Boat Repair and Maintenance featuring Marine-Tex epoxy systems

HOME | RECOMMENDED MARINE PRODUCTS | REPAIRS & MAINTENANCE | NEWS/PRESS | ARTICLES | Q & A | GLOSSARY | CONTACT | ABOUT US


Troubleshooting Articles— Boating Safety +

ONE Knowing How a Boat Handles Can Help Avoid Collisions - USCG

TWO Sudden Flooding Calls for Fast Action and Special Tools - USCG

THREE KNOW...
BEFORE YOU GO!
Children & Personal Watercraft - USCG

FOUR Small Boats —
Safety a Big Issue for Small Boats - USCG

FIVE 10 Ways to Paddle Safely USCG

SIX Which persons in your state are required to wear a PFD and under what circumstances?

SEVEN Renew Your Canoe Using Urethane Teflon Antifouling Boat Bottom Paint

EIGHT Tips for painting your boat bottom

Reasons to Keep Your Bottom Free from Fouling

Ten Better boat performance with propeller coatings

Eleven Antifouling boat paint can overcome rising fuel costs

Twelve How to sail faster, use less fuel, and reduce boat maintenance

Courtesy of the United States Coast Guard
– A Few "Boat Responsibly!" Reminders from the United States Coast Guard –
ONEKnowing How a Boat Handles Can Help Avoid Collisions

Boat Responsibly! USCG"I've been piloting boats since before I could walk!" Maybe so – but no matter how experienced you may be as a boater, it’s worth paying attention to the handling characteristics of every boat you own or operate. Every boat – even boats of the same type, from the same manufacturer – handles differently. Your own boat responds differently from day to day as a result of weather, current, temperature, load, and other factors.

The boater who ignores handling characteristics is risking his safety. Coast Guard data show that “collision with another vessel” is the number one type of recreational boating accident; "collision with a fixed object" is second.

If you’re interested in the technical factors that influence handling characteristics – things like side force, frictional wake current, and drag – a review of one of the many boat handling and seamanship publications, or the specifications supplied with your boat, will provide a wealth of useful information. But in the meantime, there are simple steps that the U.S. Coast Guard recommends that every boater – including experienced boaters –go over as a matter of routine.

Drill It In
Whether you've been operating a particular boat for three years or three minutes, it's a good idea to try some drills related to boat handling. Pick an open area on a calm day. Practice turning, stopping, and reversing course at various speeds, and pay attention to your turning radius, stopping distance, and maneuverability when the boat has more or less momentum.

Later, try the same drills in rougher water, with more wind, and with more or less weight in the boat. You may be surprised how much these variables can change the way your boat handles. At a minimum, these drills should be conducted on an annual basis, especially if you live in an area of the country where your boat is stored during the winter. Once your boat has been launched for the summer boating season, take some time to reacquaint yourself with your vessel's handling characteristics.

A Weighty Issue
Do you know how much you weigh? Not trying to ask personal questions – but as the boat owner or operator, it's important that you know the total weight of the equipment and persons you bring on board, and make sure that it’s within the limits listed on your boat’s capacity plate (if one is provided). You must take into consideration everything you’ve taken on board, such as fishing gear, a cooler, water (eight pounds per gallon), food, and fuel (six pounds per gallon). Exceeding your boat’s rated capacity is dangerous and can severely affect safe handling.

Even if you’re within the appropriate weight limit for your vessel, that weight must be properly distributed. Power trim and trim tabs are useful tools – but it’s better to carefully balance weight fore an aft, port and starboard, to avoid listing or "porpoising" – both of which make handling a vessel more difficult.

NOAA News is Good News
Finally, check the weather before you go out – and not just to find out whether or not you’ll need a sweater. Wind and waves, in particular, can drastically change a boat’s handling characteristics. Take a few minutes to listen to the National Oceanic and Atmospheric Administration (NOAA) marine forecast on your VHF radio, even if it’s currently bright and sunny. You’ll be much better off making the conscious decision not to pilot your boat in 30-mile-per-hour winds than accidentally finding out you're incapable of it. For further information on NOAA, check out http://www.noaa.gov.

Yes, you may be an experienced boater, but even if you were born with tiller in hand, it’s worth taking a little extra time to make sure you’ve mastered the handling of this boat on this day under these conditions.

* * * * * download this article * * * * *

The U.S. Coast Guard reminds all boaters to "Boat Responsibly!" For more tips on boating safety, visit
www.USCGboating.org.

Back to Top

TWOSudden Flooding Calls for Fast Action and Special Tools

A sailboat that struck a buoy in San Francisco harbor and began taking on water limps back to port under the careful watch of the U.S. Coast Guard. After sending a distress signal, the boat owner was able stay ahead of the leak using the onboard pump. U.S. Coast Guard photo by PA2 Brian N. Leshak
Consider this: you're drifting along, summer breeze caressing your face, sunlight dancing off the water, and – thunk! – a distracted angler bangs his bass boat into yours. Or - crunch! – your cabin cruiser comes hard aground on a submerged rock. Or - ptui! – a corroded thru-hull fitting pops out. Suddenly more water than you ever thought possible is pouring through a hole in your boat’s hull. What to do?

If you've thought about flooding when putting together your on-board emergency kit, and if you've trained yourself to handle this kind of crisis, then you have a good chance to make it back into port. If not, then it's an especially good thing you and your passengers chose to wear those life jackets.

The amount of time a boat operator has to respond to sudden, uncontrolled flooding depends strongly on the size of the hole and its location below the water line - the lower the hole, the greater the incoming pressure. A one-inch hole in the hull just one foot below the surface floods at a rate of about 20 gallons a minute. That same small hole six feet below the surface floods a nearly two and a half times that rate. And larger holes? Well... let's just say you need to act very fast.

Adding flood damage control to your vessel’s emergency kit needn’t be expensive. You may find most of the supplies and tools already at hand.

For recreational boats, a flood damage-control kit starts with an assortment of the following:

Plugs and patching material: wooden wedges and tapered wooden plugs in a variety of sizes to match the boat’s thru-hull fittings; an assortment of rubber sheets and gasket material; rags, waterproof putty, and other filler for stuffing in and around patches for a better seal.

Fasteners to hold the patch in place: hose clamps, nylon ties, twine, grease tape, Fiberglass tape, and duct tape.

Tools to make it all happen: screwdrivers, a hacksaw, an adjustable wrench, pipe wrench, nut driver, and a hammer. These are not just to help patch the hole but to help close watertight doors and hatches, shut down machinery that could make a flooded area hazardous, and close off drains and discharges that can siphon water into the boat if they sink below the water line. Also, since bilge pumps aren’t designed to handle the large volumes of water caused by a hole in the hull, a dewatering pump is a recommended investment.

All of these, along with other emergency kit components, need to be in a container that's clearly marked and close at hand. Attach a flashlight to the handle should an accident happen at night, and make sure everyone on board knows where the emergency kit is located.

Careful maintenance and regular inspection of pipes, gaskets, valves, and fittings can greatly reduce the chance that mechanical failure will lead to flooding. Boating education and knowledge of navigation rules and local conditions will minimize collisions, allisions (running into fixed objects, like the pier), and hard groundings. Still, there's no substitute for preparation. Vessel damage control training is widely available through the U.S. Coast Guard Auxiliary and other boating groups, and the local harbormaster or U.S. Coast Guard office can direct you to course offerings nearby. Once you are trained, hold a monthly drill to practice quick action in an emergency.

And don't forget the most important step in damage control: communication. Notify the Coast Guard and other boaters in the area if your boat is taking on water. Make sure you and all of your passengers are in life jackets. Saving your boat is important – but if flooding can't be brought under control, the priority is saving lives.
Here the sailboat crew was able to plug the holes and dewater the vessel, preventing it from sinking.

* * * * * download this article * * * * *

The U.S. Coast Guard reminds all boaters to "Boat Responsibly!" For more tips on boating safety, visit
www.USCGboating.org.

Back to Top

THREEKNOW...BEFORE YOU GO! Children & Personal Watercraft

Download this informative brochure from
USCG
United States Coast Guard Office of Boating Safety
www.uscgboating.org
NTSB
NATIONAL TRANSPORTATION SAFETY BOARD
www.ntsb.gov
NASBLA
NATIONAL ASSOCIATION OF STATE BOATING LAW ADMINISTRATORS
www.nasbla.org
NSBC
NATIONAL SAFE BOATING COUNCIL
www.safeboatingcouncil.org

Back to Top

FOURSmall Boats — Safety a Big Issue for Small Boats
Give your Boat a Quick Inspection Before Heading Out on the Water

Make sure everyone on board wears a life jacket.It doesn’t require a 40 ft. cabin cruiser to enjoy the nation’s many lakes, rivers, and coastal waterways, but those operating small boats to engage in water-related activities do need to be aware of their boat’s limitations and behave accordingly.

Statistically, more than 80 percent of all boating fatalities occur in boats less than 26 feet in length, often the result of capsizing or falls overboard. In many cases, a contributing factor is one or a combination of the Coast Guard’s Big 4: excessive speed, reckless operation, operator inattention/inexperience, and boating under the influence.

But other factors point to hazards particular to smaller craft. In small, open-constructed boats, the wave-size-to-boat ratio is much less than on a larger boat, and a small boat will fill with water more quickly if washed over by a large wave, or even a small one. Transoms and helm station areas are wide open and the boats have smaller and fewer bilge pumps, or none at all. Also, decks are not watertight, and water can enter and damage the control cables, leaving the boat stranded.

Even empty, such boats have little to no freeboard – the distance between the rail or top edge of the boat and the waterline – and even less when fully loaded with occupants, food, and gear. It's easy to overload these vessels unintentionally, and an overloaded boat is more likely to capsize, even in relatively calm waters.

So keep in mind your boat’s maximum load capacity. On most mono-hull boats up to 20 feet long, this information can be found on the capacity plate, permanently affixed to the hull by the manufacturer. It notes the maximum horsepower rating and maximum load weight at which the boat can safely operate. If a capacity plate isn’t present, one easy formula for calculating the maximum load for a mono-hull boat is to multiply the boat’s length times its width and divide by 15. As such, a 6 ft. wide, 18-foot boat can carry up to 7 people safely.

To make capsizing even less likely, be sure your load is distributed evenly to keep the boat balanced. Standing for any reason in small boats, even changing seating positions, can raise the center of gravity and make the boat less stable. The same is true for sitting on the gunwales or seat backs, or on a pedestal seat while underway. A raised center of gravity means that a wave, wake, or sudden turn can result in a person falling overboard.

For safety’s sake, complete a pre-departure checklist prior to launch to make certain your boat is in good working order and has all the necessary safety equipment on board. And, big boat or small, be sure to check the weather report and waterway conditions, bearing in mind that conditions considered safe for a 40-foot boat might be unsafe for one half that size.

Small boats are a lot of fun and important to many water-related activities. Take a moment to do a 15-minute inspection before launch, watch your load, and mind the Big 4. Make sure that all of your small boat journeys are safe ones.

Complete this Pre-Departure Checklist
To make sure your small boat is “seaworthy” and that all essentials are on board, set aside 15 minutes for a quick inspection before launch.

  • Check the operating condition of your boat: motor, steering, battery, hoses, clamps, bilge pumps, wiring, fuel tanks, lines, float switches, and lights.
  • Make sure you have a U.S. Coast Guard-approved life jacket of correct size and type for you and every passenger (and, on the water, make sure they are worn, not just stowed).
  • If your boat is greater than 16-feet in length, be sure you also have a Coast Guardapproved throwable flotation device – i.e. buoyant cushion, ring buoy, or horseshoe buoy (kayaks and canoes are exempted from this requirement).
  • Check for other safety equipment appropriate to the size of your boat and the area where it will be operating; for example, flashlight, tool kit, first-aid kit and sunscreen, paddles, oars, binoculars, anchor and anchor line, fire extinguisher, spare battery, visual distress signals, charts of the local area, and a VHF-FM marine radio.
  • Check the capacity plate (if affixed to the hull) or calculate the maximum load to make sure you don’t overload the boat with passengers and gear.

You can also download a Pre-Departure Checklist from the U.S. Coast Guard at http://uscgboating.org/safety/fedreqs/saf_prechecklist.htm

* * * * * download this article * * * * *

The U.S. Coast Guard reminds all boaters to “Boat Responsibly!” For more tips on boating safety, visit
www.USCGboating.org

Back to Top

FIVE 10 Ways to Paddle Safely USCG
SIX Which persons in your state are required to wear a PFD and under what circumstances?
SEVENRenew Your Canoe Using Urethane Teflon Antifouling Boat Bottom Paint

Turbulence eats up energy and can slow down your canoe. It has been known for a long time that a 2-inch scratch on a smooth surface can generate turbulence for 10 or 12 inches as water flows over the scratch. If you have an older canoe, its bottom is probably no longer smooth.

Fairing your canoe bottom is not that difficult and can be done in a few hours with simple hand tools and under $50 in materials. First use a 100-grit sanding sponge or palm sander with purple 3M-type paper to clean the bottom.

Then get out the glazing compound. You can find it at www.boatrepairandmaintenance.com for $3.98 a tub. You will need one or two tubs for an older canoe. Use the plastic putty knife that comes with the glazing compound right out of the tub with no mixing and fill in all your nicks on the bottom. The glazing does not need to be perfectly flat because it sands easily to flush it up with the existing canoe bottom. Allow the glaze to harden for about 1 hour and sand off with a sponge or palm sander. Then repeat until the bottom is smooth.

Next seal the canoe bottom. You want to use a great non-stick coating like that used on cookware. Cookware coatings are based on the largest molecule known, one that has a lower drag coefficient than ice. This type of coating was first developed by DuPont and marketed under the name Teflon. A good choice is Smooth Sailing Boat Bottom Urethane Teflon Paint which comes in three colors.

Use blue tape to mask off the water line. Then mix the urethane and hardener 3 parts A to 1 part B hardener and apply with a 9-inch mohair 1/4" nap roller. A good technique is to just pour a little urethane on the bottom and then wet the roller, spreading the urethane out as thin as possible. By the time you get to the end of the canoe, you probably can start over with your second coat. If you see some bubbles as you go, just roller over again to break them.

After two coats (about 400 cc of material), let it harden for 5 hours, sand off problems, and do your final coat. If drips over the mask or on the side of the canoe occur, just wipe off with thinner while the urethane is still wet. Note that you should get your final coat on within 10 hours of the first coat to assure good adhesion. If you get any orange peel or if the bottom is not as smooth as you like, get out that wax orbital buffer and some light rubbing compound to smooth down to that perfect glass finish.

Back to Top

Click images to enlarge

Original surface
Original surface

first glaze
First glaze

sanded first glaze
After sanding

first coat
First coat

second glaze
Second glaze

Final result
Final result

EIGHT Tips for painting your boat bottom

Instructions for applying boat bottom paint

1. Setting up to paint your boat bottom
You can paint your hull safely and easily when on your trailer, cradle, or blocked storage system. Support points should be touched-in just before launching. Just shift the boat, sand lightly, touch-in, and wait 10 to 30 minutes before launching. Our copper nonstick and our clear nonstick paints dry in 10 minutes or less. Our urethane nonstick paints dry in 30 minutes.

2. Pressure washing your boat bottom
The key to bottom painting is adhesion. To allow your bottom paint to adhere well, your bottom surface must be hard, clean, and have a slight texture. A once-over with a 3500 psi pressure washer or better is the first step. If the existing paint is soft, where your fingernail can dig into it, you will need to bring it down to a hard finish. Using a spiraling tip on your pressure washer that applies a round stream will give you the most pressure at the hull surface. These spiraling tips can peal off soft oblate finishes to a surface that will not scratch with your fingernail. When you get there, you can quickly sand the bottom.

3. Prepping your boat for bottom paint
Sanding your boat bottom with an 80- to 100-grit sponge or palm sander is a quick and easy way to remove remaining contaminants and wax, while leaving a microscopic texture for your new boat bottom paint to adhere to. Dry sanding works well but sometimes tends to clog the grit surface requiring changes of sanding paper or sponges. Wet sanding often keeps sanding paper or sponges open to continue their work. Use whichever method is easiest. While sanding, extra time can help smooth out gel coat repairs, burs, and scratches.

4. Repairing irregularities in your bottom
You may use glazing compound over your old paint or between new coats to fill and smooth the hull before applying your new boat bottom paint. You should lightly sand, and wipe dust free, any surface before coating. Touching in or striping newly glazed areas is recommended before the final coat is applied. This will help prevent show through, by (in effect) adding an extra coat over the repaired areas.

5. Taping your waterline or striping
Using a fresh role of blue masking tape will save a lot of time and effort. Once the hull is dry, you can pull the tape from stem to stern. Use a cock line if you wish or follow your old water line. To stripe, you can use striping tape or just pull two tapes along your hull and brush your color in from the tap to the center. Whenever you use tape, it is best to pull it off before the bottom paint dries or you may glue it to the hull. Have a little thinner available before the bottom paint dries to remove drips.

6. Mixing bottom paint
1. The clear nonstick boat bottom paint is ready to use but should be stirred. It will not yellow over time. The clear can go over any surface without changing the underlying color. Most boat waxes are water based and will wash off with time as they dissolve in water. Smooth Sailing clear nonstick can be used both below and above water to protect boat hulls in place of on going waxing.

2. The copper nonstick boat bottom paint comes with the copper component in a separate pouch. This is to prevent the copper grains from settling in the can before application. You need to add the copper powder into the clear nonstick coating and stir until fully mixed (about 1 minute) before application. The copper will stay suspended for about 24 hours but mixing occasionally is a good idea.

3. Smooth Sailing urethane nonstick coating is a two-part mix. The catalyst is mixed with the color component at a 3 to 1 ratio by volume. Once mixed, the coating should be applied within 2 hours, as it will set up in the can within 18 hours.

7. Clear and copper coating characteristics
The nonstick clear and copper have almost no odor and dry in 10 minutes or less on the hull. The boat can be placed in the water immediately so areas that had pads or rollers can be coated as the boat is moved to the water.

8. Characteristics of nonstick urethane
Smooth Sailing urethane comes in popular colors and lasts up to 11 years without recoating. While our urethane contains no copper as a deterrent to organisms, it does have an antifouling agent and a very low drag coefficient so most organisms slide off at speeds of 15 to 20 knots. Urethane does have some odor. When applying in closed spaces, a vapor mask is recommended. In open air, no mask is normally required. The product starts to dry in about 10 minutes and is hard enough for launching in about 30 minutes in warm weather. Application should be done in temperatures of 55 degrees F or higher.

9. Application of coating
The first coat should be sprayed or applied with a 9-inch mohair roller and/or brush. The second coat can go on any time after the first coat is hard, but waiting about 15 minutes for the copper and clear and about one hour for the urethanes is recommended. Avoid introducing air into the urethane to avoid bubbles. If bubbles occur some light sanding may be needed and a recoat of the bubbled area.

10. Tricks for application
Putting your mixed boat bottom paint into a squeeze bottle, such as a clean dish soap bottle or a squirt type drinking bottle, can help keep the solvents used from evaporating. The less air exposure your mixed paint has the easier it will flow over the boat bottom surface. Going just one direction during your application helps to avoid bubbles. Starting low and moving up helps limit drips. Using a threaded handle on your roller frame allows you to reach center areas without getting dripped on. Taping your brush to a long handle with duct tape helps reach spots that your trailer or cradle tends to keep you from.

11. If you want to strip off your old finish
Often just pressure washing with the full force of at least a 3500 psi washer with a spiral tip that can apply a round stream will remove some boat bottom paints and contaminants. If you wish to remove the entire finish, you may sand to the starting finish material. You can often chemically remove your bottom paint by applying a methylene chloride type of paint stripper. (Durall makes a good one.) Chemical stripping requires plenty of ventilation, and a VOC vapor mask should be used. Often, using a 4-inch, long-handled scraper as you do your cleaning prep or paint stripping can remove all the previous finish that is about to come off the hull. Finishing with a degreaser and pressure washer with a spiral tip should complete the paint removal. (Durall also makes a good degreaser.)

Back to Top

Reasons to Keep Your Boat Bottom Free from Fouling

Safety
Heavy fouling growth reduces responsiveness of the craft. The added weight of the fouling can make the boat sit lower in the water than intended. This can have obvious implications in heavy weather conditions.

Protection
Prolonged growth of certain types of fouling can damage the substrate of the hull. For example, the natural glues that organisms use to attach to a hull, can damage wood and Fiberglass. Fouling can also clog water intakes and cause damage to engines.

Speed and Efficiency
Fouling causes drag. As drag is increased, fuel consumption increases and speed is reduced even to the point where a planing hull may not be able to get on plane. For racing boats, this can be the difference between winning and losing a race.

Smooth Sailing Antifouling coating is not meant to be a cosmetic or decorative coating. Smooth Sailing coatings rely first on the large polytetrafluoroethylene (PTFE) molecule which produces a drag coefficient smoother than ice. Smooth Sailing Antifouling also uses copper. Copper has been protecting boat bottoms from growths since the 1700s, when Britain's Fast Ships (like the Cutty Sark), raced from the Orient to England with a cargo of fresh tea. All antifouling paints change when they are immersed. The true color will establish itself after the boat has been launched. Along the waterline you will often note that the antifouling coating looks dirty or faded and can often turn color from copper to a dark gray and ultimately to a green tone. This is due to the reaction of the paint with oxygen forming green copper oxide. Because color change will occur over time, you should try to keep the Smooth Sailing Antifouling coating as close to the true waterline as possible.

How often should a boat bottom be coated?
Smooth Sailing coatings will retain their antifouling properties as long as the coating is on the hull. Sanding between coats will add longevity. By sanding the bottom in the spring you will get more coats to adhere and forestall the day when too many coats means that you must remove all the antifouling coatings from the surface and start over. Smooth Sailing coatings must always be sanded even if they have just been power washed.

Because Smooth Sailing Standard and Smooth Sailing Antifouling bottom coatings wear away with use, there is no buildup of coatings that will eventually have to be removed from the surface. The minimal buildup reduces the maintenance and preparation needed when it is time to apply more antifouling. In contrast, Smooth Sailing Urethane lasts up to 12 years and is so hard that it does not wear away. Because of its long expected life, coating buildup is usually not an issue since five or six coatings can be applied before any thickness build up is a concern.

A disadvantage to hard antifouling paint is that frequent applications result in the buildup of residual paint film. This occurs when the surface is not properly sanded prior to the application of new coats of antifouling paint. When hard paints are hauled and stored for the winter season, the paint film, as well as the biocide, will oxidize, making it more difficult to release biocide out of the film. For this reason, they must be sanded and re-coated with fresh antifouling before re-launching.

growth on your boat bottom can increase its drag by as much as 10%Smooth Sailing coatings use PTFE, which is the same chemical used in Teflon®. Most people associate Teflon® with nonstick household products or with the space program, but the properties that make it perfect for those applications also make it an ideal ingredient in antifouling coatings. PTFE creates the lowest coefficient of drag in any coating available. The lower the friction, the less energy is required to move the boat through the water. For powerboats this means greater RPM's, increased speed, and fuel savings. For sailboats, greater speeds are achieved with less wind. Because PTFE melts at 400 degrees or more, it will not flow into gel coat pores when wet sanded, so new coats can be applied at any time.

Antifouling performance factors
The level of copper is not the only determining factor of how well an antifouling paint will perform. The resin-binder system (the material that holds the paint together), has its own antifouling agents and is equally important. The amount of copper affects the life of an antifouling coating but the sophistication of the resin-binder system to hold and release copper is far more important to the effectiveness of the antifouling effect. Smooth Sailing Antifouling will release biocide at a nearly constant rate throughout its life. For this reason, the highly efficient Smooth Sailing Antifouling is less dependent on large amounts of copper to deliver the best possible performance.

Fluorourethane
Fluorourethane was originated by the U.S. Naval Research Laboratories (NRL) in the early 1970s. It was a combination of a fluorocarbon (Teflon) molecule with a urethane molecule. The material was unique in that it provided a surface with approximately the same coefficient of friction as the Teflon, it was hydrophobic, UV resistant, and at the same time, provided an abrasion resistance four times that of Teflon. The fluorourethane was originally tested on several ship hulls for the U.S. Navy. One boat tested was a harbor tugboat in Chesapeake Bay. The coating lasted 11.5 years compared to a conventional hull coating which lasted only 18-24 months. Of major interest was the fact that no rust or corrosion occurred under the coating. And biofouling, such as barnacles, could be removed with a high-pressure water jet instead of chipping or shot blasting.

Back to Top

Ten Better boat performance with propeller coatings

Better boat performance with propeller coatings
Harvey M. Chichester, Durall Manufacturing
MINNEAPOLIS, MN, December 27, 2008—

Turbulence eats up energy and can slow your boat down. It has been known for a long time that a 2-in. scratch on a smooth surface can generate turbulence for 10 or 12 inches as water flows over the scratch. Just think how much water passes over a boat's propeller compared to the amount of water sliding past the hull.

In fact, a study* released in 2006 at the International Conference on Advanced Marine Materials & Coatings in London notes that, "When the reduction in ship performance is associated with the condition of the ship hull, the effect of the propeller surface condition is often overlooked. Nevertheless, the effect can be significant." The report concludes that, "The results of the calculations show that significant losses in propulsive efficiency resulting from blade roughening can be regained by cleaning and polishing of the blades. Alternatively, the efficiency losses could be avoided, perhaps indefinitely, by the application of a paint system that gives a surface finish equivalent to that of a new or well polished propeller. A foul release coating is such a paint system."

Now boat owners can do their own tests thanks to a new urethane Teflon-type coating from Durall's Smooth Sailing™ line of boat paints.

Non-stick cookware uses the largest molecule known, a molecule that has a lower drag coefficient than ice. This type of coating was first developed by DuPont and marketed under the name Teflon. Now Durall has made available a clear brush-on coating, using the same molecule, for use on your prop. The coating will never yellow and can be built up to smooth out all those little scratches, pits, and imperfections that can plague your propeller.

Aerospace engineers are currently testing this new coating on boat props in order to verify that reducing drag on the propellers will allow more energy to be transmitted to forward speed and less burned up in friction.

The question for boat owners is why wait for testing data when for under $4 you can quickly apply a non-stick coating on your prop? A new urethane Teflon-type coating with a zinc chromate primer is now available in a prop coating size at www.boatrepairandmaintenance.com. Judge for yourself if that prop is turning better. After all, it's your tests that really matter.

For more information on these types of coatings, see our Durall® products page.

* Effect of a Foul Release Coating on Propeller Noise 2006, by R. J. Mutton, M. Atlar, M. Downie, and C. D. Anderson. International Conference on Advanced Marine Materials & Coatings, London, UK, February 22-23, 2006. A copy of the full report on the propeller study is available, click here to download propeller_study.pdf.

Back to Top

Eleven Antifouling boat paint can overcome rising fuel costs

Antifouling boat paint can overcome rising fuel costs
Harvey M. Chichester, Durall Manufacturing

Boats with fouled bottoms can use as much as 10% more fuel. This means that now, more than ever, you need to employ the technology that racing sailboats have been using for years: antifouling, non-stick, copper/Teflon boat bottom paint. These easy-to-apply bottom paints, or bottom coatings, can save every boat owner money.

How non-stick, racing-type boat bottom paints work:
1. To produce smooth hulls, racing-type boat bottom paints use the same molecule contained in non-stick cookware, the largest molecule known, with a drag coefficient smoother than ice.

2. Copper is often embedded in these fast Teflon-type coatings, causing barnacles, zebra mussels, algae, and other water growths to reject them and seldom attach themselves to your bottom.

3. These coatings slough off like a bar of soap, taking growth away with them as water passes over the hull, keeping the boat bottoms smooth.

A few negative aspects to using non-stick, racing-boat bottom coatings:
1. The boat bottom requires recoating every few years as the finish wears away.

2. Sanding is needed every few years so the next coating will adhere well.

3. The boat bottom color will darken as the copper oxidizes, turning a dark brown/gray.

Cost may not be a major factor. A 20- to 30-ft. boat can be coated for under $100 in materials. Not a bad price to pay for a 10% savings in fuel costs.Protecting your boat bottom from growths also helps maintain the value of your boat. In years gone by, ship hulls allowed for rusting to wear away 2/3 of the steel over the life of the ship. But today, with urethane Teflon-type bottom coatings, ships can go 11 or 12 years without recoating or loss of steel thickness. In the 70s, the U.S. Navy tested these non-stick coatings on five ships and were impressed that residual growths that had not come off after speeds of 10 to 15 knots were reached could be removed with simple pressure washing. This eliminated grinding and the associated hull wear.

For more information on these types of coatings, visit www.boatrepairandmaintenance.com. Charts are provided which will allow you to identify the amount of material required for your boat.

Back to Top

Twelve How to sail faster, use less fuel, and reduce boat maintenance

How to sail faster, use less fuel, and reduce boat maintenance
Harvey M. Chichester, Durall Manufacturing

Growth on the bottom of a boat can reduce its efficiency by as much as 10%. Once fouling has established a hold on a boat hull it will rapidly spread or "colonize" the surface. Prevention is therefore better than the cure of having to remove the fouling by scraping.

Fouling can pose a safety risk. Heavy fouling growth reduces responsiveness of the craft. The added weight of the fouling can make the boat sit lower in the water than intended. This can have obvious implications in heavy weather conditions.Furthermore, fouling can damage the boat. Prolonged growth of certain types of fouling can damage the substrate of the hull. For example, the natural glues which organisms use to attach to the hull can damage wood and fiberglass. Fouling can also clog water intakes and cause damage to the engines.

Fouling also causes drag. As drag is increased, fuel consumption increases and speed is reduced even to the point where a planing hull may not be able to get on plane. For racing boats, this can be the difference between winning and losing a race.

The best preventive measure is to coat the hull with a specially manufactured boat bottom paint designed to inhibit growth and barnacle attachment, to provide a reduction in friction with the water, and to protect the hull for a long time. The benefits of coating the bottom are less fuel use, faster sailing or motoring, the ability to clean the hull by pressure washing rather than scraping, and less long term maintenance with better resale value.

Antifouling boat bottom coatings are not meant to be cosmetic or decorative. The best boat bottom coatings incorporate the large polytetrafluoroethylene (PTFE) molecule which produces a drag coefficient smoother than ice. One implementation, fluorourethane was originated by the U.S. Naval Research Laboratories (NRL) in the early 1970s. It was a combination of a fluorocarbon (Teflon™) molecule with a urethane molecule. The material was unique in that it provided a surface with approximately the same coefficient of friction as the Teflon®, was hydrophobic, UV resistant, and at the same time provided an abrasion resistance four times that of Teflon. The fluorourethane was originally tested on several ship hulls for the U.S. Navy. One boat tested was a harbor tugboat in Chesapeake Bay. The coating lasted 11-1/2 years compared to a conventional hull coating which lasted only 18-24 months. Of major interest was the fact that no rust or corrosion occurred under the coating.

The best coatings also employ copper. Copper has been protecting boat bottoms from growth since the 1700s when Britain's Fast Ships, like the Cutty Sark, raced from the Orient to England with cargoes of fresh tea. While tin and other biocides have been used on boat bottoms over the years, the proven standard still relates to the level of copper used. Yet copper is not the only determining factor of how well an antifouling paint will perform. The resin-binder system, the material that holds the paint together, is equally important. In addition to holding the paint together, the resin-binder system determines how fast the copper and other biocides are released. The resin-binder system should be carefully tailored for the amount and type of copper used to obtain maximum efficiency. The amount of copper affects the life of an antifouling coating but the sophistication of the resin-binder system to hold and release copper is far more important to the effectiveness of the antifouling effect. The best antifouling boat coatings release biocide at a nearly constant rate throughout their lives. If the resin-binder is correct, lesser amounts of the highly efficient copper biocide are needed to deliver the best possible performance.

Antifouling coatings will retain their antifouling properties as long as the coating is on the hull. Sanding between coats will add to the longevity of the bottom jobs. By sanding the bottom you can get more coats to adhere and forestall the day when too many coats means that you must remove all the antifouling coatings from the surface and start over. The boat bottom should always be sanded before an additional coat even if it has just been power washed.

Back to Top

Knowing How a Boat Handles Can Help Avoid Collisions - USCG | Sudden Flooding Calls for Fast Action and Special Tools - USCG
KNOW...BEFORE YOU GO! Children & Personal Watercraft - USCG | Small Boats — Safety a Big Issue for Small Boats - USCG
10 Ways to Paddle Safely USCG | Which persons in your state are required to wear a PFD and under what circumstances?
Renew Your Canoe Using Urethane Teflon Antifouling Boat Bottom Paint | Tips for painting your boat bottom
Reasons to Keep Your Bottom Free from Fouling | Better boat performance with propeller coatings
Antifouling boat paint can overcome rising fuel costs | How to sail faster, use less fuel, and reduce boat maintenance

Marine-Tex On-Line Store is Open

Marine Tex® Products: See All Marine Tex® Products | Marine Tex® FAQ | Marine Tex® How To... GET ANSWERS

Smooth Sailing Boat Bottom Paints - Durall® Products: See All Durall® Products



About Boat Maintenance and Repair website Home
Marine Products Marine Products...find the best product for your money
Maintenance & Repairs Boat Repairs & Maintenance... from simple to major projects
Troubleshooting News/Press
Boating Articles Articles...find articles on boats, boat repair, boating safety...
Questions & Answers Questions & Answers...to happy boating
Contact Us Contact Us...we're happy to share our thoughts with you and would love to share your ideas
Boat

Poster Courtesy of the United States Coast Guard

Vessel Safety Check - US Coast Guard Auxiliary

FIVE
10 Ways to Paddle Safely

10 Ways to Paddle Safely

one. ALWAYS Wear Your Life Jacket
Wear a properly fitting U.S. Coast Guard-approved life jacket at all times on the water.

two. Don’t drink while paddling
Avoid alcohol, which impairs the coordination and balance you need to control a canoe, kayak, or raft.

three. Stay Low
Learn how to enter and exit your boat safely and stay low in your boat when possible. Most paddlesport-related drownings are the result of capsizing.

four. Keep Your Balance
Don’t overload your boat. Distribute passengers, secure gear evenly and low, and leave your dog on land.

five. Practice the Wet Exit
Learn how to get out of, hang on to, right, and re-enter your capsized boat.

six. Don’t Get Left in the Cold
Dress for the weather conditions and be prepared for coldwater immersion. Hypothermia is a danger any time of year.

seven. Plan Ahead
Know the water you're paddling, plan your day of paddling, and file a "float plan" so that someone knows where to find you and when you plan to return.

eight. Never Paddle Alone
Companions can come to your aid if you get in trouble. New paddlers should paddle with someone more experienced— it's a great way to learn and remain safe if there's a mishap.

nine. Be in Command
Know how to move your boat forward, back, and sideways, and how to stop using paddle strokes. Watch ahead for hazards like undercut rocks, bridge pilings, large branches and trees, big drop-offs, or other boats.

ten. Learn about Your boat
Consider taking a canoe or kayak safety class. Call 1-800-929-5162 or visit www.acanet.org to learn about classes offered by the American Canoe Association.
Back to Top

How to choose the right Life Jacket. A handy guide from your United States Coast Guard

Marine-Tex®, FlexSet™, Gluvit™ and Te-Ka™ are registered trademarks of ITW Polymer Technologies, Montgomeryville, PA. Dural® and Smooth Sailing™ are registered trademarks of Durall Manufacturing Inc. Minneapolis, MN.
Trademarks and Registered Trademarks are the property of their respective owners.
©2012 Boat Repair and Maintenance, a division of Como Consortium Ltd. • Golden Valley, MN