Part III: Capper and Tent Design
Goal: Being able to stand up inside the living space was one of the
primary build constraints that we had from the start. The problem is that there are dozens of ways to do this, and all of them are quite expensive. Not to mention, if you screw up the functionality of your primary living space, life on the road is a lot less fun!
Build Time: Approx. 40hrs
Cost: Approx. $4050 (Tent $3300, Capper $500, Steel and Supplies $250)
Inspiration:
This is where Overland Expo and Expedition Portal becomes a smidge overwhelming… there are so many options on living spaces, rooftop tents and the like. You could go with a Fourwheel Camper but where’s the fun in not designing your own (if you’re a nerd like me). Rooftop tents are cool until you’re camping in rain/mud and end up dragging it all into your bedroom.
Lindsay also wanted the ability to be moderately incognito and have a quick setup/teardown process. I didn’t want to tow a trailer, as it just becomes a liability as soon as you need to back out of somewhere dicey.
Our first thought was a Tacoma Habitat, as it gives you standing room in the bed, a decent sized bed to sleep in, and the added benefit of an overhang/awning behind the truck when fully set up. Unfortunately, the $9,000 base price and $12,000 end price with insulation for winter camping, shipping, etc. put the Habitat out of our price range. If we had an extra $10,000 in the build budget, I’m pretty sure we would have one on the truck right now.
Fortunately, I was introduced to Alu-Cab and OK4WD on my last trip to Expo East in 2017. Alu-Cab’s Khaya insert system is the Rolls-Royce of Tacoma inserts (as in it’s luxurious, heavy, and expensive…).
The Khaya tent has everything we were looking for:
• Quick setup
• Standing room
• Onboard water, solar, and storage
• Relatively compact
If you think the Habitat was out of our price range, then the Khaya was going to require our firstborn child.
BUT – why couldn’t we build our own?!
Concept:
If we couldn’t buy something off the shelf, we were going to build our own prototype. The idea was to take a rooftop tent off the shelf and a truck capper, cut a hole in the bottom of the tent and the top of the capper, stick them together and figure out a way to cover the whole for sleeping. Easy Peasy.
The Alu-Cab Expedition III tent made the ideal sleeping space, specifically because you could cut a hole in the aluminum shell. A lighter fiberglass tent would lose a lot of structural integrity as soon as you cut into it, so we went with a high-end rooftop tent. Then we found an old electrician’s contractor-style truck capper that came off a Chevy Colorado with a 6’ bed. It was a perfect fit for the Taco. The gullwing side doors, french doors in the back, and extra height were all “happy little accidents” that we are utterly grateful for. For $500 on Craigslist, this was the best deal of the entire build.
Structural Concerns:
Even though it was an “industrial” capper, the rated roof capacity for the 1×1 aluminum square tubing structure was only 300lbs. Not only would we be over twice that with the tent and occupants, but we were also cutting a hole in the middle of it. Reinforcing the capper and getting the force load of rooftop occupants down to the frame was the first concern.
We also had the issue of a large hole in our sleeping platform that needed to be easily covered when it’s time for sleep, and yet still has enough structural integrity that a 230lbs dude doesn’t fall through. Alu-Cab solves this with the Khaya by having their entire sleeping platform lift with hydraulic pistons, and when it is lowered, the platform is braced down onto the outer frame of the base unit. Since contractor toppers are not really designed for rooftop tents, it was a little more complicated than just copying their design.
Final Design:
We decided to offset the roof hole so that it fits into the “galley line.” Basically, one side of the bed would be water, kitchen, and storage, and the other side would be a walking/sitting/open area. The gas tank is on the driver’s side, and the stock inverter is on the passenger side. For convenience and weight distribution, the kitchen and storage would be on the passenger side. This meant that the hole in the roof would be offset a bit to the driver’s side so we could stand up in the “galley.”
The hole needed to be wide enough for Clay to stand up in, but small enough that we could still get two people and a dog into the living compartment with the access hole open. We planned to cut it about 20” x36” and preserve as much factory bracing/structure in the tent as possible.
The capper would be mounted to the truck with three 2” x2” pieces of steel angle iron that would run the full length of the bed and the headboard. We planned to reuse the mounting bolts for the sliding cargo system to tie the angle iron to the truck, as those are structural pieces. We bought steel 1” x3” tubing to tie the exterior of the tent to the top of the capper. That structural steel was bolted to four 1/8” wall 1” x1” braces which ran down to the angle iron bolted to the top of the bed. If everything went right, the weight from the tent would go from the lengthwise steel tubing to the four braces and eventually down to the bed and the aluminum structure of capper would be secondary.
Finally, a hinging “drawbridge” (designed on the fly) would cover the hole in the tent. In theory, it would brace down to the steel tubing running the length of the tent and hinge on the lateral side. Open the flap, climb up top, close the flap, go to sleep!
Note: If you care about the details of the design that I brush over here, let me know, and I can send you a bunch of photos. I didn’t want to ruin a 1,000-word article with going into monotonous details about attaching points, force loads, and the like.
This is the first of a 2-part post detailing the construction of our living space, I'll type up p2 in a few days!