{"id":"gcode-g74","model_id":"G74","name":"LinuxCNC G74 Left-hand Tapping Cycle with Dwell","summary":"G74 is a LinuxCNC G-code cycle for left-hand tapping with a floating chuck. It moves the Z axis at the programmed feed rate to the Z position, stops the selected spindle, starts clockwise spindle rotation, dwells for P seconds, and feeds back to clear Z. The document states that G74 does not use synchronized motion.","study_notes":["The feed rate F is spindle speed multiplied by distance per revolution (thread pitch); the document gives S100 with 1.25 mm per revolution as F125.","The L word is used in incremental mode to repeat the cycle; the document refers to G81 for examples.","The G74 cycle uses preliminary and in-between motion from the canned cycle motion section."],"safety_notes":["Warning: G74 does not use synchronized motion.","Feed and speed overrides are disabled during the G74 cycle and restored after it finishes."],"sources":[{"url":"https://linuxcnc.org/docs/html/gcode/g-code.html#gcode:g74","title":"G-Codes","accessed":"2026-10-26"}],"verification":{"status":"source_checked","checked_at":"2026-10-26","values":19,"method":"llm_source_check"},"updated_at":"2026-10-26","type":"instruction","spec":{"language":"gcode","code":"G74","syntax":"G74 (X- Y- Z-) or (U- V- W-) R- L- P- $- F-","parameters":[{"name":"X"},{"name":"Y"},{"name":"Z"},{"name":"U"},{"name":"V"},{"name":"W"},{"name":"R","description":"Retract position along the Z axis."},{"name":"L","description":"Used in incremental mode; number of times to repeat the cycle. See G81 for examples."},{"name":"P","description":"Dwell time (seconds)."},{"name":"$","description":"Selected spindle."},{"name":"F","description":"Feed rate (spindle speed multiplied by distance traveled per revolution (thread pitch))."}],"dialect":"LinuxCNC","related":[],"standards":[]},"url":"https://machineschema.com/instruction/gcode-g74","license":"https://creativecommons.org/licenses/by/4.0/"}