"Issue with satin spray paint vs. flat?" Topic

So I have successfully used Krylon Colormaster paint + primer flat black on model plastic, namely GW plastics. No question of the adhesion and curing to a solid, primed finish.

However I recently tried to use the exact same brand but the color was brown and the finish was satin. Said on the can it bonds to plastic, "most plastics". But on GW plastic it seemed like it wasn't creating a bond and adhering or drying, it stayed tacky and gummy for lack of a better word.

Would the satin finish have anything to do with it not adhering to model plastic properly? Something chemically in satin that would be an issue with plastics?

I know that with some Krylons and Rustoleums only the primers or paint/primer combos will properly work on model plastic, the regular sprays can be hit or miss with adhesion, even the ones that say they're plastic. Some seem like they're meant for more like lawn furniture or like automotive plastics but not model styrenes.

Just looking for thoughts and experiences.

Can't answer your question directly, but I have a different problem with satin finishes, and that is that the "sheen" prevents the paint from adhering to it properly.

Same as 79thPA – I tried using satin as a base for a miniature once to see how it would work (only place I could find the color blue I was after) and it was a total waste.

It adhered to the miniature just fine – but it was a metal miniature.

Base primer needs to be flat, satin or gloss does not provide a good base. Any gloss finish, and to a lesser degree most satin finishes, are designed to shed dirt and water.
Also, why don't you use white or light grey? Lighter colored base/primer coats tend to make uniform colors "pop" especially the lighter colors.