Since I hadn't done much airbrushing (took a class that was more about t-shirt design and primed some parts for a project I never finished years ago), I decided to clean my airbrush and practice on some spoons with Vallejo acrylics. I'd prefer not to use anything but water-based acrylics, so I wanted to see what what the metal colors looked like. I read that for the aluminum color, I should prime first with Vallejo gloss black primer and then do the metal color coats. I practiced on a few spoons just to get the hang of how much paint to use and controlling the airbrush and by the time I did a few, i felt confident enough to try my engine block.
Here is what my setup looks like:
Here is the block after one light and one medium coat of the gloss black primer:
And here are a few pictures of the block after a couple of coats of the Vallejo Metal Color Aluminum:
The lighting wasn't great for these pictures, but in person I think it actually looks metal-like for water-based acrylic. Anyway... not much progress, but I feel comfortable with my airbrush again!