Build an Ultra-Strong Rohacell Composite Spar

Many are familiar with applying a thin carbon-fiber laminate to an existing spar to enhance its strength, but you can make the wing even stronger—yet lighter—by using an all-composite spar. The spar has three parts: a top, a bottom and a shear web. The top and bottom parts of an all-composite spar are carbon-fiber laminates. The .007 or .014-inch-thick laminates used for conventional spar reinforcements aren’t thick enough to strengthen the spar sufficiently to make...