I found this thread while looking up to see if anyone had actually built what I am planning. The rough sketch by GPW is almost exactly what mine looked like! (Save I have the back stay wide and round down more similar to a typical hatch setup rather than tip into a cone tail...). I think I have discovered a method of manufacturing that is easy and effective. I plan on making my ribs with 1/8" ply arc about 1" wide and have it 'T' to the outside of the rib that has a 1.5" wide strip of ply. I then will make it like a cedar strip canoe, but with 1/8" ply; not even bothering to edge glue it, just stapling it to the ribs. (I have a pneumatic stapler...) Once the exterior is formed I will cut out the doors and windows and make their hatch trims and install them. Then have a company spray CCSPF (closed-cell spray polyurethane foam) on the inside about 1.5" deep. I will also have him spray a few of the plywood panels stand alone for my future countertops and cabinets (Just 1/2 thick foam with 1/8" on either side). The inside will have a few pex pipes run for electrical chases prior to the spraying. Finishing the interior was the hard part to figure out, but I think I solved the problem. I will sand it with my 7" sander/polisher and fair it out smooth with 80grit paper. Should go pretty quick; I have a good steady hand with that sander. Then I will mix 1:3 parts Elmer glue:water and take torn pieces of heavy duty rosin paper and paste it over the walls for the finish. I plan to then take a road atlas and cut it up and do the same for the wall paper and make it a living collage of our adventures with pushpins and little pictures all mod-podged to the walls. I may polyurethane it, but if I am going to add on to it over time I may just leave it with Elmer's glue.
The hard kicker I am trying to solve now is the convex window I want on the front top. I want to do an argon filled polycarbonate/acrylic blend triple pane window (acrylic/polycarbonate/acrylic) about 4 foot in diameter in the top front area so we can see the stars at night. I am contemplating the ability to form them into a convex shape through heat guns and mold forms...I think I have solved all the other issues... (Vertical side hatch seals, hatch seals, constructability, trailer attachment, location of everything, size, etc.) Here is a quick Solidworks picture of my rib system. I will post my graph paper drawings soon. I have done further Solidworks depictions on it, but there is an error in the lofting of the surface and I don't have the time to solve it now, so you will just have to imagine that image yourself.
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