Glueing balsa to foam
I agree with the 3M77 for a plane that sized. I've even heard of people using brown meat packing paper. But for larger I would use ProBond polyurethan glue. Works great, expands like the foam insulation out of the can. But not as much. Fills the voids very well. It sands ok, not as good as I was told by others, maybe its my technique. Its a little hard. But I'll definately use it again. It would probably be too heavy for a .10 sized plane.
Edwin