NEGATIVE-TYPE CUTTING INSERT, BLADE-INTERCHANGEABLE ROTARY CUTTING TOOL USING SAME CUTTING INSERT, BLADE-INTERCHANGEABLE ROTARY CUTTING TOOL SYSTEM, AND CUTTING METHOD

摘要

A negative cutting insert having a cutting edge comprising four long-side cutting edge portions for rough cutting and four short-side cutting edge portions for finish cutting, which are connected alternately, thereby being able to conduct rough cutting when attached to a rough-cutting tool body, and finish cutting when attached to a finish-cutting tool body. When such cutting inserts are used for rough or finish cutting and then reattached to a finish-cutting tool body or a rough-cutting tool body, finish or rough cutting can be conducted, thereby using all cutting edges thoroughly.