Bare Feet vs. Boat Shoes Your article on men’s and women’s boat shoes was very informative, and for reference, I would like to see the wet and dry grip angles for bare feet, which many of us "use" during hot weather. Rob Ransone
Chesapeake Bay, Va.
Bare Feet vs. Boat Shoes
Your article on men’s and women’s boat shoes was very informative, and for reference, I would like to see the wet and dry grip angles for bare feet, which many of us "use" during hot weather.
We subjected some volunteer bare feet (and the individuals to whom they are attached) to the same test used in the comparison of men’s and women’s athletic-style boating shoes (June and July 2007, respectively). On average, bare feet gripped as well as the top performers in our shoe test: Bare feet lost grip at a 35-degree angle on fiberglass (wet and dry) and 40 degrees on teak (wet and dry).
We suspect the "grippiness" of bare feet can vary greatly according to each individual, so these conclusions probably cannot be applied broadly. Several readers also inquired about other style boat shoes, including sandal-style and the familiar Sperry Topsider moccasin style. We will compare those in future tests.
Vertical Wind Turbines
I am reading with great interest your very well written article on wind turbines in the June 2007 issue ofPractical Sailor, and want to make sure that you are aware of another type of wind turbine that does not employ blades, but works on a vertical axis principle. While somewhat more costly than the traditional types, the maker claims there are numerous advantages (especially for boaters) to this design, some of which include: less noise (vertical wind turbines produce 0 db of sound); more efficient (vertical wind turbines begin to produce electricity at 3-6 mph of wind); less dangerous (vertical wind turbines have no blades); greater ease of installation (vertical wind turbines do not require the horizontal space turbines with spinning blades require); less harmful to birds (birds perceive vertical wind turbines as solid objects and do not fly into them).
The current higher price will be mitigated somewhat in the future when the vertical wind turbines are manufactured in the U.S. At present, they are manufactured in Europe.
I hope that in a future article, you will be able to review this type of wind turbine and compare it to blade versions. A link to one brand of such turbines is:
We consulted James Johnson, the senior mechanical engineer at the National Wind Technology Center on this topic, and here was his take: "From an aerodynamic perspective, a nearly pure drag device [such as this] cannot come close to other types of lift-generating wind devices used to make electricity. It may be relatively quiet, but I guarantee that it makes sound, all wind machines do, especially drag devices... Drag devices start easily in low wind speeds, but generator output, if any, is very low. There just isn’t enough energy in the really low wind speeds for any machine to make much (or any) power... We’ve spent several million dollars over the last 10 years looking at avian interaction with wind turbines, and there is no scientific evidence that birds don’t fly into things that they can see, partially see, or not see at all. This type of wind generator may work fine to produce a small amount of electricity to keep batteries charged. The thing to look at would be a published authenticated power curve (power output vs. wind speed). That and cost are the most general way all wind machines are compared.
I’m redoing my teak rails. I intend to use varnish to refinish. A fellow boatowner suggested when I get down to the bare wood, I should use a "penetrating epoxy" after sanding and before applying the varnish. He said it will prevent moisture, the culprit in deterioration. Is he right?
Chula Vista, Calif.
Teak does not like nor need to be epoxy coated. Its high oil content both protects the wood and can cause adhesion problems if epoxy encapsulated. Epoxy rot treatments are not intended to be primers for varnish. Not only do they make an inferior substrate for such a purpose, but when it comes time for removal, the process can be daunting.
As a metallurgist, I wish to comment on your article regarding immersion testing of mooring chains ("The Crusty Proof," July 2007). I do not believe the slight staining will affect the performance of the AISI 316L alloy. Had the chain been fabricated from AISI 304 stainless, crevice and pitting corrosion can be experienced, particularly with welded non-stabilized alloys.
Use of chain made of stainless steel that is inferior to 316L is flirting with possible disaster. The consequences of chain failures can be very costly, since they frequently occur when the boat is unattended.
In addition to normal corrosion that occurs in aerated or still salt water, fretting corrosion is also a major concern. Fretting corrosion occurs when the chain links rub against one another, removing, in the case of coated chains, the protective zinc coating rather rapidly. This results in relatively high rates of corrosion. Stainless alloys resist normal corrosion through the formation of a thin layer of protective oxides that form naturally on the surface.
When immersed in a corrosive medium like salt water, this oxide film forms at high initial rates, then drops to near zero when the oxide thickness reaches a value where oxygen can no longer reach the metallic surface. Fretting at contact points can remove this coating, resulting in higher rates of oxidation and increased loss of material.
Your upcoming test where the chains are suspended with an applied load should prove interesting. One caution, having the various grades of chain in contact with one another can produce skewed results. Stainless alloys can corrode more rapidly when in contact with carbon steels. Mutual contact between the carbon steels may also mask individual corrosion performance.
Dr. Charles F. Barth
Field Report on Waeco 52
Unfortunately, your articles about portable refrigerators (Practical Sailor April and May 2007) are too late to help me. I bought a Waeco 52-quart portable refrigerator several years ago for my older Bristol 35.5. I chose a portable refrigerator because rebuilding the ice box and cabinetry for an efficient built-in was going to cost me many thousands of dollars. For my boat, I think I made the right decision even without considering the cost difference.
The unit doesn’t use much energy. We’ve spent the past two years in the Sea of Cortez. With two 85-watt solar panels, we can be at anchor indefinitely without running the engine. The portable unit allows us to turn the former ice box into a large storage area, a real boon on a small boat.
The best that I can figure is that the control unit adjusts the temperature in 8 to 10 degree increments. We set our unit so that the bottom is about 32 degrees and the top is around 40 degrees. The side pocket, which we use for beverages, is somewhere between 45 and 48 degrees. At this setting, we can keep meat almost frozen (almost) on the bottom for five days.
I might have purchased another unit if I had read your article first, but so far, I am very happy with the Waeco.
Although a well-insulated built-in box will be more efficient, these portable compressor fridge-freezers offer a quick, hassle-free way to add a fridge or even a freezer on a boat that lacks one. We were able to freeze water with all of the units we tested. Several readers who use these units recommend that a folded towel over the lid-top helps improve efficiency.
Glacier Bay on Propulsion
As a staunch environmentalist and the founder of a company focused on developing environmentally friendly marine products, I welcome the discussion of the potential fuel efficiency afforded by the move to diesel-electric propulsion ("Propulsion of Tomorrow," July 2007). The potential for savings is real, and we typically expect a reduction of around 30 percent for most users of our OSSA Powerlite system. Nevertheless, I am concerned about the intense focus this subject is beginning to garner.
I am increasingly seeing even well-respected marine technical writers trying to simplify a fuel efficiency comparison. The only way to compare the fuel efficiency of different electric systems with each other, or electric systems with conventional systems, is when referenced to a standardized course. The same is equally true of cars and home refrigerators. Otherwise the EPA could simply publish the fuel efficiency of a particular engine or electrical efficiency of the refrigeration compressor used in a given model. On our website is a paper that explains that the potential to obtain superior fuel efficiency with electric drive must be viewed in light of the performance of the fully integrated system, not simply a tally of losses at a particular engine load.
My second concern is that all this concentration on fuel efficiency misses the big picture of the advantages gained with electric drive. When Toyota decides to move its entire product line to hybrid-electric propulsion (they started with the Prius), better fuel economy was not the main reason for doing so. Rather, Toyota recognized that conventional technology had reached the limit in its ability to provide a superior user experience without increasing cost. Moving to electric drive changes the equation at a very fundamental level. Freed from the constraints imposed by conventional drive systems, innovative designers now have a path to creating vehicles that are quieter, more comfortable, safer, more reliable, better handling, more convenient, cleaner and, ultimately, cheaper than would otherwise be possible.
Founder/CTO Kevin Alston
Glacier Bay Inc.
The "No-Bake" Oatmeal cookies [with raisins and nuts] in your July editorial ("If You Can’t Take the Heat . . .") sound like a wonderful addition to a long cruise. However, your directions did not use all of the ingredients! You only used the first four ingredients; you never used the peanut butter, vanilla extract, nuts or, most importantly, the oatmeal!
Arnold M. Flank
The editor’s ineptitude with all things cooking-related apparently extends to the editing of recipes. With all due apologies to his long-suffering wife andPractical Sailor readers, Theresa’s recipe (adapted from similar recipes from various sources) for No-Bake Oatmeal Cookies is reprinted at right.
Two Burners are Enough
Regarding your recent test of three-burner stove ovens, you really don’t need more than a two-burner stove. Also, it is important to see how much space there is between the burner and the stove’s sea rail to make sure your pots fit centered over the burners.
Corinne Kanter, Author
Try a Tasco
I read over the article about sea-going galley stoves with great interest. I have cooked across a large portion of the Pacific using a Force 10 stove, and frankly, I’m not sure that I would cook on one, willingly, again. I ordered one for my own boat and was very dissatisfied with the quality of the construction, the fold down/fold under door, and the height of the sea rail. In fact, one Force 10 salesperson told me that if I needed a proper sea rail, I shouldn’t be cooking. (There have been times when I’ve wholeheartedly agreed, but I still had to cook).
It would have been nice to include whether the insulation is sufficient to keep the outside of the stove reasonably cool. In practice, I found that the Force 10 got hot enough on the outside of the oven to burn the cook. Another feature that I found troublesome is that if you have something cooking on the top of the Force 10, you have to either move it or hold it on while you open the oven door, or you could end up with a lot of something boiling down your front. This can be a problem with all stoves, but with the Force 10 this issue is intensified because the door slides under. And yes—as the testers pointed out—you can unlock the door all too easily. Even a good bounce off a wave can do it.
West Tisbury, Mass.
All of the stoves fell short of our ideal, but we yet hold hope that Tasco, Force 10, and others will yet come up with better ways to meet the cooking needs of the cruising sailor.
As described in our stove review, in addition to liking the Force 10, testers found the Tasco to be a very practical unit with many of the features we liked. The excellent sea rails, large oven, and efficient stovetop burners scored highly in the comparison, and sailors who value these features should not overlook the Tasco as a viable option.
Testers did check temperatures on the outside surfaces of each stove when it was heated to 350 degrees F. The Tasco was cooler at the front (83.3 F), by about 2.5-degrees F, than the Force 10. Only the front of the Origo 6000 was noted as being "too hot to touch."
I just picked up a Weems and Plath Mini Yacht Lamp, and Weems and Plath recommends its brand of fuel. I recently read somewhere about a lower-priced alternative. Any suggestions?
Humboldt Bay, Calif.
Your Weems and Plath Mini Yacht Lamp will burn on a wide variety of fuels, but it is primarily meant for use with highly refined kerosene (also called paraffin). Generally, highly refined or "pure"paraffin such as the Weems and Plath potion ($35 a gallon at West Marine) burns cleaner and has less odor than the much cheaper option, low-sulfur kerosene (K1 grade) that is used in some kerosene heaters and is also used in oil-burning lamps. We presume that some of the many other brands of lamp paraffin available at major retailers, candle stores, chandleries, and the Internet will burn as clean as the Weems and Plath variety, but have not tested this. If there is a reader who is happy with an inexpensive, clean-burning lamp oil, we’d like to hear about it. As is the case with all fuels, you’ll get a better price buying larger volumes.
The editor lived quite happily for many years using mostly low-sulfur kerosene in his Weems and Plath lamps. Yes, soot buildup and smoke stains were problems, but regular cleaning, and keeping wicks clean and trimmed helped minimize this. Not surprisingly, the closed-type "hurricane" lamps like the Mini Yacht Lamp seemed more susceptible to soot buildup than open-chimney type lamps. One chief difference between highly refined "pure" lamp oil and K1 grade kerosene is that the paraffin will gel at about 40 degrees F, while you can still pour kerosene at below-freezing temperatures. Otherwise, the choice between lamp fuels like the Weems and Plath oil, K-1 kerosene, or any of the other suitable fuel, depends on availability, your own threshold for odor and soot, and what you’re willing to spend. If there is enough interest in this topic, we could certainly compare lamp fuels and costs.
In regards to your recent tether review ("Sailing on a Short Leash," January 2007): When I tried to purchase the recommended West Marine tether with Kong Tango clips, West Marine was back-ordered for weeks on tethers.
So, with my summer cruise approaching, I got a little desperate. During a late-night Google session, I found a tether being sold by Defender Inc. (http://www.defender.com/ ) that turned out to be an absolute winner. It is a dual tether with elastic stretch and a safety hook (product number 000272). It is actually manufactured by Kong, Italy (http://www.kong.it/). The Kong carabiners are things of beauty. They are lightweight, extremely well built, and do not leave any marks on the topsides as they shuttle along the jacklines. I am tempted to buy a few of them to play with at the office, they are that cool.
The other great thing about this tether is it is being sold for $100, $50 less than the West Marine version.
The Kong tether as a whole is an extremely robust build. Also, one respondent to your review stated that the double tether was a pain, and inevitably one leg or the other had to be cut off or taped. I single-hand my Freedom 30 and use the long leg in the cockpit where I clip into a deck pad eye and the short leg to go forward on the jacklines. There is just enough stretch in my configuration to allow me to stay clipped in while I switch from one to the other. It worked out perfectly.
Regarding what to do with the unused leg: The Kong Tango carabiner has a tapering hook end. There is enough room on the tether side of the quick release shackle to allow the unused leg to be clipped into it.
This puts it completely out of the way (even the long one) and does not interfere with the operation of the quick release in any way.
I believe that folks should get in the habit of setting their quick-release lanyard on the same side all the time. In a stressful situation, you should know where your quick release is.
Stockton Sailing Club, Calif.
The president of Container Yachts is Bernie Blum. His last name was misspelled in our review of the Far Harbour 39 in the July 2007 issue.
Titanium dioxide and zinc oxide used in sunscreens are inorganic compounds, contrary to what was stated in the Mailport section of the August 2007 issue.
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