Version:
Very sturdy. Tight concentricity tolerances between drill ⌀ and counterbore ⌀ guarantee exact alignment.
Advantage:
Hole and countersink are produced in one operation and precisely aligned.
Application:
Particularly suitable for NC machines due to high positional accuracy, excellent centring properties and great sturdiness. The preceding centring operation can thus often be omitted. For thread tapping drill holes to DIN 336 sheet 1 with 90° countersink. In the following operation, the tap therefore does not have to cut into the sharp edge of the hole.