Milling machines are normally used to machine cubic work pieces. However, manufacturers will use turning centers (shown in Figure 1) to shape the dimensions of cylindrical work pieces.
During turning operations, the work piece is held and rotated in a spindle. A non-rotating cutting tool is moved against the rotating part to remove material. Because the Z-axis is always parallel to the spindle of the machine, it no longer describes up and down motion of the cutting tool. Instead, the Z-axis now describes the back and forth motion of the tool along the length of the work piece, parallel to the spindle. The X-axis specifies the distance of the cutting tool from the center of the work piece. Figure 2 shows both the X- and Z-axes.
The X-axis position of the cutting tool determines the diameter of the cylindrical work piece. On the typical turning center, the Y-axis is not programmable. In theory, the Y-axis defines the tool height. However, because the tip of the tool must cut on the centerline of the part, the tool is almost always fixed at the same Y-axis location.
During turning operations, the work piece is held and rotated in a spindle. A non-rotating cutting tool is moved against the rotating part to remove material. Because the Z-axis is always parallel to the spindle of the machine, it no longer describes up and down motion of the cutting tool. Instead, the Z-axis now describes the back and forth motion of the tool along the length of the work piece, parallel to the spindle. The X-axis specifies the distance of the cutting tool from the center of the work piece. Figure 2 shows both the X- and Z-axes.
The X-axis position of the cutting tool determines the diameter of the cylindrical work piece. On the typical turning center, the Y-axis is not programmable. In theory, the Y-axis defines the tool height. However, because the tip of the tool must cut on the centerline of the part, the tool is almost always fixed at the same Y-axis location.
