Based on the engagement principle of roller gear cam mechanism,the paper builds the cutter moving tracks equation of scroll cam for XK-5001 style double rotary coordinate numerically controlled special milling machine. It analyses how to get the cutter moving tracks. The scroll cam can be made by the numerically controlled programming. Batch processing shows that the product from this technology not only satisfies the needs of designing and using but also has higher economic feasibility and dependabilit...