Method and apparatus for producing characters on a grit-erodible body

摘要

A method and apparatus for producing characters on a surface of a grit-erodible body are provided. A negative of the characters is first produced, usually photographically. Ultraviolet light is then directed through the negative onto a blasting mask blank comprising a backing sheet and a uniform layer of polymerizable material thereon. Light struck portions of the layer harden and the rest is washed away to produce the characters, and specifically a font of type. Selected characters are then positioned backward on a transfer sheet and transported to the surface of the body of grit-erodible material to which they are adhered, with the transfer sheet then peeled away. Blasting grit is then directed toward the surface to erode the grit-erodible material around the characters to a desired depth.