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G86/G87/G88: Special boring cycles

Boring variants with spindle stop, orientation, manual retract or back boring depending on the control.

For reference only: syntax changes with the control, the post-processor and the machine parameters. Check the official manual and run a simulation before cutting. Legal notice.

Family
Cycles
Machine
Milling, Mill-turn
Risk
Medium
Example
G86 X20 Y0 Z-25 R2 F80
E.g.:
G86 X20 Y0 Z-25 R2 F80

Parameters

X Y
Posición del agujero. Cada bloque con X/Y nuevos repite el ciclo en esa posición. · mm
Z
Fondo del agujero (cota absoluta con G90; incremental desde R con G91). · mm
R
Plano de referencia: cota Z a la que la herramienta pasa de rápido a avance y a la que vuelve entre agujeros con G99. · mm
F
Avance de corte. · mm/min con G94, mm/vuelta con G95 (en torno suele ser el modo por defecto)
Q
G87: desplazamiento con husillo orientado para entrar y salir sin rayar la pared. · mm
P
G88: pausa en el fondo antes de parar el husillo. · ms / s según control

Machine: Milling, Mill-turnRisk: Medium

Fanuc · Haas

G86/G87/G88 ...
  • Fanuc: The difference between cycles depends a lot on the control; check the hole retract.
  • Haas: Confirm stop/orientation and return plane.

Other codes in Cycles

G80 Cancel fixed cycleG98/G99 Return plane in canned cyclesG81/G82/G83 Drilling canned cyclesG84 Rigid threading on a milling machineG85-G89 Boring, reaming and hole cyclesG73 Fast pecking drillingG74 fresado Reverse tapping / special milling cycle
See the full list of G and M codes

Frequently Asked Questions (FAQ)

What does G86/G87/G88 mean in a CNC program?

Boring variants with spindle stop, orientation, manual retract or back boring depending on the control. In the catalogue it appears as "Special boring cycles", within the Cycles family.

How is G86/G87/G88 written on each control?

Fanuc: G86/G87/G88 ... · Haas: G86/G87/G88 .... The exact syntax depends on the control version and the machine parameters: always confirm with the manufacturer's manual.

Can you give me an example of G86/G87/G88?

G86 X20 Y0 Z-25 R2 F80 — Boring variants with spindle stop, orientation, manual retract or back boring depending on the control.

Which machines use G86/G87/G88?

G86/G87/G88 is used in: Milling, Mill-turn.

What should you watch out for with G86/G87/G88?

Medium risk: it rarely breaks anything on its own, but a wrong value shows up on the part. Check the block before running the batch.

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