Looking for best way to prep galvanised gutters which have paint peeling. Do I remove all the paint with mechanical wite wheel and sanders? Or do I rub as much as I can with 180 wet and dry to save work? Then prime with galv primer then 2 coats of weather shield. Main concerns are, if I don’t take all the paint off you will see it under the paint or the primer lifting the paint that is left on?
