When I first started machining, CNC machines were just coming into mainstream use. The first few shops I worked in had only conventional machines. It wasn't until the mid 1980's I started to notice the incredible versatility of CNC machines. The contouring and shapes the machines could generate made many jobs much easier. The use of templates to file and sweep in surfaces was rapidly becoming a thing of the past.

Initially, I was intimidated by the technology and couldn't imagine how a person could machine parts simply by pushing buttons on a control panel. The mysterious code that ran the machines seemed to be the domain of computer people and was seemingly beyond my comprehension. It wasn't until later when I took a class in programming that the mysteries started quickly dissolving. Taking a class in programming is a great way to get started in CNC machining.

As versatile as CNC machines are, they are only as good as the people programming and operating them. The clich "garbage in garbage out" is well suited to CNC programming and machining. There is simply no substitute for proper planning and machining know-how. A programmer without much machining experience would likely struggle to produce good parts consistently.

One of the great virtues of CNC machines is that while they are running, the machinist or operator can be doing other things. In essence, they take the labor out of machining.

Another virtue of CNC machines is that the cutting and measuring process so...