At the request of one of our fellow CPF members here is a description of my pressure pot. Now, I did not build this. I had a machine shop do it and due to a misunderstanding I paid dearly for it. Works great though and has been indispensable in dive light building.
The pot consists of an aluminum 80 tank that was decapitated with a band saw... It was then placed on a pretty huge lathe to face the end.
Oh, the tank was an old condemmed tank! A flange was built with 20+ holes, even though I asked for 6 1/4"-20... I got a bunch of metric thread! Part of the misunderstanding along with the aluminum flange which I did not ask for since I was goingwith 1" plexy! A 1/4" hole was threaded for a PSI gauge and valve with wuick connect. PSI gauge was free so that's why it's so big.
To use the pot:
1a. Fill the pot with water as much as possible
1b. Insert light or whatever to be tested
2. Put the flange on with the gasket.
3. Insert all bolts and tighten in a cross pattern until snug
4. Close the air inlet valve
5. Connect the compressor quick connect
6. Open the compressor valve, if closed
7. Slowly open the inlet valve to the pot
Note- after the pressure reaches the desired pressure or the maximum psi your compressor is capable of, close the valve. You will notice a slight drop depending on air temp and water temp. Don;t freak out and think there is a leak! A leak will usually chew up about 10-20 psi depending on the size of the object being tested. Usually a drop of no more than 4 PSI is OK.
Allow the object to sit in the pressurized pot for whatever time. I have gone from 2 hours to 2 days! Usually if it doesn't leak in 30minutes to 1 hour all is OK.
8. Release air pressure slowly
9. Remove cover and either be happy or extremely disappointed!!! If disappointed, take light apart, reassemble and repeat.
This is probably the most stressful time in light building for me. After you have spent hours putting a light together, it could be destroyed in seconds!
Some things I would have done differently:
1. Smaller gauge mounted on the lid to allow for full filling of water without any shooting out when depressurizing. Although I barely ever fill it all the way since this thing can probably handle 500 psi... The weak point is probably the gasket.
2. Mount the valve on the lid as well.
Oh, and the white stuff you see in the tank is the result of leaving water in it for months. The aluminum corrodes a bit.
The pot consists of an aluminum 80 tank that was decapitated with a band saw... It was then placed on a pretty huge lathe to face the end.
Oh, the tank was an old condemmed tank! A flange was built with 20+ holes, even though I asked for 6 1/4"-20... I got a bunch of metric thread! Part of the misunderstanding along with the aluminum flange which I did not ask for since I was goingwith 1" plexy! A 1/4" hole was threaded for a PSI gauge and valve with wuick connect. PSI gauge was free so that's why it's so big.
To use the pot:
1a. Fill the pot with water as much as possible
1b. Insert light or whatever to be tested
2. Put the flange on with the gasket.
3. Insert all bolts and tighten in a cross pattern until snug
4. Close the air inlet valve
5. Connect the compressor quick connect
6. Open the compressor valve, if closed
7. Slowly open the inlet valve to the pot
Note- after the pressure reaches the desired pressure or the maximum psi your compressor is capable of, close the valve. You will notice a slight drop depending on air temp and water temp. Don;t freak out and think there is a leak! A leak will usually chew up about 10-20 psi depending on the size of the object being tested. Usually a drop of no more than 4 PSI is OK.
Allow the object to sit in the pressurized pot for whatever time. I have gone from 2 hours to 2 days! Usually if it doesn't leak in 30minutes to 1 hour all is OK.
8. Release air pressure slowly
9. Remove cover and either be happy or extremely disappointed!!! If disappointed, take light apart, reassemble and repeat.
This is probably the most stressful time in light building for me. After you have spent hours putting a light together, it could be destroyed in seconds!
Some things I would have done differently:
1. Smaller gauge mounted on the lid to allow for full filling of water without any shooting out when depressurizing. Although I barely ever fill it all the way since this thing can probably handle 500 psi... The weak point is probably the gasket.
2. Mount the valve on the lid as well.
Oh, and the white stuff you see in the tank is the result of leaving water in it for months. The aluminum corrodes a bit.
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