Here is my idea to reduce/elimate overspray with what I call the overspray shield. The blue area is a simulation of painted areas.
My test design will involve two hollow tubes on the side of my airbrush. A peice of styrene would be attached to two rods which would be able to slide in and out of the hollow tubes so you can get closer, farther, or completely remove the overspray shield. You can make shields in any shape, too.
Not sure if that won’t muck up your paint-job as paint will collect on the shield and start dropping off there as well as your spray-pattern will be affected.
Simply mask ALL the areas you don’t want painted and that should eliminate the overspray.
I see drips of paint forming on the “shield” and paint will draft up under your shield. It may reduce some overspary but not all. Looks like a pretty good idea, your on the right track!
Or how about having the shield on the bottom, with a bit of rolled tissue or some other absorbant material attached to suck up the excess paint build up?
Actually, what you’re making here is quite similar in theory to the “mobile masking method,” where you just hold a card or paper pattern in one hand on or over the model and spray with the other.
Plus, how can you see what you are painting with this long piece obstructing your view? If overspray is that much of a problem then get a large cardboard box and spray into that.