After drilling the holes, turn the jewelry over and clean up the back of the plate. If the plate is thin, all you can do is scrape away any burs and polish with a bristle brush. If the plate is thick enough, you need to cut away some of the metal surrounding the holes. These cuts are called azures. Azure is the American English derivative of the French term a jour or adjoure.
The easiest method to cut an azure is to taper the hole using a bud or cone bur. Then polish the taper with a hard felt point in your flex-shaft.
On finer jewelry, you will want to cut a square or triangle shaped azure. The results look like bright cutting on the backside of the jewelry. To begin, cut a tapered hole with a bud bur. Then, using a hart bur held sideways cut your corners in each hole. Next, use a small wheel bur to clean away the metal between the corners. Then use a polished flat graver to clean up and polish your cuts.