Part 2 is proper metal prep under body filler without using epoxy.
♦️In a lot of cases, it is ok to do body work directly over well prepped bare metal.
♦️The exceptions would be higher humidity climates, or if it’s going to take a long time to do the body work. Then, it would be encouraged to epoxy the metal before body work.
♦️Cleaning and prepping the metal very well is the key.
♦️Clean bare metal with wax and grease remover.
♦️Media blast any welds or rust pits until completely clean, white metal.
♦️Clean with a non acidic metal cleaner and a scotch brite. (Glasurit 360-4)
♦️Clean with wax & grease remover.
♦️Option 1: D/A sand metal well with 120 or 150 grit.
♦️Option 2: Clean metal with a 3M clean and strip disc at low speed.
♦️Clean again with wax & grease remover.
♦️Grind metal, at a low speed, with a sharp roloc. 60 grit 3M cubitron 2 (they are purple) work very well.
♦️Blow off metal very good.
♦️Spread body filler over freshly prepped metal.
♦️Most importantly, by very meticulous with how clean the metal is.