G34 - Mechanical Gantry Calibration

2.0.4 calibration Modern replacement for Průša's TMC_Z_CALIBRATION MECHANICAL_GANTRY_CALIBRATION


This command is used to align the ends of the X gantry. See the video demonstration below.

  • The carriage moves to GANTRY_CALIBRATION_SAFE_POSITION, also called the “pounce” position.
  • If possible, the Z stepper current is reduced to the value specified by S (or GANTRY_CALIBRATION_CURRENT) to prevent damage to steppers and other parts. The reduced current should be just high enough to move the Z axis when not blocked.
  • The Z axis is jogged past the Z limit, only as far as the specified Z distance (or GANTRY_CALIBRATION_EXTRA_HEIGHT) at the GANTRY_CALIBRATION_FEEDRATE.
  • The Z axis is moved back to the working area (also at GANTRY_CALIBRATION_FEEDRATE).
  • Stepper current is restored back to normal.
  • Finally the machine is re-homed, according to GANTRY_CALIBRATION_COMMANDS_POST.


G34 [S<mA>] [Z<linear>]



Current value to use for the raise move. (Default: GANTRY_CALIBRATION_CURRENT)


    Extra distance past Z_MAX_POS to move the Z axis. (Default: GANTRY_CALIBRATION_EXTRA_HEIGHT)

      Related Media


      Mechanical gantry calibration: