17.4.4. A reversing of the self-cutting screws with direct and crosswise vents
Sometimes strongly rusted connections cannot be turned off by means of the screw-driver. After several unsuccessful attempts of vents it is rumpled and it becomes impossible to turn out the screw in the usual way.
1. If it is not possible to turn out the screw, take the suitable screw-driver and try to turn out it, striking the screw-driver handle with the hammer.
2. If the screw broke, drill its rest.
3. If it is not possible to turn out the screw by effort of hands, use an impact driver.