I showed up to a commercial job this morning to remove rust on painted hardiboard (?) I’m using oxalic acid and water. No fancy stuff on this one. It worked beautifully, but I had apply… and reapply… and reapply. Anyone ever use elemonator (or whatever your surfactant of choice is) and oxalic acid?
Any weird reactions? The apartment complex just found 3 more exterior fire sprinkler heads with the same rust running down the exterior siding. It’s new construction, not even finished yet, and the paint is less than a month old.