Ive seen airbrush and paintpens on finished hotcoats but has anyone tried spraypaint? If so what kind of results did you get?
check the archives, this question has been asked about 4 times in the past month… good luck es http://www.surfboardglassing.com
as far as im concerned airbrushing is spraying paint… if you mean cans of spraypaint then thinner base acrylic will work altho its hard to control the cans with thier crap nozzles. todays common board sprays by kids in the backyard use this style and it is quite acceptable over here on oz! http://www.feraldave.com 
…lost surfboards has been putting out a lot of boards that appeart to have been sprayed with spray paint along with hand drawn detail work. almost any spray paint will work over the hotcoat. what you seal it with is what can break the deal. make sure your clear coat is compatable.