Adjusting a Microstop Countersink - 1donagin This video is part of a series from Southern Illinois University in Carbondale, IL. This is from Project 1, and is part of a much larger video. This one shows how to adjust a microstop countersink to countersink the rivet holes consistently. By the way, the rivet should range from exactly flat on the surface up to 2 thousandths of an inch above the surface (proud). If you can catch your nail on the edge of the rivet, it is too high.