Tool for centering milling machine on hole

It is tricky to center a milling machine on a hole of a part to be machined. This small cone that can be fixed on a chuck of the turret can be helpful.

Descend the turret until the cone is adjusted in the hole where the milling machine needs to be centered, in taking care not to fix strongly the part to be machined. When the turret is down and the part can only move around it axes, just fix it, and do not forgot to adjust coordinates in CNC controller.