bore — Boring / helical-bore cycleMachining cycles

Bore a hole — straight or helical milled.

bore at (x,y)… depth <d> [dia <D>] [pitch <p>] …

Equivalents: Fanuc G85/G86/G89 · Siemens CYCLE85–89

ParameterTypeDefault
atmmhole positions
depthmmbore depth
diammbore diameter (helical mill)
pitchmm/revhelical descent per revolution

Bore a hole to size. Straight boring feeds to depth and retracts (`G85`/`G86`/`G89` variants). Give a `dia` larger than the tool and it becomes a **helical interlock** — the cutter descends on a helix to mill out the full diameter, so one end mill bores a range of sizes (no dedicated boring bar). `pitch` sets the helical descent per revolution; `stepover`/`finish` control roughing passes and a finish allowance. Ahead of the basic vendor bore cycles. ``` straight bore helical bore (dia > tool) │ feed ▼ ╲ ╱ ╲ ╱ descends on a helix, │ ╳ ╳ milling the full bore Ø ▼ depth ╱ ╲ ╱ ╲ ```

helical-mill a 30 mm bore
units mm
tool 1 = endmill(dia=10)
spindle 4000
defaults { feed 400 }
bore at (0,0) depth 10 dia 30 pitch 1.5 stepover 3 finish 0.3

See also: drill · g2

← all commands