Re: Patching a gas tank
Joe, silver solder requires more heat then the rusty metal will probably take. Stick with soft solder, either 50/50 or 95/5.
The process is a lot like leading in we used to do on car bodies. The heat is critical to get the lead to flow but not ball up. Like Tinsmith said, make a dent so the lead has a slight depresion to fill. That will allow more material to seal and give you something to level out later before sanding and painting.
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