what is the metal on the center of the motors you take out is it lead or alluminum? should i save them and stick them in a campfire to melt the metal off the steel is it worth it? i believe there called rotors if its lead or alluminum it will melt regaurdless right? will it burn up like a can and disapear or will i be able to sift through the ashes to find it? will the scrap yard take em if its ali and what will they call it?