2 Aug, 2019 Cast Iron Radiators Ever thought about getting your cast iron radiators repainted? Let us do the job for you. Here’s an example of a recent cast iron radiator that we sandblasted, primed and painted. Here we have the cast iron radiator laying on its side as we begin to sandblast the old paint off of the radiators. This is what the radiator looked like once we finished sandblasting it. Once we finished with sandblasting the cast iron radiator, we added a primer paint to them to allow the finishing paint to adhere to the radiators better. This is what the radiator looks like after it’s been painted.