1/2" x 1/4" caps glued between the ribs and also flush with the tops. Whilst this was curing I measured and cut all the 1/4" x 1/4" aileron diagonals. Epoxying the diagonals and holding them in place took some time to get right because they wanted to slide out of alignment. The best technique was to put the clamps on the ribs and use the handles to apply pressure holding the diagonals to the underside of the gussets. At the diagonal/cap junction, the body of a clamp holds the timber in place stopping it from sliding away from the aileron.