I wanted to test paint a dud PLA piece I had that was made in a MakerBot. I used Scalecoat 1 and a 20+ year old now banned auto primer. This primer is **lacquer** with lots of smell to it! No problems!
I then put it in my train baking oven to 170 degrees to “bake the paint”. (:->) It mostly survived intact! I was rather surprised and impressed. I am not sure what would happen to a smaller or thinner walled item though.
See my layout progress at: