I will try to be specific as possible.
I used an old test spoon, which I sprayed with Tamiya X-7. I airbrushed the paint like 2 weeks ago, so there shouldn't be an issue when it comes with paint curing.
The spoon was a plastic spoon. I did not prime, or sand with 3000 grit to make the paint stick. I straight up took the plastic spoon, the nimmediately sprayed it with red without doing anything to the spoon. I would also like to point out the spoon was glossy plastic.
I sprayed a light coat of Tamiya TS-13 to the red spoon. I put it inside a small drying box, which I fashioned from an old Gundam box. I added holes to it so the air can circulate.
After I let it dry inside the box for 7 minutes, I took the red sppon out of the box, but then I noticed a thin red line which was with contact with the red spoon and the tissue (I added to stop paint from sticking to the box). I didn't really care, since it was only a thin curved line of red.
I then sprayed the spoon with a heavy coat. I will add that maybe it was a little to heavy, the clear coat, when I added the 2nd heavy coat. I then put it back to the box to dry for 20 minutes.
When I came back, I saw that the spoon looked messy. I picked it up, and the spot where there was only a this curved line of red, it became a noticable stain (spoon for reference). The other parts in the box were primed and was dried with the red spoon.
I checked out the spoon and investigated it, and I was distraught to see that it had ruined the base coat, where it showed the bare plastic of the spoon.
The bare spots are a little more noticable in real life.
I was glad that I did a test spoon first. If it was in the actual model, I would have gone crazy. Can someone explain why this happened?
I'm guessing that since I did not add a primer, the red did not have anything to grab on the smooth glossy surface of the spoon, which then got dissolved after applying the Clear.