Cutting Tool Evolution

Being productive while maintaining consistency is paramount for success in manufacturing, but process variables related to the various manufacturing technologies in use — such as machines, material, part geometry and cutting tools — often seem to throw a wrench into metalworking success. When you think about cutting tools and all the process variables that come into play (machine, material, material hardness, part fixturing, type of toolholder, gauge lengths, cutting parameters, etc.), it’s of no surprise that a large percentage of cutting tools put into use are misapplied and/or underutilized. This is where interchangeable, indexable and a combination of the two (interchangeable- indexable) cutting tool systems can be applied. Engineered to be versatile, efficient and repeatable, these highly adaptable cutting tool systems offer powerful solutions for taking on manufacturing’s most persistent challenge — dealing with process variables.

This article will outline the difference between interchangeable and indexable cutting tools, and how these once mutually exclusive systems have been combined (e.g., interchangeable- indexable) to offer the advantages of indexable insert tooling and provide maximum customization and optimization towards various machining processes.

To set the stage, let’s start with basic definitions of indexable and interchangeable tool types, which are often confused with one another, so that readers can delineate between the two.

Indexable Cutting Tool: A cutting tool consisting of a body (typically made of steel) that incorporates mechanically clamped replaceable inserts (made of cemented carbide, ceramic, etc.) that can be rotated/ flipped multiple times or swapped as needed.

Interchangeable Cutting Tool: A cutting tool consisting of a holder/ body (steel, carbide, heavy metal) and interchangeable head attached to the shank with various, sometimes proprietary, methods (e.g., threaded connection, mechanical clamping, self-tightening mechanical pocket).

Indexable Insert Trends

Coatings & Materials: Coating enhancements are a consistent pursuit and continue to provide nice gains in productivity, especially for those companies that haven’t pursued pursued any improvements in a few years.

Substrate enhancements and more exotic insert materials such as ceramics and CBN/PCD inserts with chip formers are becoming more prevalent and improving productivity of difficult to machine materials/ applications, such as machining nickel-based super alloys (Inconel) and heat-treated (hardened) materials.

Higher Precision/Repeatability: Modern powder compaction presses provide extremely tight tolerances and precise control of the pressing cycle. This control in the first phase of insert creation leads to a higher performance on the machine.