Knee milling machines are fundamental to many engineering and fab shop floors. To appreciate their usefulness, first define them by their unique Z-axis architecture. Unlike a bed mill where the head travels over a fixed bed, a knee mill is a vertical mill where the workpiece table is attached to a large cast iron knee.
The knee moves up and down along a column, exposing the X-axis (left/right), Y-axis (forward/back) from the horizontal table on top of the knee, and the spindle with the cutting tool hanging down from above. The spindle is held in a quill that can move up and down independent of the knee mill’s Z-axis. The knee is the primary vertical adjustment, but the quill carries out the detailed vertical motion of the cutting tooling. This mechanical layout gives knee milling machines ...
