Scabbling is a mechanical process of removing a thin layer of concrete from a structure, typically achieved by compressed air powered machines called scabblers, planers, groovers or scarifiers. These machines use several heads, each with several carbide or steel tips that peck at the concrete. Scabbling is the most widely recognised method of preparing a surface in modern construction.
Typically, scabbling is carried out with pneumatic devices that pound the surface with pointed rods. However, rotary devices that ‘flail’ the surface may also be used. The ‘flailing’ action is achieved by the loose fitting of multi-point circular cutters across a cylindrical drum. These machines then hammer and scratch the wall or floor to reduce the level of concrete or screeds, as well as removing the stubborn deposits that can often be found on industrial and commercial walls and floors.
There are several reasons that scabbling is a desired process. Scabbling helps to reduce screeds and levels in a surface and remove unwanted coatings and markings to prepare a surface for painting and coating. Scrabbling can also help to roughen, texture and groove a surface to increase slip resistance, and to remove deposits on a surface such as ice in cold stores.