I have painted a pretty good number of bikes, over the past few years. When I had "GrinderBikes" rolling, selling fixed-gear conversions over the internet, I offered a choice of existing paint, powdercoating, or the good-ol' rattlecan paintjob.
A surprising number of people chose the rattlecan option, despite knowing all of the problems associated with spray paint. Spray paint is notoriously fragile, due to the high solvent content it needs in order to spray evenly. All of that solvent also makes it prone to orange-peel. But, for many of the people to whom I sold bikes, it was the best way to go, if they wanted a personalized bike, because it was more affordable than powdercoat.
I actually got pretty good at it, but not as good as my friend Don Fox. When Don rattlecans a bike, it looks like it just came from the custom automotive paint shop. Of course, Don was a custom automotive body man and painter, very active in the local hot-rod and drag-racing scene, back in the 50s, 60s and 70s here in Denver.
Now, Don rides a bike or walks everywhere he goes. At 78 years old, he's not real fast, but he is tenacious.
(One day, I would like to write a book about Don. He is a treasure trove of local gear-head history.)
The first bike I ever painted was Brad's Trek 400 singlespeed conversion. He and I pulled the braze-ons off of the frame, and prepped it for paint in the unheated garage of the duplex I rented on Sherman Street. The temperature was in the 20s, but we just had to go ahead and spray it.
So, we got my hair dryer out, and heated the tubes of the bike up, then sprayed the paint onto the warm tubes. Then, once we had it covered, we stood there and blow-dried the paintjob until it was dry to the touch.
It suffered from a bit of orange peel. But, for the conditions under which we painted it, it came out pretty nice.
My favorite paint job I ever did on a bike, though, was on my Specialized RockHopper 700c fixed gear conversion that I called "The Ghetto Bike". The original yellow paint on that bike was pitted, scratched, faded and just generally dingy. So, I painted over it with two full cans of International Orange spray paint.
I held the can too close, on purpose, and laid the paint on as thickly as I possibly could. When it ran or dripped, I wiped it with a paper towel, and re-sprayed that spot. I was attempting to fill the chips and scratches with the new paint, and have enough thickness to smooth out the finish.
Oddly enough, doing everything wrong, I ended up with a paint job that got more compliments than any other bike I've painted, before or since.
I sold that bike, somewhat later, and I still miss it. I have another of those old tig-welded RockHopper frames out in the shop building. And, it has terrible paint on it....