I thought rust was something that happened in months or year. Holy crap, this this flash rusted in minutes after I sprayed on the phosphate, let it start to flash over, then wiped it off with a damp rag. Didn't read the instructions on the phosphate etch/prep - it said leave it overnight before wiping it off. Hit it with the phosphate prep and scotchbrite pad, wiped off the excess with a dry rag, then lightly coated again and left it overnight. Should be ready to clean off today, then start some patch work.
Learning as I go.....