PURPOSE: To set a hook angle of a cutting edge shape by fixing a suspended plate to a bar-like member, and forming round holes at the plate so that the holes are observed from a flat lower surface or a reference surface of the member, thereby facilitating an inspection of a cutting link.

CONSTITUTION: A hook angle gauge 36 has a bar-like member 40. The member 40 is linear with sufficiently long length or at least a length corresponding to three cutting links 10 of a chain saw. A face plate 42 is fixed to one side edge of the member 40. Holes 14a to 14h are formed at the plate 42. The holes 14a to 14h are the same size to conform to a size of a specific file shaft 14. A bottom of the member 40 is brought into contact with a maximum point of the link, i.e., a cutting point 30. The bottom is a reference surface 38, and exposed with the holes 14a to 14h. A reference line 38 is positioned along a cutting corner. The specific cutting link is selected. The link is slid along the member 40, the plate 42 and the link, and any of the holes 14a to 14h is brought into coincidence with a side cutting edge 26. For example, in the case of inspecting the link 10a, it is brought into coincidence with the hole 14a, i.e., the display hole of the hook angle of 10°. The link 10b has a hook angle of about 25° to conform to the hole 14d. And, the link 10c has a hook angle of about 40° to conform to the hole 14g.