VIDEO: Fundamentals of Machining: What is CNC Turning?

Welcome to this edition of Seco Shop Talk. I’m Gary Meyers and in this episode I’m going to cover the basics of turning. Even if you have little or no knowledge about the manufacturing industry, you’ve probably heard the term machining. It’s a term used by manufacturing companies to convert raw materials by cutting and shaping them into finished parts. Think of aerospace landing gears, automotive axles, or small medical parts such as bone screws.

Now let’s go over the basics of turning. A very common question that I get when working with our customers is that they are still not clear with milling versus turning when it comes to manufacturing of parts. I simply take them to a place that they are more familiar with…the kitchen. You see, turning is like an apple peeler. The apple turns and the cutter is stationary. And when you’re milling, think of a kitchen mixer. The beater’s rotating and the bowl is stationary.

Along with milling, drilling, turning is a common machining process used in manufacturing. The term turning is used when referring to the machine processes that involve the workpiece being placed inside the machine and to strong, adjustable jaws where it rotates or turns, the workpiece. Allowing a stationary cutting tool to cut it to the desired shape just like the apple peeler.

Turning is performed in one of two ways. Manual turning or automatic turning, also known as CNC turning. Manual turning requires a worker to manually adjust the machine to get the desired results to make a good part.  CNC turning, on the other hand, streamlines the turning process using a computer numerical control or CNC system where the operators program the desired specifications into the machine’s computer which then translates the specifications into the appropriate turning operation.

It's a faster, more accurate, and repeatable process allowing manufacturers to run large quantities of parts more efficiently. Let’s quickly review the types of toolholders used on a lathe. The turning toolholder is a cutting tool in which the cutting edge consists of a separate piece of material that is either brazed, welded, or clamped onto a toolholder made of another material. The most common materials for the cutting edge are cermetic carbide. The more common, older by far, is the indexable holder. Indexable holders are typically constructed of a steel body that have precisely machined insert pockets and clamping systems allowing for the accurate, repeatable positioning of the indexable insert.

The indexable inserts are removable cutting tips, which means they are not brazed or welded to the tool body. They’re indexable meaning they can be removed and rotated to a new cutting edge without disturbing the overall accuracy of the tool.

We hope this edition of Seco Shop Talk covering the basics of turning gave you a bit of understanding of the turning process. Our goals for these videos are to keep it simple, short, and fun, along with helping you understand what’s going on inside the walls of the manufacturing world.

Please be sure to search for other editions of Seco Shop Talk online at secotools.com or you can find them on Seco’s YouTube page. I’m Gary Meyers and I hope to see you again on another edition of Seco Shop Talk.