I am trying to take apart a steel frame, and right now I am working on the top tube. I cut the top tube at the upper headtube lug and I am trying to heat the seat lug and pull the top tube out. This does not seem to be working, it doesn't move at all when I try to turn/pull it when the lug is heated up. Any tips? Would it be better to cut the tube and grind the extra out?