3D Printer Bed Leveller

Getting a 3D printer bed level is critical for producing decent printed objects. I found that the 4 screws of my FF Creator combined with a sheet of paper couldn't get me near to the accurate position I wanted, so I designed this object.

To use, start by leveling the build plate as near as possible using the mechanical raise/lower screws. Then run this print. If you are using Simplify3D then turn on the skirt option, as that helps. With Simplify3D you can also define to stop printing at a giv