AHA !
The plot thickens .I will ask you now .How long before you sprayed , did you shake the can and how Clean was the model's surface .These are very important factors here . I found out , quite by accident I might add.
.I bought some Paint in a spray can .( brand is unimportant ) I sprayed a client's model .Had to strip the whole darned thing . Maybe there was a bearing on this , that when I checked the can to see if I did a no - no I found out the can was over five years old Before I had purchased it .
In dealing with paint from a body shop ownership stand point - paint formulations change every year ( slightly ) .Now with the shift to non-cfc's in the propellant this affects the end results in that , it can ( I asked a Chemist ) change the very nature of the product .
So you could have two cans , different batches , that are sensitive to this . And this could be different from the primer to the surface the paint is going on too .
Years ago , I loved my paint jobs that were perfect because I used a tack-rag ( or cloth ) to prep them for paint . Bought some different brand ones and the paint already on the subject got tacky and wouldn't set after I used these rags .Turns out , that company used a cleaner enhancer that should not come in contact with model level or house - hold paints .
I hope this explains some of what may be wrong here .Also , did you wash the model well and RINSE it well and let it air dry Before you sprayed it ? ( another point to consider ) .Bye . Tanker - Builder