Gloss vs Flat

Both paints are acrylic. I only let it dry for a couple of hours. Looking at it seemed to be dry enough, but apparently not. For now on its best to let is cure for at least the 24 hrs. My lack of patience! Well at least I learned something. Thanks for the pointers.

I have the same problem with Tamiya flat base mixing technique. But recently, I just coating with Winsor & Newton matte varnish over the paint. I mix with a little future into W&N varnish to airbrushing easier. But wait at least two hours to let the varnish completely dry. Patient is a key if using this trick.

I agree with tho9900, it does sound as if you didn't let the base coat get completely dry before you applied the over coat. If you let the first coat dry at least 24 hrs (and 48 is better), then you should have no problems when you apply the second. And if you're not sure if the paint is completly dry, just smell it. If you can still detect the "paint" smell, then the paint coat has not completly cured. (that's an old trick model railroaders have used for years)

there should be no probs with spraying a flat over a gloss or vice versa... from what you described it sounds more like the coat underneath was not fully cured yet. How long did you give between coats?

what type of paint was the flat? enamel or lacquer or was it acrylic as well?