Obtain a trailer for the camper. Sketch a plan based on the size of the trailer. Retrofit the trailer by welding four corner gussets and 12 welding chassis tabs. Weld six tabs along the sides of the trailer. Secure one-eighth-inch-by-one-fourth-inch aluminum straps, 16 inches apart across the width of the trailer with screws.
Construct a 2-inch-by-4-inch subfloor frame around the trailer’s perimeter. Mark the locations of corner gussets and the chassis tabs on the frame and drill the holes. Attach the frame to the chassis with three-eighths-inch diameter, 3 1/2-inch-long carriage bolts.
Create a template for the camper’s walls out of cardboard. Place the template on the back of three-fourths-inch exterior plywood. Trace the outline and cut the pattern. Repeat the process and fabricate the other side wall. Sand the edges of the sidewalls with No. 80 grit coarse sand paper.
Mark the dimensions for the door on the passenger side wall and window opening on the passenger side. Cut with a jigsaw. Apply construction adhesive along the side edges of the subfloor frame and lift the wall in place. Use the carpenter’s level to ensure a straight and level installation. Predrill the holes for the screws and squeeze construction adhesive into the holes. Secure the wall with No. 14 2 1/2-inch wood screws. Fill screw holes and any knots in the plywood with wood filler.
Measure the opening between the two walls. Cut two three-fourths-inch-by-1 1/2-inch pieces of lumber. Secure the two piece of wood together with construction adhesive, which creates a 1 1/2-inch square roof bow.
Mark along the perimeter of the wall lines 16 inches apart. Count the number of lines on one side wall and fabricate that number of roof bows. Spread construction adhesive on the end surface of the roof bows and secure them between the walls with #8, 2-1/2-inch long drywall screws.
Glue two sheets of 1/8-inch plywood together. Apply adhesive to the roof bows and staple the plywood in place. Follow the manufacturer’s installation instructions for applying a fiberglass cover on the sidewalls and the roof. Install fenders or other accessories.
Follow the manufacturer’s instructions for framing and installing a roof vent. Secure 1-inch thick foam insulation between the roof bows and on the walls with the proper glue. Attach one-eighth-inch plywood to the roof bows and walls.
Measure the area between the frame. Cut a piece of quarter-inch-thick plywood and laminate fiberglass to both sides. Screw 1-inch wide strips of lumber to the metal straps installed earlier. Place foiled faced rigid foam insulation between the boards. Screw a half-inch piece of plywood to the boards. Apply silicone caulk around the edges of the floor.
Complete the camper by installing the window and door. Furnish the interior, including storage, sleeping accommodations and other accessories in accordance with the plan.
