How to Peen a Rivet
- 1). Punch rivet holes in the two pieces of metal using a metal punch. The holes should be about 1/8 inch in diameter, or as large as your rivets (1/8 inch is a standard size).
- 2). Push a roofing nail through both holes, and cut off the extra length of nail on both sides of the metal using metal cutters. The extra nail sticking out on the top side should be roughly half the width of the nail and come to a point at the top.
- 3). Pinch the sides of the nail with pliers to create a sharper, more distinct point.
- 4). Place the metal pieces on an anvil. Bring the flat end of the peen hammer directly down on the nail tip to flatten it out. Hit the nail from different angles to spread the metal as you flatten it, then square the head of the hammer with the nail top again, and work from the inside out in circles, forcing the metal of your nail to spread out.
- 5). Turn the hammer over to the ball side, and repeat Step 4. You have now turned a nail into a rivet.
Source...