SOS! Texas Coatings Team Saves Sinking
Maritime Museum Ship

By  Jack Innis With Terry Tilton

Mariners have rallied to the call “SOS,” Save Our Ship, since time immemorial. But a recent SOS from a San Diego-based ferryboat resulted in the vessel’s salvation by a Texas coatings team.

The 280-foot, steel-hulled, historic Berkeley serves as a floating museum and waterfront headquarters for the San Diego Maritime Museum. But they say rust never sleeps, and Berkeley, the finest surviving ferry on the West Coast, was sinking.

Built in 1898, Berkeley ferried passengers between San Francisco and Oakland for decades, but became famous for its role in the 1906 San Francisco earthquake. During that crisis, Berkeley worked around the clock for days, transporting survivors to Oakland, and returning with medicine, food, clothing, and fire fighting equipment.

Now Berkeley was facing a crisis of her own.

“Berkeley is 100 years old, made of steel, and had quite a few strikes against her,” said Maritime Museum executive director Ray Ashley. After a fix from the 1980s began deteriorating, it became evident she was rusting from the inside out. Maritime Museum officials began looking at possible solutions. The traditional fix is to weld new plates, but that solution was cost-prohibitive for the museum.

Ceramics to the Rescue    
Responding to an SOS sent throughout the boating community, Bill Kraus, an avid boater, tossed Berkeley a life ring.

“I first heard about CeRam-Kote myself in 1997 and brought the product to San Diego, almost as a hobby, for use on pleasure boats as an alternative to copper bottom paint,” said Kraus, now a CeRam-Kote salesman and technical representative.



CeRam-Kote is a 100% solids, modified epoxy that is loaded with 60% or more micron-sized ceramic particles. CeRam-Kote’s sprayable grout version (SPG) serves as a high-build corrosion barrier ideal for high-abrasion, erosion, and corrosion environments and has seen service on offshore oilfields and ship hulls.

However, few non-profit organizations have the cash reserves to embark upon such a costly and ambitious project, and the San Diego Maritime Museum is no exception. So an SOS was broadcast to scuba divers, tugboat operators, shipyards, sand- and hydro-blasters: Send your best men and your lowest possible bids.

One Stubborn Prep Job
The project launched when scuba divers plunged overboard while Berkeley was still at the pier on San Diego Bay.

“Berkeley’s hull was riveted together 105 years ago with 3/8” steel,” said Terry Tilton, longtime Maritime Museum docent who happens to work for CorrPro, a coatings company in San Diego. “Her last dry-docking was 60 years ago, and the diver inspections confirmed that there was major pitting and an enormous amount of marine growth on the hull.”

Since Berkeley is a non-operational floating museum, her undersides are not periodically cleaned like most other vessels. The dive team began initial preparation by scraping away tons of soft growth that had accumulated over the decades. They also took careful measurements so shipyard officials could build a suitable cradle for her at the dry dock.

The ferryboat was then towed to Southwest Marine, a nearby shipyard, and positioned adjacent to the floating dry dock vessel, Diligence. It took six hours to flood Diligence’s chambers so Berkeley could squeeze into her cradle, leaving one foot to spare on either side. With Berkeley on blocks and secured, Diligence began pumping water from her chambers. Four hours later, Berkeley was high and dry.

Up the Psi
To avoid contaminating air or water while working on a floating dry dock in San Diego Bay, Berkeley was wrapped in a sheath of plastic. Action Tank Cleaning Company brought in a water-blasting crew to attack the growth on Berkeley’s undersides. But the going was slow.

“The first real problem was that we failed to appreciate the difficulty of removing 30 years of bottom growth,” said Ashley. Stepping up the pressure little by little, the crew found the best results were obtained at 35,000 psi. Being careful not to slice through the hull with the pressure wands, the crew knocked down the one-inch thick marine growth. Then the sand-blasters were called in.

“After weighing the advantages and disadvantages, abrasive blasting to NACE No. 2/SSPC-SP10 near-white metal became the method of choice,” said Tilton. “This provided a better guarantee to meet the 3-5 mil requirements for an anchor profile.”  

The sand-blasting crew consisted of six blasters working several sections at a time. Wearing coveralls with wrists and ankles taped, the men donned blast hoods and attacked the hull with 30 mesh Sharp Shot from Minerals Research Company.

They blasted with 100 psi at the nozzle ends, fed by an Ingersoll-Rand 1300 air compressor for pressure. Sand was fed from a 40-ton Key Equipment blast pot.
When the hydro- and sand-blasting stopped, 6,000 tons of barnacle growth and flash rust had been knocked from the vessel’s undersides.

Timid Inspection and Massive Priming
After sand-blasting, wary museum officials inspected the hull. “We were holding our breath, not quite knowing what we’d find,” said Ashley. “The hull was peppered with more than 5,000 pits, some the size of dimes. In one spot, where the blasting blew through a plate in the engine room, you could see the hull was paper-thin.”

A crew from the Maritime Museum filled the pits one at a time with Splash Zone, a solvent-free, self-priming patching compound. While this was happening, Southwest Marine coordinated the attack on larger holes and other problem areas.

“We really used our whole arsenal on Berkeley,” said Randy Butler, project manager for Southwest Marine. “We drilled and tapped bolt holes and threaded bolts into some areas where the pits had nearly eaten through the hull. One area had a 10” x 2” crack. Other areas looked like Swiss cheese.  There were only a few gas-free areas where we could weld.”

Butler describes “gas-free” as clean atmosphere in and around the area a welder wishes to work. “You’ve got to know what’s behind the area you’re thinking about welding. For example, in a lot of places there was foam inside Berkeley’s hull. If someone mistakenly puts a torch to an area like that, they could set a whole ship on fire.”

Antique Ship Receives State-of-the-Art Coating
When the patching was complete, the hull was inspected for the presence of chlorides and other chemicals and deemed ready for coating by the team from Texas.

Along with the coatings crew, CeRam-Kote flew in a 50:1 Graco King plural-component spray machine and a supply of SPG. After ensuring that the substrate was dry and that the ambient relative humidity was less than 85%, Kraus and his Texas crew began spraying at 8 p.m. with the idea of being done by daylight.

They donned jumpsuits, ski-masks, respirators, and rubber gloves. In 10 straight hours, they applied an even coat of grout to a depth of 40 mils. Officials from CeRam-Kote and the Maritime Museum took periodic measurement with a MikroTest #3 dry film thickness gauge to ensure adequate coverage.


The crew finished spraying by daybreak and returned to Texas.

The dry dock was then cleared and Berkeley re-floated briefly in a procedure called “bumping,” to reposition the vessel to access the spaces under the supports that touched the hull.

After Berkeley was bumped, the sand-blasting crew returned and brought the previously untouched spots to NACE No. 2/SSPC-SP10 near-white-metal.

Shortly thereafter, the Texas coatings crew returned to perform touch-up work and to fix the holidays detected by the crew’s Tinker & Razor M1 set at 62.5 volts and 80,000 ohms.

Due to extensive corrosion and pitting, a second coat was applied to approximately one-third of the hull. In all, nearly 500 gallons of SPG were used. After two days of touch-up, Berkeley was allowed to dry overnight and was returned to her museum headquarters berth at North Embarcadero on San Diego Bay.

With Berkeley saved, Maritime Museum officials won’t be broadcasting another SOS anytime soon.
 

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