Chipbreakers
Maximize uptime by controlling chips.
by David Wynn
Director of Technical Services, PMPA
Published May 1, 2025
In the world of machining, the selection and utilization of appropriate chipbreakers play a pivotal role in optimizing cutting processes. Chipbreakers are features integrated into cutting tools to control chip formation, breakage and evacuation during material removal. Effective chip management is crucial for enhancing cutting efficiency, improving surface finish and extending tool life.
The formation and management of chips are critical to having a stable process. Improper chip control can lead to several issues but the most important issue is machine downtime. Chipbreakers are designed to move the chip from the work area and create manageable chunks that can be evacuated from the machine. Proper management of chips is crucial to maximizing uptime.
There are several ways to break a chip. Many times, changes to machining parameters can break chips. Adjusting the feed and speed, creating peck cycles or utilizing the new features on some machines to create automated peck cycles while turning. (Think Citizen LFV, Tsugami Oscillation Cutting or Star HFT technology.) Some materials, no matter what techniques we utilize, still need help from tool geometry to break the chip. Chipbreakers will even vary by material because different properties require different geometry to break the chip. Copper alloys will need different geometry than high nickel alloys.
Types of Chipbreakers
Chipbreakers come in various designs, each tailored to specific machining requirements. Most manufacturers have proprietary chipbreakers, but I feel most fall into these primary types:
2 Dimensional (2D)
Examples include top grooves ground into a tool, grinding grooves along the drill margin to break chips, creation of raised back walls or reduced back walls on tools. All of these give room for the chip to flow away from the work and create a stress point to break the chip. Most 2D chipbreakers are simple types that we have learned how to grind into our tooling. Chipbreakers of this type were discovered through trial and error while cutting metal.
Simple 3 Dimensional (3D)
These types of chipbreakers are much more complex than traditional 2D styles. It takes precise manufacturing techniques to produce the more complex shape. Tools with simple 3D chipbreakers have been CNC ground or had the shapes pressed into them during manufacturing. Variable grooves, flowing rank angles, stepped geometries and more are precisely designed for specific purposes and materials.
Complex 3 Dimensional (3D)
Complex chipbreakers are formed by pressing raw inserts to create complex shapes such as dimples, finger grooves, wavy formations, chip channels along the insert cutting edge and more. New styles are being developed every day. The complex shapes have allowed insert manufacturers to tackle very specific machining problems. Advances in manufacturing have allowed insert manufacturers the ability to make higher mixes of shapes providing greater variety in choice of chipbreakers.
In conclusion, the selection and utilization of appropriate chipbreakers is integral to achieving efficient and effective machining processes. By understanding the importance of chip control and becoming familiar with different chipbreaker types, machinists can optimize cutting tool performance, increase uptime to improve tool life and enhance overall productivity.
Author
David Wynn is the PMPA Director of Technical Services with over 20 years of experience in the areas of manufacturing, quality, ownership, IT and economics. Email David