This was a thing I printed out for a friend, it is some sort of test holder for their project but it turns out to be a really great printer exerciser as well. I've been looking at dimensional stability and this is an array of holes with feature incursion into the holes, on a 2.54mm grid. Designed in TurboCAD 20. The goal of printing it would be to see if your printer can print it. One of the things it challenges is the heated bed, keeping the sides warm enough between layers. I could not get it to print oriented with the long strips down on my Makerbot Replicator Dual. The image was this thing printed with black ABS, 240C on the nozzle, 112C on the Bed.