Online Tips Index / General Shop Tips / Cam-Action Fasteners
A cam-action knock-down fastener needs to fit tightly in its hole to create a good, tight joint. And the depth of the hole is critical, too. But once the plastic cam is tapped into the hole, its tough to get it out again to adjust the depth of the hole without damaging the fastener.
To ensure that the depth is perfect the first time, I set my drill press depth by drilling a hole in the edge of a test piece. Of course, the test piece must be exactly the same thickness as the workpiece.