I welded up my own fire mops, the mud flaps from big trucks I use haven't melted(the just get lots of soot on them and really hot). They start to burn a little. For anyone who has burned tires it takes a lot of heat to burn rubber. But like I said it doesn't melt it just gets a soot layer on it. I've also made fire mops out of sheet metal, but they dont conform to the ground as well as the rubber mud flap.
