The basic design for this part came from a definition used to place (stick on) panels on the outside facade of a building. I modified it to subtract rather than add objects to a 3D surface, and used hemispheres instead of flat panels to make the holes.  is my blog page describing how I've made 3D printer objects based on architectural designs.

This part printed in 24 1/4 hours using a layer height of 0.200 mm and a print speed of 100 mm/sec.