Re: [VAC] Rivet Tools

["Dr. Gerald N. Johnson, electrical engineer" <geraldj@xxxxxxxx>]

Its appropriate to drill out pop rivets and other rivets with an
undersided drill because the drill tends to drill overside. That's
because the drill wobbles on the center web and the two cutting edges
tend to have slightly different lengths. Even if the center doesn't
wander, those drills make oversized holes. Worse the remaining mandrel
of a pop rivet tends to be harder than the outside of the rivet that
tends to drive the drill bit to the side.

Once a hole is drilled undersize, its easy to open it up with the
perfect sized drill, though if the size difference is small, there is a
tendency for the bit to grab.

Gerald J.