Test Square 160 x 160 1mm

thingiverse

This is a simple test square, it should print centre of bed, so you can tell if you extruder or bed is lined up correctly and prints out straight, when it has printed you can just measure from the edge of the print to the edge of you bed so lets you see if its centre. its prints a square 160mm x 160mm x 1mm thick, so you should have an even measurement from each side to the edge of the bed, and lets you measure the thickness to help with calibration etc.