Step 1: Trailer
I bought a Harbor Freight 48" x 96" trailer on sale for $300. I'm not sure what the original price was but Harbor Freight always has sales going on. A large, up front purchase is a great way to commit to a project! The trailer I used has a 1720 lb capacity. The (semi) finished camper weighs around 900 lb. I plan to bring that up to 1100 lb with the addition of a kitchen.
The trailer comes unassembled. When assembling the trailer, you can leave off the lights and the fenders. I ended up taking them off later because they got in the way of the build.
Much later on, I moved the trailer wheels back a half foot. There was not enough weight in the front for it to tow well.
Step 2: Floor
The floor is a single sheet of 4' x 8' pressure-treated plywood. I applied "Thompson's Water Seal - Waterproofing Wood Protector" to the underside of the plywood. This might have been unnecessary but I had the waterproofing stuff on hand. It was challenging to keep the plywood flat and square while it was being secured. Use all the clamps you have!
There were places on the trailer frame where bolt heads stuck up and prevented the plywood from laying flat. I marked these locations on the plywood and drilled shallow holes to make room for the bolt heads.
The plywood was secured to the trailer frame with carriage bolts and washers. The pressure-treated wood shrank as it dried so I tightened the bolts again after a few days.
I didn't bother to insulate the floor. The bedding material will cover the whole floor and provide adequate insulation.
Note: Using a 4' x 8' trailer allowed me to use single sheets of plywood throughout the project.
Step 3: Planning the Shape
Now I began to plan out the teardrop shape for the sides of the camper. This was done on the plywood sheet that would make up the outer wall on the door side of the camper.
The outer walls should extend past the floor so they can be bolted to the trailer frame. This also covers up the trailer frame and is more aesthetically pleasing. To plan for this, I drew a line parallel to the long edge of the plywood, 3 inches above the bottom edge. 3 inches is the distance from the bottom of the trailer frame to the top of the floor
I used string with a pencil tied at one end as a makeshift compass to plan the curves. I just experimented around to find a shape that was pleasing to the eye. I needed to find the specific measurements of this shape because I planned on cutting it out on a CNC. You can see the CNC programmed shape in the pictures. If you want to use a jigsaw, you simply need to draw the shape and cut it out.
I cut the door out with jigsaw so that I could use the cut-out to make the door later on. Thes
Note: At this point I accidentally started taking my pictures with a filter so the pictures look more Instagram than I intended.
Step 4: Framing
Next I framed the camper using 2x4s salvaged from construction site dumpsters. I planed the 2x4s down so they were all the same width. The 2x4 pieces were secured to the plywood using deck screws and wood glue.
The 2x4 along the bottom edge should be right above the line that marks where the floor will be.
I used a miter saw to cut angles in the 2x4s so they would follow the outline of the curve. The 2x4 pieces should overlap the line for the curve with at least 2"-3" remaining on the inside of the curve.
The 2x4s around the door, overlapped the plywood by at least 1".
I also framed where I would install a bulkhead wall to separate the cabin from the kitchen. I don't have the specific measurements I used, but I was winging it and so can you!
Step 5: Cut It Out
I cut out my camper shape with the frame pieces secured to the plywood. This was done with a ginormous CNC but there are alternate methods. The framing around the door was cut out separately. This was done so that the framing would overlap the plywood opening by 1", creating a door jamb.
I secured this side to the trailer, just to see how it would fit. I used a corner piece of plywood that had been cut off to secure the side at a right angle to the floor. I needed to take the side down again for the next step.
I used Bondo body filler to fill gaps in the door framing. Bondo was used liberally throughout this build. Any accidental gaps and holes can be filled with Bondo and sanded down. Pick up a gallon.
Step 6: Other Side
I took the side that had just been cut out on the CNC and laid the plywood piece for the new side on top of it. I squared the bottom edges of the two plywood pieces and clamped them together. Then, I used a router to cut the original curve in the new piece of plywood. I cut the window out using the CNC.
I framed this side much in the same way as the last. For the window, I had the framing overlap the opening by about 1/2". Then, using a router with a wide diameter bit bearing, I cut the framing so that there was a 1 cm overlap around the inside of the window opening. The plexiglass window will rest on this rim and be secured with caulk.
I honestly cannot remember why I didn't just cut this whole side out on the CNC as well. Hmmm.
Step 7: Securing the Sides
At the point I secured the walls to the side of the trailer. There were places on the side of the trailer where bolt heads stuck out and prevented the plywood from laying flat. I marked these places and driledl holes in the plywood. I covered these holes up later with trim. Each side is carriage bolted to the trailer in four places. You can using existing holes in the trailer or drill new ones.
I also drilled holes in the 2x4 frame pieces that rest on the floor. The carriage bolts in the floor get in the way.
Step 8: Insulation Celebration!
I used two layers of insulation. The first layer was old insulation I found in a construction dumpster. The second layer was duct insulation that was sitting around the shop. Staples were used to hold the insulation down.
There are no pictures of this process but I added pieces 2x4 framing where I would insert plexiglass tubes into the walls to create portals for light.
Step 9: Skinny
After insulating, I skinned the walls with a 5 mm sheet of interior plywood. I secured the whole sheet to the side and cut the shape out with a router Along outside curve, I secured the skin with screws because this area would be covered by the roof. Elsewhere, I used staples sparingly to secure the skin to the underlying framing. I later coated the skin with polyurethane.
Step 10: BULKHEAD!!
The bulkhead was made with 1/2" maple plywood. Pocket screws were used to secure the bulkhead to the wall. I have not saved the precise measurements but I will share the design considerations that I based my measurements on. The lower, vertical panel of the bulkhead would be the back of the countertop cabinets. I placed the bulkhead far enough back so that I would have adequate countertop space and adequate foot space in the cabin. The height of this bulkhead panel was the same height I wanted my counter top to come to. The upper cabinets can be set farther back without sacrificing foot space. So the horizontal bulkhead panel goes back about half a foot. The upper, vertical panel then extends to the top of the outside curve. This is where the hinge for the hatchback will go, so be sure to consider that when designing.
NOTE: I later had to remove the upper panel of the bulkhead to install the roof. It would be best to leave this piece unsecured.
Step 11: Roof Supports
These curved portions will provide support for the roof, along with the "ribs" that will be placed in between. To make these, I traced a portion of the outside curve onto a piece scrap plywood. I cut this curve on the bandsaw. Then, I clamped a wedge of wood so that its point made a right angle with the bandsaw blade and the tip of the wedge was 2" from the blade. I ran the same piece of plywood through the bandsaw again with the existing curve butting up against the point of the wedge. You should now have a curved piece 2" wide. Continue with this process to make supports for the outside curve up until the bulkhead.
Step 12: Ribs
The ribs are made from 1/2" plywood. They are spaced about 8" apart. Put a stronger rib (2x4) at the front base of the curve (not shown in pictures). This rib will need to hold in the inner roof while it is being curved. I framed a 12" by 12" square where my fan would be installed. Ribs are secured with wood glue and pocket screws.
Step 13: Roofing
I used a thin piece of scrap plywood for the inner roof. I tried to curve the plywood before installing it . I dampened the wood with wet towels and bent it around the outside of the roof. It bent very little so I'm not sure if this helped.
I pushed the plywood in through the back, where the upper portion of the bulkhead had been removed. This took a great deal of effort and an extra pair of hands. Once you have the plywood was somewhat in place, I screwed it down to prevent it from springing out. Then, starting from the front base and moving back, I secured the plywood to the ribs and curved supports. The plywood ended up splintering a little bit but not enough to make a difference.
Step 14: Fan Installation
For a fan, I bought a 1200 model Fantastic-Fan. This model is the cheapest and provides everything you should need. The other models have fairly useless additional features and cost a lot more. Installation was simple and explained in the product manual. I left the inside rim uninstalled until later.
Step 15: Modifications
I decided I needed more foot space so I modified the bulkhead. I don't really like the modification. The extra space I created is barely big enough for your feet.
Step 16: Cabin Interior
I covered the inside of the roof with fabric/carpet. This material was secured using contact cement. After cutting a hole in the fabric to expose the fan, I installed the inner rim piece of the fan.
To conceal the pocket screws on the bulkhead, I created a border around the bulkhead edges using scrap pieces of the skin plywood.
I made frames for the insides of the windows and doors using 1/2" scrap plywood. The inner borders of the frames were cut using the existing CNC programs. The outside border was drawn so that the frames would be 1.5" wide and cut with a jigsaw. The edges of the frames were curved with a router. Frame pieces were painted with white acrylic paint and secured with wood glue and staples.
There are no pictures of this process but, along the corners where the carpet meet the walls, I installed quarter rounds. These quarter rounds need to be PVC in order to bend significantly. A heat gun helped with the bending process. The quarter rounds were secured with staples.
Step 17: Door
Remember that door cut-out that was saved way back in step 3? Time to frame it. While inside the trailer, I held the door cutout in the opening for the door. Then, I marked where the overlapping 2x4 framing rested against the cut -out. Back at my workbench, I secured 2x4s along the inside of these lines. This was easily done with the straight lines. For the curves, I used the framing around the door opening to trace the curves onto the new frame pieces. I cut these curves out on the jigsaw and angled them using the miter saw.
The window framing was made so that about 1/2" of framing overlapped the inside of the window opening. Then, using a router with a wide diameter bit bearing, I cut the framing so that there was a 1 cm overlap around the inside of the window opening. The Plexiglas window will rest on this rim and be secured with caulk.
I insulated the door and then skinned it with a thin piece of scrap plywood. I had an old survey map I had salvaged from my school's geology department. I used contact cement to wallpaper the map to the door. Then I painted over the map with water-based Minwax Polycrylic protective finish. I applied this finish sparingly, with many layers to prevent the map from crinkling.
Securing the door to the trailer was one of the last things I did.
Step 18: Portal Holes
I found these cylindrical rods of Plexiglas. I thought it would be cool to insert them into the walls of the camper so that light could pass through them. Previously I had planned out the location of these holes along the walls and secured framing in these locations. Unfortunately, there are no picture of this process. The holes were to be located above the curve that divided the two colors of the camper. The holes would not extend past the cabin section. I drilled the holes using a hole saw bit with arbor. To keep the wood from splintering, I used a pilot hole and drilled from both sides of the wall.
Step 19: Painting and Trim
Painting was great because it took relatively little effort for major aesthetic improvement. To prepare the walls, I filled holes with Bondo and sanded. For paint, I used yellow and white Rust-Oleum Protective Enamel and mixed the paints to make a lighter yellow. I also Bondo'd and painted the exposed top edge of the hatchback. Its important that water not be able to penetrate into the walls through this exposed area. This insides of the portal holes were also painted
The trim is made from Brazilian pinewood flooring that had been saved from a previous house renovation. This wood is very durable and therefore suitable for exterior trim. However its is also very hard and therefore difficult to work with. The outside trim pieces are 2" wide, while the door and window trim pieces are 1" wide. To make the pieces, a floor board was held against the side of the camper where it would be located. The outside curve was traced onto the board then this curve was cut out on a bandsaw. The curve was smoothed out on a disc sander. To make the inside curve, 2" wide marks were made along the inside of the existing curve and connected. This curve was likewise cut out on the bandsaw and sanded. The trim pieces were secured with wood glue and staples. The inside edge of the outer trim pieces were routed. Both sides of the window/door trim pieces were routed. The finished trim was coated with teak oil.
Step 20: Hatch
The curved, vertical pieces of the hatchback frame were made from 3/4" pressure-treated plywood. The outside pieces are made with two layers of plywood while the middle piece is made from a single layer. The horizontal pieces are 2x4s.
I welded a steel frame to go around the edge of the hatchback. This was needed to seal the hatch around the edges, support the overhang of the roof, provide structural support, and provide a place at the bottom where the hatch could be locked to the trailer frame. To secure the steel to wood frame I pre-drilled holes in the steel and used deck screws. When I put the door in place I found that the steel had pulled the wood frame straight. I took the steel off, over bent it, and then re-secured it to the wood frame.
The hinge at the top is a 4' nickel, piano hinge.
Step 21: Electicity
The electricity runs off a single 12V car battery. The battery is stored in a box bolted to the tongue of the trailer. I ran wires to the fan, a light, and a charging station. I drilled holes in the ribs so the the wires could pass through.
The light is housed in an old motorcycle headlight I found. I replaced original bulb with LED's from a desk lamp. I also wired the LED light to the switch on the headlight. The housing for the light is made from a bicycle gear and a bent aluminum band. The light can pivot with this housing.
The charging station I found on Amazon (link below). It includes two USB ports, a cigarette lighter socket, and displays the voltage. It works well and was pretty cheap. I later made a bamboo face plate to cover the unattractive plastic housing of the charger.
Step 22: Roof
The roof is made from our family's old garage door panels. I insulated the roof before I began putting the panels on. This was done with spare duct insulation, which is made to soften noise. Rain falling on a steel roof can make a lot of noise. I used two layers of insulation and held the insulation down with staples.
It took quite a bit of cutting to remove all the unnecessary hardware from the garage door panels. It is important to keep some parts of the panels intact to provide support (see the note on the second photo). Caulk was applied to the outside edges of the roof before the panels were applied. The panels were secured with stainless steel screws. I had issues with the panels denting in places but overall I am happy with how the roof turned out.
On the hatch the panels were welded to the steel frame with caulk being used throughout.
I added panels starting in the front and moving back until the fan got in the way. Then I added panels in either direction from the top of the hatch. The panels ended up covering the hatch in back perfectly. On the top of the roof, I used PVC coated tin sheeting the cover the gap.
Step 23: A Prettier Roof
At this point the roof was ugly and was not water proof. I caulked between the panels and between the fan and the panels. Along the edges of the roof, the steel was ragged and exposed, plus the stainless steel screws were visible. I cut trim pieces from vinyl siding panels (see notes on first picture). I kept about a centimeter of the overhang. This would hopefully keep water from getting under the roof and conceal the edges. The trim pieces were secured along the edges with caulk.
I painted the roof with several coats of FLAT white Rust-Oleum Protective Enamel. Any glossy paint would have exposed the bulges and dents in the roof.
I covered the hatch hinge with PVC shower pan liner. The front edge was screwed to the roof, then the liner was folded back to covered the screws. The back edge was secured with caulk. I tried painting with white paint over the liner so that it would match the roof. The Rust-Oleum paint continues to flake off and I will have to find a better solution. I will probably try out some different paints.
This seems like a good place to mention that weather stripping was applied along the sides of the hatch (on the wood, not the metal). There were some large gaps so I used the thickest weather stripping I could find.
Step 24: Portal Frames
Each of the portal holes would have a frame around it, inside and out. On the outside I also made two extra frames for each side. For aesthetic reasons, I wanted the curve made by the frames to continue all the way to the rear of the camper, even if the holes did not.
The inside frames were cut from maple plywood. The outside frames were cut from the same Brazilian pine boards that had been used for the trim.
The frames were cut into the wood using the CNC. Then I used a table saw to cut behind the frames and release them from the wood. I sanded around the outside edges of the frames to smooth them.
Step 25: Installing Portal Frames
To install the portal frames, I first Inserted a piece of plexiglass tubing into the hole. Then, I slid the frames into place around the tubing. This made it certain that they were in the right location around the hole. Only wood glue was used to secure the frames. They splintered if staples were used.
Step 26: Installing the Plexiglas
The holes were somewhat irregular so I made the pieces of Plexiglas individually. I inserted the larger rod into the hole and marked where cuts should be made. I cut the piece out slightly larger than marked on a radial arm saw. I used a disc grinder to sand the piece to the correct length. After checking that the rod piece fit in place, I sanded the ends with wet, fine sandpaper. The rod was the set in place and sealed with a clear caulk around the edges. I used water-based caulk so that it could be wiped away with a wet towel. Paint thinner cracked the plastic.
I did not polish the ends of the Plexiglas tubes. The sanded ends allowed the tubes to act somewhat like a fiber optic cable and display a brighter light.
Step 27: More Door
I made frame pieces for the inside and outside of the window. I used two rectangular trim pieces to raise the bronze hinges level with the outside trim. I bought a door lock from Lowe's (link below) and painted it white. I installed thin weatherstripping after routing out a groove around the door jamb.
Step 28: Supa Fly Fenders
Before installing the fenders I moved the wheel axle farther back. The wheels needed to be moved because there wasn't enough weight on the hitch. To know how far back to move the wheels, I loaded up the back with about 200 lb of ballast (to represent a future kitchen). Then I moved the wheels to a couple of different locations. I found a place for the wheels where there would be about 100 lbs of tongue weight with the back fully loaded.
The process for moving the wheels is not well documented. Basically I used a metal cutting wheel to remove the U-channel that connected the trailer to the wheel axle. I moved it back 6", rewelded the U-channel, and bolted the U-channel to the frame with redrilled holes. I saw more than one way of moving the wheels back. However you want to do it. If you construct the hatch of lighter materials you might not have to do this at all.
The fenders came from an old VW bug and were cut shorter (the lights don't work). Part of the trim was cut away so that the fenders would lay flat against the side. The fenders were screwed, with stainless steel screws, to the sides of the camper. Coated aluminum covers the camper underneath the fenders. This area will be exposed to a lot of moisture and wear, so it was important to protect it. The aluminum was stuck to the side of the camper with caulk.
Step 29: Hatch Lock
I needed a way to lock the hatch down to the trailer frame. I cut the end off of a chain link and welded it to the trailer frame. Then I cut a hole in the hatch to allow the end of the loop to pass through. The hole was unattractively cut with a metal cutting disk, so a coated aluminum piece was used to cover the edges of the hole. Now a padlock can be used to secure the hatch.
Step 30: Ta-freakin-Da
My baby looks good!
It only took 30 steps
Now I need a job