Here's a calibration tester that tests overhangs with the 43 degree angle ellipse, filament retraction with the 2 small circular pillars, X & Y accuracy with the triangle and sharp corners and curves. It also tests for warping. Use this with your print settings for the plastic being used to fine tune your 3D printer! Note: I would suggest scaling the size down if you want to print this relatively quickly; it took around 1 hour to print this calibration tester. I used a MakerGear M2 to print this calibration test. Here are the settings I used: Settings: 1.7mm layer height 100% speed for the cooling fan Use Raft & Skirt 53% Infill NO Support material 4500 mm/min print speed