thinkyhead

G29 - Automatic Bed Leveling

1.0.0-beta planner Probes the bed at 3 or more points

Probes the bed at 3 or more points and enables bed leveling compensation. The exact procedure and method depends on the type of bed leveling chosen in Configuration.h:

  • AUTO_BED_LEVELING_3POINT probes 3 points and uses a matrix to compensate for bed tilt.
  • AUTO_BED_LEVELING_LINEAR also uses a tilt matrix but probes a grid and applies “least-squares.”
  • AUTO_BED_LEVELING_BILINEAR probes a grid and produces a mesh to adjust Z across the bed.
  • There is also a manual MESH_BED_LEVELING option for setups without a probe.

The printer must be homed with G28 before G29.

Usage

G29 [B<pos>] [D<flag>] [F<pos>] [L<pos>] [P<int>] [R<pos>] [S<rate>] [T<flag>] [V<1|2|3|4>] [X<int>] [Y<int>]

Argument Description
[B<pos>]

Set the back limit of the probing grid

[D<flag>]

Dry-Run mode. Just probe the grid but don’t update the bed leveling data

[F<pos>]

Set the front limit of the probing grid

[L<pos>]

Set the left limit of the probing grid

[P<int>]

Set the size of the grid that will be probed (P x P points)

[R<pos>]

Set the right limit of the probing grid

[S<rate>]

Set the XY travel speed between probe points

[T<flag>]

Generate a Bed Topology Report

[V<1|2|3|4>]

Set the verbose level

[X<int>]

Override the X-size of the grid that will be probed

[Y<int>]

Override the Y-size of the grid that will be probed

Notes

Any arguments left out of G29 will use the default values set in Configuration.h.

Examples

G29 is most commonly used without any arguments. This uses the parameters set in Configuration.h.

G29 ; execute ABL

Probe a 5x5 matrix:

G29 P5 ; 5x5 matrix

Probe a 4x8 matrix from X50 Y50 to X150 Y150, printing a full report:

G29 X4 Y8 L50 R150 F50 B150 T V4