Adaptation of CNC milling machine for PCB etching

• Main Authors: Arellano, Paul Adrian, Bavar, Dan Errol, Guerrero, Miguel Antonio, Lagmay, Carlo Rey
• Format: text
• Language: English
• Published: Animo Repository 2008
• Subjects: Printed circuits > Design and construction; Machine-tools > Numerical control > Programming; Etching
• Online Access: https://animorepository.dlsu.edu.ph/etd_bachelors/14608
• Institution: De La Salle University

The conventional process of etching the copper tracks on a Printed Circuit Board (PCB) is through chemical etching. This is also the method employed by the Manufacturing Engineering and Management (MEM) Department of De La Salle University (DLSU) in fabricating their PCBs. However, chemical etching poses some risks to the health and the environment. The proponents of the group tried to find an alternative process to chemical etching and they employed the use of a Computer Numerically Controlled (CNC) Machine in order to handle the etching together with the drilling processes of a double-sided PCB. The group worked with a 1996-made Denford Triac VMC as their CNC Machine. The group accomplished this objective by first designing and fabricating a jig that can be attached to a CNC Machine and which will constrain the PCB while it is either being etched or drilled. Next, a software application named PCB Etchmaster was programmed by the group in order to convert the Gerber files produced by a PCB design program (Protel 99 SE) into G-Codes that would control the movements of the CNC Machine. Experiments were done to test the reliability and output of the system that was created. Different parameters were tested for this purpose such as accuracy of the design, depth of the cuts produced, electrical connectivity of the tracks milled, and alignment of the top and bottom layers of the double-sided board. Repeated trials and different PCB designs were made until the final desired output was reached. In the end, all tests confirmed that the system was robust enough to handle and satisfy the objectives of the study.