With all the different way's people tell you to weld a gas tank I wanted to tell you what worked for me. The gas tank on one of my bikes started leaking where I had a 1/8 pipe bung for a fuel gauge. I drained the tank and let it sit in the sun for two day's. I then filled the tank with Dawn detergent and water. people say it has to be full with out any air pockets. If it is completely full you will never get it welded with out water coming out where you are welding. I had the tank about 7/8 full and tig welded it with silicon bronze rod with no problems. Just wanted to let you know what worked for me.