HEIDENHAIN CNC Pilot 4290 - Manual (Page 380)

7 Parameters 368
7.5 Mac
hining P
a
ra
met
ers
Drilling - safety clearances
■ Internal safety clearance [SIBC] – for deep-hole drilling (retraction
distance B for G74).
■ Driven drilling tools [SBC] – Safety clearance for driven tools on
end face and lateral surface
■ Non-driven drilling tools [SBCF] – Safety clearance for non-driven
tools on end face and lateral surface
■ Driven tap [SGC] – Safety clearance for driven taps on end face
and lateral surface
■ Non-driven taps [SGCF] – Safety clearance for non-driven taps on
end face and lateral surface
Drilling - Machining
The parameters apply to drilling with deep-hole drilling cycle (G74).
■ Drilling depth factor [BTFC] – 1st drilling depth: bt1 = BTFC * db
(db: drill diameter)
■ Drilling depth reduction [BTRC] – 2nd drilling depth: bt2 = bt1 –
BTRC; the following 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
10 – Milling
Milling - Traverse from/to tool change position
■ Approach, end face [ANMS]
■ Approach, lateral surface [ANMM]
■ Depart, end face [ABMA]
■ Depart, lateral surface [ABMM]
Entries for retracting a tool:
■ 1: Simultaneous, X and Z direction
■ 2: First X direction, then Z
■ 3: First Z direction, then X
■ 6: Coupled motion, first X, then Z
■ 7: Coupled motion, first Z, then X
Approach and departure are in rapid traverse (G0).