OK, here we go. I will be covering the tops of both the wings and stabs with silkspan. The bottom surfaces will be Ultracote. I do this for several reasons the first of course being weight. Second it saves a huge amount of work and third I can put on ultra bright orange that I can see.

I sand all the surfaces with 220 at this point. I don't spend any time on the bottoms as they will get dinged and wet in the finishing of the top surfaces. I have done several silkspan jobs and find the biggest issue is grain showing up after the silk goes on. Normally I fill the grain after the silk goes on, but I am using a different approach this time and it works great. After sanding I applied a medium coat of DAP Fast N Final Lightweight Spackle. I work it into the surface with a credit card. Allow the spackle 24 hours to dry. If you try to sand it sooner, it just balls up. After its dry, I dry sand it with 220.