Ultra Rocket Filler is perfect for filling body tube seams and hiding imperfections in balsa and plastic parts. It can also be used to make fillets where your fins join the body tube.
Ultra Rocket Filler is epoxy-based and is very lightweight and easy to sand.
Just mix two parts from the larger container to one part from the smaller one until the mixture is evenly colored and has the consistency of cake frosting. Apply the filler with a squeegee (a piece of cardboard or cardstock works well). Let the filler dry overnight before sanding.
Ultra Rocket Filler comes in two containers totaling six ounces.