Generation of Uniformly Aligned Dimples on a Curved Surface Using a Curved-Surface, Patch-Division Milling Technique

Many products are designed with surface textures that enhance the aesthetic and tactile qualities of the product. In this paper, a curved-surface, patch-division milling technique is proposed for creating uniform aligned cutter marks on a curved surface. Previous research demonstrated a ball-end milling technique that divides the surface into small planar patches where each patch is generated by a helical tool path with dimples in uniform alignment. Because the patches are planar, it is impossible to precisely machine a concave or convex surface. However, the technique could only approximate a method for machining curved surfaces. To resolve this issue, curved surface patches were developed to generate the patch directly according to the shape of the targeted curved surface. The dimples are expected to be uniformly aligned on curvedsurface patches. Therefore, the targeted surface should be cut using an appropriate machining condition. According to the test results, the distribution of dimples was the same as the pre-determined distribution. In addition, the dimples were regularly aligned when viewed from a specific angle. This proposed method overcomes the deviation of the dimple's positions, which is caused by the acceleration--deceleration of the machine tool and the change of the cutting point during five-axis machining.