I’m guessing that you are using a battery-powered hand drill. The key to drilling clean holes for your shelf pins using the JIG IT® Shelving Jig or any jig, for that matter, is ‘drill speed.’ Corded drills work best for this task. Let the drill get up-to-speed (highest RPM setting) before plunging it into the plywood. Many of the battery operated models just can’t crank the RPM required or a low batter condition prevents it from getting up to the proper speed for a clean cut.