Why can't I punch holes in the ceiling?
You should be the hammer, drill and punching machine. If the drill is black, you may see a galvanized iron pipe (Chuan Xianguan) or a steel bar, please do not hit it. Change the position and drill again.
When the bore diameter is below 25mm, the impact drill is used to reduce the damage around the hole. The aperture with a hammer in above 25mm, has the advantages of no need of hand so much effort, in concrete structures, brick, stone and other hard materials (except metal) on 6--100mm hole.
The hammer or hammer drills.Hammer and impact drill has piston movement function, can be in the concrete structures on the hole, but the ratio of power electric impact drill, according to the size and depth of the hole to decide what.
