Johan, thanks very much.... I think the next steps on the clapboards will be some drybrushing with acrylics so the boards aren't so uniform in color...
Mike G: They do make small compressors for airbrushing, but honestly you could step down your 1/4" NPT fittings to 1/8" and use a good regulator to keep the pressure down.... typically I find myself spraying between and 20 and 30 psi... One problem with the tiny compressors they sell is that they run virtually non stop and get hot because most are air cooled.... I didn't want to stop today, but I think I am going to look into the reducer and use a different small air compressor that I own.
I just found this adapter kit on Amazon... looks like it has every different combination between 1/4 and 1/8 fittings...
https://www.amazon.com/Baugger...ctronics&sr=1-17h
My elevator was already assembled and glued, so I did all the air brush work and didn't worry about over spray on the roof panels as I knew I was going to brush paint them anyway... When I am done weathering the sides and trim, I plan to glue some finely sifted dirt to the plastic base... I will also plan to lightly airbrush a very light coating of dirt or drab color around the bottom of the entire elevator where rain would have splashed dirt up onto the first several rows of siding boards.
Mike try icing your lower back and take one tylenol and one ibuprofen together.... I know I am playing doctor here, but I have 30 year history of lumbar disk degenerations, herniations, one surgery (2002), for partial removal of a ruptured lumbar disk, so I am not just sharing a random opinion... Good luck, nothing worse than back pain !!!!