[DC_Dave]

We had been contemplating turning our minivan into the occasional road trip micro class-b rv for two people. Overheating the engine, which necessitated the purchase of a replacement minivan left us with an extra minivan once the engine was replaced.

This provided the perfect opportunity to build the convertible camper using the old minivan. We recently spent nine nights in the completed SB42 between DC & Shediac, NB. The photo below is from Deer Island, NB.

The design criteria included a temporary conversion with minimal damage/changes to the underlying van. Ideally, it would only require the removal of the second-row seats and the front console.

Regarding the design of the bed, after a lot of consideration, we decided that a convertible bench/sectional design for the would be best. The idea was to be able to use the bed as a bench against the driver side sliding door in a way that formed a sectional with the third row bench seat.

A toilet for middle of the night pit-stops was a must.

Ventilation turned out to be the biggest challenge for us to solve, and another member posed what seems to be the best solution. We found a couple of tweaks to the ventilation solution, that I hope will help other people.

BTW: You may have noticed our windows look dark. We had the sides and back windows tinted with 40% VLT ceramic tint to help with heat and IR rejection - it makes a big difference!

Please feel free to weigh in and make suggestions to improve each of the features it will be covered in individual posts below. I'll post up the photos first, and descriptions later.

 

[DC_Dave]

First up, the bed. The idea was to build a platform that was an extension of the third-row bench cushion. The bench cushion would become either the head or foot of the bed. We wanted to be able to convert the bed into a short bench that set up against the driver-side sliding door and the third-row bench to create a mini sectional couch behind the front row seats.

The driver side panel is 27"x48 and the passenger side panel is 26x48.

Unfortunately, we haven't yet accomplished that. We went with a torsion boxes on and glued two sheets of quarter inch plywood to 2 in foam board insulation. Take a couple of tries to get the right adhesive for a strong lamination, and it turns out gorilla glue is perfect. A friend came up with the idea for the torsion box design is to provide lightweight members that are stiff enough to hold the weight of a person. In practice, the bed panels are plenty strong and probably way about 8 lb a piece. Leg plates were used and dowels were cut to fit to provide a flat and level bed platform. The driver side bed panel was cut to fit along the interior side of the van.


I'm 5'10 and barely fit when the front seat is most of the way forward. The panels only fit in place in bed mode with the front seats move most of the way forward. In drive mode the driver side bed panel slides up onto the rear bench seat, which is protected by a piece of indoor outdoor carpeting, and the passenger side bed panel slides over the driver side panel. The driver side panel is supported by four legs, one at each of the corners. The passenger side panel is supported on its driver side edge by 4 2 in metal brackets and interlock between the panels.


10-24 carriage bolts and nuts we used to hold the leg plates in place, and 5/16 carriage bolts and nuts were used to hold the 2-in brackets in place. The bed platform seems to work very well and sleep mode, and collapses down and drive mode nicely providing plenty of space in the back. Unfortunately, we haven't figured out how to turn it into a bench to create a section on the back of the vehicle. On this past trip there wasn't really much need for that, but we will continue to think about a better configuration for the bed. As you can see, plenty of storage under the bed panels that we took advantage of on our road trip.

 

[DC_Dave]

Next, the kitchen in the back (description & dimensions to come). You'll note that the bed and the kitchen shelf knocks down to fit in the back when not in use. The Massimo CX40 E-Kooler is a perfect fit! You do have to hold the carpet flap up to slide the cooler in place with the power cord plugged in, but other than that, it's wonderful. Draw very little power overnight.

Dimensions
Side panels
17x33, 15” at the top, taper down 24” from the bottom

Top panel 47x15

Center vertical 33x11

Shelf 14-¼ x 17”

¾” square stock

The shelf holding the Coleman stove is placed at a height allowing you to remove the Reliance Aqua-tainer from the lower right storage area. There's plenty of room behind the Aqua-tainer for dirty laundry, and we store wood pellets and propane in front of it.

The storage bins on top of the shelf are secured to the headrests with velcro to keep them from sliding and underway. We store the cast iron griddle and frisbee to the left of the shelving unit. To my surprise, the shelf does not appear to sway back and forth underway.

We wanted to be able to disassemble and assemble the shelf rapidly, so it is constructed using threaded inserts that accept one quarter by 20 threaded alan key screws. The only trick to using the threaded inserts is to plan for the removal of the screws using power tools when positioning the inserts. A drop of gorilla glue was applied to the inserts to keep them from backing out of the wood.

3/4" in stock is glued and wood screwed to the corners and shelf supports.

 

[DC_Dave]

First, huge tip of the hat to DKH for this idea. We were going to use the sunroof, but the rear quarter windows work SO much better.

Ventilation boards - Noctua NF-P14R 140mm fans (blowing in) & Noctua PWM controller. The outer surface of the boards are painted flat black and are invisible from the outside.

About 8w on max, we'd typically run them at 2w. Still looking for a solution to keep the mosquitoes out of the holes for the window actuatators and cracks around the boards. A 135mm hole saw cut the holes. Note the D-shaped weatherstripping around the windows that acts as a gutter to keep rain out. We only got to try it in the rain once, but it works!

 

[DC_Dave]

We use a Golabs 300R power station and rigged up a 12v auto backup so that the refrigerator is powered from the vehicle when it's running, and the power station when the vehicle is off.

Perhaps the most important aspect of a power station is most overlooked - the charging rate. The 300R will charge at 60 watts from a PD USB-C supply (sold separately). The power station couldn't handle the 12v startup current for the refrigerator and the continuous 6.5A of the iceless cooler at the same time. We started out by plugging the refrigerator into the 110v outlet on the power station and the iceless cooler into the 12v output on the auto-backup circuit. This used the power station as the continuous power supply for the refrigerator. Ultimately, we'll run the refrigerator from the power station's 12v output and the iceless cooler from the 110v outlet through a 12v adapter using, both using automatic switchover. The orange bottle in the picture is my project box for the automatic switchover.

By the way, the van's 110v outlets couldn't handle the startup current from the refrigerator, either. We ended up just powering the iceless cooler from one of the van's front 12v outputs without a backup and the refrigerator from the failover circuit on the power station. When the van was on, the refrigerator ran off the van's 12v rear outlet, and when the van was off, the refrigerator ran off the power station. This allowed the power station to charge at its maximum rate while the van was running (60W from the PD USB-C input).

Igloo 28qt iceless cooler
This thing is a power hog - 60 to 70 watts. It would suck the power station flat by itself (even without the ventilation fans or refrigerator) in 5 hours or less, assuming a full charge. There was no way to run it all night from a 300w power station that we could barely keep charged with the amount of time we spent outside the van. Besides that, it didn't cool so much as keep things from getting hot. The area under the cooler between the front seats gets hot because of the exhaust system under the floor. We'll have to install some sort of insulation or air gap to try to keep the bottom of the cooler from heating up.

The 7 gallon Aqua-Tainer was very handy with the simple siphon pump arrangement. Just get the water flowing, and hold the outlet below the bumper, and you have continuous flow. The valve in the cap was kept cracked so that water would flow without developing vacuum inside the container. This setup cost about $20.

The toilet is a 3.5 gal bucket with a bucket toilet seat (plastic liner and wood pellets). There's enough room to use the bucket when the door is closed and the bed in place. The handles on the ceiling and door help. We replaced the rear light bulbs with red LED for night-time use without disturbing the other person or hurting night vision.

 

[bencahill]

Thanks for posting the pics and descriptions! I love the cooler that fits between the front seats. We have a 40-quart Coleman and found that we can fit it between the first and second rows with the second row slid all the way back, but your smaller one up front would be much more easily accessible. We recently slept 5 in our 2009 LE. I will be posting about that soon...

How long does it take you to set up the kitchen and bed platforms?

Also, what do you use as a mattress for the bed?

 

[DC_Dave]

Thanks, we hope they were helpful!

We started calling the Igloo 28 iceless cooler the "un-hotter." It's capable of cooling up to 36F below ambient - which is cool enough. Ours never got that cool because the metal under the console/cooler is HOT. If you do place a cooler between the front seats, you'll want to install some sort of spacer between the floor and the cooler. We're planning to bolt 3/4" square wood stock in place of the console base plate.

The bed takes less than 5 minutes from start - just screw 4 legs into the driver side panel, 2 legs into the passenger side, and set them in place.

Setting up the kitchen cabinet probably takes 10-15 minutes to thread the alan head button screws in place.

We're campers/backpackers, so we use air mattresses.

 

[floridanative]

Looks great! Yeah, those Peltier thermoelectric coolers just aren't worth it unless you are literally only using them while driving. We have a cheap 12v compressor fridge and I LOVE it, one of the best things about our campervan.

-Mike

 

[DC_Dave]

Yes, that's our experience as well.

We're hopeful the igloo 28 will work for us on road trips once the bottom is isolated from the heat and and it's on a automatic switchover circult.

Looks great! Yeah, those Peltier thermoelectric coolers just aren't worth it unless you are literally only using them while driving. We have a cheap 12v compressor fridge and I LOVE it, one of the best things about our campervan.

-Mike

 

[bencahill]

We started calling the Igloo 28 iceless cooler the "un-hotter." It's capable of cooling up to 36F below ambient - which is cool enough. Ours never got that cool because the metal under the console/cooler is HOT. If you do place a cooler between the front seats, you'll want to install some sort of spacer between the floor and the cooler. We're planning to bolt 3/4" square wood stock in place of the console base plate.

Ah yes, I have also noticed how hot it gets there.

Looks great! Yeah, those Peltier thermoelectric coolers just aren't worth it unless you are literally only using them while driving. We have a cheap 12v compressor fridge and I LOVE it, one of the best things about our campervan.

What 12v compressor fridge do you have? When I was researching them a few years ago, I didn't remember "cheap" being an option. I think they started around $500-$600. Looking on Amazon now, I'm seeing them for $200-$300, which is not bad. We got a Coleman thermoelectric for ~$80 and it has worked great for our needs (we only use it in A/C areas).

 

[DC_Dave]

We are using the Massimo E-Kooler CX40 (~$300), which is a perfect fit for the rear well on both the Gen 2 and Gen 3. You can see it in the kitchen pictures above.

 

[floridanative]

Ah yes, I have also noticed how hot it gets there.



What 12v compressor fridge do you have? When I was researching them a few years ago, I didn't remember "cheap" being an option. I think they started around $500-$600. Looking on Amazon now, I'm seeing them for $200-$300, which is not bad. We got a Coleman thermoelectric for ~$80 and it has worked great for our needs (we only use it in A/C areas).

It looks like they don’t sell it anymore, but it is a Costway 32 quart. We paid around $200 for it on a Black Friday sale almost two years ago. But that was on sale and prices of EVERYTHING are higher now because of you know, reasons. It’s similar to, but clearly different from, the Alpicool C30.

It has been running non-stop since COVID started. It was an overflow fridge for when the teenagers were home, it was a freezer when we took our oldest to his apartment with a bunch of frozen food so he could quarantine, it’s our camping fridge, and it’s our fridge for drinks with the kids out of the house.

-Mike

 

[bencahill]

Thanks guys! Good info. Mike, it sounds like you have definitely got your money's worth out of that one.