Why a foamie? Great question! My wife and I do not own a truck. We also refuse to buy one in today’s market. Therefore, we needed something light enough that a Honda Accord could tow it. We enjoy the cold, strange I know, so it needed to have a decent r-value for cold weather camping. I love the warmth wood can give to an interior, but not a huge fan of the rot factor. Also, foam is immensely easier to work and manipulate compared to wood. So, I set out to build what I think may be the first wood-free foamie? (please correct me if I am wrong)
I had no idea this forum existed until recently and now know that I am well over a decade late to this bandwagon. However, I did stumble upon a gentleman named George on Youtube under the channel Bug Out Trailers. I saw what he did with foam and wanted to build upon his idea, but up the ante just bit. I wanted to remove the wood floor frame and try a slightly different method with wall construction. I set out for some two inch XPS and quickly realized there is none in my area without jumping through some really inconvenient and oftentimes costly hoops. The good news is there is ample one inch XPS. So I then began to research how to laminate the two 4X8 sheets of XPS. I came across another channel on Youtube called The L Wood by Lucy. She built a small foamie towed by a Vespa. She utilized a product called foamfusion. She even dedicated a video to testing different adhesives on foam. I decided to give it a shot. I bought 12 1’’ sheets of XPS and ordered a 16oz bottle of foam fusion (mistake, definitely needed a gallon or more). The plan, because I was mildly skeptical that this laminated foam was not going to withstand highway speeds, was to build a rectangular prism to see if it could handle that ram air moving 70-75mph down the highway. The foam fusion claims that you only need just a very very light coat on each mating surface and 24 hours of cure time and you are all set. I was skeptical so I utilized probably a bit too much. The drying time was definitely closer to 48-72 hours before proper adhesion occurred. It is worth mentioning that this build was done this summer and took me only about a month working on the weekends and maybe an hour or so a day after/before work. Waiting on things to dry/cure was definitely the longest part. I glued up 10 of the 12 sheets because I knew the two end walls would be a bit different. Once these were cured I took a ryobi battery powered edge trim router and a ½’’ router bit that was 1” long and ripped a 1” deep and 1” from the edge of the foam to make what I call a puzzle piece. ( This will make a bit more sense when you see the pictures). I cut out the hole in the roof for the Maxxair fan and the holes for the windows in the two side walls. Lastly, I went ahead and layed the PMF on the interior portion of the walls.
Here is a shot of the floor on the saw horses and the ceiling/roof piece inverted on the ground. I hope you can see the routed out portion along the edges mentioned previously.
Here is a shot of the two side walls with the windows set in place to check for fitment prior to doing the PMF on the interior of these walls. Once the ceiling, floor, and two side walls were complete, I tackled the two end walls. One was in the front and the door was at the rear of the trailer. I opted to purchase new manufactured windows and door. Man was that expensive! The two windows, door, and Maxxair fan cost as much as the rest of the materials for the entire camper! Definitely room to save some money here, but I wasn’t quite prepared to tackle making my own windows and doors at this point. Certainly will be looking to give it the good college try on the next build though.
This was my first preliminary assembly to see just how good or poor of a job I was doing. Note that I had not cut out the windows or doors at this point. One thing I learned very quickly is that the sheets may measure square, but by some dark magic they are warped and bowed in a way that really confuses me. But the beauty of foam is that it is easily sandible.
I also want to point out how all the walls and pieces assemble like a puzzle. As I drive, the ram air pushed the front puzzle piece firmly into its grooves. Any load (little to none) on the roof will further seat the roof onto the side walls. And any crosswinds will seat the walls against the roof, floor, and two end walls. This is how I got away with no wood framing at all.
Next, it was time to permanently stick the pieces together. I took George's advice and went with gorilla glue construction adhesive and yet again grossly underestimated how many tubes I would need. I want to say I used nearly 10 tubes of the stuff sticking these walls in place. Do you know how stressful it is to have half a wall glued up just to run out of adhesive that has a cure time of 30 mins to have to run to Lowes and back before it dries? I was sweating to say the least. I was also not able to really hold the structure together very well while it cured because the ratchet strapping technique I thought was going to work was an epic fail. So, bamboo skewers and a ton of tape held this thing together while it cured.
This is after it was all glued up and cured. Note at this point I religiously used sacrificial pieces of foam under the floor to prevent from punctures or undue damage as well as the foam cut outs inside the camper to prevent from denting the flooring. (more on that later)
I flipped the camper upside down and applied PMF to the bottom of the camper first to test out these overlapping corners and because I wanted this seam under the sidewall PMF.
Then, the two side walls were done. (In hindsight I should have done the two end walls first) You can also see that I am smoothing any imperfections out with lightweight spackling. Yet another pro-tip from George.
Here is a shot of the inside once the camper was assembled. You can see where I added a bit more of the gorilla glue construction adhesive just for my own sanity and to fill any small gaps that were remaining. From there it was time to start getting some paint on this thing.
I read a lot on how people would water down their paint mix but the way I did my PMF (my first time and did what I thought was best) was a coat of titebond II and then laid the canvas down. I then did another coat of TBII to fully saturate the canvas. I did this for two reasons. One, it was cheaper than the paint by the gallon. Two, it is more waterproof (debatable I am sure) and it dries much harder than paint (basically more resilient). At this point I did 5 coats of 100% Glidden exterior water-based paint on the outside and 3 coats on the inside. Note the camper is upside down again in this photo. I did not want a huge white box so I got my wife to pick out some colors and quickly sketched out something that would be easy to tape off and paint and set off to work.
The base stripe.
The base stripe is un-taped with the windows installed.
Two more stripes were added and the door and fan just sitting in place for a bit of morale boost. Note the piece of ⅜” plywood next to the camper. I applied PMF to this and also painted it white. It served as my base so the 2x10’s on the utility trailer did not imprint on the foam. Which brings me to my next point. Remember how I mentioned that we didn’t have a truck but want one? Well a utility trailer would give us the ability to have a “truck bed” for hauling when we needed one and a camper that we can bolt down when we do not need to haul.
Here is the 5x8’ trailer we picked up. I got it because it had highway rated tires and I can easily remove the ramp (AKA 100lbs). The trailer dry weight is 550lbs, but once I removed the ramp it was about 450ish lbs. The towing capacity on our Honda Accord is a whopping 1,000lbs. So, we did not have much wiggle room.
Here it is on the trailer with a bit more paint and the Maxxair fan installed. I am sure by this point you are all wondering how I installed the Maxxair fan, windows, and door. The windows were the easiest. They came with clamp rings made for 2” thick walls. The fan and door were a bit more complex. I designed and 3D printed an interior clamp ring for the fan. The only issue is my 3D printer is not big enough to print something this big so I had to break it up into smaller prints, then glue these prints together. I printed them in a way that they would puzzle together and be held together by the through bolts that I used.
Here is the piece just loosely fitted together to make sure my measurements were halfway decent. Once glued up, it was obviously a bit more square. My interior radius was off a bit but I was able to make it work.
Here you can see the previous ring, now painted white with the through bolts. I used the same interior beauty ring the door came with as a clamp ring. This one did not turn out as good as I would have hoped. It was one of those “measure once and hope” type of days. So in my haste it is definitely my least proud portion of the build but works just fine. I used butyl tape and ran a bead of proflex around the outside to seal it off from the weather. I did not install the exterior “rain gutter” but have had no issue with water penetration. You can also see that I chose to do exterior routed wires for the fan and it works great. For lighting we just use the battery powered lantern you see here. The green box is a homebuilt solar generator that we use when boondocking. It runs the fan, brews the coffee (with an inverter of course), runs our 12v fridge, and charges our phones. I have built three different variations of these solar generators and use them a ton! However, you can also see that I have installed a shore power plug just next to the green box. Again, I just measured and designed a 3D printed “clamp ring” for the plug to go through. It allows me to mount the shore power plug and gives it a nice finished look. If I am hooked up to shore power I just plug in a power strip and a 12v power adapter to run the fan. Then, if we are off grid I simply disconnect the spade crimps on the fan wires and insert them into this cigarette socket plug to plug into my home built generator. I can provide more pictures for clarification if desired.
Here is a shot looking in from the door. The bed is a full size 5” thick trifold memory foam mattress that I cut down to fit widthwise inside the camper. It works great and certainly love the ability to fold it up out of the way for extra storage while on the road. You can also see the foam anti-fatigue mats on the floor. There are two layers of these on the floor. I experimented by putting all my pressure on one knee with the cutouts from the door. It left a substantial dent. So I added one foam square and repeated. A much smaller less noticeable dent occurred. So I tried a second layer and no dent. It is super cheap at harbor freight and adds yet another layer of rot free comfort. It also covers the bolts that hold the camper to the trailer. I used 9 bolts to secure the camper to the trailer. I 3D printed 8” diameter ¼” thick washers to spread out the surface tension on the foam as the bolt goes through. I also used a fender washer on top of that so it was not a straight bolt head on plastic. Underneath is a lock washer and a nylon locking nut for yet another redundant safety.
Here she is all painted up, spare tire installed. You can see the shore power plug here as well. Note that it does overhang very slightly. This was intentional because I did not want the front wall vibrating against the front rail.
Here we are about to set off on our maiden voyage. This was a four-day camping trip and naturally it poured the second two days. We were dry as could be and slept great! Shortly after that we set off on a 2,500 mile plus long trip. Let me tell you, this foamie has seen rain, snow, freezing, and scorching temperatures and tows like a dream. We even drove through hurricane Ian once it hit landfall. Still towed well and we were fortunate to get out of that unscathed. I had to keep reminding myself to look back to check every so often to see if it was still there. We averaged about 18-19MPG which is not terrible considering we were going through very mountainous terrain and that we were towing the least aerodynamic brick possible.
Here are a few photos from that trip as well. The only issues we experienced is that in heavy rain it looked as if the walls and roof had these little water bubbles in them. But as soon as the rain stopped and it warmed up, these quickly went away. However, the other issue we had was when sitting in the heat for long periods of time the side walls where the mountains are painted began to bubble up. I have to think these are heat bubbles or blisters. I took an infrared thermometer reading and the white walls reached about 95 degrees F, but the darkest of the mountains was a blistering 150 degrees! I do not know how to remedy these and am considering painting the whole thing white again to mitigate any further issues. I also noticed that the white paint definitely turned this off white hue. I am also considering sealing everything with a water based poly. Any thoughts or suggestions on this would be much appreciated. I can leave pictures for reference as well if that would help.
I still owe you all the exact weight of the camper. With the trailer being about 450lbs and my estimated weight of the camper being between 200-225lbs we are well under our towing capacity. Another added benefit of this design/build is that it fits between the wheel wheels of all full size trucks. With the tailgate down it is a lightweight, and relatively inexpensive project for a truck bed camper as well. I believe the total cost not including the trailer came out to just shy of $2,200. Again, the windows, door, and fan were $1,100 of that. So this could be done for much cheaper.
Well, I hope you got some use out of this and feel free to ask away any questions you may have. I am now certainly considering the possibilities of foam, and excited to see what creations we all continue to make out of this wonderful building medium.
