Canopy Leading Edge Fillet

Before the fiberglass layup of the canopy fairing can begin the plexiglass lip along the leading edge of the canopy must be filled in. So the fiberglass cloth has a smooth transition from the plexiglass to the metal and is not bridging any gaps. A mixture of resin, glass microballoons and grey dye was used. Dye is used to tint the resin from its usual translucent color since the fillet will be visible from inside the cockpit and an opaque look is desired. Microballoons are added until the resin has the consistency of peanut butter and won't flow or creep. The mixture was sealed in a ziplock bag with a corner cut out and used like a pastry chef icing a cake. The microballoon mixture was squeezed out along the leading edge lip then tooled semi smooth with wooden tongue depressors. Once dry most of it was sanded off flush and parallel to the plexiglass. The sanding took hours using 80 and 120 grit paper using small sanding blocks on the sides. Towards the center section I found that stiff foam sanding blocks in various grits can be cut into useful shapes with a sharp knife. The fiberglass cloth bonds better to the scuffed plexiglass and aluminum then to the microballoon mixture which is why most needs to be removed.