The coordinates being shown is your work coordinates (stock). When you home, you are setting your machine coordinates. So, based on the picture, you work origin is X-198 Y-206 Z2 from your home position.
Grbl Wiki> Nice writeup here: Why is Grbl in all negative coordinates after homing? Or it so annoying and not what I'm used to! Homing sets MPOS (Machine Coords / G53) G10 Pxx commands set the ZERO (what you are looking for) - which are offset away from MPOS If these are hard to understand, grab OpenBuilds CONTROL from OpenBuilds Software where we hide away all the complicated Coordinate Systems stuff. Jog to where you want 0,0,0 to be and hit the big SETZERO button
yeah, forget the negative numbers. jog to where you need the work o,o,o origin to be, hit the 'set zero' buttons and cut your job. assuming your work origin in bottom left corner then all the gcode will be positive except Z, Z going negative will indicate it is cutting material. (more detail: XY zero is at bottom left, Z zero is at the top of the material). if you make your work origin in the middle of the part (in your CAD/CAM software) then some of hte Gcode will be negative and some positive. so what? doesn't matter, GRBL will do the right thing so long as you set the work 0,0,0 at the right place on the raw material. you never need to think about the negative machine coordinates because you can just jog to where you need to be and set Work zeros.
