RC planes have movable control surfaces that allow the pilot to change the flight path. The typical movable surfaces are elevator, rudder and ailerons. To make the surfaces movable the hobbyist must install hinges. There are different types of hinges for different applications.
Pin hinges look much like door hinges. There are two sections that interlock, and a pin locks the sections together while allowing them to move. Pin hinges are very strong and can be installed with pegs to add strength. To peg a hinge, drill a hole through the hinge arm and glue a toothpick in the hole after the hinge has been installed. The toothpick is later trimmed and sanded to be flush with the control surface. The peg prevents the hinge from pulling out of the surface to which it is attached. Pin hinges are used in larger gas-powered planes and are typically installed with epoxy glue.
Iron-on hinges are made from the covering material that is ironed on the plane. The hinges are made of two strips of material bound together so that one side of the heat-activated glue on the material faces up and the other side faces down. The hinges must be installed in pairs, one side to the movable surface, the other to a fixed surface. These hinges are used most commonly on elevators and rudders. Attach one hinge end to the top side of the fixed surface, the other hinge attaches to the underside of the movable surface. The second hinge must be installed the opposite way. These hinges are very light, and you can keep the gap between the fixed and movable surfaces very close. The hinges are good for smaller, electric-powered planes.
Tape hinges are usually made from a strip of clear packing tape. The tape is applied to both the fixed and movable surfaces at the same time. Apply tape to the top surface when it is deflected fully down. Another strip of tape is applied to the underside of the surface when it is fully deflected up. These hinges are limited to electric planes made of foam. Make sure to check these hinges frequently as the tape tends to lose adhesion over time.