This is the test piece set I use to check accuracy of a 3D printer. With this set, you can check accuracy of perimeter, inside perimeter, thickness, angle, and plug-fit of differently sized shapes to understand behavior of your new printer (or printer configuration). Whole set only consumes ~1m of a filament, and will print in ~30min. Quick turnaround-time is a must-have when you are tuning printer configuration with trial-and-error. This is written in OpenSCAD script and it is easy to change size or number of pieces. I also might update it so it can be reconfigured on-line, using Thingiverse OpenSCAD parametarized model specification.