I found that using trim tape works great for sealing the hinge gaps. Just do like these people were saying, deflect the control surface all the way down, fold the tape in half, lay the tape in the V and then press the ends of the tape down on the control surface and the plane. Works awesome, and will help prevent snapped hinges. And seal the whole surface, on top of hinges as well as in between them. Good luck! - Spool [8D]