Paul Elkins built this lightweight travel trailer for his trip to the Burning Man festival. It has a roof-mounted wind turbine for electical power, as well as a solar cooker and water heater. It weighs only 100 pounds dry, so he can haul it around with his bicycle:
The skin is 1/4" flutted plastic like whats used for election signs. This was riveted and screwed onto 3/4" square aluminum tubing salvaged from an old satellite dish. The base was made of 2x2 fir. The 30" square door frame, made of 1x2's was skrewed to the side panel, cut on the sides and bottom. The upper part was left uncut to act as a hinge. The bed hinges in a lounge attitude. On the outside resides an herb flower box, a urinal funnel (sanicans were a ways off) and 13" wheel barrel wheels on a 1/2" axle mounted with 1/2" square tubing made up the running gear. I used 3/4" steel for the tow bar, A recycled card table for the corner camper supports, and misc this and that. It's whatever I had kicking around at the time, and that's how anyone would have to do it if worst came to worst.
There are many pictures at the link.
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