Yeah I called them a "cap" in posts 28 and 29. Just use this stuff from Arts. Beware that this stuff is harder than the wood, so you will need to be careful to get it level with the wood routing slot, as it will not sand as easily as the wood, so it will leave a ridge if you are not careful when you do your finish sanding (post 30)

"Gluit" is a highly sandable white glue, made by Pica. Any whilte glue would work, it's just Gluit is my favorite white glue and if you get any on the wood it sands easily. It is great for joining anything on wood covered foam wings (like leading edges, trailing edges, etc)


"Model Magic" is just wood filler, it used to be made by Carl Goldberg. It is just that standard latex based stuff, balsa filler.

On a composite wing however, I use "Split Second"....that is my new favorite polyester filler. That is too hard for balsa and will not sand well in this wood wing application.

Good luck,