Method of manufacturing an endmill tool

Disclosed is a method of manufacturing an endmill tool, including detecting a crystal direction of a selected natural diamond gemstone (1) by inspecting the structure of the diamond gemstone (S100), forming a lower base surface (S20) and an upper reference surface (S230) of the diamond gemstone by using abrading equipment after welding the diamond gemstone with a first sub-body (20a, 20b, 20c), grinding (S300) an edge portion of the diamond gemstone by using grinding equipment after welding a machining tip, which is separated from the first sub-body (20a, 20b, 20c), with a second sub-body (30) to complete the machining tip having a cutting blade, and temporarily installing (S400) the machining tip, which is separated from the second sub-body, in a super hard body installed in setting equipment, adjusting an alignment state of the machining tip, and bonding the machining tip with the super hard body by using a normal-temperature bonding agent through a normal-temperature coagulation scheme to complete the endmill tool.