-mail


GPS data can be backed up and waypoints can be entered using the appropriate serial cable and connecting the GPS to a Windows PC. The software I use is free and is by Topographics. Their website is

-Jack GaaschVia e-mail

Alas, The Magellan 2000XL has no serial cable input/output. It's all thumbs. However, those web addresses are valuable. Thanks for the tips.


Where Credit is Due
To Doyle Sailmakers, Annapolis, MD: "Last fall, Doyle Chesapeake Sailmakers in Annapolis, MD offered to wash, store, and check customers' sails for the off season for only $60. Today, I received a note informing me that my sails where ready to be picked up, and an invoice from them informing me that they had removed my genoa UV cover and installed a new one, as they felt the previous UV cover was poorly installed. Charge for repair—none. The repair was covered under their warranty. I never would have known I had a problem if they had not inspected my sail. It's nice to have a reputable sailmaker behind you." 

—Richard Paden, Columbia, MD


Since we published the May 15 "Weather Forecasting for Pay" article, the web address for NOAA's Ocean Prediction Center has changed. It's The changing of URLs in government web addresses is fairly frequent these days, as departments are being restructured. Some are now restricting access for security reasons; some are adopting "https" addresses, meaning "hypertext transfer protocol secure."

In the March 24 "Headings" article, we said that the U.S. Coast Guard deferred to states' requirements for the wearing of PFDs by children. The Code of Federal Regulations recently changed, and now requires the wearing of PFDs by children under the age of 13 aboard a vessel underway, unless they're belowdecks. The new regs do defer in the particulars to states that already require kids to wear PFDs, but takes precedence in states that have no such requirements.

The website of the Office of Boating Safety still does not reflect the change in regulations.

In the April 15 story on Ancor's Wire Tracker (part of "Digital Multimeters") we gave the wrong price for the Wire Tracker. The current best price online is $49.99, in several locations.

In the March Mailport, we quoted a wrong phone number for Royal Adhesives and Sealants, makers of Silaprene. The correct number is 800/999-GLUE.


Running Fixes
Running Fixes is a new department, in which readers can share information about competent people and worthwhile places they encounter in their travels—diesel mechanics and carpenters, riggers and painters, boatyards with reasonable policies and prices, well-stocked local chandleries, hard-to-find services, and so on.

Keep those tips flowing in. After we collect a goodly trove, we'll publish them, region by region.

Please send information by e-mail only. Write to us at, and put the words "Running Fix" in the letter header. And please, no commercials.

—The Editors


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