RE: hot glue
I have actually used hot glue to assemble foamies made of fanfold insulation foam. Of course i used epoxy for mounting motor sticks and LG plates and i even stuck down the servos with it, but i used all hot glue to attach the side stiffeners, wings and horizontal stab. The glue is pretty tough b/c i accidentally switched the throttle reverse switch while the esc was armed and sent my newly completed plane nose first into the dirt. it broke foam, but not at the glue joints