1. Field of the Invention
Embodiments of the present invention relate to the processing of metallic surfaces. More particularly, embodiments of the present invention relate to an apparatus to apply a lightly scratched finish to a metal surface and a method of construction of the apparatus.
2. Description of the Related Art
Exposed metal is often used as a wall surface, particularly on the exteriors of buildings, such as event centers, coliseums, or museums. It is usually desirable that the surface have a finish that scatters light to avoid harsh glares or strong reflection of the sun. Generally, a lightly scratched metal surface has a soft or matted appearance that is more aesthetically pleasing.
Prior art techniques to produce a lightly-scratched metallic surface have involved manual approaches as well as machine-controlled processes. With manual approaches, an operator may use a handheld sanding disc or a floor sander to apply scratches to the surface of the metal and must visually judge the level of scratching on the surface. Typically, some areas are more scratched than others, resulting in a surface that looks non-uniform.
Machine-controlled techniques may involve adapting a rotating sanding disc to a computer numerical controlled (CNC) machine. The sanding disc may be scanned across the metallic surface to apply scratches in a more uniform manner than manual approaches. However, the surface may include subtle lines where the scanning pattern overlaps that have a darker shading than other areas of the surface. Furthermore, the overlapped areas may appear to have large arc-shaped features under certain lighting. As a result, the machine-controlled approach may be less aesthetically pleasing due to subtle imperfections.