klipper-dgus/docs/Probe_Calibrate.md

This document describes the method for calibrating the x, y, and z offsets of an "automatic z probe" in Klipper. This is useful for users that have a [probe] or [bltouch] section in their config file.

Calibrating probe X and Y offsets

To calibrate the X and Y offset, navigate to the OctoPrint "Control" tab, home the printer, and then use the OctoPrint jogging buttons to move the head to a position near the center of the bed.

Place a piece of blue painters tape (or similar) on the bed underneath the probe. Navigate to the OctoPrint "Terminal" tab and issue a PROBE command:

PROBE

Place a mark on the tape directly under where the probe is (or use a similar method to note the location on the bed).

Issue a GET_POSITION command and record the toolhead XY location reported by that command. For example if one sees:

Recv: // toolhead: X:46.500000 Y:27.000000 Z:15.000000 E:0.000000

then one would record a probe X position of 46.5 and probe Y position of 27.

After recording the probe position, issue a series of G1 commands until the nozzle is directly above the mark on the bed. For example, one might issue:

G1 F300 X57 Y30 Z15

to move the nozzle to an X position of 57 and Y of 30. Once one finds the position directly above the mark, use the GET_POSITION command to report that position. This is the nozzle position.

The x_offset is then the nozzle_x_position - probe_x_position and y_offset is similarly the nozzle_y_position - probe_y_position. Update the printer.cfg file with the given values, remove the tape/marks from the bed, and then issue a RESTART command so that the new values take effect.

Calibrating probe Z offset

Providing an accurate probe Z offset is critical to obtaining high quality prints.

Start by homing the printer and then move the head to a position near the center of the bed. Navigate to the OctoPrint terminal tab and run the PROBE_CALIBRATE command to start Klipper's probe calibration tool.

This tool will perform an automatic probe, then lift the head, move the nozzle over the location of the probe point, and start the manual probe tool. Once the manual probe tool starts, perform the "paper test" to determine the actual nozzle height at the given point.

If the nozzle does not move to a position above the probe point, then ABORT the manual probe tool and perform the XY probe offset calibration described above.

After completing the "paper test", use the ACCEPT command to accept the current Z height and then use the SAVE_CONFIG command to save the given probe z_offset to the config file.