Only a decade ago, carbon fiber was considered "exotic", an offshoot of aero-space technology, whose cost severely limited its application. High-budget racing yachts found uses for carbon in rudders, spars and space-frames, and occasionally wherever the rules allowed! As this sailing "arms race" accelerated, carbon found its way into hull laminates and, as the technique were perfected, gained acceptance by more builders.

Today, we appear to have reached a saturation point, where "state of the art" means a hull is nothing less than 100% carbon, Kevlar, etc. This trend has caused a huge increase in the price of a competitve design and rendered most of the world's racing yachts obsolete in just a few years. The growth of one-design and PHRF (handicap) fleets is a reaction to this trend, but it is mass production rather than rational, materials utilisation that is keeping the price of these boats down.

When it comes to custom work and bigger boats (over 50 feet), the new standards in construction mean that few owners can compete with the super-rich. This has been well-publicized in the high-visibility races, but also affects regional events. It has been particularly noticeable on the US west coast, where downwind racing for line honors in 70 footers is a well-established class.

A small yard located on the Columbia River in Portland Oregon has a surprising answer to this dilemma. At Schooner Creek Boat Works, the alternative material is wood! In a series of four wooden yachts, all using WEST System epoxy and Klegecell coring, they have demonstrated wood's potential as the original, "high-tech" material. Now their latest project, in conjunction with designer Tom Wylie, promises to make a few more waves among yacht builders.

Since the 1970s, Bay Area designer Tom Wylie has produced an eclectic catalog (inventory) of designs, ranging from the 21', water-ballasted American Express, which won the Mini Transat in 197? to the WylieCat 30, a surprisingly fast, cat-rigged cruiser.

He's also made occasional forays into the grand prix world, with a series of half tonners, and introduced a popular, 24' trailerable keelboat with minimal accommodations - the Wylie Wabbit.

In 1992 his work took a new turn, when Portland, Oregon, boatbuilder and sailor Steve Rander approached him about producing a 70', ultra-light, super-fast cruiser. And if this wasn't sufficiently challenging, Rander intended to build in a wood/foam sandwich and wanted to cruise with just his wife as crew! Wylie, who prefers to keep a low profile in the yachting world, took these demands in stride and turned out the plans for the Rage.

Rander built the boat using his trademark, wood-composite method, dubbed the COVE system -Core-Veneer-Epoxy, and kept the weight down to 20,000lbs. The deck was laid out with no more gear than you'd expect on the average 40 footer, but the Rage proceeded to demolish the Pacific Cup record (San Francisco-Hawaii) in successive races - 1994 and 1996. These successes led to the sale of two Wylie-designed 52 footers to NW owners, built with the same materials as Rage but with more beam for all-round performance.

Steve Rander has been building and racing wooden sailboats in Portland since the mid-70s, using double-diagonal construction and WEST System epoxy. These molded hulls proved to be robust, so Rander began experimenting with the use of Klegecell coring for a crusier-racer he planned to build - the 42' Magic Carpet. The experiment has proved an absolute success - after five Hawaii races since 1984, this yacht has completed nearly 100,000 miles of hard, offshore sailing with no sign of fatigue.

By 1992, Rander was convinced that a wood/foam-core/epoxy combination was the key element for cost-effective, raceboat construction. He therefore chose to develop the method for the 70' RAGE. (Subsequent use of similar, COVE laminates on two 52', cruiser-racers, also drawn by Tom Wylie, proved that this method would produce a strong, lightweight, price-competitive, semi-custom yacht.) The latest project at Schooner Creek Boat Works gives Rander another chance to explore the limits of wood-composite production.

The 42' Magic Carpet was built using double-diagonal 1/8" planking on both sides a 1/2" KLegecell core with three spruce stringers per side. A small amount of carbon fiber was used along the keel and in diagonal strapping to reinforce this schedule, which resulted in a bare hull weighing 1,200 lbs. (Panel weight 2.0 lbs per sq.ft.)

The Rage hull was cored with 1" Klegecell and skinned with 1/8" double diagonal, cedar on the inside and spruce on the outside. Two tows of 12"-wide uni-directional, carbon fiber were applied along the keelson, one at 0 degrees and the second at 90 degrees. The deck is a sandwich of 1/16" birch, aircraft plywood and Klegecell weighing 1.5 lbs per sq.ft. (Panel weight for the hull was 2.13 lbs per sq.ft.)

When a request came for a larger, faster version of Rage, Rander convinced his client of the virtues of a wood-composite sandwich, consulted with designer Wylie, then produced a variety of sample, hull panels. These were tested at the Gougeon Brothers WEST System facility to examine various possible uses of wood, carbon fiber and foam core, seeking the best combination of cost, strength and durability. The tests, using the Hydramat test equipment at the Gougeon Laboratories showed that a re-orientation of the wood fiber would improve stiffness, along a single axis, with a slight weight saving, and also speed up construction.

The modified laminate does require the use of additional carbon fiber to achieve the desired goals of extreme light weight coupled with panel stiffness and strength. The amount of carbon being used, however, is minor compared to what would be required to achieve the same ends without the use of strip planking. In practice, the hull construction has proved to be "very efficient," according to Rander.

The basic schedule has the wood component (1/4" western red cedar strip planking) running fore-and-aft each side of a 1" Klegecell core, covered with two laminates of 6 oz, bi-directional carbon fiber in double-diagonal mode. It weighs 2.08 lbs per sq. ft. and eliminates the need for stringers.

The 77'X 14' bare hull is predicted to weigh around 2,500 lbs, the keel 10,000 lbs and the sailing weight 22,000 lbs. Wylie is optimistic that this will ensure the ability to meet the owner's quest to "set new records throughout the Pacific." By comparison, the record-setting Rage displaces 21,500 lbs, while the latest "turbo-sleds" weigh in at around 29,000lbs.

It's certainly possible to build this design in carbon, Rander agrees, but the cost would be astronomically higher and the competitive life of the yacht would be far shorter. In the last Whitbread Race, for example, many of the entrants suffered excessive flexing and subsequent delamination in the bow sections after an extended period of hard sailing. In laboratory tests, wood, when properly encapsulated in epoxy, continues to demonstrate its natural reslience long after carbon, kevlar or glass laminates have failed.

The spars also emphasise cost-effective use of carbon fiber. 85'mast is a tapered tube with a circular cross-section built by Composite Engineering in Massachusetts using their triaxial braiding process. (This is a more economical method for producing carbon spars than the labor-intensive, hand-layup methods.) Schooner Creek also replaced a standard extrusion, 30' aluminum boom with a lightweight, triangular spar in 1996 to a design, by another Bay Area architect Jim Antrim, using 3/8" ply for the walls, which are reinforced with uni-directional carbon fiber at the stress points.

After the 38 full-size patterns were cut from particle board, they were erected on a temporary base and aligned using a laser. The inner layer of 1/4" cedar planking, laid over a polyethylene membrane, produced a very fair hull. After solid blocking was epoxied into place for thru-hulls and keel attachment, the Klegecell was vacuum-bagged on each side of the hull, in a single step. The core was then faired with long boards and the outer layer of cedar pressed into thickened epoxy, then bagged from the shear clamp to the keel. The WEST System Proset 145 epoxy and 229 hardener was then post-cured at 130 degrees F for 12 hours.

Four, laminated- mahogany, ring frames were pre-fabricated in the shop, along with four foam-core frames for the forward sections. These are securely tabbed into the hull and a pair of 40', wood girders, two feet apart, which contain the engine mount, steel keel-bolt box and mast step.

With this streamlined system proving as fast as he had hoped, Rander sees continuing potential in the COVE system. "The carbon fiber could be replaced by less costly E-glass in less weight-sensitive designs," he points out. "But the best part of the concept is that wood is easier to work with and also has a great resistance to fatigue. When built with modern resins, wooden boats have a very long, projected life."

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