He’s eschewed a router or extruder, and instead fit an off-the-shelf CNC machine kit with a sandblaster ... an STM32F469 discovery board and an Arduino CNC shield. He has a G-code controller ...

This familiar footprint manages to contain everything you need for a three-axis machine. The purple boards slotted into the pairs of SIL headers are Pololu Stepper motor drivers. Going this route ...