A novel approach for plunging using plungers of predefined geometry

Plunge milling is a very efficient roughing process. Optimizing the tool path of the plungers will enhance the plunge process. A novel approach is developed and introduced in this paper to optimize the tool path of the plungers using plungers of predefined geometry. For this purpose, maximizing the covered plunging area and minimizing the number of the plunging cycles are required. Unlike the current methods that demand specific geometry for the plungers, the proposed approach starts from predefined geometry for these plungers according to the availability in the market; eliminating the constrains imposed by the current methods. The developed approach combines two basic approaches, namely: The medial axis transformation approach and the offset techniques approach in order to generate data points within the contour of the required shape. Data points are then studied for possible selection to ensure an optimal plunging process. The developed approach is validated by simulation and compared with previous work, its superiority over the current methods is confirmed through many case studies. For instance, a flower shape with a multi-regions contour and the human hand shape with some narrow and complicated regions. The studied case studies revealed the possibility of reducing the number of plungers used and increasing the plunging area. The effectiveness of the approach for narrow shapes and its orientation-independence is obvious in comparison with the current methods; qualitatively through figures and quantitatively by reduce the number of plungers to 37 instead of 72, and the plunging ration is improved to 92.3, surpassing the previous method’s ratio of 72.26 as shown in Table 2. The last comparison includes a complex pocket with island, our findings indicate an improvement over the previous method in two key aspects: reducing the number of tools and expanding the covered area.