For three years now I blew off fitting the fiberglass rudder bottom. Now, I have no choice since it is on the short list of things to do. So the problem is, “how the heck do I bolt this light on”? Seems like I was not the only one wondering. Searching the archives of the usual places turns up a variety of solutions, some of them good, some overly complex.
My goal with this particular piece of fiberglass is to permanently attach it to the rudder bottom. This means that the light must be easily removable from the outside in order to be serviced. The obvious answer is to slap a couple of nutplates on and be done with it. However as you look closer, that is more easily said than done.
The little pod that Van’s molds in to this piece is scarcely big enough to hold the Whelen combo strobe/position light. It is just about physically impossible to cut a hole for the light and for nutplates, then actually rivet nutplates directly to the fiberglass. What I did instead, was to create a plate out of some scrap aluminum sheet in the same shape as the mounting surface of the fiberglass, attach nutplates to that plate, then attach the plate to the fiberglass. Simple, fast and works great! It also allowed me to use a decent sized #6 nutplate and screws.
Step 1. Get some aluminum sheet from your trim bundle and trace the outline of the rudder bottom light mounting area. Use your ruler to draw some lines and mark the center.
Update: I found later that the epoxy did not bond well to the metal plate and it snapped off quite easily. Not wanting to do any more glass work on the already painted rudder, I drilled two additional holes on each side of the plate through the fairing. I then took a couple of “U” shaped pieces of stiff wire and put them through, bending the legs flat on the inside of the fairing (much like a large staple). If I had to do it over, I would glass over the edges and feather them into the fairing. That would insure the metal plate would not escape, and it would provide a nicer transition to the light housing.