u/King_of_harem

Coating some blasted bare ductile Iron parts with this primer and getting bad rust bloom that requires 4+ coats to make it go away. Any advice?

Ductile Iron casted parts being coated in a water based paint. Takes 4 to 5 coats to get the bloom dots down to a minimum if thats what it even is. Any advice on how to reduce or eliminate them?