Abstract: According to the actual manufacturing process of twist drill,the method of generating the rake face by using UG software to replace the helical groove truncation in the plane of helix method of twist drill was introduced.Based on the principle of conical grinding method,and the mathematical model analyzing of the flank face of twist drill,the main cutting edge and transverse edge of twist drill were determined with a two-way natural intersecting method,the twist drill flank face was established by using UG software,and the three-dimensional modeling of twist drill was completed.This modeling method can not only generate more realistic three-dimensional model of twist drill,but also effectively avoid the errors caused by artificial selection of the main cutting edge,which is of great significance for the subsequent analysis of the performance of twist drill.

Key words: twist drill, UG software, mathematical mode, 3D modeling