DEVELOPMENT OF A COMPUTER NUMERICAL CONTROL (CNC) PLOTTER USING ARDUINO UNO

This project presents the design and implementation of a compact and low-cost Computer Numerical Control (CNC) plotter tailored for rapid and precise printed circuit board (PCB) prototyping. This was achieved by interpreting standard G-code commands using Arduino Uno. The interpreted commands were used to drive an end-effector (a permanent etch-resistant marker) across an XYZ gantry within its defined work envelope, enabling the direct plotting of circuit patterns onto copper-clad boards. This automated approach replaces manual tracing and toner-transfer techniques, offering improved accuracy, repeatability, and usability for students, hobbyists, and research laboratories. The development process involved designing and fabricating a lightweight yet rigid chassis using precision-cut MDF components, integrating stepper-motor-driven linear motion with limit-switch calibration, and employing an Arduino Uno microcontroller running open-source GRBL firmware to convert G-code into precise motor control signals. A servo mechanism was implemented for Z-axis tool actuation, allowing reliable pen-up and pen-down movements during plotting. Validation experiments demonstrated plotting accuracy within ±0.2 mm, with percentage errors less than 2.5%. Repeatability tests confirmed consistent outputs across multiple runs; also, the total fabrication cost of the prototype was significantly lower than most commercial mini-CNC plotters. These results confirm the viability of the system as an accessible and cost-effective platform for rapid PCB development. Furthermore, the prototype provides a scalable foundation for future enhancements such as multi-layer support, automated tool changes, and integration with additional manufacturing processes.