Modular cargo conversion

been right at year since my last post, and here is a bit of an update...

the modular design has proven to be perfect for us and how we do things. super easy to take out or add components depending on what our trip is going to be. for anyone doing their own build, i'll show some changes i made and explain why. this might be helpful to someone and save them some time and money...thats what this forum is all about, right?

originally i had the kitchen component as a cabinet with a built in sink, built in 15 gal fresh water tank with 12v sureflow pump and sliding doors where i could access the interior without requiring space to open doors outward. the pump, 12v outlets and lights are wired so that the kitchen module has an extension cord that plugs into the battery box. easy to just unplug and remove the whole unit without undoing wiring.

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we did a lot of trips with this set up and it was pretty good. had a few things we didnt like, but overall was good. the 15 gallon water tank i bought was crap and had a leak at one of the seams on the bottom that i didnt notice until i had mold and rot where the water collected between the vinyl underlayment and the wooden bottom. it was a very slow leak, so it went unnoticed for quite a while. i ended up scrapping the entire thing and just rebuilding a totally new and different set up...

first, i got rid of the built in sink. we rarely use it and it turns into a catch-all where various items seem to collect in there no matter what. also, being self contained, i had a 5 gallon tote in there dedicated to holding the drain water. that took up a lot of space and could get sort of nasty if not sanitized constantly. i also got rid of the 15 gallon dedicated water tank. the tank was ok, but took up a lot of space and i had it plumbed so that it could get filled in place by city water (if hooked up at a campsite) but for boondocking, which we mainly do, i had to fill the tank by going out and filling a 5 gallon tote and then pour it into the tank. kind of messy at times and just plain redundant since i still needed 5 gallon totes to get and transport water. instead of the built in sink, we went with a simple plastic tote like the ones they use to bus tables in restaurants. works great and we can take it out and use it as needed and when not needed, i now have that extra counterspace available for other uses. instead of the dedicated water tank, i just built the cabinet to fit the 5 gallon secpter water totes. i still use the 12v sureflow pump, but now i have 3 five gallon totes on the right side of the cabinet with a hose to just drop in thru the spout. when one tote is empty, i swap the hose and then go refill the empty tote next time we are out and about. i have a portable hot water heater plumbed into the cabinet and since we no longer have a faucet, i just use the shower head to fill the tote for doing dishes. i have a 2.5 gallon tote on the counter for cooking and drinking water. easy to refill and easy to store anywhere while were driving and then just set back up on the counter when we make camp.
and instead of having the sliding doors like the old style medicine cabinet, i just went and made pull out drawers with latching slides. i didnt need to worry about having space right there, so a pull out drawer is fine and actually easy to deal with since i can pull out the drawer i need and easily access it rather than slide a door and then try to reach in and find something.

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i have also plumbed in propane with a bulkhead cut off valve and a QD so i can hook up my shower or disconnect it and plug in my camp stove. with the shut off valve on the inside, i can shut off the propane without having to go outside and close the valve on the tank. i dont like trusting the one valve on the stove or heater with the line pressured up and us sleeping in there.

i also redid our solar and upped the battery to 280ah lifepo4 and a 60a controller and a 3kw pure sine wave inverter. too lazy to do pics of that right now, but it is an improvement over what i had and i am currently working on a way to use a regular window a/c unit inside the trailer. i basically will build a box for the unit to go in and then divide the box where the fresh air comes in one side and the hot exhaust goes outside without the unit sticking out past the wall. its going to work like the portable a'c units that have the two hoses...one for fresh air intake and the other to exhaust. its a lot more efficient that the units with just the one hose. if anyone is interested in knowing how to use a window a/c unit inside a trailer without having it stick out, stay tuned and i'll post my setup after i have it dialed in...

another thing that got changed was our food storage. right after my last post on here, i ended getting a couple freeze dryers and freeze drying pretty much everything. there is a thread on here with more details. that helped a lot with dealing with refridgerating food and making meals very quick and easy out on trips.
also working on a false floor cavity for when going thru customs and border crossings.
 
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Like your idea for the ac unit, looking forward to seeing photos when done. Remember to let the wife out from under the floor after your cross the border, or at least drill some air holes......
 
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got back a couple weeks ago from boondocking in the gila national forest then outside of Sedona and then finished up with page az and then boondocking outside of Zion. we were on quite a few fairly rough roads getting to boondocking sites and my all steel cargo trailer did great. brother-in-law has a factory camp trailer from forest River and like every factory made camper I've seen, the rough roads shook it apart. I had a forest River "off road" rated camp trailer prior to my build and the crappy workmanship was part of the reason for me to do one myself. building the interior out using screws and marine grade adhesive is far superior than the factory construction using just staples. I bounced that trailer all over and had zero issues.

so, for anyone like us that wants a very robust camp trailer that can be modified easily and repaired easily...then I highly recommend getting a cargo trailer and do your own build.

after using the trailer for over 2 yrs now, I figured it would be a good idea to insulate it now. I am going to remove everything and then insulate using xps insulation board bonded to a thin plywood and then reinstall my components. another mod I'm working on is to use the drop deck rear door as an actual deck with a screen across the opening so we can have a nice night view during good weather. while at gila, the temp was in the 50s and the night sky was absolutely amazing being out in the middle of nowhere with zero light pollution. we decided that we need to have the back open as much as possible....really adds to the outdoor experience.

still designing my setup for using a window a/c unit where it is not permanent and will not be protruding from the trailer wall. I have a roof mount domestic a/c, but I really don't want to use it. for one, the cargo trailer doesn't look like a camp trailer and having the a/c unit mounted on top would give it away as a camp trailer. also, I went with the extra height cargo trailer, and adding the a/c on top would mess with my clearance height. I also like using a small window unit that I can get at home Depot or Lowe's and then if I ever have a problem, I can just stop at any depot or Lowe's and get a replacement quick and easy and relatively cheap. my 13000 BTU domestic was $2000 and my window unit was just under $200.

i'll be adding a few pics as I go and hopefully what I'm doing will be of help to someone doing the same...
 
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found a good electric hot water heater. Vevor makes a nice 4 gal water heater that runs off 110v and was $94 on their black Friday sale. so I revamped the shower and added the side wall so that I could plumb the valve and shower head and have the electric heater close by.
prior, I just had the shower pan with a shower curtain around it and using the hosed shower head with the propane instant water heater. worked well, but time for an upgrade. as seen in the background, I still have the propane instant water heater on the wall for back up or when we don't have electric.

this is a nice set up because I can use my 12v pump to supply the electric water heater and set the thermostat at the right temp where I don't have to mix in cold water. I can run straight off the heater without needing to plumb in the cold side. saves work and fittings and is quick and easy to do.


I could use this tent camping by running it off of a small 2kw generator and use a 12vdc pump and a Jerry can of water to get a nice hot shower easily. figured I'd share for anyone who is building their own camper...
 
ok, here is some cold weather data for anyone doing or thinking about doing a cargo trailer conversion...

we just got back from 10 days in Missouri where the temps dropped down to 24 degrees and snowed. the trailer is just metal walls with no insulation and just a thin carpet on the floor. yeah, it was cold in there when I was pulling it and the dogs water dish froze over. once we stopped, it heated up pretty well. its a 16' trailer, so it takes a little while to get warm, but a buddy heater will heat things up pretty quick and the diesel heater we have (5kw off amazon) does extremely well getting up to temp and holding the temp. we were at campgrounds since Missouri doesn't really have any dispersed camping so that means we had electricity. I used 2 milkhouse heaters (1500w each) and after a few hours, ended up having to throttle back on one of them. there is a little condensate that accumulates on walls and the ceiling, but nothing too bad. a while back I had attached canvas tarps to the wall with magnets, but I'd just as soon leave the walls open. I was thinking about insulating the trailer, but I slept really good in there even with snow and 24 degrees temps outside. the diesel heater works best, but does make noise and has the exhaust to deal with versus the ease of electric heaters when power is available.

if I lived in the thing full time or for even long periods of time, I would probably insulate...but for 2-3 weeks at a time, I think the plain metal is fine. 3kw of heat is plenty good and can be dialed back to 1.5-2 kw to keep a comfortable temp thru the night
 
ok, here is some cold weather data for anyone doing or thinking about doing a cargo trailer conversion...

we just got back from 10 days in Missouri where the temps dropped down to 24 degrees and snowed. the trailer is just metal walls with no insulation and just a thin carpet on the floor. yeah, it was cold in there when I was pulling it and the dogs water dish froze over. once we stopped, it heated up pretty well. its a 16' trailer, so it takes a little while to get warm, but a buddy heater will heat things up pretty quick and the diesel heater we have (5kw off amazon) does extremely well getting up to temp and holding the temp. we were at campgrounds since Missouri doesn't really have any dispersed camping so that means we had electricity. I used 2 milkhouse heaters (1500w each) and after a few hours, ended up having to throttle back on one of them. there is a little condensate that accumulates on walls and the ceiling, but nothing too bad. a while back I had attached canvas tarps to the wall with magnets, but I'd just as soon leave the walls open. I was thinking about insulating the trailer, but I slept really good in there even with snow and 24 degrees temps outside. the diesel heater works best, but does make noise and has the exhaust to deal with versus the ease of electric heaters when power is available.

if I lived in the thing full time or for even long periods of time, I would probably insulate...but for 2-3 weeks at a time, I think the plain metal is fine. 3kw of heat is plenty good and can be dialed back to 1.5-2 kw to keep a comfortable temp thru the night

Your comment “3kw or heat……” is funny to me as I severely overestimated my need for heat in the back of my truck… 8kw barely has to run to keep an even temp so it is overkill!!! But for $100 oh well!
We got rained on and my buddys shirt was soaked and it dried it within minutes… so there’s that…
 

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8kw barely has to run to keep an even temp so it is overkill!!!
nice!
you're ex-military..."overkill" is SOP. in the navy, if a 1/2" rope is rated for 700#, then we'd use a 3/4" rope to lift 200#
if I saw an 8kw heater for $100 I'd get it for "just in case". my wife is always commenting on how I overbuild everything, so yeah, you did the right thing on that heater
looks like you have a good set-up
 
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not to make this overly complex, but these are GREAT posts and really could be an important thing to address. i have the cam action lever lock on my side door as well as the lockable RV type door lock. if i remove the bar lock, the door wont seal right. i closed the door the other night and didnt use the cam bar lock and the door was still secured with the RV lock, BUT the door can only be shut tight by the bar lock. it rained and a lot of water went in because the door was secure, but not tight against the weather seal.

View attachment 237117 i considered opening the bar lock and then drilling a hole thru the hinge where i could pin it in the open position for the night while im in there. i like the idea of being able to unbolt from the inside, but this appears to be a self tapping fastener? there is not a nut on the inside to get to.
i dont know...after the wife mentioned that, i do feel that i need to address this. even if i end up doing an egress window later, i still need a fix for the interim.

it definitely would suck to get locked in the trailer and even WAY worse would to be locked in there with my redheaded wife hollering "I TOLD YOU SO" for endless hours until help arrived. i dont think i could chew thru metal, but....
I've seen people swap out the cargo door for an RV style door.
 
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I've seen people swap out the cargo door for an RV style door.
yeah, that is a VERY good idea....
the wife had read an article a while back where a couple were sleeping in their converted cargo trailer with the cargo door and bar lock. someone locked the door with them in it and disconnected the trailer and stole their vehicle and they were trapped in there until help came. also, the cargo door only seals tight with the bar lock engaged and you cant do that from the inside, so if it rains, it will leak in. also nice to swap to an RV door to have the screen door with the main door open.

don't have the time for a swap yet, so I just installed a window in the door and carry a battery grinder with a cut-off wheel inside to give the wife piece of mind that we wont get locked in.
 
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while I'm on it...I also have some electrical data to share...

since I'm only wiring for 30amp service, I went with a smaller panel that has the DIN rail. its not any cheaper really, but is smaller and so I went with it. as seen below, the breakers are smaller and attach to the DIN rail in the middle.

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the whole premise of my build out in a cargo trailer is that its stronger and way better built than a factory trailer and EVERY part can be found in any decent hardware store. that way, if we're out in the boonies and have a failure, I can easily make repairs in the field and at worst, have to drive a few miles to a Lowe's or ace hardware to get parts. had an issue with electric on our last trip and luckily, I was able to hit a Lowe's and get what I need. a lot of RVs have special stuff that isn't always easy to find replacements for. my breaker box was fine, but I realized that the DIN rail box and breakers are not that common, especially if I'm limited to small hardware stores in little towns. I just tore it out today and went with a regular 125 amp panel from home depot that uses the same breakers found everywhere. I mentioned earlier in my build post about getting the DIN rail box and how much I liked it. I do like it and I doubt it would ever fail...BUT if it did and I'm out and about in the boonies somewhere...its going to be a LOT easier finding regular breakers. its still wired up the same and I'm feeding it with 10awg wire from the shore power plug, so nothing has changed other than going with a standard box and breakers. when doing your own wiring, definitely check your voltage drop...especially with 12dc. I ran a circuit off my 280ah battery using around 20' of 12awg wire and my voltage drop went to 10.8-11.3 volts and my 12v fridge went into error mode. need to step up to 10 awg wire for that.
just stuff to think about if you're wiring your own stuff...

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with 30 amp service, I'm using one 20 amp breaker that goes to the heater/induction burner (not both at the same time, too much amp draw) and 15 amp breakers for everything else and I go with 12 awg wire even on a 15 amp breaker just to make sure the breaker is the weak link.
 
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