Operation Manual

HEIDENHAIN CNC PILOT 640 579
8.2 Parameters
Drilling – Machining
The parameters apply to drilling with deep-hole drilling cycle (G74).
Milling
Milling – Approach and departure
Approach and departure are at rapid traverse (G0).
Machining
Drilling depth factor [BTFC]
1st drilling depth: bt1 = BTFC * db
(db: drill diameter)
Depth reduction [BTRC]
2nd drilling depth: bt2 = bt1 – BTRC
The subsequent drilling steps are reduced accordingly.
Diameter tolerance for drill [BDT]
For selecting the desired drill (centering drills, countersinks,
stepped drill, taper reamers).
 Drilling diameter: DBmax = BDT + d (DBmax: maximum
drilling diameter)
 Tool selection: DBmax > DB > d
Approach and departure
 Approach – end face [ANMS]
 Approach – lateral surface [ANMM]
 Departure – end face [ABMS]
 Departure – lateral surface [ABMM]
Approach/departure strategy:
 1: Move simultaneously in X and Z directions
 2: First X, then Z direction
 3: First Z, then X direction
 6: Coupled motion; X precedes Z direction
 7: Coupled motion; Z precedes X direction