ASTM C 1047

This specification covers accessories used in conjunction with assemblies of gypsum wallboard and gypsum veneer base to protect edges and corners and to provide architectural features. Steel accessories and steel components of accessories manufactured from steel and paper in combination shall be manufactured from zinc-coated cold-roll sheet steel before application of coating. Phosphatizing or other surface treatments may be used to ensure compatibility and bond. Paper components of accessories manufactured from steel and paper in combination shall comply with requirements for thickness, tensile strength, dimensional stability, and bond of joint tape to joint compound. Accessories shall be free of twist or camber of a degree that will prevent their use in the assembly for which they are intended. Edges of accessories shall be free of burrs and sharp edges.