This new Al/Al Stack Drilling series conducts the drilling for the rivet joints dry. The twin cutting edged carbide tool has an extremely positive cutting edge and a double point angle. This minimises burr formation and achieves better centring.
The coating of the drill prevents material adhesion to the cutting edge whilst a lead-in stage provides for an optimum bore quality and precision. With specially formed chip flutes, the Al/Al Stack Drills ensure optimum chip removal. For cooling the drills, air is applied to prevent overheating of both the cutting edge of the drill and also the immediate vicinity of the fuselage. By cooling the cutting area and the aluminium, the new drills prevent burr formation. This compressed air supply is also used to blow out the chips.
