Which nozzle size should I start with?
A 0.3 mm nozzle covers most tasks because it sprays smooth base coats yet still pulls a tight enough line for post-shading. When you move to mottling on aircraft or small lettering on figure bases, drop to a 0.2 mm or 0.15 mm tip so you can throttle the paint down without spidering. For thick primers, clear coats, or metallic flake, jump up to 0.5 mm and thin the paint a touch less.
What psi should I use for airbrushing models?
Most hobby acrylics run happily at 25-35 psi once you thin them to a skim-milk feel. Drop to 10-12 psi when you switch to a 0.2 mm tip for fine lines, but push to 35 psi only for heavy primers or clear coats. Always test on scrap first, because humidity and paint brand shift the sweet spot.
How often should I clean my airbrush?
Rinse the cup every time you change colors, back-flush for ten seconds, then shoot cleaner into a spray pot so the dried flakes don’t spoil the next pass. After the last coat of the day, strip the needle, nozzle, and cap, soak metal parts for a few minutes and scrub the inside of the cup with a soft cosmetic brush.
How do I prepare parts before spraying?
Wash plastic or resin in warm soapy water to strip mold release, sand seams with a fine stick, and fill tiny gaps with putty. For 3D prints, clamp a sanding drum in a Dremel rotary tool and run it at low speed to knock down layer lines without gouging detail, then switch to a felt buffing wheel for a quick polish. Finish with a light scuff using a gray pad from your accessories kit, so the primer grips the surface, blow off dust, and the model is ready for paint.