Luke's 6x12 Cargo Conversion

[Lrogers1843]

Hey all! I've been poking around here for a few weeks since the idea for a DIY camper popped into my head. I cycled through a few ideas, including a full foamie build, before settling on a 6x12 cargo trailer conversion.

Why build a camper at all? This project arises for me out of a lifestyle change - I'll be working as a wilderness guide for weeks at a time next year, and I have a home base with showers and kitchen where I can leave a camper, but without this I would just be living out of my car. Hence the urge for an upgrade! I will luckily have good lounge space to spend time in at this river base facility where I'll be parked, but also wanted to make a little private retreat room for myself out of the public fray. Plus, I'd love to make it as off-grid ready as possible for unforseen adventures, and because I am a solar enthusiast in general.

Unfortunately, I have almost no experience with the basic building skills that are needed here, besides a little bit of ugly shelf construction. Oh, and I don't have much time. I want to be road ready on March 1, just a bit over 8 weeks out. Please wish me luck and please chime in if you see any big mistakes looming!!

The trailer, purchased new in Douglas, Georgia

nose design sketch

rear design sketch


I'm still playing around with the final window count and placement - hoping to nail that down very shortly to order them. One hangup is also the wall thickness - I plan to land at about 1-3/4 total, with 1" metal wall studs inside the aluminum skin, adding 1/2" foam on top of that (in addition to between the studs), then then plywood interior that I'll just paint. Deliberating whether it's best to cut down a 2" wall thickness trim ring or just live with the small gap from 1-1/2 trim ring....

The next few days will focus on removing the existing plywood walls and forming a floor insulation and sealing plan - had intended to add furring strips and 1/2" foam + 1/2 ply on top of that, but recently saw a post building out the sandwich from below, which is attractive to save head height. Will keep exploring!

[Lrogers1843]

Started today with a weigh-in, including all stock interior plywood panels


Then I did an undercarriage inspection - the crossmembers are pretty deep and it seems like foam could be pretty sheltered between them, so I think I'll go with this approach for floor insulation.

The plan:
- Another waterproofing paint layer on the exposed plywood floor
- Loctite® PL® 300 Foamboard adhesive to attach foam
- More waterproofing paint over the installed foam

Any red flags with paint/adhesive compatibility here? I would have loved to epoxy the wood and glue the foam to that, but I'm not sure it makes sense without getting the factory paint off, which feels like overkill for my time constraints.

[Lrogers1843]

Today was spend mostly pulling out the interior plywood (not easy!) It is especially tricky around the side door trim, think I'll come back with a jigsaw to cut closer to those edges and get a little more room to work.

before

after


The next insulation challenge I've encountered is the doors - I think I'm too nervous and too rushed to take them apart and insulate inside. I'll need to think about how this would sit relative to the rest of the interior walls, but I'm tempted to simply glue foamboard on them and paint it white to match my walls. This feels especially appealing on the barn doors, which will be relatively low traffic and low visibility. Maybe with a PMF finish (I almost tried a foamie build, would be fun to do a bit of that technique)

[Lrogers1843]

Turning attention to weatherproofing while I have the interior exposed. I see two types of issues to address:

1) Floor gaps where the footprint makes turns off 90 degrees.I think I may attack this from below, using adhesive to attach a thin steel plate across the gap where the beams don't meet, then some spray foam or other filler on top.



2) Sloppy existing penetrations - all purpose silicon applied from outside? This one inside the wheel well is particularly disappointing.



(thank you, Diamond Cargo)

[Lrogers1843]

Minor progress: All of the vertical outside seams and especially the front failed the garden hose test, so I sealed them with clear silicon - looks ok from a distance and holding out water pretty well.

meanwhile, major appliances have trickled in, including inverter/charger in back corner. I also have solar panels and am just waiting for my 5kWh server-rack battery to ship before trying all that out.


I want to make major penetrations soon, starting with windows, which have now arrived. Plan is to cut steel studs and weld horizontal support angle iron to to attach the cut ends to neighbors, then trim the rest of the window hole out with dimensional lumber, I think.

plus, I thought out roof rack designs for the solar panels. The goal is to lay 3 of them inside an aluminum angle frame, all of which will pivot on a hinge to catch angled sunlight. The geometry didn't look good for my original plan of side-mounting the rack, so I think I'll switch to a roof-mount approach, although I hate to start cutting into the roof. Below is the rough sketch that convinced me to mount on top - approx weight of 3x250W solar panels and homemade aluminum frame is expected to be 125-150#.



The roof seems multilayered, which I didn't expect - soft plastic-y layer exposed inside:



and another layer on top, with aluminum panels in between? I'm a bit worried about potential flex or creasing of the top layer, and getting a good seal on it. Current plan is dicor self-leveling lap seal. Time for a deeper dive through the forum on roof openings in cargo trailers.