CNC Milling | G89 Cycle | Boring

G89 Cycle Introduction

G89 cycle is used to bore a hole. This cycle is almost the same as G85. The difference is that this cycle performs a dwell at the bottom of the hole.

G89 Cycle Format

G89 X_ Y_ Z_ R_ P_ F_ K_ ;


X_ : Hole position data
Y_ : Hole position data
Z_ : The distance from point R to the bottom of the hole
R_ : The distance from the initial level to point R level
P_ : Dwell time at the bottom of a hole
F_ : Cutting feed rate
K_ : Number of repeats (if required)

G89 Cycle Examples

G89 CNC Program Example – 1

M3 S100 ; Cause the spindle to start rotating.
G90 G99 G89 X300. Y-250. Z-150. R-120. P1000 F120. ; Position, drill hole 1, return to point R then stop at the bottom of the hole for 1 s.
Y-550. ; Position, drill hole 2, then return to point R.
Y-750. ; Position, drill hole 3, then return to point R.
X1000. ; Position, drill hole 4, then return to point R.
Y-550. ; Position, drill hole 5, then return to point R.
G98 Y-750. ; Position, drill hole 6, then return to the initial level.
G80 G28 G91 X0 Y0 Z0 ; Return to the reference position
M5 ; Cause the spindle to stop rotating.