Marlin 2 Bilinear Auto Bed Leveling

Hi Guys.

I'm strugling with the bilinear Bed Leveling on my DIY Printer.

So in Marlin it says:

 * - AUTO_BED_LEVELING_BILINEAR
 *   Probe several points in a grid.
 *   You specify the rectangle and the density of sample points.
 *   The result is a mesh, best for large or uneven beds.

Probe several points in a grid.
is obviously adjusted by these 2 parameters:
#define GRID_MAX_POINTS_X 4
#define GRID_MAX_POINTS_Y 3

but where do I specify the rectangle and the density of sample points? I remember in v1 there were the parameters LEFT_PROBE_BED_POSITION, RIGHT_PROBE_BED_POSITION, FRONT_PROBE_BED_POSITION, BACK_PROBE_BED_POSITION. But I cant find these in v2. I've also setted the NOZZLE_TO_PROBE_OFFSET, which is correct in my opinion, but the printer always tries to probe outside the bed the last 4 points.

#define NOZZLE_TO_PROBE_OFFSET { 16, 33, 1 }

When I'm in front of the Printer the Z-Probe is behind and left to the nozzle so the values are positive (?).


Hope someone can help

best regards

See the diagram in the config

* Assuming the typical work area orientation:
 *  - Probe to RIGHT of the Nozzle has a Positive X offset
 *  - Probe to LEFT  of the Nozzle has a Negative X offset
 *  - Probe in BACK  of the Nozzle has a Positive Y offset
 *  - Probe in FRONT of the Nozzle has a Negative Y offset
 *
 * Some examples:
 *   #define NOZZLE_TO_PROBE_OFFSET { 10, 10, -1 }   // Example "1"
 *   #define NOZZLE_TO_PROBE_OFFSET {-10,  5, -1 }   // Example "2"
 *   #define NOZZLE_TO_PROBE_OFFSET {  5, -5, -1 }   // Example "3"
 *   #define NOZZLE_TO_PROBE_OFFSET {-15,-10, -1 }   // Example "4"
 *
 *     +-- BACK ---+
 *     |    [+]    |
 *   L |        1  | R <-- Example "1" (right+,  back+)
 *   E |  2        | I <-- Example "2" ( left-,  back+)
 *   F |[-]  N  [+]| G <-- Nozzle
 *   T |       3   | H <-- Example "3" (right+, front-)
 *     | 4         | T <-- Example "4" ( left-, front-)
 *     |    [-]    |
 *     O-- FRONT --+
 */

This diagram presumes your X0,Y0 is standard front left. of the bed. (ie the O meaning origin point)

"#define NOZZLE_TO_PROBE_OFFSET { 16, 33, 1 }"
"When I'm in front of the Printer the Z-Probe is behind and left to the nozzle so the values are positive (?)."

Yes and no, one of each

Presuming your measurements are correct

left of nozzle is - ie -16
behind the nozzle is positive ie 33

Also your Z value says your probe point is higher than your hotend by 1mm, so to probe you dig the hotend into the bed by 1mm...

Edited 1 time(s). Last edit at 03/26/2024 03:32AM by Dust.