Greetings, Fellow Members of the Society of Garage Engineers!
I'm "DJ" Davis of San Antonio, TX. A couple of years back I contracted the insanity that I could build a camping trailer. I spent a year reading build logs, looking at pics on the internet, as well as reviewing as many YouTube videos and Instructables I could find on the subject. I started the build in late 2018 and declared the camper "operational" in August of this year (2019). The pictures above are the line drawing (adjusted during construction, of course) of the concept, a cardboard scale model, and the paint scheme concept for the exterior.
After a lot of research, I opted to build a "Foamie" hybrid covered with "poor man's fiberglass," or "PMF." I call it a hybrid because I used more wood for bracing than with most foamies. I tend to over-engineer projects, so I used wood where I thought it needed to be. Be that good or bad is yet to be seen. At least I have the peace of mind knowing something is braced well.
HF 4' x 8' trailer
2" and 1" extruded polystyrene (XPS) foam in 4' x 8' sheets
Hot-knife for cutting the foam
Titebond II and Gorilla glue
10 Ga canvas
LED lighting and 14 ga wire
120V to 12V inverter
4" deep stainless steel half-pan for sink
RO spigot for water dispensing
85# lift struts
Draw latches for hatch and tongue box
New-style hurricane hinge with rain channel
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Step 1: Trailer and Deck Base
The HF trailer was decked with 2" x 4"s and 1/2" exterior grade plywood. Like many, I went 6" over on each side to gain a 5' x 8' deck on which to build. The underside of the deck was painted with roofing tar. A four inch strip was left at the bottom edge to allow a place for the PMF on the sides to be glued to.. Wiring for the taillights was run before the top decking was nailed down.
Step 2: Side Layout
A lot of new house construction has been going on in my neighborhood, so I've had access to a lot of scrap lumber and other building materials for this project. The first pic above is a piece of electrical service drop wire that I used for a bendable French curve. That was used to transfer my scale dimensions to the materials for the build. I cut down pieces of scrap lumber into 1 1/2" x 2" widths for my bracing. Building a door frame in the "middle" of the side wall allowed me a taller profile. A lot of folks will notch their sidewalls, cover the outside with 1/8" Luane, then fill in with foam from the inside. I did the opposite - I applied the Luane directly to the edges, braced by gluing the bracing to the Luane, then filling in with foam before the PMF outer shell. With the door frame and no notching, I added about six inches to the center height. The camper doesn't seem as claustrophobic inside, but I almost made the camper too tall to get of of the garage after completion (a Leroy Jethro Gibbs moment, if you will). Pic 2 is the test fit of parts before affixing them to the deck. Pic 3 is the door frame installed with its top panel glued in. Pic 4, the front and rear side sections and pic 5, the use of bamboo skewers to hold parts in place as the glue dried.
Step 3: Galley Partition
Pic 1 - a combination of 1/2" plywood and 1" XPS to make the galley partition and counter. Pic 2 is with the wiring run, galley cabinets cut out, and a test fit of the cooler/stove placement. It was at this point I realized I was 2" too low with the counter and 2" too shallow for the front to back depth of the storage area under the counter. I had to adjust the plans for the stove placement and decided to build a cooler with the leftover foam to fit under the stove shelf. This galley design is modified from L Wms' concept; you can watch her video here:
Pic 3 is the view of the galley cabinets from inside the sleeping area. Pic 4 is the formica on the galley counter and the 1" blocks I glued into the 1" XPS cabinet wall edges to have something solid for the door hinge hardware.
Step 4: Construction of the Camper Front
My goal was a true teardrop profile, but I wanted storage space in what (IMHO) would've been wasted open-curved space in the sleeping area in the front. Pic 1 shows what I called the "tic-tac-toe" bracing made from 1" XPS. The window opening is 24" wide x 11" tall. Pic 2 is the view from inside before I cut out openings for the storage areas. Pic 3 is the cutouts - top center is 24" wide x 12" tall, the cutouts each side of the window are 12" wide by 11" tall. Wood blocks were also inserted/glued to the cabinet openings for hinge hardware attachment points as in the galley. All surfaces, inside and out, were covered with PMF. In the top left and right of the front wall are two oval-shaped areas that were left open. I refer to those as "grabs," a place to put gloves, a scarf, etc, and easily accessed from reaching in through the door. The exposed (not covered with PMF) side wall edges and the tic-tac-toe frame were covered by 1/8" Luane plywood to complete the inside of the front. I ran braces from side to side for structural integrity and to provide bracing for the window. Using a hotknife mounted to my tablesaw deck, I kerfed 1" XPS sections about 1/2" deep and 1 1/2" apart, then used the pieces to fill in between the bracing in two separate layers glued with Gorilla glue. Pic 4 is the front before the foam sections were glued down and pic 5 is the window installed and midway in the process of putting expanding foam in all the gaps. Cargo straps and 2 x 4s were used to keep the foam in place on the curved surfaces as the glue dried.
Step 5: Shelving at Rear and Front Storage
Pic 1 - rear shelves with bamboo accent rails.
Pic 2 - front cabinets after painting
Pic 3 - cabinet doors and bamboo accent rail installed
Pic 4 - a louvered blind set I made for the front window
Step 6: PMF, Tongue Box, and Painting
A foamie gets its structural integrity from the foam and bracing covered with canvas glued to the foam in overlapping sections then painted with exterior grade paint. I went with porch paint for its durability. The entire body is covered with PMF, inside and out. I left approximately 4" of exposed wood under the bottom edge of the deck to which I glued the canvas. After painting the entire exterior, to include the glued underside edge, I painted with roofing tar to the edge where the bottom meets the side. Any holes on the outside of the trailer drilled for wiring or screws/fasteners were filled with sealant or roofing tar. To the best of my knowledge this thing is watertight.
Pic 1 is the completion of the main body of the camper and all holes/uneven areas filled with expanding foam and sanded smooth
Pic 2 is the first side covered with PMF
Pic 3 - tongue box and PMF completed on main body
Pic 4 - painting completed; three coats of porch painted sanded between coats to smooth things out a bit
Step 7: Equipment
Multiple build logs mentioned that they regret not buying doors for their camper. One log stated that by the time you purchase hinges, windows, latch hardware, and drip trim, for a few dollars more you could have a complete door. My takeaway was the ones that complained of their homemade doors warping. I went with a company called Challenger Doors. They'll make your doors to your specs. Since I'm getting rather "chronologically enhanced," I wanted to be able to swing my legs into the camper easily. My doors are 40" tall x 36" wide. In other words, I "put a small camper on my doors." That was my main expense (~$750) on this build and I'd make them the same size again. It's a breeze getting in and out of the camper, plus loading/off-loading gear is very easy, too.
Pics 1 and 2 are the doors installed
For ventilation, I opted for the MaxxAir fan system. I like the dual support arms that raise/lower the cover and the cover is actually a screened cowl that will protect the opening from everything but a wind-driven rain directly from the rear. Like most fans it's reversible with multiple speeds. You can also run it with the cover completely down like a ceiling fan to circulate the air in the camper.
Pics 3 and 4 are the fan down and raised
Pic 5 is my icemaker filter between the exterior hose connection and the spigot on the counter. Next to it is the inverter system. Yes, I know...water and electricity should NOT be installed in such close proximity, but I made a shield around the filter and pex tubing from a plastic bucket and extended its height with the body of a plastic jug. The inverter mounting frame also has a plastic cover on the side of the filter and on top. Hopefully that will block water from any pex tubing leaks from spraying on the inverter.
Pic 6 is the newer style hurricane hinge with rain channel
Step 8: Hatch Construction
The hatch framing was made by gluing hardwood plywood together then cutting out ribs with a bandsaw. Cross braces were either solid Birch boards or hardwood plywood strips glued together to make composite beams. As with the front of the camper, 1/8" Luane was glued/nailed to the interior and exterior sides of the hatch. The interior of the hatch was filled with foams scraps cut to fit the spacing between the bracing (sorry...I forgot to get a pic of that step). Grooves were cut in the foam to run the wiring for the rear lights, pieces of angle iron were positioned where the lights would be mounted, the the exterior side covered with 1/8" Luane and PMF last. Vertical hatch weight force came out to 60 lbs and with an on-line calculator determined the lift strut placement of length/strength of strut required.
Step 9: Galley Layout
Pic 1 is with all the doors closed. Pic 2 is the kitchen "deployed." Cabinet doors inside the main body and the galley are 3/4" x 1 1/2" frames with a groove cut in the back edge. Pieces of scrap Luane were glued into the grooves to make a door panel. Bamboo placemats were cut to fit and glued in the recesses of the front of the door panels. I made a hinged flap over the papertowel holder to keep the wind from spooling off yards of towels on a breezy day. The holder was found at a yardsale. It also has a drawer under the towel holder; that became the silverware drawer. I incorporated the drawer/holder into the galley wall, covered it in the appropriate places with Luane scraps, and painted the Luane. If you watched L Wms' video, my sink set up is identical to hers except for the spigot.
Step 10: Artwork
The seven pics above are the various stages of painting the "theme" of the trailer. It's a nod to the movie "Crouching Tiger, Hidden Dragon." Hence the name in the last two pics - "Crouching Teardrop, Hidden Camper."
Step 11: Daybed/mattress Set-up
For extra padding and insulation, I added 1/2" foam gym matting on the floor. For the mattress, I purchased three pieces of medium density foam, two at 33" x 54" and one at 14" x 54". Pic 1 shows the three pieces set up in the daybed/couch configuration. At bedtime, the small piece goes at the foot/back of the sleeping area (pic 2) and the second big piece (pic 3) slides slides into the middle position to complete the sleeping surface. An unzipped sleeping bag goes on top of the "mattress" and either a light blanket or a second sleeping bag is used for cover. I might reverse the foam section order to prevent the "back of the daybed" absorbing foot odor.
Step 12: Spare Tire Storage
I didn't want to put a mounting rack for the spare tire on the tongue, so I modified the concept of a product I saw advertised for big-rig RVs. That system suspends the tire from side to side. I came up with a simple rack made from bent sections of 3/4" electrical conduit with flattened ends that would mount between trailer frame braces from front to back. The bends cradle the tire so there's no need for a threaded lug mount to hold it in place on the rack. Four 2" pieces of 1 1/2" angle iron were bolted in the pre-drilled holes of the frame. The flattened ends were bolted with 5/8" bolts, flat washers, and locknuts to the angle iron in the "rear" to act as the pivot point. The "front" flattened ends hold the tire up with a pin and a cotter-key on the right side and a lock on the left side for security. The small tire doesn't weigh much and it's easy to lift into place to secure with the pin and lock.
Pic 1 - the cradle - 24" long x 12" wide
Pic 2 - the cradle mounted
Pic 3 - the tire on the cradle (valve stem up)
Pic 4 - the cradle raised and locked into place
Pic 5 - a view from behind to show clearance of the cradle
Yes, I'll have to watch for steep driveways to keep the cradle from dragging, but I think that won't be an issue too much. To protect the tire in the cradle, I wrapped it in an industrial strength trash bag and duck tape. I figure that's an inexpensive way to protect the spare that can be replaced for about a dollar, if that.
Step 13: Side Tent
As you'll find out, having a teardrop means less space to move around in to get dressed. *****This is not a product endorsement, but I purchased the Ozark Trail two-room instant shower tent.***** After staking it down, I ran a piece of rope from one support pole around my roof vent to the opposite tent support pole. Sections of pool noodle protected the side of the trailer from abrasion by the tent poles. The set-up withstood 35 mph winds. Monday at noon (2019 Veterans Day) when a cold front blew through...violently...is when the side tent got its test. If I'd had the side guidelines staked out, too, it would not have wriggled at all in the wind. As positioned, the 35 mph wind shook it a bit, but no damage was incurred. The tent was (carefully) struck in the wind, folded up, and simply placed in the back of the car for the trip home. A quick set-up and sweep out in the garage later confirmed it survived. It was then refolded properly and placed back in the carrier bag for the next outing.
There's still a gap at the top of the tent where it meets the trailer's roofline, but a small tarp can cover that and take care of a light rain. For the cost, well worth it to have a place for the wife's lugable loo. The wife gave it her "squeal of approval" for not having to make a late-night walk to the restroom when needed.
Step 14: Maiden Voyage/shake-down Cruise
We ended up going to Ink's Lake State park for a one-night test trip Veterans Day weekend (2019). We were going to stay two nights, but the call for freezing rain on Monday night made up our minds for us. We had our electric blanket and a ceramic space heater ready for the freeze that night, but neither of us wanted to break camp in that kind of weather the next day.
The trailer tows like it isn't there. I did notice a bit of wagging around 64 mph, but I finally noted that occurred when someone was passing us. On a straight run with no vehicles around, the trailer towed straight as an arrow. Weight distribution came out with a 65 lbs tongue weight. Gas mileage was another story. Even with the rounded front, the fuel economy dropped about 20%.
I bought two 1000 lb capacity scissor jacks for leveling/stabilization in the rear and came across a third jack at a yard sale that I put under the tongue. The trailer was solid as a rock with the winds from that cold front hitting it.
Every part and feature built into the trailer has performed as envisioned. We look forward to our next trip.
I hope you enjoyed reading my tale of insanity. Please don't hesitate to ask for clarification if I wasn't clear enough on a construction point.