Got to the hardware store and get you a box of fresh 7011 or 6013 rods so you know they have not been exposed to moisture and crank it up kinda hot and practice on a scrap piece and turn it down till you find that sweet spot.
beat me to it but try 7018 if that dont work and heat the hell out of it, i havnt messed with sometin like that but you need somethin high grade
and mod93dirt ive been on the farm since i was 6, got paid hourly and worked there till i was 18, learned to drive a 6 speed hi/lo tractor when i was 10