Summary

A simple, no frills calibration / stress test print.

Print without supports - 'cause that's the point :-)

Overall dimensions are 20mm wide x 40mm long x 30mm high.
The 2 vertical holes are 5 & 3 mm diameter each.
The 1/2 circle along the one side has a diameter of 10mm.
The bridge pillars are 5x5mm, the gap is 5mm and the beams are 5x5mm.
The large arch has a 36mm diameter.

The arch's test your overhangs, and the bridges test your bridging - aka your cooling.
The rest tests basic X/Y/Z calibration and extrusion.

On my machine, at 60mm/s it takes less than 30 minutes to print. At 30mm/s its about an hour.

Neither of my printer / slicer combinations can do it perfectly.

(Ideally the slicer would do perimeters from outside in, unless it detects an overhang > 45 degrees, then do inside out. If possible, never start printing a perimeter on an overhang. And also if possible, start any infill from someplace 'solid', not from the edge of an overhang.)

This thing was made with Tinkercad. Edit it online https://www.tinkercad.com/things/7TTKhkSmxit