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8-33
8
Cycles
TNC 426/TNC 425/TNC 415 B/TNC 407
Fig. 8.39:
Possible infeed point for
PILOT DRILLING
Y
X
PILOT DRILLING (G121)
Application
Cycle G121 is for PILOT DRILLING of the cutter infeed points. It accounts
for the ALLOWANCE FOR SIDE and the ALLOWANCE FOR FLOOR as
well as the radius of the rough-out tool. The cutter infeed points also serve
as starting points for milling.
Sequence
Same as Cycle G83 PECKING.
Input data
• PECKING DEPTH Q10
Dimension by which the tool drills in each infeed
(negative sign for negative direction)
• FEED RATE FOR PECKING Q11
Traversing speed of the tool in mm/min during drilling
• ROUGH-OUT TOOL NUMBER Q13
Tool number of the roughing mill