Some Info About Painting With Enamel.
Understandable Rusty except for the fact that preparation is everything and there isn't a day that goes by when I haven't painted whatever kind of substrate without using a hardener where-as the paint scrapes off easily. Lessons learned makes for a better outcome and a great big smile even if its your own :)
Painting any substrate with a spray bomb like Rustoleum needs to be prepared for paint in order for the paint to stick