18 JUNE 2017 • FOGHORN FOGHORNFOCUS: OPERATIONS Ad 1 | 1/4p | 3.375” x 4.875” www.propspeed.com PROPSPEED® is effective on: Propellers | Rudders | Shafts | Struts | Trim tabs | IPS drives | Thrusters Keel coolers | Underwater lights (clear coat) | Any underwater metal surface PROPSPEED® can be used on boats of all types & sizes Both recreational and commercial, from sport-fishers, cruisers, sailboats and superyachts to work boats like ferries, trawlers, tugboats, research ships and patrol boats. Save on your boat’s running costs Having clean props and running gear lowers maintenance costs, reduces corrosion and decreases fuel burn. “We now have five Gladding-Hearn boats. They are the 747 of our water-taxi fleet. They’re dependable, well built, and our customers really like them. The yard is also easy to work with, responsive and stands behind their product.” Tom Fox, Chief Executive Officer New York Water Taxi Gladding-Hearn all-aluminum construction, Incat-Crowther Designs, LOA 72', beam 27', 149 passengers, speed 26 knots with 12 metric tonnes of deadweight. It takes experience to integrate customer detailing and guaranteed speeds, backed by dependable customer service. All at a price you can afford. If you’re looking to build a new boat or upgrade an old one, we can offer com- plete design and construction, from security patrol boats to high-speed ferries. To learn more call Peter Duclos at 508 676-8596 or visit: www.gladding-hearn.com. The 747 of our fleet Best Practices for Eliminating Corrosion Concerns By Josh Stickles, Metal Shark W ith over 30 years in the b u s i n e s s o f b u i l d i n g aluminum boats and nearly 1,000 aluminum vessels now in service, Metal Shark has amassed formidable experience when it comes to corrosion mitigation. We have developed a list of best practices aimed at eliminating corrosion concerns. This list of practices continues to evolve as new materials and technologies emerge. Many of the practices we incor- porate into our new builds can also be used by vessel owners to thwart potential corrosion issues on their own boats. In simple terms, the two primary causes of corrosion are the use of dis- similar metals, and water intrusion, es- pecially where water becomes trapped against an aluminum surface and remains there for an extended period. Here’s a list of some of the steps Metal Shark takes to prevent corrosion: • We use Tef-Gel on every threaded fastener. Tef-Gel is a PTFE-based fastener lubricant that prevents corrosion by isolating electrolytes from metal surfaces and keeping them from creating a galvanic cell. • We isolate stainless steel fasteners from all aluminum surfaces by using plastic washers between the aluminum surface and the stainless steel flat washers, or plastic shoulder washers between the fastener itself and the aluminum. Never at any time do we allow stainless steel to lie in direct contact with an aluminum surface. • Brass and copper are enemies of aluminum so we avoid these alloys wherever possible. When it is necessary to install a brass or copper fitting, we take extreme caution to isolate it from the aluminum. • Galvanic isolators are always used with shore power connections. • We test the cathodic protection of our hulls with an anode testing probe to make sure anodes are functioning properly. • Any surface or aperture that is prone to water intrusion is embedded in 3M 4200 Marine Sealant to prevent water from getting caught between any surface and the aluminum. • Faying surfaces or any large areas where water could be trapped, including the areas behind collars, rub rails, and rub strakes, are