Set the first 17 flush rivets of the whole project. I had to drill the second one out because the bucking bar partially slipped off the rivet and ruined it. I got better as I went, but shooting and bucking by yourself isn't all that easy. I bought one of the tungsten bucking bars, and it worked great. All its surfaces are polished so you can use whichever face of the bar fits the situation best. Only 14983 rivets left to go.
