Used the spray cans on the first rim looks bad...................2 things, the cans seem to kick out a little "dust" if you will so I cleaned them out between coats, the final coats you can still see its blotchy. I sanded with 2 different grits and used degreaser cleaner and then dawn, then tsp prep. Is it the spray can pain? It seems they need a thicker formula? Any help guys??