CNC mills are often classified by the number of axes on which they can operate or spindle directions.
1. Vertical Mill
A vertical mill or milling machine’s spindle axis is vertically oriented, which means the cutting tools on the spindle will shape the materials vertically, and the cutters move while the workpiece remains stationary, the machines can cut into the part easily. There are two basic types of vertical mills
– Turret mill: the spindle is stationary, the worktable that holds the material moves horizontally or vertically to complete the cutting
– Bed mill: the spindle is positioned on the vertical axis, allows for up and down moving, which combines with the horizontal movement of the worktable to performs the milling process.
2. Horizontal Mill
A horizontal mill works almost the same as vertical mills, as the name implies, the cutters on horizontal mills are mounted on a horizontal spindle. The cutting tools of horizontal machines have good support from the arbor and get a larger cross-sectional area than the vertical mill, which allows fast material removal speed, especially from grooves and slots.
3. 3-axis mill
On the 3-axis milling machines, the workpieces remain stationary while the cutting tools move along 3 axes to execute the operations for CNC milling parts with a variety of shapes, sizes and specifications.
4. 4-axis mill
On the 4-axis milling machine, the structure is generally the same as the 3-axis milling machine, except it’s equipped with a turntable, which can realize more operations.
5. 5-axis mill
5-axis means there are 5 directions in which the milling cutters can move. On the 5-axis milling centers, the cutting tools move along the X, Y and Z linear axes as well as rotates on the A and B axes to be close to the workpiece.