Questions with Tom Raun

1. For companies manufacturing medical components, what trends should they be aware of or implementing to improve machining processes?
One of the biggest opportunities is related to finish-milling applications of free-form (3D) components/surfaces by implementing circle segment programming and cutting tool technology. Fairly recent innovations from CAM and cutting tool suppliers have created the opportunity to leverage the circle segment approach.

2. What is a circle segment cutting tool?
A simple definition is a cutting tool designed with a large radius (i.e., part of a circle), on the nose and/or flutes of the tool, within a given distance/segment. Hence the name, circle segment.

3. Why should metalworking/machining operators pay attention to the circle segment milling approach?
Huge productivity gains! Early adopters of this approach report cycle time reductions up to 90% in some applications. Although these may be outliers, it’s not uncommon to realize cycle time reductions of 50% or more when applying the circle segment approach. It’s a simple concept/approach, but it wasn’t easy to implement due to constraints related to programming and cutting tool designs. During the past few years, it’s become easier for companies to implement the circle segment approach due to advancements in CAM technology/toolpaths and their ability to recognize/apply hybrid cutting tool designs. Circle segment cutting tools have been around for quite some time – think high-feed milling tools with a large radius on the nose/end – but the concept has been literally turned on its side to encompass more cutting tool designs such as the taper-shape barrel and oval-shape barrel, which are versatile in their application. It’s not uncommon for technologies in a related field to chase one another. In metalworking, the shift toward finish-milling applications with circle segment cutting tools is mainly due to CAM industry advancements and their ability to program (or drive) machine tools in a way they’ve been capable of for some time. It simply wasn’t easy, or even possible, to program. These developments have driven the cutting tool industry to think differently and design product lines to fit this ever-growing approach.

4. And this led ISCAR to introduce circle segment tooling in their popular Multi-Master system?
Yes, the Multi-Master system is a perfect solution for this milling approach. For example, if using a lens-type tool, the application will only use the nose (end) of the tool, so there’s no need to use a solid carbide tool. Why pay for and waste so much carbide when only the end of the tool will engage material (think underutilization)? The same logic applies to the circle segment approach using tapered-shape barrel or oval-shaped barrel cutting tools. Even though the steps between each milling pass are larger, there’s only so far one can go while maintaining surface finish requirements, making an interchangeable head solution the perfect fit for the circle segment approach.

Materials commonly used in manufacturing medical components can be difficult to machine (hard, abrasive, etc.). The circle segment milling approach will ultimately provide tool cost savings, due to taking fewer passes to complete components (less contact time). This is a perfect example of how improving cutting tool utilization provides huge gains in productivity.

FOR MORE INFO:
https://www.iscarusa.com