A NOTE ON PAINTING:
I use an airbrush with acrylic paints and have found an external-mix airbrush works best. Keep nearby a container of isopropyl alcohol diluted with water and occasionally run it through the airbrush, especially if you set it aside for a few minutes.
I use Frog Tape for masking because it has a moisture-activated sealer that prevents bleed-under. I use it with water-base paints. To be honest, I don’t know how it reacts to oil-base paints. After I apply the tape, I press it down with a Woodland Scenics Teflon burnishing tool. Then I take a no. 4 brush and wet the edges with water to activate the sealer. Be sure to let it dry over night; otherwise, capillary action will cause bleed-under. The tape peels off easily and doesn’t pull up the paint or leave a residue. Alternately, I’ve also had good results using blue painter’s tape and clear spray to seal the edges to prevent bleed-under.