Make a male mold out of whatever, Wrap the mold with saran wrap. Take as many pieces of 1/32 balsa as you want for the thickness. Wet them down with water with a little simple green added. As soon as they become limp and fexable, stick them together with titebond(don't over do it) and fold them around your form. Wrap tightly with strips of an old bedsheet and let dry. Cut out supporting little riblets and glue inside, then cap the back with a strip of appropriate thickness sheet. You have a light, strong, stiff leading edge.