"Now that the propellers have been professionally coated with Propspeed, we are confident they will remain clean and efficient until our next docking in two years."
Marine Superintendent, William C Daldy Preservation Society
Built in Scotland in 1935, the William C Daldy is the world’s last hand-fired, coal-burning heritage steam tug of her class still operating commercially today. “The fact that she remains largely original and fully operational contributes to her rarity,” says Keith Ingram, marine superintendent of the William C Daldy Preservation Society, who bought the boat from the Auckland Harbour Board when she was retired in 1977. These days, the Daldy is moored at Hobson Wharf in the heart of Auckland City and steams around the harbor on charters and local celebrations several times a year, including the Auckland Heritage Festival and Auckland Anniversary Day.
Listed as “a historic ship of unique significance and originality, worthy of preservation” on the World Ship Trust’s international register of historic ships, the Daldy is now 83 years old and remains “Auckland’s own” steamship, a living piece of maritime history.
“Because the tug is the last surviving example of her type in the world today—she is still hand-fired, coal-burning, with two massive triple-fired Scotch boilers—hull efficiency is important to fuel burn,” says Keith. “The tug, when steaming, will consume up to one ton of burning coal per hour. This is a significant cost to the Society.”
Why so much coal? The Daldy’s twin triple-expansion engines are likely the largest operating in the Southern Hemisphere, each delivering 980 ihp. Together, they spin 115 rpm at 185 psi to power twin bronze propellers, each weighing 3.4 tons and measuring 11 feet, 9 inches in diameter. At full steam, the Daldy can still run a mile at 13.5 knots, her original sea-trial speed. In addition to the two main engines, 15 more rely on steam to power all manner of pumps, forced draft for the boilers, and a motor for the power generator and two main winches, among other things.
“Today, the tug looks better than the day the Society rescued her from the knacker’s yard,” Keith says proudly. “Credit must be given to the early members of the Society, who took on the role of guardians to preserve and restore the ship so that future generations would be able to enjoy the experience of a real living steamship.”
From the time the Society took ownership, the Daldy has been restored bit by bit, one docking at a time. “Sponsors, trusts and government funders [needed to] see progress and value for money,” explains Keith. “The challenge, then, was to keep improving her while ensuring that the public had reasonable access and could enjoy the experience of being on board.
This most recent haul-out, Oceanmax was among these sponsors, supplying 8 liters of Propspeed - effectively one liter per blade—for Henley Engineering to complete the job. “This ‘haircut and shave’ docking still required a budget of over $130,000”—not factoring in hundreds of donated tradesman and volunteer hours, goods and services. “The true cost of this docking would have been close to $200,000 [NZD].”
This year’s Propspeed application, Daldy’s first, came more than two years after the first attempt in August 2015, which was scuttled by a dock-sharing conflict. Before that, it was “polished props or a variety of coatings from lanolin to hull-hard antifoul paints, with varying success—or not.” Between dockings, the Daldy experienced a massive efficiency loss: “Fouling build-up on the props increased coal burn, and we were slower in the water. The cost-per-hour’s steam in distance traveled increased by about 30 to 40 percent.”
With the Propspeed now on, Keith is looking forward to a return to optimal performance, a comfortable 8 to 9 knots at half steam. “Accumulated barnacles and other marine growth severely impacted the tug’s performance. At the end of our cycle, we had to steam full ahead and could reach only 7 or 8 knots.”
Keith and the Society are grateful for the outpouring of support from the Auckland Council and local businesses. “Getting Oceanmax to supply Propspeed and Henley Engineering to clean and check the propellers is of significant value to the Society and makes our operating efficiencies so much better. We’re very comfortable about the protection we now have underwater,” which also includes 40 sacrificial zinc anodes.
“A dead weight of 365 tons of steel immersed in saltwater is a recipe for corrosion, so we have to take all due care. We’re really pleased to have Oceanmax partner with the William C Daldy Preservation Society to help protect our underwater features and give us operating efficiencies by improved speed through water. Now that the propellers have been professionally coated with Propspeed, we are confident they will remain clean and efficient until our next docking in two years.”
What size Propspeed kit do I need?
The right kit for your needs will depend on the size of the area you’re coating. Our three kit sizes correspond to the following coverage areas:
200ml: up to 0.4m2 or 4.3ft2
500ml: up to 1m2 or 10.75ft2
1 liter: up to 2m2 or 21.5ft2
How does Propspeed work?
Propspeed is a foul release coating, not an anti-foul, so it doesn’t harm marine life. The top coat on the Propspeed system is an ultra-slick surface that marine growth can’t grip. Propspeed’s effectiveness does depend on movement of your boat - the more you use it, the better Propspeed performs. Propspeed sets itself apart from the competition with the exceptionally strong chemical and physical bond between the metal substrate, the primer and the top coat - this ensures that the Propspeed coating actually stays on your running gear.
Is Propspeed environmentally friendly?
Yes. Propspeed contains no copper, tin or any other toxic substances harmful to marine life.
How long does Propspeed last?
Propspeed will last at least a year, but many customers report another one or even two years service life. This depends on what sort of marine environment your boat is moored in, the water temperature, and how often you use it.
Will Propspeed lose its effectiveness if my boat is out on the water for a period of time?
No, provided the only maintenance given to the parts with Propspeed applied is a light wiping with a non-abrasive cloth, the boat can be hauled and launched multiple times, or left out for long periods without affecting the performance of Propspeed. If you are having the bottom of the boat high pressure washed ensure that any Propspeed coated parts are covered to prevent damage.
Can Propspeed protect against Zebra mussels and other freshwater growth?
Propspeed can be used successfully in fresh or salt water. As it’s a foul release, not a biocide or anti-foul, Propspeed relies on a slick surface - it doesn’t matter what sort of marine growth you have, it won’t be able to get a grip.
Can I apply Propspeed myself?
For best results we recommend Propspeed is applied by a trained applicator. See our applicator finder, or or your haul-out facility may already have an arrangement with an applicator.
What is the shelf life of Propspeed
All Propspeed kits have a shelf life of 3 years from date of manufacture.
The date of manufacture should be clearly labelled on your kit and components
What parts on the bottom of the boat can be coated with Propspeed?
Propspeed can be applied to any metal part below the waterline, including propellers, shafts, struts, rudders, trim tabs and through hull fittings. You can also use the clear coat directly on plastic bow-thrusters and underwater lights.
Is Propspeed expensive?
Propspeed may cost more to buy than conventional anti-fouling paints, but the feedback we get constantly from boat-owners is that it pays for itself. By keeping the running gear free of marine growth, not only does it reduce the time spent cleaning at next haul-out, but it reduces your running costs by increasing your speed and reducing your fuel consumption
What sort of maintenance does Propspeed need?
None. The foul release formulation is self-cleaning as soon as the propeller starts up. If required, a light wipe with a non-abrasive cloth will remove any marine growth. When hauling out, ensure the Propspeed is wiped down with a non-abrasive cloth before any marine growth on the surface can dry. Water-blasting, scraping and other abrasive cleaning will damage the Propspeed and eliminate its effectiveness.
Will Propspeed affect the life of my sacrificial anodes?
The application of Propspeed greatly reduces the wetted metal surface and the positive outcome is that our customers are seeing an increase of vessel speed with less RPMs, fuel savings and, the protection from stray current damage resulting in longer sacrificial anode life. It has been observed by our customers that by using Propspeed on their running gear and propellers they have seen a dramatic reduction in corrosion to their underwater metals and that their sacrificial anodes are lasting longer..
How long after application of Propspeed until I can launch my boat?
A minimum of eight hours drying time is required after the final coat. This is based on an average air temperature of 15 deg C, or 59 deg F. If the air temperature is colder than this, a minimum of 24 hour curing time is recommended.