Two weeks. For this helmet;
I was using the Welshwarior's youtube tutorials on the ESB paintjob, and had a vaccuum box for the airbrush, so I could paint at home. I used Humbrol paints which needed some 10-12 hours between layers to dry, and had a deadline for my Fett to be complete.
Two weeks, from start to finish. After work, I buffed the previous work with steel wool, and masked the next layer, then, some jogging outside to let the masking fluid dry, and paint. Then, few hours of sleep and repeat. Then to work, and another coat after work.
I did two - three layers per day, and was able to complete the bucket in time. No social life during those two weeks. Nada...
If I were to paint another bucket, I would take a month to do it, so I could have SOME free time....