Some progress on the camper. First, bottom side up we see the floor with four coats of paint. Next, flipped over right side up and sitting on the trailer we have 1″ boards gluing in place around the perimeter. Finally, the 1″ rigid foam that will be part of the floor. Later today I might enlist help in cutting the plywood for the top of the floor.
What I will do is get some more Glidden Gripper, which is the go to paint for these projects, and paint the plywood seen in the middle picture and also one side of the foam and put them together. Then repeat with the top side of the foam and the bottom of the top piece of plywood. The gripper, so named because of its adhesive properties will glue it all together. The foam has a lot of compressive strength while the plywood is strong lengthwise. The combination will be strong and light.