The Investigation of Thrust Force of Printed Circuit Board Drilling

This work is focused on the investigation of the influence of the materials of PCB, feed rate, spindle speed and tool wear on thrust force when drilling PCB using 0.3 mm diameter cemented tungsten carbide drills. The results indicate that thrust force increases with feed rate and drill wear, but decreases with spindle speed firstly and then increases with it within the cutting range tested. Thrust force caused by the copper foil is much larger than that caused by the epoxy glass fiber cloth when feed rate is low. However, the difference between them decreases as feed rate increases. The thickness of nail head increases with thrust force. The accuracy of hole location increases with thrust force firstly but decreases afterward. The influence of thrust force on hole wall roughness is not obvious.