Prep
Prep
Prep
Prep

Practice
Practice

Trial
Error
Trial
Error

Somewhat
Somewhat

Success!

75% of the job is painstaking prep. Assuming steel. Oxidation to bare metal begins the instant it is bare metal. So, once prepped, some kind of coating needs to follow, asap, so not only do you prepare the metal frame, you prepare to coat it, as well.

I am not sure an airbrush is the tool, but flash on the edges of round tubing is the main issue. I would ask crank_addict on that one. He's painted, knows the business, the material, etc, and he's local enough.

There are "upper level" rattle cans that have had good results here on BF, and I imagine using an air compressor and sprayer may help. Many painters are now using HVLP process, with more volume, less pressure. There are complete sprayer systems available from $80 to $600 that advertise the flexibility you may need. Of course, there are much more expensive systems, but these are bikes.....

You would really need to determine what kind of paint you want to use, as far as primer, base, and possibly clear, and then see what system works for you. Do you want to wet sand in an hour, wait a day, etc.

I understand bake-on finishes, etc, but the best results, from my experience, come when you paint the frame, let it dry, and then put it away and forget it, let the calendar turn a few pages, then come back to it.