Splinter power

KZN’S wooden replica of a 1964 Ford F100 used to be quite unique, but now Joe Harmon has lifted the bar with his Splinter — the first high-performance, mid-engined supercar built from wood composites.

Harmon, a design graduate of North Carolina State University, displayed the latest incarnation of the Splinter at the Essen Motor Show last week. He led a group of fellow students to build the first Splinter in 2007 as a graduate school project and his company Harmon Design has since improved non-stop on the model they first displayed in 2008.

“Wood is our only naturally renewable building material; it takes an extraordinarily small amount of
energy to produce and is totally biodegradable.

“With a better strength-to-weight ratio than steel and aluminum, it can be made into a lot more things than people tend to give it credit for.

Joe Harmon and design professor Bong Il Jin

“We wanted to push the line on what was considered wood’s limitation as a building material while fulfilling a lifelong dream of designing and building a car from scratch,” he states on his website.

In his Splinter, the body and chassis, along with large percentages of the suspension components, wheels, interior, and other details have been made from wood. The body is made from woven strips of cherry veneer with a balsa core.

“We carved a buck by hand from solid redwood blocks and made a set of female molds from it. These molds were used in conjunction with a vacuum-assisted resin-transfer process to form the wood veneer body panels,” he said.

The wheel centres are made from rotary-cut oak veneer, covered by a walnut sunburst on the outside face and a cherry sunburst on the inside face.

Each wheel consists of over 275 individual pieces.

The chassis is made from a series of bent and molded laminates which were secondarily riveted and bonded together.

A custom mould was built for every component of the chassis, and these components were formed, fit, trimmed, and bonded together to comprise the overall structure. To achieve the compound curves required by the body design, the team wove strips of veneer into a cloth.

Two looms were designed and built by the team to generate this cloth material. This innovation greatly increases wood’s utility in composite construction.

The inspiration behind the Splinter was a WW2 airplane called the De Havilland Mosquito. Equipped with two Rolls-Royce V12 engines, it was the fastest piston-driven plane of its era, and was made almost entirely out of wood.

As such the Splinter has an equally powerful engine — a seven-litre small-block V8. With an eight-throttle-body intake manifold, a camshaft ground specifically for our application, and a custom-built crossflow exhaust system, we expect it to make close to 700 bhp.