At first glance, a brightly-colored kayak or trimaran slicing through the water looks like a simple thing to make — merely a cigar-shaped, oversized, watertight plastic cylinder.

Not so, says Andy Zimmerman, president of Trinity, NC-based Wilderness Systems. While the product may look simple, the molding and fabricating process takes creativity and a lot of skill.

With a hydrofoil-assited trimaran, the WindRider Rave's polyethylene hull knifes through the waves, rather then lifting over them.

Zimmerman and his partner, John Sheppard, learned that lesson the hard way. The two began making kayaks in Zimmerman's back yard a dozen years ago. But, because there are only a handful of companies in the United States making the product, there is no general body of knowledge to draw on, Zimmerman says. "So you go by the school of hard knocks."

The two graduated with flying colors, and it's been smooth sailing for the company ever since. Today, Wilderness Systems employs 130 people to mold and fabricate more than 25,000 recreational boats a year, mostly kayaks sold under the Wilderness Systems and Trinity Bay labels. Three years ago, the company diversified, adding the line of WindRider trimarans for sailing to its product offerings.

The kayaks are sold worldwide through sales brochures and retail stores, with more than 400 stores in the United States selling the models. The boats range in length from 8 feet to 21 feet; the latter are touring kayaks used for extended travel.

The first step in the rotational molding process is pouring the powder into aluminum molds which are designed and manufactured in-house. The molds are then put into a 500F oven and rotated, forcing the melted plastic onto the surfaces. A rolling, rocking motion is used to force the polyethylene down into the ends of the hulls.

Kayaks + Canoes = Confluence Wilderness Systems recently merged with well-known canoe maker Mad River Canoe. The combined company, known as Confluence Holdings Co., posted 1998 annual sales of more than $20 million. The new company ranks as possibly the third largest canoe and kayak manufacturer, says Andy Zimmerman, president of Wilderness systems and CEO of confluence Holdings. Zimmerman's partner at Wilderness, John Sheppard, is also vice president of Confluence. Charles "Chach" Curtis continues as the president of Mad River Canoe. Wilderness Systems and Trinity Bay kayaks, WindRider trimarans and related accessories continue to be manufactured at Wilderness Systems' plant in Trinity, NC. Mad River canoes and Voyager accessories are made by Mad River in its Waitsfield, VT, facility.

"Polyethylene is a very even-forming plastic," Zimmerman says. "You shake and bake. You take it out of the ovens, and you have a boat."

When the process is completed, the fully-formed kayak is removed from the mold. After cooling, any imperfections are corrected with a hand-held heat gun and deburring tool.

Another area of the plant is devoted to vacuum bagging. According to Zimmerman, vacuum bagging is a higher-tech process than rotational molding, which takes a lot hand skills. A mold, from which one half of the kayak will be shaped, is made from a plastic plug or model. Its interior is spray-painted with a gel coat using Binks spray guns. While the coating is still wet, the composite is laid into the mold. It is then placed into a bag, and vacuum is used to compress the composite to the mold.

The two halves of the composite kayak are joined by fiberglass seam tape or Kevlar tape and resin, and covered with a shiny gel coat finish.

Zimmerman says Wilderness is also looking at vacuum forming the composite kayaks, which would allow the company to use lighter weight materials. According to Zimmerman, "the lighter the better," with regard to the kayak's weight because it is often carried by one person.

This interest in vacuum forming composite kayaks may have also resulted in part from Wilderness Systems' recent merger with Mad River Canoes (see sidebar, page 19), which uses this technology to form its canoes. Wilderness Systems already has the capability to vacuum form ABS into seats, using a modified PVI machine.

Because the boats are formed as enclosed cylinders, they have no opening for the cockpit, the area where the rider will sit. A hand-held router from Black & Decker is used to cut the opening before the kayak is moved to the assembly area.

In the assembly area, the kayak gets the refinements that make it practical and comfortable for a water traveler. The company offers accessories for a wide range of users including "young and old, men and women, physically challenged. Everybody is kayaking now," Zimmerman says. "We've got a generation that's looking to be active outdoors."

For stability, many molds include keels as part of the design. Seats are attached to a plastic foam support with a Hysol hotmelt glue gun and Hysol Superpac Maxistick glue before hand insertion. The seats are padded and adjustable.

Electric-powered pneumatic drivers and drills are used to attach bolts for thigh strap fasteners and metal "pad eyes" for bungee cords.

Openings for various hatches are routed using portable routers. Wilderness uses jigs, templates and guidelines to aid in the precision cutting of the hatches. The covers for many of these hatches are vacuum formed from ABS in a modified vacuum forming machine.

Storage sections of bulkheads, used in long-distance touring kayaks, are fashioned from minicell foam blocks cut to size with an Omaha Industrial Tool bandsaw. The bulkheads are then glued into place with the Hysol glue and glue guns to make the compartments water-tight. Floatation bags will be placed in these compartments.

While precision machining is important, equally vital is aesthetics. For this reason, an extensive quality-control program is in place at Wilderness Systems, with Kerry McMahan acting as supervisor and trainer of this department.

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Plastics Machining & Fabricating
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