Paint removal question

If you are stripping a large area I would use chemical stripper as a first step. Home Repot sell Kleen Strip for less then the Aircraft stripper and work just as well, get the xtra strength, they have 3 different ones. The only time I grind is to remove surface rust. Any time you open the pores of the metal you invite rust. Brush grinded bare metal with OSPHO to prevent rust from ever returning. Hope this helps.