Drill an electric hole first, and then press the screw on the inside of the thread. What's the name of the wire tool?
Such as the diameter of the screw with 4mm 3.2 bit, 4.5 bit 5mm, the use of wire tapping to the vertical fixed hand tapping, partial silk road is slanting, the screw is crooked, when tapping evenly, a semi circle and add a little oil, or will the screw break, see if can help you
Hand drill in metal, wood, plastic, and other materials (concrete, tile, borehole structure, sediment except) switch wire tool called silk attack, in order to use the plate on the screw hole, can choose the screw, drill (hole) diameter than the screw diameter is small, otherwise there is no space for tapping
