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There are a several of different types of propane lockers available on line. They are designed primarily for boats and for larger bottles (tanks, cylinders) than what I wanted to use inside my van. Since space is at a premium inside a Metris, I elected to build my own using Lexan for an 11 pound bottle. Lexan is a very tough plastic that is easily worked with common wood working tools, ie a table saw and router. I've built a couple of underwater enclosures for cameras so this was pretty straight forward since I did not have to worry about an absolutely waterproof seal.

My locker is 13" long x 11" wide x 18 7/8" high, with length being the front to rear dimension as seen in my pics. The width is the dimension from side to side of the van. The lid is another 2" on top of the locker, so the overall height is right at 21".

The 3/8" Lexan is easily cut with a high tooth blade- I used a Freud 80 tooth blade since I already owned one. Use a fairly slow feed rate, but not too slow as you don't want to heat up the blade too much since that can lead to binding. The trickiest part in my design was getting accurate angles cut for the angled corner. I did a few test cuts in oak to ensure I had the correct angle on my table saw.

The Lexan is welded together using methylene chloride, which I bought at the same place that I purchased the Lexan (a local plastics store/fabricator). Your joints need to be fairly precise since you fit them together and apply the methylene chloride with a needle tipped dispenser bottle. Capillary action pulls the solvent into the joint. After a few minutes you can apply some pressure on the joint so you can do multiple welds without long delays. It takes a day or two for the welds to fully cure, depending on the temperature. The methylene chloride evaporates very readily so I kept mine in two sealed zip lock bags inside of a glass jar with a tight lid. I still had a slow loss of solvent over the course of a couple of weeks.

When I had the basic locker assembled, I filled it with water to check the welds. I had one corner that leaked slightly and it was easily sealed with another application of solvent.

The lid has a 1/8" rubber gasket and is held in place with two tensioning rubber latches. I built up the top of the lid into what looks like a tray, but its really for rigidity so that the seal is tight all the way around the lid. Even though 3/8" Lexan is quite rigid, there is enough flex in 13" that its wise to reinforce the lid for a good seal. I used 3M 5200 to glue the rubber gasket to the Lexan.

I used some Lexan scraps to form a ring on the bottom of the locker to hold the bottle in place laterally.

I have a vent in the bottom of the locker with a 1/2" inside diameter hose that goes through the left rear corner of the van and ends up on the bottom side of the bumper. Propane is heavier than air so any leak inside the locker will drain to the outside of the van. (A 1/2" hole in the bottom of the locker is another reason why you don't need an IP67 quality seal on the lid.) I had to cut through 3 layers of sheet metal to get the vent hose to the exterior of the van. I used 3M 5200 to glue a heavy piece of rubber to the outer layer of metal. The rubber seals the hole and keeps the hose from getting cut by the metal.

I have a vapor proof cable gland for the hose and another cable gland for 2 wires, which are for the shut off solenoids.

Inside the locker I have a pressure gauge, one solenoid that is closed by the CO/propane leak detector, and another solenoid for the on/off switch in the galley area. The galley on/off switch means that I don't have to access the locker to open and close the valve on bottle if I will be using propane regularly. The solenoids and pressure gauge are mounted onto a piece of Lexan that I can slide up and out of the locker. That means fewer holes in the locker and easier access to the solenoids and fittings.

I secured the locker in place in the rear corner on the driver side of the van. I used 1/4" stainless steel all thread to hold the bottle in place. The all thread goes through the floor and I have an 1/8" galvanized backing plate on the under side of the van. There is also a 1/4" bolt through the floor of the locker into a threaded insert. There are two 6 mm screws through the back wall of the locker into t-nuts in a 3/4" piece of plywood, which is secured to the van's walls.

Pictures

1- The hole for the vent hose.
2. The vent hose exiting the van.
3. The bottom backing plate.
4. The locker and lid without the solenoids.
5. The locker with the solenoids and pressure gauge.
6. Looking down at the bottom of the locker.
7. thru 9. The propane bottle and hold down in place.
10. The unfinished aft wall of my cabinet against the locker.
 

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Very nice job, thanks for posting all of the details and photos. My only question is concerning the solenoids- are they flammable gas rated?
 

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Discussion Starter #3
Very nice job, thanks for posting all of the details and photos. My only question is concerning the solenoids- are they flammable gas rated?
Thanks for the kind words Howvood. The instructions with each solenoid state they are for use with propane. One solenoid came with the MTI Safe-T-Alert CO/LPG detector. The other came with the the Sure Marine Propane Solenoid Control Switch.
 

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IMHO really nice job and well written / understood instruction how to. So far I am using small propane bottles for a single burner stove, I see in the future if I need more than just that, this is really good way to stay healthy in your van... what about outside placement?
 

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Discussion Starter #5
IMHO really nice job and well written / understood instruction how to. So far I am using small propane bottles for a single burner stove, I see in the future if I need more than just that, this is really good way to stay healthy in your van... what about outside placement?

Thanks Baron. I did look at options for an externally mounted tank. A lot of Class B motor homes have their propane under the vans. I found one upfitter putting a small tank underneath the Metris in the vicinity of the passenger side sliding door. (Sorry, I can't remember the name of the company doing that install.) I think the Metris is too low to do that safely, especially since getting stuck in snow is a concern for me. The long wheel base combined with the relatively low ground clearance makes high centering a real concern. Putting a tank on the rear bumper or a rear door would make it to much vulnerable in an accident IMO. Nor did I see anyone making mounts for that type of installation. So, as with most things in life, I had to settle on the least bad option, which was putting the tank inside the van and building a locker to minimize the hazard of having a cylinder of explosive gas in a confined space.
 

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It might be worth mentioning that for people without RansommRidges knowledge and skills, there is a commercial propane locker available. It comes as a complete Coast Guard approved system, and includes a 2.5 gallon tank, pressure guage, solenoid and solenoid switch. The vendor is Sure Marine. The size is similar: 14 by 14 by 18.5 high. The price is $686.
That is the one I installed in my Metris 6 months ago, and am pleased with the quality.
RansomRidge, did you decide to go with a gasoline heater, or are you going to use Propex now that you have the propane rank?
 

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Discussion Starter #7
Imants- No, I have a Webasto gasoline fired heater. The propane is just for my 2 burner stove so I won't have to refill it very often. I considered a smaller size (1 gallon), but this one was just 4 inches taller and offered almost double the capacity.
 

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Discussion Starter #9
Looks super cool. Wish I had your free time. I really live how you can see inside. It would make me feel safer for some odd reason.

For others without free time there are pricier options for 11lb tanks.

https://www.defender.com/product.jsp?id=3871440


Do you have your Webasto heater running?
No, I STILL don't have my Webasto running yet. But I'm getting much closer. Building my cabinet has taken much, much longer than expected. Once that is done, it won't take long to do the electrical and get the thermostat installed.
 

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Quality construction and very well thought out, your detailed forum post is just as impressive. Thanks for sharing
 

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Maybe I should go all electric!!!
 
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