This is a horizontal dimension target for the Rostock MAX, built using OpenSCAD. I used it to calibrate the X and Y axes (not X and Y towers) of my Rostock MAX. The square holes are all 20mmx20mm, and the dividers between the holes are 5mm; the thickness is only 0.5mm (to avoid wasting plastic). So, in theory, the distance from the +X to -X ends, or the +Y to -Y ends, is 230mm. In practice, the walls tend to end up wider than that, so the holes end up smaller than that.

If you want to make changes to the dimensions: 1) Download the "Grid Test.scad" file, and open in OpenSCAD 2) In the calibrator module, edit the radius (e.g. for a smaller printer), the thickness (if you want to see what the dimensions are after they are no longer affected by the bed surface), and the hole and space dimensions (in mm) 3) Compile and Render to see the results 4) Save as a *.stl file If you just want to print the darn thing: 5) Download the Grid Test.stl file 6) Load it into your printer 7) Print it!

Attribution - Creative Commons

calibration, grid