Working On Fiberglass Tips

Here, I'm working on the fiberglass tips of the right horizontal stabilizer and elevator. I wanted to get the back side of the stabilizer tip to be concave to match the convex curve of the horn on the elevator tip. I used some of the green flower arranging foam from Hobby Lobby that I cut about 1/2" inch thick and then pushed the tip down onto it like I was cutting out cookies. The foam was only $1.77 and should be enough to do all the empennage. Plus, I didn't like the idea of buying a 4' x 8' sheet of insulation foam at Home Depot and throwing 95% of it in the trash.

I then used folded paper as a spacer taped to the elevator horn with sticky backed sandpaper on the leading edge.

I used the leading edge of the elevator horn as a sanding block to shape the green foam to the perfect concave shape with a consistent gap. Then I removed the tip and layed several layers of fiberglass over the green foam. The resin didn't stick to the foam and it was easy to chip out after it dried. I then filled the inside of the new fiberglass layups with several more reinforcing layers like shown in Vans' instructions. I can't imagine an easier or more accurate way to do this so I'll do the same with the left side and the rudder and vertical stabilizer.