Just got my XXL built and playing around to get familiar with things. Im jogging it around ect… two problems. With XY positioning the center position is center front and center back is center… same on the left and right… No left or right back… and second with my z… it’s like it not picking up the limit switch and grinding… thanks for your future help… Jack
To troubleshoot the homing switch, please see: http://docs.carbide3d.com/software-faq/home-switch-troubleshooting/
For the machine positioning please see: https://www.shapeoko.com/wiki/index.php/SO3_Function_Test#XL — the balance of that page may be helpful as well.