HI: I was at a very large flea market today. There was a person selling welding rod of some type that welded aluminum as thin as pop cans. She repaired / filled in 3/8 dia holes in the bottom of a pop can. She said it melted around 700 degrees. It looked very easy. No flux and she used a small stainless steel brush to clean weld aera, after a light sanding. A propane torch was ued for heat. Now the big question. How hot do exhaust systems get on our converted engines on gas and on glow fuel. Is it far less than 700 degrees? Has anyone had eperience with this stuff? It was $20 dollars for the rod & brush. Thanks Capt,n