Milling Machine Anatomy - Produced by Glacern Machine Tools - A Crash Course

A milling machine is a machine tool with a rotating cutter - typically used to shape, slot and drill solid metal workpieces. Most machines have 3 axis of movement - X, Y and Z.

On a manually operated conventional milling machine, the milling table can be moved side to side along the X-axis using one of two hand wheels. The table sits on a structure called the saddle which can be moved transversely along the Y-axis.

The spindle which holds and rotates the cutting tool is housed is housed in the milling head and can be moved vertically along the Z-access. Z-access movement can be accomplished by moving the entire head vertically along the column. Alternatively, the lever-operated quill can provide rapid vertical movement for operations such as drilling.

The Vertical Machining Center, or VMC, is a computer-controlled CNC milling machine. Movements are very similar to those of conventional milling machines - the table moving along the X-access, the Y-access - and the spindle head moving vertically along the Z-access.

Machine structures such as the table, saddle, and milling head, slide along a set of rails. Some machines use linear motion guides, which are low in friction through the use of circulating ball or roller bearings. Other machines use cast-iron 'box ways' which can be more rigid - at the expense of added friction.

Hand wheels are used to apply power for axis movement on manual machines. Highly accurate servo motors are used to apply power on automated CNC machines. Lead screws translate rotational movement into linear motion.

CNC machines use ballscrews and ballnuts. Ball bearings which circulate within the ball nuts reduce friction while increasing the accuracy.

Milling machines available for sale today: