Characterization of drill bit breakage in PCB drilling process based on high-speed video analysis

Purpose - The purposes of this paper are to study the characterization of drill bit breakage in printed circuit board (PCB) drilling process based on high-speed video analysis and to provide an important reference for micro drill bit breakage prediction. Design/methodology/approach - Based on PCB drilling experiment, the high-speed camera was used to observe the micro drill breakage process and the chip removal process. The variation of chip in the drilling process was studied and one of the key reasons for the drill bit breakage was analysed. Finally, the swing angles' feature during the breakage process of the micro drill was analysed and researched with the image processing tools of MATLAB. Findings - The micro drill was prone to breakage mainly because of the blocked chips. The breakage process of the micro drill can be divided into the stage of stable chips evacuation, the stage of blocked chips and the stage of drill bit breakage. The radians of swing angles were basically in the range of +/- 0.01 when the drilling possess is normal. But when the radians of swing angles considerably exceeded the range of +/- 0.01, the micro drill bit may be fractured. Originality/value - This paper presented the method to study the characterization of drill bit breakage in the PCB drilling process by using highspeed video analysis technology. Meanwhile, an effective suggestion about monitoring the radians of swing angles to predict the breakage of micro drill bit was also provided.