I have a RAMPS1.4 running Marlin-MPCNC_Ramps_T8_16T_LCD_32step_DualEndstop
I uncommented the manual mesh bed leveling and set it to a grid of 4x4
However I get a jump of about 5 mmm in z height 3 quarters along the y axis, at every point across the x axis, coming back in drops down.
I’ve played with using the g29 s3 to make a mesh
test 1. 4x4 grid
high (8mm) Y to low (0mm) Y
test 2. 4x4 grid
high (8mm) X to low (0mm) X
both work with smooth transitions.
However with my correct mesh loaded and the maximum different only 2mm it jumps.
So I have marlin-bugfix.2.x installed and working on my SKR1.3 with dual end stops.
However bed leveling will not work on my 2440x1220 bed size.
If the bed size is 600x600 then my mesh (would) work. however when the bed is configured with the correct 2440x1220 and the mesh loaded. at about 900mm the z axis jumps up, and down on the return.