Infinity Bed Flatness Test

I made this to see if my printer bed was flat. This is 0.2mm thick with 0.4mm wide lines. This thickness was the lowest I wanted to test for my Da Vinci 1.0. The width of the lines was the lowest that the slicing software would detect reliably (it takes a lot longer for the slicer to solve this than you would think, 8 minutes plus for me).

It can take an hour or so to print, but it does look cool once done, almost like a tunnel going off into infinity (thus the name).

I was able to determine my print bed is slightly convex, or maybe the printer head dips down in the center due to weak support. Either way it also shows if your bed is level with the print head.