Cal Part

A 40 x 40 x 10 mm cal part. It has X -> on the top. So alighn that with the X axis and then print. After its cooled you can remove and mesure with calipers. Then ajust the steps per mm. The X means you dont have to remember to mark it with a pen befor you remove it.

Scale up if you want a bigger test pice.

Simples.