Stripped Hose Clamps
Re: The Case of the Stripped Hose Clamp in the September 1999 issue:
First, torque is not the issue. Clamping force is the issue. If your only measure of clamp performance is how much torque you can put on the screw you are missing the entire idea of what a clamp is and what it needs to do. Would you tighten a bolt on your engine until the head snapped off to ensure it was tight? You only do this with clamps because cheap clamps with poor clamping force have dominated the market for so many years that everyone is petrified that if they don’t “lean” on it, it won’t seal. If you measure a hose clamp’s performance by the torque you can apply to the screw, then there are a lot of rusted clamps with rusted screws that are going to “outperform” new clamps.
What you really want to know is how the torque that is applied gets translated into clamping force. Clamping force is the measure of the amount of pressure the clamp actually exerts against the hose to press it against the fitting to make a seal. You also want to know that the clamping force gets evenly applied around the circumference of the hose.
Second, design and material matter. Our AWAB 316 stainless steel clamp features rolled edges, smooth interior bands, and all 316 ss construction (including band, housing, and screw) for marine applications. We choose these materials and design features because our research shows that at the recommended torque they will provide more clamping force than perforated band clamps using lesser grades of stainless steel.
Third, follow the directions. Manufactures test their clamps in the factory and in the real world to determine the torque that should be applied to give the best clamping force, i.e. to provide the best seal. Exceeding the manufacturers recommended torque will not necessarily improve a clamp’s performance and may even damage the hose. This could lead to premature leakage and failure.
In conclusion, so you don’t have a torque wrench handy? With the majority of our clamps, recommended tightening torque can be achieved by using a screw or nut driver and manually tightening until it won’t go further. You don’t need to apply a leverage tool.
We will be glad to replace the clamps with which Mr. Harvie was dissatisfied and if he applies them with the recommended torque, we are confident he will be pleased for years to come.
Thomas A. Trzeciak
ABA of America
After reading your November 15, 1999 review of the Quicksilver QS-230 I feel compelled to give you some feedback as a former Quicksilver inflatable owner.
You mention that five air chambers “give it an extra safety margin should one or more tubes incur a puncture.” Maybe, maybe not. You should caution owners to periodically test to see if the chambers really stay isolated. Imagine my surprise when I opened one valve to deflate my Quicksilver 7' 6" Sport Model and watched all the main tubes deflate simultaneously. This boat was less than five years old and still within the prorated warranty period. Mercury Marine refused any warranty adjustment, claiming that the chambers were probably not inflated evenly, causing the failure of the internal bulkheads. I personally and exclusively inflated this boat for it’s entire service life, following the recommendation to inflate the chambers in stages to not stress the internal bulkheads. If the bulkheads can’t take differential pressure between chambers then how do they function as a safety item when one chamber is punctured?
In addition, your performance and handling concerns are indeed justified. I have witnessed two separate incidences of “nose-up backflip” of Quicksilver 8' 9" Sport models (now called the QS-270) in which the operator was ejected from the boat. Horseplay was not involved and the outboards were smaller than the recommended maximum.
My Quicksilver 300 was sold to me by my Catalina dealer for a substantially reduced price when I purchased my sailboat two years ago. I have used it for two summers with no cover.
The Quicksilver’s top surfaces became sticky this summer—adhesive enough to rip the hairs clean out of your legs. After cleaning and scrubbing the surface with detergents, spray cleaners, etc., which reduced adhesion temporarily, it became clear that this stickiness is a by-product of the boat’s deterioration in the sun. This dinghy is just two seasons old, and now the sticky areas have turned a rusty yellow-brown.
Just as we were going to press, Mr. King wrote to say that another Quicksilver dealer, Yankee Engine and Marine in Danvers, Massachusetts, replaced the entire “skin” of his 1997 inflatable. Cause was said to be “bacteria eating the soy in the UV protectant.”
I fully agree with your recommendations in the October 15, 1999 article on Peel Away Marine Paint Stripper. I have been using Peel Away for many years, and once I mastered the amount of stripper to put on the hull, according to the outside temperature, it has always worked flawlessly with excellent results.
The only problem I have recently encountered is the cost. Looking through one of my woodworking tool and supply catalogs I noticed they were selling Peel Away Paint Stripper for about a third of the cost of marine supply catalogs. Both products look the same, smell the same, work the same and have the same paper to cover the stripper. It all seems to be identical except for the word “Marine” printed on the more expensive version. Does the printing of the word “Marine” on the products container justify such a price difference, or is there something else to it?
AAU Marine Services
We also noticed Peel Away in the Woodworkers Warehouse catalog and have ordered a gallon. We’ll compare its performance with our “marine” version and report the results.
Life Jacket Bags
A recent PS article (October 1, 1999) noted that most of the lifejacket bags on the market are badly designed and don’t do the job. The Pegasus Project (www.nautilus.org) takes out up to 15 kids at a time on a 51-foot ketch, so we are very safety conscious. Having lifejacket bags that work is an important safety issue for us. After a year of frustration, we returned the West Marine bags that use Velcro to attach the lids to the sides. (The Velcro attached itself to the light webbing in the lid designed to vent the interior, effectively disabling the bag so that lifejackets and harnesses could easily fall out.) To give credit where due, West Marine—a sponsor of the Pegasus Project—credited our account fully nearly two years after these units were acquired.
But this left the practical problem of what to use instead. One of our crew suggested that we try the bags made by Carlyn Enterprises, 1207 Boston Rd, Greensboro, NC, 336/294-0290. Their stock number is 10200. As their pamphlet says, these are made of rugged white vinyl, with a heavy duty non-corrosive zipper, with top and side carry handles, extra sturdy seams, and are marked in red on the side “Life Jackets.” They are slightly smaller than the West Marine bags. They hold about four vests. What’s more, they cost less than those from West Marine.
A year and a half later, we can report the six bags that we use for lifejackets and harnesses are holding up well to intensive use.
We sail our Hunter 30 in Toms River on Barnegat Bay, New Jersey. The water in our marina is brackish but that does not stop the barnacles. I have been struggling to keep my prop and shaft free of these crustaceans for several years. While the hull never has any of these hitchhikers, the prop and shaft are always completely covered when the boat is hauled after our four-to-five month season.
I have tried several different approaches, including leaving the highly polished shaft and prop bare, coating them with wax, painting with bottom paint, and adding hot pepper to the paint. Nothing seemed to work. I don’t like the idea of removing my zincs and electrically isolating the shaft. This year I was successful.
Last spring, the shaft and prop were stripped of all old paint, buffed and polished clean and primed with two coats of Interlux 2000 barrier coat. I then applied one coat of Pettit Trinidad bottom paint. At the end of the season, there were no barnacles on the shaft and the Trinidad paint was intact. There were only a few barnacles on the concave surfaces of the prop blades, where some of the paint and primer had worn off.
Brielle, New Jersey
Black is Best
Nick Nicholson reports ultraviolet damage to the leech covering of a roller-reefing headsail (Offshore Log, June, 1999). Small wonder. White so-called “UV shield” Dacron is too often used on roller jibs, and was undoubtedly the leech tape that is coming apart near the beginning of his travels in the tropics. The “sacrificial layer of Dacron” he refers to will not be far behind. The coating (a white zinc compound) on this cloth extends its life about 20%. This sounds okay until you learn that tests show Dacron loses 40% of its strength after just THREE MONTHS in the Florida sun. Twenty percent longer than three months doesn’t even come up to four months!
Experience points to Sunbrella in the darkest colors (ubiquitous blue is good, but black is best) for roller jib and mainsail covers. For jibs, the cost will be slightly higher than for UV-coated white Dacron, and the result a little heavier, but the alternative is what Nicholson calls “a very expensive drop cloth.”
Dark covers will last at least twice as long as white ones, and will protect the sails under them much more than twice as well. Black polyester thread will last longer than white, and should always be used on covers. Even so, in low latitudes jib and main covers will need restitching at three- to five-year intervals. Eventually, even a dark cover will need replacing due to wear and tear, but the sail under it will often be nearly as good as new. Not so with a white cover. When it dies its early death, the sail under it is on its last legs.
It is hard to convince customers that when it comes to protecting sails from UV, black is best and white is worst. Some instinct seems to suggest the reverse.
“But isn’t white better because it reflects the sun?”
“Won’t the heat generated by a dark cover harm the sail?”
No, and no. The best practical test of the ability of a cover cloth to block UV is to hold up samples to the sun. If any light shows through, you can bet some UV is slipping through with it—visible and UV radiation are right next to each other in the spectrum.
In an earlier installment of Calypso’s log, Nicholson reported finding green mold in the roller jibs. Even without the photo, we could have deduced the white covers. He will never find mildew in a dark covered sail as the drying heat prevents its growth.
Wicomico Church, Virginia
Where Credit Is Due...
To Simrad, Lynnwood, Washington: “Two years ago, I installed a Robertson AP300X autopilot, partly reassured by your excellent review of the unit. While offshore this summer, it stopped working. Simrad’s service was great. With cellular phone calls to Seattle they diagnosed the problem as a faulty electric motor for the hydraulic pump. When we got ashore they quickly linked us up with an excellent service representative and supplied a new electric motor and hydraulic pump under warranty (which had expired a month before this incident). The service was as excellent as the autopilot itself.”
Bala Cynwyd, Pennsylvania
To Fujinon, Wayne, New Jersey: I would like to heap praise on the service at Fujinon. We purchased a pair of Fujinon 7 x 50 WPC-XL binoculars two years ago and have enjoyed their light weight and clarity. We also find the built-in compass invaluable when taking accurate bearings. While cruising the Western Caribbean the compass card came loose, the internal light failed and the caps were tearing. Upon returning to the US for a week-long visit we brought the binoculars to Fujinon for repair. Trish Plaskon of customer service took them in and had them fully repaired in a flash and with a smile.
Rob and Gem Schreiber
currently Rio Dulce, Guatemala