G83

G83 is a drill canned cycle used in computer numerical control (CNC) machining, primarily for peck drilling. It is employed to machine holes with repeated small plunges to clear chips and reduce tool chatter when drilling deep holes. The cycle is typically invoked after positioning the tool at the hole center and specifying a starting depth.

Operation: The X and Y coordinates locate the hole center. Z defines the final depth of the hole (negative values are common in many coordinate systems). R specifies the retract or clearance height above the hole; the drill retracts to R between pecks. Q defines the depth of each peck (the incremental depth per pass). F sets the feed rate for the drilling moves. When G83 is executed, the tool plunges from the R plane down to the final depth in increments of Q until Z is reached; after each peck, it retracts to R, advances to the next peck, and repeats. After reaching Z, the cycle retracts to R (or to a safe plane) and the program continues with the next move.

Example: G83 X10.0 Y5.0 Z-25.0 R5.0 Q2.0 F100. This drills a hole centered at (10,5) to depth -25.0 with 2.0 units per peck, retracting to R=5.0 between pecks.

Notes: G83 is widely supported on many CNC controllers (such as Fanuc, Haas, and Siemens) but syntax variations exist; some systems use G98/G99 to control return mode. In some controllers, the same result can be achieved by G81 with a separate peck parameter or by different canned cycles. Understanding controller-specific syntax is essential.