Abstract: To machine the various irregular residual areas left by pocket roughing,a spiral looping toolpath pattern is proposed and its generation method is established.Firstly,a concept of the generalized corner residual area(GCRA) is defined to represent residual corners and bottleneck areas uniformly.Secondly,according to bottleneck lines,the residual bottleneck area is subdivided to construct GCRA.Thirdly,an iterative method is adopted to generate the spiral looping tool-path based on the radial depth.Finally,an example is illustrated to validate that the proposed tool-path is available and effective.