sanding

Grew up around airplanes, dad was AF utility pilot and used to own a Cherokee when I was a teen. Despite having quite a lot of flight/aeronautic knowledge I have already learned an amazing amount here and on a couple other forums. Building my first "foaldie" (my own term, lol) with the FT Mini...

Hey everyone, I've recently ween working on a new project involving a covering technique of lining it with strips of delaminated foam. This, of course, is not perfect and I'd like to know what would be the best solution to filling the cracks for future sanding and finishing. Any advice? Thanks