I bought a roll of clear Monokote and cut strips about 1"or 1 1/4" (The length of the ailerons) and seal the bottom of the wing. Hold your wing upside down and push the aileron as far as it will go. Fold the Monokote the long way so it looks like a "U" from the end and tuck it in the gap of the aileron. Seal it down and now you have an invisible sealed control surface.