A Beginners Guide to Canned Cycles for Milling (Fanuc)

Introduction

• CNC programming involves learning numerous codes and cycles.
• Understanding these codes is crucial even with CAM software for debugging and program reading.
• This guide introduces canned cycles for CNC 3-axis mill programming using Fanuc controllers.
• Canned cycles automate repetitive tasks like drilling.
• Fanuc-based machine controllers generally have consistent canned cycles.

What is a Canned Cycle?

• A command for automating a pattern of movements in CNC machines.
• Simplifies repetitive tasks by using a set of motions instead of programming individual movements.

List of Canned Cycles for Fanuc Mills

• G73: High Speed Peck Drilling
• G74: Left-Hand Tapping Cycle
• G76: Precision Boring Cycle
• G80: Canned Cycle Cancel
• G81: Standard Drilling Cycle
• G82: Counter Bore Cycle
• G83: Deep Hole Drilling Cycle
• G84: Right-Hand Rigid Tapping Cycle
• G85: Reaming/Boring Cycle
• G86: Boring Cycle
• G87: Back-Boring Cycle
• G88: Boring Cycle
• G89: Boring Cycle

Detailed Breakdown of Canned Cycles

G73 High Speed Peck Drilling

• Also known as breakchip drilling.
• Used to break up long, stringy chips which can damage tools and workpieces.
• Key Parameters: X, Y, Z, R, Q, F, K.
• Suitable for holes 1xD to 4xD depth.

G74 Left-Hand Tapping Cycle

• Similar to G84 but for left-hand tapping.
• Rigid tapping preferred using M29.
• Key Parameters: X, Y, Z, R, F, K, M29.

G76 Precision Boring Cycle

• Used for precision boring without tool retraction marks.
• Suitable only for single-fluted boring bars.
• Key Parameters: X, Y, Z, R, Q, P, F, K.

G80 Canned Cycle Cancel

• Stops the repetition of active canned cycles.

G81 Standard Drilling Cycle

• Basic hole-making cycle.
• Rapid retract after drilling.
• Key Parameters: X, Y, Z, R, F, K.

G82 Counter Bore Cycle

• Similar to G81 with an added dwell at the hole bottom.
• Suitable for counter boring and spot drilling.
• Key Parameters: X, Y, Z, R, P, F, K.

G83 Deep Hole Drilling Cycle

• Used for deeper holes (4xD or more).
• Retracts tool to clear chips.
• Key Parameters: X, Y, Z, R, Q, F, K.

G84 Right-Hand Rigid Tapping Cycle

• Commonly used tapping cycle.
• Rigid tapping synchronization is crucial.
• Key Parameters: X, Y, Z, R, F, K, M29.

G85 Reaming/Boring Cycle

• Similar to G81 but feeds up on retract.
• Allows for spring pass.
• Key Parameters: X, Y, Z, R, F, K.

G86 Boring Cycle

• Includes optional dwell and spindle stop.
• Faster than G85.
• Key Parameters: X, Y, Z, R, P, F, K.

G87 Back-Boring Cycle

• More complex; used for back-boring.
• Involves tool offset and spindle orientation.
• Key Parameters: X, Y, Z, R, I, J, K, F.

G88 Boring Cycle

• Manual retract; less common.

G89 Boring Cycle

• Similar to G85 but with dwell time at the hole bottom.

Conclusion

• This guide is a basic introduction to Fanuc canned cycles for milling.
• Understanding these cycles enhances efficiency and precision in CNC machining.