Abstract
There are two main methods to attach the colorful patterns to the free form surface of 3C products at present time, one is IMD and the other is screen-printing. Because of the cost on molding and plate-making, both methods are only suitable for the mass production. In this study, software is firstly used to do 3D modeling, after that the pattern is applied on the 3D model and then plans the printing paths by using mapping transformation. The pre-process of the printing can be finished on computer. The hardware is based on the 5-axis CNC machine; the spindle of the 5-axis CNC machine is replaced by a commercial printer and uses the software of the printer to print the pattern. Furthermore, since the distance between the print head and curved surface is not a constant, it is necessary to maintain the distance in an optimal range. The width of pattern print head can print at a time is limited by the curvature of the printing surface. If the curvature of surface is too big, the print head should print only at the region which can print out a good printing quality. The rest unprinted area is printed after rotating the print head a proper angle. Since print head and surface model are substitute for the tool and work piece, so it is necessary to design the fixture to fix the print head and curved surface model. Moreover, how to synchronize the print signal and 5-axis machine is also important. As mentioned above, this study hopes to achieve printing colorful patterns on the 3D free form surface.