About this 3D model

I made these files to verify my 3D printer built accurate part geometry regardless of part orientation. There's a series of star-shaped shafts at various angles, and a series of disks with star-shaped openings that should fit over any of the shafts in all 8 rotations. A recent comment by Tony Buser (http://www.thingiverse.com/derivative:21136) got me thinking that this might be an instructive test for hobby printers, too.