Unresolved Bed leveling problem

Manual leveling is still the best way to get the best prints.

Auto Bed Leveling (ABL) in Marlin is not a perfect solution since it samples 8 points and then mathematically builds a level plane that intersects all 9 points and that is the 'level' plane it corrects to across the bed. (MESH leveling in the new versions of Marlin are a superior solution, but this is not enabled in the versions of Marlin that Robo provides. You look over the threads @WheresWaldo has on this if you are interested in upgrading yourself).

Here is one of Toms videos on this. It is not specific to Robo (but bed leveling is not specific to Robo). You can pretty easily transfer the ideas he is showing you into how they work on our printer. If not then we can help you address specific questions. Ultimately you shim the bed to level it. You can do this below the build plate frame (under the bearing holders that the bed rods move through) or above the build plate frame (between the glass bed and the frame).

 

With the original beta manual leveling was your only option so those of us who started with that model got good at it (or got rid of the printer)