By MACK PHILIPS

Many readers have requested plans for building one, but we felt such a project should have a special feature not available in the many fine commercial models that range in price from a basic $300 sleeper to fully equipped luxury rigs costing nearly $3,000.

I, too, wanted to build my own camper for family vacations, but I hesitated to invest in a vehicle that I'd be able to use only once or twice a year and which would take up year-round parking space - especially since I'd need another trailer for hauling jobs.

My Solution: Build a detachable camping unit that could he mounted on an existing trailer chassis. If you already own a boat or bike trailer, you can easily adapt my design to fit it. If you're starting from scratch, you can buy a bolt-together trailer chassis (I chase one from Sears' catalog, but many others will do the job) and adapt it to additional uses.

The camper body detaches from the chassis in half an hour - the time it takes to jack it up, unplug wiring and remove a handful of bolts. Since the camper is basically a flat bottom box, you could insulate the floor and mount it on skis for a wintertime camper. or even put it aboard a motorized raft and have a waterborne shelter.

How It Works: Erected for use, the foam-plastic top (reinforced with glass cloth and resin) is supported on four hinged conduit corner posts. Part of the raising load is counter balanced by a pair of heavy screen door springs at each hinge joint. Should those springs weaken in time, they can be replaced for about a half-dollar each.
The tent portion of the camper is permanently fastened around the inside of the hardtop, and it all tucks under, storing compactly, when the tamper is folded.

The inner portions of both bed frames are a fixed part of the body. The outer portions hinge out to make a portable bedroom (for four) about 12' wide. The tent is stretched over the bed frames, and held to the body and frames with snaps and elastic shock cord. Center head room inside is about 6 ft. 2 1/2 in.

Folded, the camper is sealed weathertight for travel or storage with weatherstripping around the door and under the edge of the hardtop.
 

Choose a chassis of at least 1,000-pound rated capacity (our trailer with Sears chassis, loaded with essential camping gear, weighs about 750-800 pounds), capable of being safely towed at highway speeds.

To give adequate support to the camper body, a narrow chassis such as a boat trailer with wheels outboard of the frame could be modified by adding bolt-on steel-angle outriggers to the frame rails.

For maximum stability, a trailer should have about 10 to 15 percent of its total gross weight in the form of a tongue load. On a unit of this size, you wouldn't want to exceed 125 pounds. Knowing the camper body will weigh a pretty evenly distributed 500 - 550 pounds, you can plan on where to position it on a chassis

How To Go About Building: Recognizing that dimensions and procedures may change with the size and materials you choose, here is how to go at the project.

Saw the 3/4" exterior plywood for the floor. Widthwise it takes a full sheet plus about half another. Ends, and the remainder of the second sheet are used for raw panels, door, gussets, wheel wells, etc. Join floor pieces with a spline joint, using 3/8 in. plywood as the spline.

Cut out openings for wheel wells, allowing an inch clearance all around for oscillation. Well depth (2 in. in our case) is calculated on the basis of the height that the tire could come through the floor if the spring should bottom.

Drill 7/16 in. holes around the top flanges of the frame for bolting on the body. We used 18 bolts, locating one hole as near each corner as possible and evenly spacing them around.

Lay the chassis upside down on the floor and mark frame hole locations. At the same time, drill and cut four pieces 1/8 in. by-1/8 in. by 1 in. steel angle to fit across the floor to add rigidity and support the floor when the body is undecked. Drill holes for Tee nuts. Counterbore these holes from the top side so the Tee nut flanges can be driven flush with the floor.

The 4-by-8 sheets of 3/4 in. exterior plywood make the bed frames - one bed from each sheet.

Glue and screw the preassembled sides and ends to the floor. Use waterproof resorcinol glue for all gluing on the camper. Before adding the inner "benches" that form the fixed part of the bedframes, drill the floor corners for the telescoping jack housing conduit. Fit the door, leaving a gap at the piano hinge for the 3/16 in. weather stripping to be applied later.

Regular boat-glassing polyester resin, mixed with a catalyst so it will harden, is used to "glass" the top. 
Three sheets of urethane make up the top. The fourth sheet is cut into strips (using a utility knife) for the side and ends. Make the top about 1/8 in. larger in each direction than the body. Strip back the glass cloth and insert l/2 in. plywood plugs where corner-post bolts and latches will be. Glue (with resin) 3/8 in. plywood strips to inside surfaces of side and end pieces. When set up, cover with 6 in. cloth tape. Cut the three top sheets to length and glue a wood rail strip down the center of each.

Set the sub-assembled side and end pieces right on top of the body. Apply resin at joints. Nail plywood to plywood at comers with finishing nails. Use masking tape to hold plastic together while curing.

Cut scrap plywood the same shape as the endpieces to give temporary support to top sheets, as shown in the photo. Bevel edges of top sheets to fit well at center joints. Apply resin at all joining surfaces and tape in place.

When cured, apply resin to the rail strips that hide the joints in top sheets, tape them in place, and turn the top upside down on a flat surface. Nail through the foam near the edges and into the rail strip, using large headed plasterboard nails to pull the fairly limber foam into full smooth contact with the rail strip.

Bevel all foam edges topside with a knife and round them smooth with coarse sandpaper. Leave the bottom corners of the top square about 1 1/2 in. up for application of molding.

Apply resin and glass tape over the rails (6 in. wide), and all edges and joints inside and out (2 in. wide). Glass in corner-reinforcing plates. Fill any objectionable voids with epoxy putty.

Give the entire top a full coat of resin to bond the cloth to the foam. Sand out any rough spots and feather the tape edges. Apply another complete coat of resin and sand completely smooth. Paint the entire top with two coats of automotive enamel, sanding between coats. Priming is not required.

Drill support-rod bolt holes, install molding, latch plates, lifting handles, and reflectors. Apply pressure-sensitive weatherstrip around the edge under the molding.