The cause to your problem is usually cause by applying the paint to thick, as it dries, the excess runs to the edge of the object. You could apply another thin coat, but I would determine is you are going to lose any molded detail. I tend to keep a bottle of clear gloss coat, and mostly airbrush my pieces. Rattle cans are convenient, but not always reliable. I especially find this with the Tamiya ones, even the lightest coat seems to go on pretty thick.