How big expansion screw does the 6mm bit have?
6mm drills are generally equipped with 5mm expansion screws (the smallest specification).The relationship between the drill bit and the expansion screw is the drill diameter = the expansion screw diameter +2mm. For example, the expansion screw of 6mm shall be opened with 8mm drill bit.
Expansion screw generally refers to the metal expansion screws, expansion screws fixed, but the use of wedge slope to promote expansion, friction, grip force, to achieve fixed effect. One end of the screw is threaded, and the other has taper. Outside the bread (some tin pipe), iron cylinder (steel tube) has several half incision, put them together into the wall lay the hole, then the lock nut, the nut screw pull, pull cylinder taper iron, iron cylinder is open up, so tightly fixed on the wall, generally used for protection bar, awning, air conditioning and other fastening in the cement, bricks and other materials. But its fixed is not very reliable, if the load has a larger vibration, may be loose, so it is not recommended for the installation of ceiling fans.
