After the rust is gone, the acid is neutralised with baking soda and water. The parts will flash rust imediately after being cleaned this way. I found that if I soak them in EvapoRust for maybe 5-10 minutes, they won't flash rust. I rinse off the EvapoRust and dry them with compressed air. They end up looking like the one picture I posted. After that, they were sprayed with SEM self etching primer.
