Machine Tool Technology Basics

CNC Machining Centers

Machining centers evolved from the need to be able to perform a variety of operations and machining sequences on a workpiece on a single machine in one setup. Many parts require machining on several machines and may spend weeks on the shop floor waiting and moving from machine to machine. Operations such as milling, contouring, drilling, counterboring, boring, spotfacing, and tapping can now be performed on machining centers in any sequence and require only one setup. Machining centers equipped with automatic tool changers, rotary tables, and rotary work heads make this a very versatile machine while reducing the operator intervention during the cutting cycle.

CNC bench-top machines are widely used in high schools, community colleges, and industrial training programs to teach the basic fundamentals of CNC programming. The bench-top machines are usually equipped with Fanuc compatible control units, Fig 36-1. Instructors and students have found these machines ideal for teaching and learning purposes because of their smaller size and simplicity of operation. They are relatively inexpensive and programmed using the same G and M codes as industrial-size machines, but use smaller workpieces and take lighter cuts.

Types of Machining Centers

Machining centers can be classified into two main types: the vertical spindle and the horizontal spindle machine. The main difference between the two is the type of work that can be done on them efficiently.