Mailport January 15, 1999 Issue

Mailport 01/15/99

Hydraulic Propulsion
A copy of your (Charles Kanter’s) letter to PS (August 1, 1998) condemning hydraulic drives as a viable propulsion system came to my attention. You listed your qualifications as a marine surveyor and a delivery captain, but I failed to see any certification as a hydraulic engineer. Your lack of expertise in this subject was obvious by your groundless, irrational attack.

One of your experiences was dated “Circa 1970.” Hydraulics, like almost everything else, have undergone a bit of refinement in the past 30 years. I shall address your points:

Hydraulic motors and components are available in aluminum for aircraft use and hoses and fittings can be stainless steel (non-magnetic). No magnetic interference, no corrosion.

Hydraulic motors need not be heavy. In a twin cat installation, a single spare motor would serve either port or starboard. A reversible motor would not require any control other than a Morse or Teleflex cable.

I agree this is a potentially noisy system, but by going to higher volume and lower pressure components, this could be minimized. Also the drive motors are aft; the power unit could be placed centrally for weight advantage and could provide a power source for a refrigeration compressor. Like everything else, there have been great improvements in sound insulation.

There is a power loss as there is with any transference of one form of energy to another, but I strongly consider your estimate of 20% loss in the power train to be on the high side. One of the pluses for hydraulics is the virtually unlimited cooling available for the fluids through heat exchangers.

Yes, you still have the underwater gear, but the components can be matched to minimize electrolysis and the replacement cost of these standard items is minimal.

Now to your perfect alternative, saildrive. These have also greatly improved since the early Baldwin, OMC-powered units. The alloys are much better, but you still have aluminum. You also have a large housing directly in front of the rudders, very likely to cause cavitation above 10-12 knots. Pick up a bit of loose, floating monofilament in the prop and you cut the seal out.

I have no doubt you had a problem with a hydraulic system, but you neglected to mention if the system had been checked periodically. Before you left, did you, with your surveyor’s experience, check it over for chafe or wear spots? Was it possibly installed so that the anchor chain rubbed the hose when it was used? Could a valve have been installed for use only when the anchor winch was used?

Your letter raised more questions than it answered.

I am presently converting a 40' Prout to inboard power and hydraulics are a very viable consideration. A pair of saildrives will cost over $20,000 and a 4-108 and all components is well under half that. Installation cost appears to be likewise much lower. Every propulsion system has its advantages and flaws.

I strongly suggest you pass basic engineering 101 before your next pontification.

Irwin Victor
East River Boat Yard
North, Virginia

Foul Weather Gear
Regarding your test of the new ocean technologies Gore-Tex suits and others (July 15, 1998), you make the claim that the suits are waterproof and breathable. Yet you don’t really offer any valid testing method except for one suit in a driving rain. Surely, something a bit more comprehensive was called for.

Being an avid small boater and backpacker, I’ve used Gore-Tex apparel since the early 1980’s. The fabric and methods of construction and design have come a great way in just the last few years. Gore-Tex is not, as you noted, the miracle fabric that its makers or sellers would have you believe. It is, however, giant steps above nearly any traditional coated fabric in terms of breathability and water resistance; it is relatively easy to stay dry and to keep your undergarments dry as well. Additionally, Gore-Tex functions great as wind shells and everyday rain gear. Much of the comfort of any good garment depends upon the design and the users’ understanding of the limitations of the apparel. Any serious exertion may overwhelm the ability of the inner garment, the inner liner or the Gore-Tex to move the moisture to the outside, no matter how pricey the garment. Try climbing four flights of stairs in your new $800 suit to find that out.

As an alternative, the backpacking, camping and fishing apparel manufacturers offer to the “practical sailor” an incredible variety of well-designed, well-made and durable Gore-Tex products, many of which are relative bargains compared to the serious duty offshore gear that most of us will never really need. Check with L.L. Bean, Campmor, Cabelas, REI and the like to see that you don’t have to be priced out of the market.

Brad Boyd
Old Saybrook, Connecticut

Leisure Furl Distributor
We were pleased to note the announcement that Leisure Furl was named one of the “Gear of the Year” winners. You noted that Hall Spars is the source of Leisure Furl, but you failed to point out that Forespar markets the product in the western states and provinces and Hall Spars in the east. I would appreciate you making that point to your readers.

Bill Hanna
Forespar Products Corp.
22322 Gilberto
Rancho Santa Margarita, CA 92688

I have been reading your excellent magazine for years now and have found it a valuable source of information and ideas. However, in the September 1998 issue you have missed a trick when describing how to read an aneroid barometer such as the Weems & Plath Atlantis.

The trend of the barometric pressure is more significant than the actual pressure reading. The correct method of ascertaining this depends on the hysteresis in the barometer mechanism and works as follows:

Set the adjustable needle to coincide with the current reading, and then tap the adjustment knob sharply. The indicating needle will move slightly, either up or down, indicating the trend as well as a more accurate reading of the pressure. The movement of the indicating needle is usually too slight to notice unless the adjustable needle has been set first.

With this method you get the reading and the trend right away without waiting around an hour or so.

Edmond Carley
Copiague, New York

The report on barometers had a serious omission—the most basic of all barometers, a tube of mercury. For many years I had one which I had built from a kit on my Essex 26, screwed to the mast support, where it was readily visible and well protected. No offense to Weems & Plath, but for nautical tradition this had the barograph beat all to hell.

After poor health grounded me, I removed it to my beach home, where it faithfully performed its function until a renter, despite its protected location, managed to break it.

I have never seen another such kit. If any of your readers can clue me in, I’d be most gratified.

Jack Childers
Baltimore, Maryland

I think you may do a possible disservice to your readers by dismissing the use of barographs at sea.

Providing that it is properly mounted, it can provide valuable graphic information at an informed glance. At least that has been my experience.

Wind it up once a week, change the graph paper and that’s it.

Allan Dannhauer, MD
Seattle, Washington

Where Credit Is Due...
To Bomar: “I own a two-year-old Manta catamaran. All of its hatches are by Bomar. The main entrance door is also a very large Bomar hatch. The center smoked plastic insert started popping out of the frame. I called Bomar to find out how to glue it back in. They asked how old it was and agreed to check it out and get back to me. Ten minutes later—not 10 days—the phone rang. Bomar said that my problem should not have happened and they would manufacture a replacement for me at no charge and apologized that it would take a month to get it through the manufacturing process...‘would that be okay?’ Do they deserve a pat on the back for standing behind their products even when the warranty period is clearly over? Yes!”

Ken Neil
Jupiter, Florida

To Tasco: “Five years ago, I bought a pair of Tasco 322BCU binoculars at the Miami Boat Show. They developed moisture inside the lenses. After reading a letter from another Tasco customer in PS, I took them back and was promised they would be fixed for a nominal charge. After four months I called and they traced them to a lost shipment, and promised replacement. Tasco replaced them with a new pair of Offshore 54 with Rubicon lenses. This is a far superior pair of binoculars than I had sent them. I am one satisfied customer.”

Capt. Wayne La Mura
Miami, Florida

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