Hypothermia
In September 1999, British and Swedish scientists published observations about swimmers in cold water that are of interest to recreational boaters.
They found that the muscles of the arms and legs, especially the arms, became seriously weakened with prolonged swimming in cold water while the core temperature of the body was preserved in a normal range. It represents hypothermia localized to those muscles and not involving the vital internal organs.
They studied 10 competent swimmers of just above average fitness in their 20s and 30s. The swimmers were asked to work for 90 minutes in a flume of controlled current speed while being monitored for a variety of performance indicators. Water temperatures were 77F, 65F and 50F.
All 10 subjects completed the swim in 77 water, and eight completed the swim at 65. In contrast, only five of the volunteers completed the 90-minute swim in 50 water. The other five were removed from the water 22 to 61 minutes into the swim because they were unable or nearly unable to keep their feet off the bottom of the flume. At the time of withdrawal, mean rectal temperature of these five swimmers was 95F, not quite into the range of core hypothermia.
The approach of swim failure was marked by an increasingly upright angle of swimming, worsening coordination of effort and decreased efficiency (distance moved per unit of oxygen consumed). In 50 water all swimmers fingers were splayed and starting to flex, and all reported difficulty straightening their limbs. Their grip strength was only 74% of what it had been before the swim. Interestingly, grip strength was not altered by swimming for 90 minutes in 77 water.
The authors concluded that, in the ranges of cold water studied, drowning remains the major threat, since local muscle cooling impairs swimming performance and, consequently, the ability to keep the airway clear of the water.
For boaters on the usual recreational waters the study reinforces the basics: the man overboard needs flotation, preferably before going over the side, and may need major help climbing back onto the boat. Once the victim has flotation and is attached to the boat, the lethal effects of cold water are delayed for a while, allowing a deliberate and well-planned recovery.
Robert Croke, MD
Henderson, Nevada
No-Foul Transducer
For many sailing seasons I also had been plagued with fouling of my knotmeter paddlewheel. I solved the problem a couple of years ago by spraying the paddlewheel with a light coating of Tempo clear Outboard/Outdrive antifouling finish. It lasts all season. Occasionally I need to turn the paddlewheel sensor 180 but no longer need to pull it out and clean it every week or two.
Al Barry
Milton, Massachusetts
Otter Mischief
I’ve been following your bird wars series with keen interest as our local marina also has a droppings problem, but it’s from a landborne source rather than airborne. We keep our Skipper 20 at the Fair Harbor Marina, located on Case Inlet, a southern branch of Puget Sound in Washington State.
Seems that a family of river otters has made their home beneath some of the marina decks by burrowing into the Styrofoam deck flotation blocks. During quiet times they come out to play on top of the decks and, of course, inside the cockpits and on the cabin tops of some of the sailboats-ours included. As you can imagine, their bathroom habits are repulsive. They make bird droppings pale by comparison.
Fortunately, I found a relatively easy and, I think, environmentally friendly solution. After washing off the otter poop, I sprinkle a liberal dose of garlic powder on the deck right next to our boat. The little critters apparently don’t like the feel of the powder on their paws. They stop to lick it off, only to get a taste of what is obviously totally foreign to their otter senses. They beat a hasty retreat. One sprinkling lasts two to three weeks.
Bill Adams
via e-mail
Stripper Attacks Barrier Coating
Like many users of Peel Away “Marine” Paint Stripper, I’ve had very good results with the product. However, users should be cautioned (as the instructions do) to use it on a small test area first. When I first used it on a bottom that had been barrier coated with Interlux 2000, I was quite alarmed by significant softening of the Interlux 2000. After washing and neutralizing the stripped surface and allowing it to dry for a few days, the Interlux 2000 seemed to return to its hard state with no apparent permanent degradation, but for awhile I was really concerned.
Roland Borchers
Lake St. Clair, Michigan
Sav-Cote Teak Treatment
You finally discovered Sav-Cote products !
I have been using Sav-Cote products for the last 30 years. Their marketing was more towards commercial applications-big ships, water tanks, etc. The product was recommended to me by a boatyard when I had a strip-planked wooden boat that flexed too much to keep any paint on its topsides. The plastic-based paint, when dry, stretched to twice its surface without breaking. I used it on my boat for three years with fabulous results.
I then moved on to fiberglass boats, and then had to contend with the various teak surfaces on the deck and cockpit. I used Sav-Cote’s Teak Topcoat from then on, and I am still using it. It is the easiest to use-no sanding between coats, except to get a smoother surface before the last coat-and if you give it five to six coats it will last a long time and look good. In spring, I fix some abraded corners and other hurt areas, then I slap another coat on top of the existing coats and forget about it for the rest of the summer.
Fred Ploetz
San Diego, California
In our test of Sav-Cote Plasticlear, the test panel was badly checked after six months.
Good Seas Boots
In your February 1 issue, Nick Nicholson commented about the quality of sea boots. I have been helping a friend fish for halibut in southeast Alaska for the past six to seven years. During this time I have used a pair of boots by the name of Xtratuff. These boots are extremely popular with commercial fisherman and fish processing plant employees. I am very pleased with the boots and when the need arises I will purchase another identical pair.
The sole pattern is more open then recreational boots. This is helpful in preventing fish parts from getting wedged in the sole. Even with the unusual sole pattern I sill find them secure on a wet and or slippery deck. Seattle Marine (800/426-2783) has them for $53 a pair. They also have a great catalog.
Commercial fisherman work in all kinds of weather and use their equipment hard. I have found the commercial marine supply stores to be a great place to locate industrial strength products at prices often less than recreational quality.
I have enjoyed Nicks reports tremendously. It was an excellent editorial decision, in my opinion, to include this series in your publication.
Joe Cain
Oklahoma City, Oklahoma
Tether Tests
Aboard Mahina Tiare we use a high-lifeline system 100% of the time. We found having tethers attached to anything (webbing, line or vinyl-coated stainless wire) to be troublesome.
An alternative is using line (we use the same New England Ropes Sta-Set that we use for halyards) from the corner of the stern pulpit (pushpit) through an Alladin cleat secured chest-high on the inside of the upper shroud, and running forward to the bow pulpit. If the pulpits aren’t substantial, attaching the ends to mooring cleats is an option.
We supplement the high-lifeline system with five Wichard folding padeyes in the cockpit. This system allows us to clip into the high lifeline before leaving the cockpit, go forward, reef the main or whatever, and return to the cockpit without ever thinking about the tether. It slides along nicely and isn’t tripping us up by fouling around the ankles as is so common when going forward tether clipped to jack lines on deck.
If we need to go forward of the mast, we need to only unclip once, when passing the Alladin cleat, and then re-clip forward of the shroud. I haven’t felt a double tether was necessary since there are three shrouds plus the high lifeline to hold onto when unclipping and re-clipping, but I’m going to buy a double tether to try it out. If readers want to try this method, just lash a D-ring temporarily to your upper shroud, and run a dockline through. The key is to be on the inside of the shroud.
John Neal
Friday Harbor, Washington
Handrail Masking Tape Correction
We are so sorry for all of you who tried to order our Handrail Masking Tape (see Chandlery, April 1) through our web site. Its obviously not working. So we are going back to the old fashioned way-by mail or phone. Sorry for any inconvenience.
Judy Nelson
Nelson & Niemen Mfg.
6458 E. Marina Dr.
Long Beach, CA 90803
562/596-0104
Making It Stick
In the April 1 issue, you mentioned, in regard to the Davis Stick Bags/Pockets, that it was a problem getting the suction cups to stick.
When chartering, Ive often found it convenient to put up hooks and other items with suction cups, and likewise Ive found it difficult to get the suction cups to stick. Ive had very good success by smearing the cups with maple syrup. When the time comes to remove the suction cups, just pull them off, remove the residue with a wet finger, and then lick the finger.
Capt. R. J. Anderson
Freeport, Maine
More on Birds
After getting my new sail covers and dodger bombed by cormorants, we installed 50-lb. test monofilament line 6″ above the spreaders, stay-to-stay around the front of the mast. The birds must be able to have their chests overhang their perch; if they can’t, no perch is available. This has kept us clear of the pests for three years and works well with migrating birds down the ICW.
Our home anchorage in Massachusetts became a major roosting spot for cormorants. Some observations:
They do not appear to be afraid of any living thing. Mine stayed on the spreaders while we were on board. Animal figures are a joke. A lobsterman friend, utterly frustrated, shot one and hung it on deck. The next day his boat looked like the cormorant version of an Irish wake. No brains, no fear. At one point, our anchorage looked like a carnival with flags, nets, banners and such-the birds loved ’em.
The boats moored closest to channels where fish school seemed to have the worst problems.
Birds are very social. They always bring friends for a group defecation.
They are creatures of habit. If they can land once, they’ll be back!
Moral of the story, be proactive. Forget scaring them and expensive solutions. Just don’t provide easy landing sites.
Terry & Jeanette Sullivan
S/V Glass Slipper
BVI
TSRW Correction
The April 15, 2000 test of fiberglass restorers listed an incorrect phone number for TSRW. The correct number is 503/283-7006.
