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philfriedmanHullAntifouling coatings come in a variety of types and costs, but...09-20124.00
...choosing the right one for your application, doesn’t have to be stressful, if you do a bit of homework.

An aging “dock rat” once told me that cheap latex house paint works just as well as expensive marine antifouling paint on your boat’s bottom: You apply the latex and a month or so later it is completely fouled with algae, grass and barnacles — exactly like expensive marine antifouling.

The quip is, of course, ridiculous. However, it does spotlight an important truth. Unless you choose a marine antifouling paint carefully and assure that it is applied correctly, you might just as well save yourself a stack of cash by using ordinary house paint.

Manufacturing a yacht bottom coating that combats marine fouling and is at the same time practical to apply, reasonably durable, and not prohibitively expensive, is a highly complex business. Paint and chemical companies such as Interlux, Pettit, and Z-Spar, have devoted very significant research and development budgets to the problem, with the result that there is today a wide variety of antifouling bottom coatings from which to choose. Unfortunately, as the number of available options has grown, so has consumer uncertainty and anxiety levels. Indeed, many boaters and yachtsmen now face the marine paint counter with trembling indecision, while horrific visions of creeping marine crud dance in their heads.

Whoa! Relax. Whether you have a Hatteras motor yacht, a Grand Banks trawler, or Bertram convertible sport fishing boat, you can ease your bottom paint anxieties by taking a look at what antifouling coatings are all about, how they’re formulated, how they work (and fail to work), why they cost as much as they do, and how to choose one best suited to your needs.

Yacht antifouling coatings are specialized formulations whose primary function is to
retard or prevent the growth of marine animals and plants on a vessel's underwater
surfaces. These coatings accomplish this by poisoning the organisms involved and/or providing an environment that is otherwise unfavorable for the attachment and growth of said heinous marine animals and plants. The constituents of all paints, including
antifouling paints, divide into three major categories: 1) a medium or binder, 2) pigment, and 3) solvent.

The medium (or “binder”) creates the basic coating film. Subsequent to application, it converts by chemical reaction from liquid form to a solid film. Pigments are suspended in the medium, and add specialized qualities, such as abrasion resistance or antifouling
properties, to the coating film. Solvents provide viscosity (flow) control to the mixture, and prevent the liquid medium from converting prematurely to a solid film.

In an antifouling paint, water-soluble toxic pigments (referred to in the industry as "toxicants") are held in a medium or binder that enables them to be released on a controlled basis into the water immediately surrounding your boat or yacht’s underwater hull surface. It is this toxic, waterborne layer that discourages the growth of fouling organisms on the hull and underwater gear.

Nowadays, antifouling paints divide into two broad categories: 1) hard paints, and 2) ablative coatings. Ablative coatings break down further into a) soft sloughing paints, 3) b) controlled-solubility copolymers and controlled-depletion polymers, and c) self-polishing copolymers.

1. Hard antifouling paints are filled with biocides as part of the pigment, which leach out of the coating when it is immersed in water. These antifouling coatings begin life with a strong punch, but continually lose strength as the biocides are leached out of the paint film, until the level of biocide release becomes so low as to make the antifouling coating useless. Because the paint film of hard paints remains pretty much intact even after its contained biocides are depleted, repeated re-coatings, year after year, result eventually in an overly thick antifouling paint coating that tends to crack and peel and, in general, become a nuisance.

2. Ablative antifouling coatings are more efficient than hard coatings at delivering biocide to the water interface layer around a yacht’s submerged hull. Ablative paint films literally wear away (erode) as water flow passes over the paint film, There are, however, several different ways in which an ablative coating can wear away.

a) Soft sloughing antifouling paints are formulated with a natural rosin-based medium, and are also filled with biocides that leach out of the coating over time in use. The soft sloughing paints are the least expensive in terms of initial materials costs, but they are also the least durable, and tend to lose their effectiveness in a relatively short period of time. These soft paints do, however, have the advantage that, by the time their antifouling effectiveness has been expended, the paint film has mostly sloughed away,. Consequently, with these paints, there is little film build up over multiple recoatings. A disadvantage of these paints is that they generally must be launched within 48 to 72 hours of being applied, or they may lose their antifouling capabilities. As well, it is not generally advisable to allow these kinds of antifouling paints to dry out for extended periods of time during a haul outs for maintenance or repair work.

b) Controlled-solubility copolymers and controlled-depletion polymers employ a medium that is partially water-soluble. This means that the paint film literally dissolves, albeit slowly, as water passes over it. This action continually exposes new layers of biocide to the water, as the biocide at the paint film surface becomes depleted. As a result, these antifouling coatings are very effective in discouraging growth, since the strength of their biocide release does not wane significantly until the sum total of contained biocides is effectively depleted.. These paints also display the advantage of automatically reducing their residual paint film thickness in use, which avoids the insidious buildup of depleted coatings over time.

c) Self-polishing copolymer antifouling coatings contain an acrylic copolymer that reacts chemically with seawater at the exposed surface of the paint film. As with other ablative coatings, this reaction results in the constant exposure of a fresh paint layer, with full-strength contained biocides, during the entire working life of the coating. However — and this is a key point — because the ablation is the result of a chemical reaction, and not the result of water passing over the paint film surface, the biocide exposure rate is constant, whether or not the yacht moves slowly or fast, or remains static at dock.

The softer, less durable antifouling paints are generally less expensive in terms of materials first cost. The cost of haul, launch, and application, remain pretty much constant for all types of antifouling coatings. Therefore, the long-term cost of using a cheaper, soft antifouling paint may not work out to be that much less over the long run. If your boat or yacht rarely moves, and if she stays in the water continually between bottom paintings, then some cost saving may be realized with the less expensive soft antifouling paints. But if you run your boat a lot, and especially if at higher speeds, you will almost certainly find that one of the controlled solubility, controlled depletion, or self-polishing copolymer products will suit your needs better and more cost-effectively.

A final tip about brands and formulations. The efficacy of any given antifouling coating depends on the ambient water conditions that the yacht finds herself in most of the time. So do not blindly accept the recommendation of your friendly boatyard manager, for he or she may not take into account your specific needs, and may just want to sell you whatever antifouling happens to be readily at hand in the stockroom. Instead, find out what is working best for your dock neighbors at your yacht club, marina, or canal. Then, keeping in mind how antifouling coatings work, and how specifically you use your boat or yacht, decide on the best choice for your particular circumstances.

— Phil Friedman, New Build and Refit Consultant, Dwight Tracy & Friends Yacht Sales (

Captain JohnEngine and drivetrainResolving engine problems10-20113.67
When you first start up your sailboat diesel engine, look over the stern. Do you have a strong, clear flow of exhaust water? Do you see smoke coming out of the exhaust tube?Other than an initial puff or two, your engine should send out clean exhaust without any smoke.Colors point to problems like overloads, internal oil leaks, or contaminated fuel.Follow this summary to identify problem areas and take the suggested actions to resolve the problem as soon as possible...

Black Smoke - Causes and Cures

What you see are unburned carbon particles blowing out of the exhaust that creates a black cloud. Older engines may belch a belly-full or two, but no more! Read over these causes and cures...

* Clogged air filter
Remove the filter and replace. If cruising in an area where air filters are unavailable, tamp the filter on a hard surface to remove as much dirt and dust as possible.

* Plugged exhaust hose
Disconnect the hose from the exhaust and look inside the exhaust pipe opening. If it's clogged with carbon, this could indicate damaged internal marine diesel parts. Have your engine serviced asap.

* Wrapped line or Fouled bottom
Stop the boat, anchor, and remove the line. Clean the sailboat bottom. Both of these cause your diesel engine to work overtime.

* Over-sized boat propeller
Match the propeller to your engine under normal operating conditions. Avoid the temptation to fit the biggest propeller possible. Heavy passenger and sailing gear loads make your engine work harder than it should.

Blue Smoke - Causes and Cures

Oil that has leaked into the combustion chamber will burn to produce a bluish smoke that belches from the exhaust. It's o.k. to see a puff or two when you fire her up, but more than this points to serious problems. Read over these causes and cures...

* Running engine at low RPM
Idle running prevents pistons and rings from expanding enough. This allows oil to leak into the combustion chamber. Run your engine at full RPM as often as possible to prevent this problem. Persistent blue smoke means your engine needs a professional overhaul.

* Crankcase overfill
Take care not to fill your engine oil past the high mark on the dipstick. Excess oil could leak into the combustion chamber.

White Smoke - Causes and Cures

Think white-water. White smoke indicates vaporized water blowing out the exhaust tube. And it points to problems in the fuel supply. Read over these causes and cures...

* Dirty fuel
When cruising in foreign ports, you may find that you need to strain fuel before it enters your fuel tank. Use a manual screened fuel filter funnel to remove sediments. These funnels are slow but highly effective. Take care with high pressure fuel hoses. Back off on the fuel-nozzle trigger to prevent spills.

* Water in the fuel
Check the fuel filter or filters for water and drain it before you start the engine. Keep your fuel tank topped off to 90% full. Replace the deck fuel-fill cap gasket every year and tighten down the cap. All of these measures will help prevent water penetration.

* Misfire on startup
If the engine misfires, but starts--this signals a compression problem. Often, an overhaul will be needed to resolve the problem. Sporadic misfiring signals dirty fuel or water in the fuel. Change out fuel filters. Drain the fuel tank, clean it, and refill with fresh fuel.

Add a good quality biocide to your fuel tank once a month. This cuts down on algae and other micro-organisms taking up residence inside your fuel tank. Keep your tank filled to 90% to discourage growth.

AlexSafetyAIS and RTE08-20123.50
I have been planning to install AIS and an RTE on my boat and have now completed this project. Both of these items are recommended for offshore racing (ISAF) and cruising and may soon also be mandated. We have included both of these in the YACHTONUS recommended equipment list for cruising which you can find in the compare menu.

So which items to buy and how to install?

Searching for the best products was fun - the first choices to make include whether to go for an AIS transceiver or just the receiver and whether to go for single X band or dual XS band for the RTE.

Given my intentions to cruise the North Sea and Atlantic, and to equip the boat to the ISAF recommended level for offshore racing, I opted for a Class B AIS transceiver (transmits and receives) and the dual band RTE (for X and S band radar response). This gives an ideal level of visibility for a cruising yacht at an acceptable cost and electricity usage.

I have opted for the new Digital Yacht AIS 2000 and the Echomax Active XS dual band RTE. There are many equivalent products on offer and you may well chose alternatives with similar functionality.

The first problem I had was locating the devices on board. I did not want a splitter on the primary mast head marifone cable and also wanted to have a fallback in case of being dismasted. I therefore opted to install a T pole at the stern. I wanted a light model and have had this pole specially built - if anyone would like, I can have a variant built with 4 1" mounts pre-set on the T bar instead of the Glomex mounts - that will look better!

The AIS requires a dedicated Antenne and GPS requiring two 1" mounting points on the T pole - each cable is around 10m long. The Active XS mounts on a single 1" mount and has a very long cable of around 20m. When I set up the T pole and pulled the cables through, I could bring the RTE to the switching panel, but the AIS cables only reached the rear cabin!

I extended the 10m cables by adding on new 10m cable extensions but found the wiring of the connectors on the new cables to be faulty - you need to test whether the cables have good quality to ensure they work! The Digital Yacht configuration program on the PC will reveal the "VSWR", which was 35:1 for the faulty cable and 1.5:1 for the correct cable. Try to minimise the length of cable and number of connectors where possible - these are sources of degradation in signal quality.

Once set up the combination of RTE and AIS is ideal. As a yacht you are simply not visible at sea without these devices! With both, I could see larger ships changing course to give way to give way to me and one guard vessel for an ocean survey ship called me by name to request clearance for 4 mile long cables the ship was towing.

The AIS transmits at 2W and mounted on the stern pole, will be receivable by other ships at 5 nautical miles - usually enough for them to take action. I could see other Class A AIS ships up to 12 miles away as they transmit at a higher power level on higher masts.

I would highly recommend both AIS and RTE for any yacht putting out to sea. The pictures show a situation where numerous ships were present in poor visibility - the two ships in the distance (look carefully they are there) changed course to give way to me and I could track them on AIS and on radar.

In very many cases, a well planned and executed modification to a yacht’s paint scheme can yield aesthetic improvements way out of proportion to the cost.

Consider the case of a 90-foot Bahamas Cruiser style yacht that I was asked to improve. She is a luxurious, spacious, and ultimately very practical vessel that exhibits an admittedly somewhat boxy, some might say ferry-like look. But the addition of three well-planned paint stripes transforms her into an exceedingly handsome yacht, by anyone’s standards. A broad “window” stripe brings a longitudinal unity to her overall appearance and reduces the apparent height of her superstructure. A mid-topside hull stripe gives her a longer, leaner look. And an eyebrow stripe produces a pleasingly crisp transition from house to flybridge structure. All at a cost far less than you might ever expect.

A alternative to paint, when it comes to such striping, is bonded vinyl film. Some of the new weather-resistant films now prevalent in the sign and auto "wrapping" industries,can be used to apply stripes to your yacht, with very little fuss or muss. You just need a steady hand and a good eye...and of course, you need to plan and layout your stripes before you beging to apply them.

Phil Friedman, New Build and Refit Consultant, Dwight Tracy & Friends Yacht Sales

philfriedmanEngine and drivetrainRunning your engine
at less than max rpm may not increase its longevity or save fuel.
So there I am, shooting my mouth off about diesel engine maintenance and longevity, and this guy on the Hatteras motor yacht next to me says, "Hey, what's the big deal? All you're saying is the harder you run an engine, the faster it wears out and the slower you run it the longer it lasts. Any bozo can see that.”
Naturally, I was wounded by the remark, but I managed to reply calmly, "No, that's not what I'm saying." And the exchange initiated a discussion that saw the sun set and my waiting supper turn to tepid mush, and me realizing I’ll never learn to keep my big mouth shut.
Anyway, be that as it may, there are several really important points to be made about the issue. Regular oil changes, proper fuel filtering, and the like notwithstanding, the most effective way to derive maximum longevity from your boat’s engine is to operate it within its specified horsepower range. Contrary to common belief, this cannot be guaranteed by simply by operating the engine below its maximum rated rpm, for example, by running an engine with a maximum rated 2300 rpm at 1800 rpm. The fact is you can overload an engine, and consequently increase its rate of wear, at just about any rpm. Here's why.

An engine develops power in response to load. At any time, your engine may be producing more or less horsepower than its rating specifies. The more horsepower the engine produces, the more internal heat and stress it produces. Since these factors contribute to wear, increased horsepower (or, more accurately for our purposes, increased torque) means shorter engine life. Therefore, the key to maximizing engine life is to keep torque and horsepower production at or below the maximum levels specified on your engine's rating curve. How do you do that, you ask, since you can't measure horsepower without a dynamometer (a bench- or floor-mounted resistance brake)? Or can you?
Horsepower is a measure of work accomplished, and is the product of torque and engine rpm. Other factors held constant, torque is produced by combustive force in an engine’s cylinders acting through its pistons, connecting rods and attached crankshaft. Combustive force is determined by the quantity of fuel burned, which in tum depends on the throttle setting. For instance, if you need full throttle to reach 1800 rpm on an engine with a rated maximum rpm of 2100, that engine is likely developing more horsepower than it is rated to produce at that point on its rpm curve. So, that engine is likely wearing out as a faster rate than the engine manufacturer anticipates or judges acceptable. You can draw the same conclusion if your engine fails in operation to be able to achieve its maximum rated rpm or takes an excessively long time to do so.

A good way to keep tabs on torque and horsepower production is to monitor fuel consumption. By comparing actual fuel burn with that charted on an engine's rating curve, you can judge whether the engine is being overloaded or not. If your engines are expensive units, this may be a good reason to install fuel flow metering, if you don’t already have electronic monitoring that provides the needed information. Moreover, understanding what percentage of your engines capacity for power production you are actually using gives you a good indication of a number of other key items, for example, how well your reduction gears and props match the engine's rated power curve and, therefore, whether you can expect any improvement with adjustment to such factors.

Perhaps even more importantly, since fuel bum varies with load, total fuel consumption is a better indicator of accumulated engine wear than engine hours. As a senior applications engineer at Caterpillar once told me, "If you run a 10,000-hour engine only under light loads, independent of rpm, it will last a heck of a lot longer than 10,000 hours before needing an overhaul." Given that fuel burn is closely linked to torque and horsepower production, and therefore heat and stress, he pointed out further that, "The most practical field indicator for determining accumulated engine wear is the total, accumulated amount of fuel burned."
Indeed, today, most major marine engine manufacturers including Caterpillar, have programs for scheduled maintenance that are based on accumulated fuel consumption, as the preferred alternative to engine hours. The principle is straightforward. The higher the engine loading, the more fuel you put through your engine in a given period of running time (engine hours), and therefore the more rapidly the engine will wear. The converse is that a generally lightly loaded engine will wear less during the same period of running time. All of which is a very strong argument for basing maintenance intervals on accumulated fuel burn, rather than engine hours.

An engine's fuel curve depends on its rating, which relates to specific load and duty conditions. The precise nomenclature chosen varies somewhat from manufacturer to manufacturer, but some common rating designations are: 1) continuous, 2) intermittent, and 3) maximum intermittent duty. An engine rated for continuous duty can be operated at its maximum rating for its entire designed life, i.e., TBO or time between major overhauls. Continuous duty horsepower ratings are generally applied to commercial applications and are typically lower than other ratings. A rating for intermittent duty allows for more horsepower to be drawn out of a given engine, but not on a continuous basis. Engines rated for maximum intermittent duty typically offer the highest horsepower for a given engine, but do so only for very brief intervals, in between which they must be operated at intermittent or continuous duty levels in order to achieve their rated TBO.
Maximum intermittent duty rated diesel engines often have the shortest projected TBO, followed by intermittent duty rated engines, and then continuous duty rated engines, for which will be projected the highest TBOs. When some manufacturers rate for intermittent or maximum duty, they limit engine hours at higher load levels to ensure their engines last the projected TBO. Others, however, say that their intermittent or maximum duty engines will last for the same number of hours as one rated for continuous duty, provided the engine's load history conforms to the specifications for the rating. Check with the manufacturer of your engines or prospective engines to see which policy applies in your case. And be sure to ask about the manufacturer’s preferred method for determining regular maintenance intervals.

— Phil Friedman, New Build and Refit Consultant, Dwight Tracy & Friends Yacht Sales,

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