Don’t know for sure how they pressure test tanks. Probably something more elaborate with a hydraulic pump and a bypass valve to set their test pressure. I just needed something cheap and crude so I dreamt this thing up based on stuff around our shop.
Success! (mostly)
Plumbed the AZ leader hose between the test cylinder and the tank - then began filling with water.
Attached some fittings and a gauge at the highest point to get all the air out.
With everything sealed up, I cranked the full 9" of piston into the cylinder. Either there was still some air in the system, or the tank actually expands with the pressure. 
Worked like a champ - I was able to get 300psi at full stroke. I wanted to test 400, but with a 235psi safety valve, it’s good to go.
Now I can get on with the installation.
awesome dude!
Thanks. That was a major hurdle.
I’m hitting a couple snags, but the next hurdle is getting the 1/0 out of the cab from my rear battery. That means taking out my 300# sub box.
I have about $400 in airline and fittings being delivered tomorrow. Not cheaping out now!
Where did you purchase the control box? I am needing one for my new setup, but cant find one like I want.
This one is made by Integra. It’s the nicest / cheapest enclosure I could find. It happened to be on Ebay for only 6 + 10.35 for shipping. If you want the model #, it’s at work since I downloaded their CAD drawing. LMK
Install update - I hole sawed my bed this weekend.
4 tonneau drains
2 for wires, 1 for tank drain, and 1 for outgoing airline.
I rust proofed the raw edges with POR-15. Good thing too, since it’s raining.
OMG thats it? Is this project finished?
No it’s not finished. Gonna have to wait til spring to get going again.
The big hold up is that I have to take out my sub enclosure to do the wiring.
That’s a major undertaking so I’m waiting for warmer temps & more light.
I can post pics of my pile-o-parts if interested.
O ok, spent 2 hours going thru this thread and it felt like the final chapter of the book was missing so I was like OMG, wheres the rest!? LOL
I brought the thing up to my living room for some plumbing progress.
Tank parts.
New check valves. New leader hoses will be hardlines.
Lousy tools cost more than the finished hardlines.
Made a stub tube to help with aligning the 1st bend and marking the 2nd bend.
All measuring and alignment is irrelevant when you capture a ferrule between two bends. /facepalm/
First try had to be scrapped. After this I made a detailed list of steps!
Before flare-
After flare-
I have never bent or flared tubes before so it was a learning experience. The 1st tube took about 3 hours. The rest took a half hour each.
Left pair, Square D pressure switch, AZ sending unit
Middle section with electrical box, safety valve, gauge, quick coupler
I am very happy with the result. The 4 tubes are pretty consistent.
I have everything modeled in 3D using Inventor. It’s great motivation to see the the finished product. Anyway the the real thing is starting to match the 3D model.
Very nice!
I think you went to a lot of trouble hooking up 4 compressors that’s going to draw as much current as 1 Oasis and won’t fill the tank as fast unless they output 2 CFM each from 100 to 200 PSI. The only advantage is if 1 of the compressors fail then you have 3 to back it up.
So its mid July, is this thing in your rig yet?
The tank is bolted in the truck. lol
Quoting myself:
^^This is exactly what I’m doing now. Old system is out. Been working on my new (big azz) box. I am without tunage so this is a priority right now. When I get the box & rear battery back in I can hook it up.
Awesome! Nice job. What’s your honk and refill times on that baby?
E2E? wheres the pics matey?
Wish I knew!
Sorry, truck is in the shop for a couple days. I can take a pic of the tank in her new home, but I don’t want to embarrass her cause she’s mostly naked. :o
i love naked pics 
he said it was a HER lmao