Quote:
Originally Posted by IKE
 You must be excedingly careful using an old tank (I have been dying to get to use that icon for a real purpose). |
Let me reinforce that sentiment three or four times over. If you are going to build one of these instruments, please heed the cautions in the instructions very closely. It is STRONGLY RECOMMENDED that you make the drum from a brand new, unused, empty propane tank. DO NOT attempt to make it from a used tank unless you really know what you are doing and have experience emptying, purging, and cleaning propane tanks.
I was assisted by someone that had worked at a propane distributor, and had experience installing/removing tank valves. Yet even with that, we still had to deal with enough residual pressure and contents in the tank to make things a little sporty as the valve came off. Without going into all the details, I will just note that there is a two-foot diameter spot in my back yard where plant life has not yet returned after a year and a half...
-dave
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