Let your magnet be your friend and use it so you know what kind of metals your dealing with. There might be a little stainless in those Fridges also, maybe in the tub of the washer (not too often). Not sure what kind of cooker your talking about, but if it's an electric plug in kind, like a "george foreman; then it's cast alum. Also might be a cast alum deck on the mower. Just thinkin' out loud here,,,