A buddy of mine who does alot of welding told me he was a little skeptical on doing any welding on any refurbished propane tanks. He said that the fumes can be contained in the steel inside the tank and performing any welding he said could cause an explosion. Has anyone ever run into this issue? I know alot of you guys have dont welding on the propane tanks to accomplish making your own storage. Should he be worried about this? If the tank is flushed with bleach and water for a few cycles, wont the gas vapors and smell be gone? Any help would be great.