How CNC works and when to use it
The CNC machine is operated by an onboard controller that runs three or more stepper motors and the toolhead. Stepper motors have a lot more torque and can be controlled with greater precision than ordinary electric motors. Motor control is measured in fractions of revolutions, which allows for excellent precision in movement. Using precision leadscrews (or pulley/belt systems), the motors move a gantry along the Y axis while the toolhead moves left and right on the gantry (the X axis). The Z axis is nothing more than a small gantry that moves the toolhead up and down, typically with a leadscrew.
The commands being passed to the controller on the CNC machine are called G-code. The commands passed to the controller (either via the onboard software or a computer passing G-code to the controller) move the toolhead to various locations in all three axes and runs the spindle motor so that the milling end can then cut into the material as desired. The...