Working with CNC equipment: Inspection Efficiency

Anybody with half a brain can immediately see the usefulness of computer-controlled equipment. The ability of a machine to telescope the work processes so they run in parallel instead of series can turn a single machinist into a one-person army. Think of it this way: A manual machinist does 1 man-day’s worth of work in 1 day, right? What if he could do 4 or 6 man-days of work in that same day?

CNC machines should be considered new and faster manufacturing tools, allowing a company to be more competitive or to increase its profit. They should not be thought of as machines that displace or make manual machine operators obsolete. It’s just technology!

I tell people I don’t really want to be on the cutting edge of technology, but I sure want to be riding on the blade. I was fascinated by CNC machines and their ability to do the tasks they do with such simple-looking instructions. At the time, it was all secret code I didn’t understand. For many machinists, the learning curve is steep, especially adding the complexity of using desktop computers, which perform a large part of the programming duties.

A few words of advice: Don’t go the way of the Wisconsin ice cutters. Most experienced manual machinists already know all the hard stuff, such as determining speeds and feeds and how to hold workpieces. Although most computer jockeys can figure out the controls on a modern CNC machine pretty quickly, it takes them 10 years to figure out how to hold tools and workpieces and then which tool performs what task. So hang in there, taking small, steady steps. By all means, take advantage of these machines.

One challenge I found difficult when learning to run CNC equipment was there was absolutely no sense of feel. Manual machinists develop an accurate sense of feel for something, such as how hard they can push a tool and how deep a cut they can take with a particular setup. This sense of feel has no place with automatic equipment. I had to learn the actual “numbers” for speeds and feeds when programming CNC machines.

The current crop of CNC machinery is so blindingly fast, it’s frightening. For most jobs, you cannot even approach the maximum available feed rates for the equipment. The machining world is waiting for the cutting tool industry to catch up with the machine tool builders because the cutting tools are the gating factors for achieving the highest metal- removal rate.

My experience with CNC machines is in the job shop environment, where the tips and tricks I developed are related to highly varied work and many different workpiece materials.

• Try to reduce cycle times for multiple or long-run parts, but never at the expense of consistency or predictability. A machinist can do much more productive and profitable work than babysit a temperamental process.