The effect of drilling speed and the chip load on the hole quality in
a printed circuit board was investigated. The hole defects considered
were smear, burr, nail heading and void Holes drilled with different c
ombinations of the speed and chip load were sectioned and examined usi
ng a scanning electron microscope to identify and quantify the defects
. Each defect was related to the drilling variables in order to explai
n the reason far its formation and discuss the broad trends in the rel
ationships.