PURPOSE: To enable work to be executed as assembly lines and also to be conducted efficiently at the time of giving by a cutting process vertical and longitudinal brick or tile lined-joint patterns on the surface.

CONSTITUTION: The working method has a process in which when vertical and longitudinal uneven patterns are given on the surface of a panel body G such as ceramic plate materials, the panel body G is securely supported on a table 1, and the working table 1 is moved toward a first cutting device 2A for cut-forming parallel grooves on the surface of the panel body G, and after the completion of the process, the working table 1 is moved to the orthogonal direction with respect to the linear moving direction as the panel body G is fixedly supported and subsequently moved to a second cutting device 2B for cut-forming parallel grooves that intersect at right angels to the parallel grooves. After fixation onto the working table 1, all of the work can be done automatically.