Bollard Light,Outdoor Bollard Lights,Bollard Lamp,Garden Bollard Lights Ningbo Royalux Lighting Co., Ltd. , https://www.royaluxlite.com In the process of manufacturing sanding powder extruder, our factory encountered a difficult-to-machine part, namely a large-tapered trapezoidal spiral (Fig. 1). It is required to process the trapezoidal embossing while processing the taper. In the absence of a special machine tool, we use the template and the lead screw to cooperate with each other on the C620-1 ordinary lathe to make the middle carriage move obliquely, thus simultaneously completing the cutting process of taper and thread. Figure 2 shows the turning of the cone tool by the template.