Hello my dear friend. Few tips on spraying. I think that you have thinned the paint too much (very poor coverage and multiple passes required). When you mask always use 1 single length of tape to mask the entire ship side. The line created this way will be nice and even. Finally the best spray practice is to do overlapping passes where a new pass covers 50% of the previous pass. Finally use other airbrush when touching up the parts missed using flat pattern or change to the round airbrush tip. Wishing you the very best from United Kingdom.