February 9 - 27, 2009 ...  After mounting the fairing to the wingtip I Clecoed everything together for a final check on the fit. You can see that I also mounted the Kuntzlemann NAV/Strobe unit to get a feel for how everything is going to come together.  I was really happy with the fit and finish. So I removed the strobe unit, and rough sanded the aluminum wingtip with 60 grit sandpaper. 

 

After wiping the entire assembly down with a tack cloth, I filled the seam with JB-Weld. It didn't  take much because the wingtip fits pretty nice up to the wing skins.  (A much better fit than what I would have got with the fiberglass tips!)

 

Next came the long process of feathering in the NAV/Strobe fairing with fiberglass Micro-Spheres. The first coat came out pretty sloppy because I mixed the stuff a little too soft. That took a lot of sanding to correct. But starting with the second coat, I was getting the "hang of it."  The secret is to add enough Micro-Spheres that it ends up in a consistancy like thick peanut butter. It softens a bit when you spread it out. Another change I made was I used a "Fast" curing hardener rather than "Medium"  curing. I applied the Micro-Spheres using plastic body filler squeegees, purchased from an auto parts store.

 

After applying each layer of Micro-Spheres, I would let  the filler cure for 24 hours, then I would sand it into shape with a 100 grit sanding sponge. It took 6 layers of Micro-Sheres to get the shape I was striving for. With the final coat, I sanded everything smooth with a 220 grit sanding sponge. The wingtip is exactly like I want it now, so I masked off the rest of the wing, and applied 3 coats of primer, sanding between each coat with the 220 grit sanding sponge. The photos below show the final results.