CNC gantry milling machine has two moving modes, respectively fixed column CNC gantry milling machine and moving column CNC gantry milling machine.

When fixed column CNC machine tools work, the processing workpiece as required is fixed on the worktable. The worktable is movable. The worktable drives the workpiece to move, so as to complete the processing task.

The advantage of the fixed column CNC gantry milling machine is reflected in the high precision of the machine tool. Because the beam and column of the CNC gantry milling machine are fixed, the machine tool has considerable stability, so the machining precision of the machine tool is very high. The disadvantage of fixed beam CNC gantry milling machine is that the machining limitations of the machine tool are high. The workpiece has to be smaller than the worktable.

On the contrary, the worktable of the moving column CNC gantry milling machine is fixed. The advantage of the moving column CNC gantry milling machine is reflected in the low price of the machine tool. The moving column CNC gantry milling machine works by moving the beam and column. The structure design of the machine tool is two guide rails, one beam and two columns move on the two guide rails, so the weight of the machine tool is relatively light, which reduces the cost of the machine tool.

Moreover, the worktable of the moving column CNC gantry milling machine is fixed on the ground, which has no limitation on the weight of the workpiece. The disadvantage of the moving column CNC gantry milling machine is that the accuracy of machining workpieces is not high. Because the column and beam of the moving column CNC gantry milling machine moves on the guide rails, the machining driving head has no certain stability, so the accuracy of machining workpieces will not reach high accuracy. This machine tool can only be applied to user groups with heavy and large workpieces and low machining accuracy.