This is a test object to determine real-world 3D printer resolution and behaviour when confronted with sub-resolution features. Units are millimeters. It consists of an array of otherwise uniform grids of decreasing wall thickness (2, 1, 0.75, 0.5, 0.4, 0.3, 0.25, 0.2, 0.15, 0.1, 0.05 and 0.01 mm). I have also included the Art of Illusion script I wrote to generate the grids, in case you want to vary the grid size, wall thickness, periodicity etc.

Print and examine, try printing at different angles and choice of Z-axis to see if that makes a difference. On one of the newer Stratasys machines, the grid started to get a bit irregular at the 0.5 mm grid, and did not get much thinner below that (appears to only print double-wall structures even when a single fillet would be more appropriate, perhaps there is a setting I could use to change this?), and the 0.01 mm grid is printed as a solid sheet with no holes in it for reasons that are unclear. May also be useful on other machines (e.g. I intend to try a version on a laser cutter when I get access).