Mailport April 2006 Issue

Mailport: 04/06

Mud Masters
Herewith some comments on your useful experiments concerning anchor holding power in soft mud as described in “Anchors for Muck, for Under 200 Bucks,” February 2006.

Holding power can generally be increased by deploying a heavier anchor. Heavy anchors are, however, otherwise undesirable. They make manual recovery more difficult and, when stowed near the stem, both increase displacement and reduce pitch frequency. So there is an obvious trade between anchor weight and holding power.

This suggests that some metric like the ratio of holding power to weight provides a better rating than simple holding power. Using this ratio, the Fortress FX-11 is the clear winner at 61, the [non-Fortress] runner up is the less expensive Danforth Standard at 28, and your starred Lewmar Claw is relatively poor at 19.

The poor performance of the CQR-type anchors brings to mind the comment of the cruising sailor quoted in L. Francis Herreshoff’s wonderful book “The Compleat Cruiser.” I can only paraphrase the old salt: The human race took millennia to develop a plow design that could be pulled easily through the earth, and some damned fool made an anchor of it.

The “damned fool” was, of course, the renowned British mathematician, G.I. Taylor. Fair winds and following seas.

Wm. G. Reinecke
Gloucester, Mass.

Our selection is based on the manufacturer’s recommendations for a specific boat and conditions. We’ve previously included the ratio you describe, and found these to be only marginally useful. The primary anchor is only a fraction of the weight in the whole anchoring system, and when the wind howls in the rigging, you’d be hard pressed to find someone complaining that their anchor is too heavy.


Reflective Tape Reflections
First, thanks for producing an excellent publication. With the endless marketing hype these days, it’s good to have someone on the side of the boating consumer. I am writing to you in response to the February issue’s article “A Shining Solution” about the Scotchlite Reflective Tape. I work for 3M at one of their plants located in Menomonie, Wis., approximately 60 miles east of the corporate headquarters in St.Paul, Minn. The plant where I work produces several of the Scotchlite brand of products, including the Scotchlite reflective material fabric.

The Scotchlite fabric is currently sewn into all forms of safety and outdoor clothing ranging from construction safety vests to reflective patches found on jogging shoes, sweat pants, and jackets. As an avid boater, I have often wondered why the marine manufacturing industry (especially the clothing and life jacket producers) hasn’t grabbed hold of the reflective materials available and incorporated them into their products? Certainly cost is no excuse when you look at prices of items currently produced. I also wonder why all the various buoys and markers that are employed on waterways do not have reflective markings. These buoys are there for one major reason: safety. Why not have them marked with reflective materials to make them 100 times easier to see with spotlights at night?

In the “S” section of 3M’s website,, you will find the various Scotchlite products (and descriptions) including the Scotchlite Reflective Fabric. Under the “Marine” heading Transportation Industry menu, you also find Scotchlite reflective products. You may also contact the 3M Personal Safety Products Department at 1-800-328-7098, or through the website.

Allen Wojcik
Menomonie, Wis.
Via e-mail


LED vs. Charts
The use of red, and to some degree green, light has been widely accepted and used in marine, aircraft, and other nighttime activities in order to protect the user’s peripheral “night vision” capabilities. Until recently, most red and green light for nighttime application has been produced by incandescent or fluorescent light sources; however, with recent improvements and an expanding variety of lighting fixtures, LED sources are becoming more widely used because of compact size, high brightness, very low power drain, virtual indestructibility, little heat, no UV, and long life up to 100,000 hours. Incandescent and fluorescent sources do not have a tight color spectral distribution that allows most all colors to be seen to one degree or another. LEDs generally have a very tight color spectral distribution, which in simplified terms renders colors matching the LED output color difficult to perceive. The color output of the LED is absorbed by like colors on the chart, or other object, and not reflected causing the eye to “not see” the color vividly. So the red or green LEDs will cause low visibility for red and green chart markings, respectively. A solution that I use is to mark over, with No. 2 black pencil, the red lines on my chart in locales where I will be navigating at night. For more information on color, spectral distribution, and LEDs a good Internet search engine will be helpful; I also have some more information on my website

Doug Archibald
Via e-mail


Chartplotter Report
When my wife and I returned from a bareboat charter in Belize and read your article on electronic charts (“Electronic Charts,” February 2006), it really hit home.

For navigation, we took along the Garmin 7.5 BlueChart that we had loaded on our Sony PC. This was hooked up to a GPS Map76 to plot the boat position relative to the routes that I laid out on the PC. In addition, we took along a GPS Map76CS onto which all of our routes from the PC are loaded as a backup and for use at the helm. Just before we left, I upgraded the operating system of the Garmin to Version 6.9.1.

Unfortunately we had a great surprise when we discovered that the new operating system no longer supported the GPS to plot the position of the ship on the PC with our new $150 BlueChart maps for this region.

This in itself would have been fine, but the route program always had the shortcoming of naming all of the waypoints with things like “33ft max depth” or “Chart US28162,” and this took up a large percentage of the small screen(1.5 x 2.5 inches). However, we could still download the routes to the GPSmap76CS and use this handheld chart-plotter.

As luck would have it, we chartered a great boat from the Moorings, a 38-foot catamaran built by Robertson and Caine in South Africa and sailed across the Atlantic. It was equipped at the helm with a Raymarine 530 with a C-Map chip.

We used this and compared it to the BlueChart maps that I loaded onto my little GPS. The route functions on the Raymarine with the C-Map were exceedingly easy to use (once an errant jib sheet was removed from the mushroom antennae) and it was a great replacement for my PC that no longer communicated with its GPS. I had the opportunity to compare both programs.

The BlueChart for this region was a good facsimile of the old Navy maps (supposedly updated to July 2005) and had a lot of detail regarding depth that was completely inaccurate. Twelve feet was as likely to be 65 feet and vice versa.

The C-Map was much less disconcerting to use since it didn’t show as much detail (as mentioned in your article) and mainly indicated when it was shallow or there were obstructions. However, both of these products had to be combined with hand-drawn maps that were updated by the Moorings from maps based upon the “Belize Cruising Guide” 1996 edition by Captain Freya Rausche.

On these charts, North was irritatingly offset by about 35 degrees to the left of up. At any rate, using the charting software and local charts, we were able to locate the cays (Lark, Rendovous, Queens, Ranguana) and still find a safe anchorage.

I was informed by the manager, Renee Brown in Placencia, Belize, that the Moorings are now installing Navionics chips in their Raymarine units consistent with your recommendations.

Dale Deutsch
Stony Brook, N.Y.
Via e-mail


In Praise of Dorades
The rusting process for Mr. Prysbylynsky’s tools (“Tool Corrosion,” PS Advisor, March 2006) began the day the designer or builder of his boat decided not to include dorades or equal.

One of the great unanswered mysteries of life is why otherwise knowledgeable designers refuse to include ventilation in their boats. Have they never spent a rainy three days cooped up below with the hatches closed? Or offshore with hatches battened? My 1985 Tartan has dorades.

My tools are Ace Hardware specials, 18-plus years old, with no rust. That the dorades work like a miracle, I proved to myself by shutting them one time when the weather turned cold and we were living aboard. I then forgot they were shut, left the boat for three weeks, and came back to a condensation-saturated interior, mold, and yes, rust on my tools.

A great many designers of very expensive boats should hang their heads in shame. Justice requires they spend the remainder of their lives cleaning up the mess they created and buying all their unsuspecting victims new tools.

Barrie Smith
Fort Myers, Fla.
Via e-mail


How Many Sinks In A Tub?
We feel obliged to report that “tubs” has not yet replaced foot-pounds as a standard unit for measuring righting moment. This and other errors appeared in a graph of stability curves that slipped into the March review of the Shannon Shoalsailer 35. The correct graph appears at right. (Bottom-paint testing, so it seems, does have its side effects.)


... Where Credit Is Due

Navman Service
I recently sent my Navman 3100 wind instrument in to see if it was reparable. The glass had been cracked, and the instrument was fogged and a bit erratic. To my astonishment, they treated this as a warranty situation and sent me a new replacement at no cost! I would have considered it more than fair had they simply offered to replace the piece at factory cost. Needless to say, I will turn here first for future electronics.

Henry Taylor
Westfield, N.J.
Via e-mail

Bass Products
Just wanted to recognize Bass Products for their help with my DC distribution panel. When I called about the backlighting for the panel meters, their technical service group was extremely helpful. They answered my call quickly, and researched my questions about power, bulb sourcing, and LED alternatives. They even tested an idea I had in their lab to see if I could make a change to my panel. They were extremely helpful and completely sold me on my first stop for future power needs.

Ron Hoofnagle
S/V Wild Rover
Via e-mail

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