Hi all. I just posted pics of my F-14 in the Group Build section, I painted it last night. I have run into this problem before, and I’m wondering if anyone else has had this.
When I airbrush lighter shades of grey, particularly light and dark ghost grey, I get a lot of “pebbling” of the paint, it seems to roll-up and just be everywhere. I think the paint may be too thin, but I’m not sure. I’m airbrushing somewhere around 15 psi, with a Paasche H airbrush, #3 needle and tip. I’m using Testors MM Enamel Airbrush Thinner to thin these, I’m thinning between 1:1 and 3:2 paint to thinner.
Sounds like you are over thinning. I use Modelmaster enamels almost exclusively & also use a Paasche H3. I usually spray closer to 20psi with the paint thinned no more than 3:1 paint/thinner. I use either Mineral Spirits or the ModelMaster enamel thinner.
I’ve had something similar happen to me when the paint hits angles and bounces around a bit. It dries in the air before settling on the model. I’ve usually corrected it by being careful about what angles I’m spraying on. I’ve been able to remove the little pebbles from the surface of the paint by brushing them off with an old paintbrush whose bristles I’ve trimmed down to about 1/4 inch. I just dusted them off with no damage to the paint underneath.
Another possible issue is that you spraying to far from the suface, such that the paint droplets mostly dry before hitting the surface, which will give sort of a pebbly appearance. Ideally the paint should lay down somewhat wet.
It all comes down thinning, air pressure, painting distance, and much your tip is opened up. Practice on some scrap plastic or an old model.