This is a video of my 5 gallon propane tank that I made years ago that is still working without problems. Great for cooking hamburgers, hotdogs, etc. Small enough to easiy take with you on your camping trip but big enough to cook for the whole family. Can cook up to 10 medium burgers at once with room to spare. Check it out, at least it will give you some ideas if you are thinking of building one.
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