Auto body repair & detailing: rattle can rust repair, spray pattern, dupli color

Question
How do I repair a paint rust bubble on a panel with a dupli-color rattle can? If I sand to metal and fill with primer/filler, the spray pattern of a rattle can is so rough I feel I may have to sand the base coat before I apply the final clear-coat. Should I spray the entire panel or fender/quarter with clear-coat or just blend clear after sanding base coat repair with 1500 wet?

Answer
Bret i would build up the primer spray a few coats wet sand it,spray a few more coats sand it each time making the spot you prime wider and wider each coat.yes you might have to sand some of the base just to make sure it blends together well.I would just blend the clear after sanding the base area around it just make sure you blend the clear out far enough.