How to Repair Foam Airplanes

Fix minor cracks and breaks with clear packing tape. The tape allows for a great temporary fix when at the field. Simply apply a strip of tape to the top and bottom of the affected area. Try to limit tape fixes to the tail feathers and other low-stress areas.

Glue stress fractures and clean brakes back together with your foam safe glue of choice. Clean the affected area of any dirt and debris before applying glue. Dry fit the pieces to insure that the parts will remain in alignment after the glue is applied. If you use polyurethane glue, hold the parts together with painter's tape. Place the tape over the joint to keep the glue from expanding out of the joint.

Strengthen bad brakes with scrap wood or fiberglass cloth. Some high stress areas like wings joints and firewall mounting areas need some additional reinforcement. Fiberglass cloth should be saturated with epoxy and placed on top of the break.

Use scrap foam to fill holes. Sometimes you miss a piece of foam or two when cleaning up after a crash. Assemble the parts you have and place the scrap foam under or inside the gap. Trace the gap onto the scrap foam using a fine point pen. Cut the foam a little larger then the gap and sand to fit. It helps if the scrap foam is a little thicker than the gap you're trying to fill; that way you can sand off any trace lines.

Make sure the airplane is correctly aligned. Use a tape measure and measure the distance from the wing tip to the end of the stabilizer on each side of the plane. The distance should be the same on both sides.