ate hardness and depth). For softer substrates such as wood or soft plastics, the self-tapping ability?can come simply from a tip that tapers to a gimlet point (in which no flute is needed). Like the tip of a nailor gimlet, such a point forms the hole by displacement of the surrounding material rather than any?chip-forming drilling/cutting/evacuating action.Some self-tapping screws are also self-drilling, which means?that, in addition to the tap-like flute in the leading threads, there is als