Turn, Turn, Turn

How triumph reinvented the mold.

September 1, 2002

Why would a relatively sane individual look at a Triumph boat and say, “Thank you, Easter Bunny”?

Because the technology the company uses to build its boats can trace its roots to a pioneering chocolatier who in the 1880s forever changed the way Easter bunnies were produced. He had been making solid little Easter bunnies when he realized he could make larger ones with the same amount of chocolate if he poured cocoa powder directly into a closed mold, heated the mold to melt the powder, then rotated the mold so that the melted chocolate spread over the inside. People loved his big bunnies. And Easter hasn’t been the same since. Thanks to Triumph, boatbuilding won’t be either.

Using a similar process, Triumph builds rotomolded plastic boats that are strong, durable, easily maintained, and-believe this-inexpensive. I went to Triumph’s factory in Durham, North Carolina, to find out firsthand how this company evolved rotomolding from making tasty bunny ears to boats that won’t crack when you hit them with a sledgehammer. I spent a couple days there building a Triumph 210 Center Console, hull #335.


From Bunnies to Boats

Boatbuilding has always been slow to change. For our boats, the predominant materials are wood and fiberglass. But now Triumph is whispering a word in everyone’s ear, like the family friend did to Benjamin Braddock in The Graduate: “Plastics.”

In 1946 an industrial chemist was tinkering with one of the early plastics developed during World War II. As his kids chomped their Easter bunnies, he noticed how uniform the insides were. Why not use that idea to make a one-piece tank by pouring plastic powder into a heated, rotating mold?


Fifteen years later, simple rotomolded plastic tanks became commonplace. Then an engineer tried using pulverized polyethylene, which turns out to be tough enough to withstand licks from a sledgehammer. Next thing you know, the process was used to produce all sorts of everyday products, from lawn and garden carts, automobile consoles, and decorative figurines to boat fuel tanks, helm seats, and mooring buoys.

For the next 20 years, builders rotomolded sea and whitewater kayaks, the hulls of which have garnered a reputation for toughness, especially when bounced off rocks.

In 1992 a tank manufacturer in New Zealand started tinkering with the idea of rotomolded 12′-to-15′ outboard skiffs. They turned out to be tough, ran well with modest power, and were inexpensive to produce. These were Logic boats, Triumph’s immediate predecessor. The builders moved to Durham and started mass-producing them. The first writer from BOATING Magazine to test one was asked by the manufacturer to run it into a dock. He did as directed, and lo and behold, the hull didn’t get scratched.


Demand for these tough inexpensive skiffs grew. The company developed more complex molds for a 17′ model and then a self-bailing 21′ center console. I tested both, and they earned my kudos. But there were quality-control problems, and the hulls never had the kind of creamy shine that draws buyers to new fiberglass.

Enter boatbuilder Genmar, which in 2000 bought Logic, then changed its name to Triumph a year later. Quality control has improved, and I’m in town to find out how.

To Have and to Mold


Most boatbuilders start their molding process with gel coat, a thin layer of skin coat, and some variation of fiberglass woven roving or chopped mat. Triumph starts with powdered polyethylene. The powder is finer than granulated sugar but grainier than Sweet’n Low. It’s inexpensive and durable, so it makes tough boats (Triumphs carry limited lifetime hull warranties) that sell for less than most of their fiberglass competitors.

Another difference from fiberglass is that the two-part mold produces a one-piece boat instead of separate hull, deck, and cockpit liner assemblies that must be joined with fasteners and adhesive. The catch: A highly detailed mold is needed to incorporate all the pieces into the hull-deck-cockpit unit, from fishboxes in the cockpit sole to rigging conduits and drains. The quality of that mold is crucial.

The mold for the Triumph 210 CC, originally developed under the old Logic administration, has been tweaked extensively under Genmar. The molds, built by Remmele Engineering of New Brighton, Minnesota, are cast aluminum and machined to produce smooth surfaces. Over time, they have been modified to improve both on-the-water performance and the assembly process.

One example of improvement: Early Logic 210 CC’s ran slightly bow high, a characteristic that made them ride hard in a steep chop. The running bottom carried the moderate-V 19-degree transom deadrise well forward, providing good stability and performance with modest power, but that’s not the part of the hull you want to hit a sharp sea with. Triumph added a slight hook to the running bottom at the transom to correct this. (Trim tabs will let you use the hull’s sharp forefoot to cut those seas open, too.)

Let’s Get to Work

To prepare the mold, I clean both halves carefully with a vacuum hose. Then the molding crew installs several small parts, including copper tubes for the fishbox drains, plugs covered with mold release for the transom’s engine mounting bolt holes, and stainless-steel inserts that will receive the bolts for cleats and ski-tow-eyes. Six small aluminum brackets, bolted into the bottom near the transom, heat up inside the mold. They attract extra plastic to form “kiss-offs,” key structural spots where the polyethylene is solid between the upper and lower molds. Two small fans inside the oven direct extra hot air to the kiss-offs to attract even more polyethylene. A 30″ stainless-steel strap gets set on edge in the bilge to form part of a backbone that ties together the transom and keel. The crew also adds a heat sensor into the transom that will help them monitor the temperature during the molding process.

Once everything is set up, the crew preheats the natural gas-fired oven. They bolt the molds together and insert the supply hose for the powdered polyethylene into an open port in the bow anchor locker. I press a button that starts a pump drawing a premeasured amount of polyethylene (1,100 pounds for this model) from a silo outside the plant into a supply hopper. When the hopper registers the correct weight, I press another button and the white powder flows into the mold. A crewmember rotates the mold twice to check for leaks. Now I press a third button and the three-story oven opens up. The mold moves in. The oven closes. Time to start cooking.

Now the oven begins rolling side to side and rocking fore and aft. The motion for the entire 72-minute, 600-degree cooking process is controlled by a computer. Visualize what’s happening: Polyethylene powder settles on a hot surface in the mold, melts, and adheres. The computer program moves the mold so that the powder is distributed uniformly. Pauses are programmed into the routine to give the polyethylene powder time to adhere. The result is a strong one-piece hull with no hull-to-deck joint, an area of potential weakness on a traditional boat.

After cooling the mold for 38 minutes, the crew opens it, and there, sitting in front of me, is hull #335. All that white powder has become a boat. The team moves it into a rigid, heavily reinforced cooling jig, where it will cool for another 90 minutes. This ensures a precise shape. As it cools, Triumph workers cut off some lacy flashing along a fishing rod pocket in the cockpit, install fuel lines and rigging conduits, and bolt in another stainless-steel strap that extends from the one at the transom forward to where the console will go. They fill all the fishboxes and storage compartments with foam plugs to prevent distortion.

As with fiberglass hulls, adding foam increases strength, deadens sound, and provides flotation. Now the crew checks the pressure in the low-density and high-density urethane foam guns and runs test shots into plastic bags, which they weigh to make sure both are shooting foam of the proper densities. They shoot low-density foam down the hull’s topsides and the outer edges of the transom. Rock-hard high-density foam goes into the center of the transom for structural integration, two buckets molded on either side of it, and the stainless-steel strap. A short shot goes into the bow, too, for both strength and balance.

Sweat the Details

The biggest knock on rotomolded boats was their finish. Even when new, they never had that high-gloss new-boat shine. The truth is that polyethylene will never shine like buffed and waxed fiberglass, but Triumph engineers have worked out a detailing system that comes closer. They also claim that the sun’s ultraviolet rays won’t affect their hulls, so they’ll never turn chalky like fiberglass, nor will they absorb water or develop blisters.

The folks in the detail shop use woodworking tools, handheld grinders, and small planers to remove any flashing from spots-say, where the two halves of the mold join. They buff out those areas with 800-grit sandpaper and wipe them down with mineral spirits. Then they go over the entire hull with a soft pad buffer. Any larger surface imperfections are easy to fix with a welding gun that runs on polyethylene “rod.”

While the detailers are working on #335, a quality-control engineer comes by. Our hull passes inspection. By the time the detailing crew finishes, it looks great.

Now #335 moves to the first of five stations on the assembly line. The process is quicker for a plastic boat since there’s no need to join the hull, deck, and liner. A cart meets us here with all the parts it’ll need to complete the assembly-except the console. The two-person crew beds the rubrail with Rule elastomeric compound, screws it in, and drills all the holes for the rest of the assembly process, guided by drilling jigs. The crew at the next station installs seacocks, the engine wiring harness (Triumph prerigs for all five major outboard manufacturers), the rotomolded polyethylene 70-gallon fuel tank (pressure tested and certified), and related equipment.

Stop number three brings the anchor roller, several Starboard plastic hatches with Triumph’s distinctive, deeply scored nonslip surface, plus neatly bundled and supported wiring for running lights and pumps. At the fourth station is the helm seat/livewell module and console. They fit together ingeniously, locked by molded lips to the sides of the bilge and fastened with large stainless-steel screws and fender washers. The console includes a clever hinged upper section that provides easy access to wiring and rigging, with space below for the batteries and switch, plus a large stowage compartment that can be locked. On top is an electronics box and several handy trays for small gear like sunglasses and cell phones, plus cupholders. If the boat is getting a T-top, it goes on here. The final station sees application of Triumph’s hull graphics, cushions, coaming bolsters, and a cooler seat in front of the console. Then it’s off to the shrink-wrap shop and from there loaded onto a tractor-trailer for delivery and a happy life on the water.

It’s funny that rotomolding should have progressed from a material made to be broken apart and eaten (chocolate) to a substance that is known for its toughness. Chocolate bunnies come and go every Easter, but #335 is going to be around for a long time.

For more information, contact: Triumph Boats, 100 Golden Dr., Durham, NC 27705, 800/564-4225,


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