I builded a bigger cartesian Printer with a glasplate of 600x500mm and wanted to use autobed leveling (bilinear grid of 3 x 3 points) with a capacitive sensor on
a Rumba board.
The sensor reacts Right and I can home perfectly. The Problem is that everytime I run the G29 command the sensor is moved over a grid of 3x3 = 9 Points.
In the first 3 Points of the line the sensor detaches the glassurface around 1mm (z Offset is not adjusted yet) heigt, which is fine. In the second line I can see that the
sensor is reacting far more away from the glassurface ( so here are around 5-6mm) and in the last line the sensor is reacting as on line 1 with around 1-2 mm.
So first and third line can be Right because the bed will be not perfectly flat. The only Thing I don't understand is, why the sensor reacts in the middle of the bed
around 4-5 mm height differently from the Surface although physicalwise this is nearby like the 1 and 3 line?
For sure then like this I cannot Level the bed automaticly. Where do I Need to look in Marlin to overcome this fault?
any ideas?
