Work on the wing panels starts with the layout for the sub-ribs. I prefer to use a trailing edge sub-rib to add strength that spot where everyone likes to pick up the plane for you. The traditional sub-rib is located near the end of the wing socket. The slots for the two sub-ribs can be cut using several methods (band saw, hot wire, hand saw).

Test fit the sub-ribs (they should not fit too tight) and the wing tube socket. Be sure to cap the end of the socket before gluing in place. Epoxy or polyurethane glue can be used to glue everything in place. Be sure to get full coverage on all surfaces of both the tube socket and the sub-ribs. I used wax paper around the areas of the two sub-ribs to prevent gluing to the shucks.