Airbrush Help

So, I started painting my armour plates last night, and aside from some issues with getting an even coat (something I'm struggling with in particular with Humbrol greens), I was happy with it for a first coat. So I come back today, crack open my Green 117 and start working on the ab plate. But, despite using the same pot and the same paint/thinner ratio, I noticed I was getting a lot of frosting and the colour was significantly lighter when dried. I thought I'd put in too much thinner, so I tested with less, and continued until I was using way less thinner than I should be and I was still getting horrible frosting. Can anyone shed some light on this? Has my pot of paint gone bad overnight?

Here's a picture of the issue although I don't know whether you'll see it clearly, but you can definitely see the colour difference.


What's going on? and does anyone have any advice for Humbrols? Blues, reds, even yellows go through my airbrush fine, but Green 78 and 117 so far have given me terrible coverage.

Could be a bad batch? How are you mixing the paint? Stirring it up with a machine? or shaking it? the paint can settle and get thick at the bottom....

I tend to shake it first, then stir it if it sounds a bit runny. It does seem a little thicker than it did last night though, so maybe that's it.

Had a similar experience when painting my helmet.
I think it came down to the paint being fairly old.



You could try to thin it a tad more but you might have to paint more than one layer to cover it.

Edit : Forgot to mention heat can also affect the consistency of the paint, ie. if its really hot the paint starts drying as it exits the gun and that can create a "powder" effect on the subject.

If you don't have an electric stirrer look into it.

I definitely consider one if it helps.

I bought a couple more tins of 117 yesterday and put them through the airbrush. After re-priming, no more frosting, although the green is a lot greener than before.

Possibly due to a thicker coat, but if it persists, I think I'll tone down the green with the black misting on the ab plate, and possibly green 78 misting on the pec plates.