A machinist is defined as someone who operates a machine tool. Pretty simple, right? But just as in the medical profession, where there's a doctor for pretty much every part of your body, so too do machinists specialize in various aspects of their trade. These include tool and die machinists, moldmakers, and of course CNC machinists. As a rule, the type of machine tool you stand in front of each day has long been the defining factor for what you call yourself:
- Turning guys and gals set up and operate lathes, while those who stand in front of milling machines all day are, appropriately enough, called milling people. The key difference between the two is simple: On a lathe, the workpiece rotates while the tools remain stationary. On a mill, it's just the opposite.
- If you operate a cylindrical or centerless grinder, your job title might be simply "grinder" (as in, "Hi, I'm Gary the grinder"). And if you're one of those who argue that abrasive processes such as this are technically not "machining," please remember: Grinding wheels produce chips, albeit very small ones. So there.
- The same can be said for electrical discharge machining, or EDM, because the copper or graphite electrodes used in this process blast away tiny particles of metal, a phenomenon known as erosion. No one calls EDM operators "EDMers," though, just EDM operators. Check on Craigslist and you'll see.
The newest machine tools (and the people who run them) don't fit inside neat little boxes. Multitasking and mill-turn centers perform milling and turning operations in a single machine, as do Swiss-style lathes. Five-axis mills combine the best of both vertical and horizontal machining centers, and so-called hybrid machine tools do grinding, welding, hobbing (the process of making gears), and even laser cutting, all in the same machine.
