Autoleveller not levelling?

[suspension]

Hi

I have a very strange problem with auto leveller.
My bed is not flat (and also the copper board), so I am using the auto leveller. The board size is 7cm X 6 cm. I have used 80 probe points.
There is a track that goes from one end to the other. When CNC is milling this track I can clearly see that at one end it mills it nicely but when it reaches the other end, gradually milling amount (depth) increases. My tracks are thin so this causes track to dis-appear as it mills across the board. I have followed all the instructions in the documentation.

I have checked for CNC backlash, but it seems ok. (may be -.001-.003 mm). The depth I uses is -0.03.

i have tried this around 10 times (with different depths in flatcam) but results are same.

Appreciate if some one could give some advice.

Thanks

[spidey4fun]

I had an issue that I didn't notice initially with the Z depth on the first touch off. If you are not within 1mm of the surface it will not zero. I changed the first touch off from -1 to -10 to ensure it zeros correctly.

G31 Z-10 F100 (Probe to a maximum of the specified probe height at the specified feed rate)

I also did this on the PFG initial scan. I didn't notice it wasn't touching the surface on touch off so this also created a false result as it just stored -0.998 for each touch off resulting in a deeper cut as the touch off before cutting was correctly performed.

I hope that makes sense.