CNC Milling Machine Axis Explained [Complete DIY Guide I ve laid out a process you can use to select the right ones in my in depth series on how to design the ultimate benchtop CNC milling machine Here s the chapter on ballscrews [ Ultimate Benchtop CNC Mini Mill Part 2 CNC Mechanicals] Motor Stepper motor for a CNC Milling Machine The photo above shows a typical Stepper Motor for a CNC Milling Machine Stepper Motors are called