Solar Cooler in a Can

Step 7 Prepare the Propane Tank

DO NOT PERFORM THIS STEP WITHOUT ADULT SUPERVISION! This step is NOT safe and I am not responsible if you blow yourself up. Proceed at your own risk.

Now, the propane tank must be completely empty. Make sure you release all of the propane from the tank by attaching a blowtorch attachment,  opening the valve, igniting any gas, and leaving the torch open after the flame goes out. Then carefully drill a small hole in the top dome of the tank. Next, use a hacksaw to cut the top off of the tank, making sure you rotate the tank as you go. There are two valves that protrude below the top of the tank and they make cutting more difficult.

Now sand down all of the sharp edges you just made and give the whole thing a nice new coat of paint.

Comments

[Sabata]

Coleman made a plastic bit called the Green Key that they included with their propane cylinders. Once the tank was "empty" you inserted the Green Key into the cylinder's valve. This allowed the last of the propane to slowly escape out of the cylinder so it was safe to recycle.

I just checked Coleman's site and it says that the idea didn't catch on so they aren't including the Green Key with their cylinders anymore. That doesn't mean a person couldn't locate one or two if they wanted to try this project without fear of fire/explosion.

Link: http://www.coleman.com/coleman/recycle/cylinder_dis.asp

[DIY-Guy]

Sabata-
As an alternative method of "safeing" a propane can before cutting it, someone here at Instructables suggested filling it with water to displace and absorb any traces of gas. Maybe the author or someone else will recognize which -ible talks about using water to make an empty propane tank safe for cutting.

[tylerpienta]

make shur u clean out the inside bc there would be gas residue and u put food in ther soo yea....

[spartancaver]

If you want to do this, try to find a local company that sells Liquefied Propane (LP) gas in bulk. i.e. a home propane dealer. Like Hank Hill who sells propane and propane accessories. These companies should have the old style propane tanks laying around gathering rust. Meaning the new tanks have Overfill Protection Device OPD's and are identified by the triangle valve. The old tanks have a star shaped valve knob. These can not be used unless retro - fitted with the OPD's. Since a new OPD cost about as much as a new tank; people will leave their old non-OPD tank and go buy a brand spanking new one. The propane dealers should be in the local yellow pages under LP dealers. Ask around if they have any abandoned old style tanks. I would not tell them what you are about to do with them and say you are going to convert them into a portable air tank. Like to carry compressed air for filling low tires out on your farm equipment and don't want to take the shop's air compressor all the way out there.

[JamesRPatrick]

This is for a small lantern tank.

[beehard44]

idea: Bar fridge evaporative cooler

[b.steadman]

Gas is heavier than air, so it sinks. Invert the cylinder with the valve open, in a well ventilated space (outside) and leave for a few days, then fill with water, as per BigShotUKs instructions. It should then be safe to cut open. I've had a cylinder in the inverted position for a month now

[JamesRPatrick]

Or use a coffee can.

[BigShotUK]

Leaving an open burner on top isn't really enough to purge the remaining fuel from inside the tank. The proper way to do that is completely filling the tank with water. It's easy enough with the large tanks if you equalise the pressure by opening the valve; then remove the valve by screwing it off; then filling the tank with water... I'm not sure how you'd do it with one of these small tanks but if you want to do this safely, that's what you need to figure out.

[JamesRPatrick]

It's very dangerous of course, but that's why there's a disclaimer. I understand your concern.

[Jesster_King]

I think this step might kill some people :/

[uz2bnuty4]

For something like this , I'd use a large coffe can. That's what I used to make ice cream once. My grandson really enjoyed rolling it back and forth over the carpet. (>_<)

[Marshal Banana]

That's cool. I never thought about reusing propane tanks for projects.