The wings rubbing the wood and prevent that it forced to feed. At the impact of the blades: Drilling Screws on the metal breaking the blade. Even in the balcony construction will make these screws are used a lot in the wooden board on a steel substructure to screw. But also for attaching panel materials in design construction come planetary drill often has been used. Practical when in use on planetary drill is the use of strong battery wrench to drill with enough speed and power).