Spindle
The rotating shaft that holds and drives the cutting tool. On a vertical
milling machine, the spindle axis is vertically oriented and can often be lowered like a drill
press.
Worktable
The flat surface where the workpiece is clamped. It features T-slots for
securing work and moves longitudinally (X-axis) and transversely (Y-axis) relative to the
spindle.
Knee
The massive casting that supports the saddle and worktable. It slides
vertically along the column to provide Z-axis (up and down) movement for adjusting the depth of
cut.
Column & Base
The main structural backbone of the machine. The heavy base provides
stability on the floor, while the rigid column houses the main drive motor and supports the knee
and head.
Quill
The sliding cylindrical mechanism inside the head that houses the
spindle. It allows the spindle to be extended downwards independently of the knee, useful for
drilling operations.
Overarm / Ram
The heavy casting on top of the column that supports the milling head.
It can slide back and forth, allowing the operator to increase or decrease the reach of the
spindle over the table.