The chamfer of the worm is 40 degrees.
The worm refers to a gear that has one or several helical teeth and meshes with the worm gear to form a staggered shaft gear pair. The indexing surface can be a cylindrical surface, a conical surface or a torus surface, and there are four categories: Archimedean worm, involute worm, normal straight profile worm, and cone-enveloped cylindrical worm.