CNC | G98 and G99 Code | Return Point Level

G98 and G99 Codes Introduction

G98 and G99 codes are use with drilling cycles like G81, G83, G84 and etc.. for CNC Milling machines (CNC Machine Centre)

G98 and G99 Codes Format

G98 Code

G98 ;

When specifying G98 code, the tool coming from the bottom of a hole, returns to the initial

G99 Code

G99 ;

When specifying G99, the tool returns to the R level from the bottom of a hole.

Things to Know

The figure below describes the movement of the tool when G98 or G99 is specified.
G99 is generally applied for the first drilling operation, while G98 is applied for
the last drilling operation. Even when drilling is performed in the G99 mode, the
initial level does not change.

Return point level (G98/G99)