2025–2026 · Final Year Capstone Project
CNC Machine with GSK980TDa Control System
PT ATMI Surakarta needed a way to produce PCB (Printed Circuit Board) traces in-house but lacked a dedicated CNC machine for the job. The company already owned a GSK980TDa CNC control system, originally designed for 2-axis lathe machines, but had no machine built around it for this purpose. As the final-year capstone project, I was tasked with designing and building a 2-axis CNC engraving machine using the existing GSK980TDa controller, adapting it to control an additional pneumatic Z-axis, without procuring any new control hardware. I mapped the controller's native Z-axis to function as a mechanical Y-axis, enabling true two-axis linear interpolation for X-Y motion. I integrated a pneumatic double-acting cylinder, controlled through the GSK980TDa's internal PLC via a 5/3 double-solenoid valve, to handle the vertical (marking) motion instead of a third CNC-controlled axis. I calculated and configured the Electronic Gear Ratio between the GSK980TDa and the Mitsubishi MR-J3-20A servo drivers to ensure the system translated G-code commands into precise physical movement, then validated the setup through repeated point-to-point positioning tests. The final system achieved a 1:1 correspondence between commanded and actual linear displacement (e.g., a 1 mm command produced exactly 1 mm of physical movement), with a measured repeatability of 0 mm across repeated trials on both the X and Y axes. The machine successfully executed multi-axis interpolated paths, including diagonal and combined X-Y motion, within a ±0.1 mm tolerance, validating the design as a viable foundation for future PCB-machining development at the company.
Key contributions
- 2-axis CNC motion with pneumatic Z-axis
- Full mechanical, electrical, and pneumatic system design
- GSK980TDa controller with Mitsubishi servo integration