CNC 드릴 고정 사이클 (G81, G82, G83, G73)
Canned cycles condense complex multiaxis peck drilling and retract sequences into a single modal G-code block. Understanding the mechanics of retraction planes (G98/G99) and chip evacuation cycles prevents tool breakage and workpiece collision.
G81: Straight Drilling
No Dwell / No PeckFeeds continuously from reference plane R to final depth Z at programmed feed rate F, then rapids straight back out. Ideal for shallow holes (< 3× diameter) and spotting.
G82: Counterbore with Dwell
Bottom Dwell (P)Feeds continuously like G81, but pauses (dwells) at hole bottom for P milliseconds (or seconds) before retracting. Cleans up bottom face finish and eliminates cutter bounce.
G83: Deep Hole Full Retract Peck
Full Clearance (Q)Drills incrementally by peck depth Q, then completely rapids back out to the R plane to evacuate chips and flood flutes with coolant. Essential for deep holes (> 3–5× diameter).
G73: High-Speed Chip Break Peck
Fast Relief (0.5mm)Drills by Q depth, then backs up only 0.5 – 1.0 mm to snap the chip string before immediately resuming feed. Greatly reduces cycle time when deep clearance isn't required.
Return Plane Mechanics: G98 vs G99
Every canned cycle requires choosing between two modal return planes:
After completing the hole, the spindle rapids all the way back up to the Z height it occupied before the canned cycle was called.
The spindle retracts only to the programmed R plane (usually 1.0 - 2.5 mm above the part face) before moving to the next X/Y coordinate.
Crucial Safety Rules for Canned Cycles
- Always Cancel with G80: Canned cycles are modal. If you move X/Y on the next line without commanding
G80, the machine will drill another hole at that location! - Always Specify Decimal Points: In Fanuc controls,
Q2without a decimal point is interpreted as 0.0002", causing endless micro-pecks. Always programQ2.0. - R-Plane Below Surface Danger: Ensure your R plane is positive relative to the part Z0. Setting R below the workpiece face causes the drill to rapid directly into solid metal.
Interactive CNC Canned Cycle Generator
Generate ready-to-run Fanuc & Haas G-code with PCD bolt hole circles, coordinate arrays, and automatic peck schedules.