The reasonable choice of cutting parameters is the principle, rough machining, general to improve productivity, but also should consider the economic and the processing cost; semi finish machining and finish machining, should be on the premise of ensuring the processing quality, both the cutting efficiency, economy and the processing cost. Should be based on the specific numerical machineinstructions, cutting manual, combined with the experience and.

The cutting depth of T. In the machine tool, workpiece and cutting tool rigidity allow circumstances, t is equal to the machining allowance, which is an effective measure to improve productivity. In order to guarantee the machining precision and the surface roughness, the general should leave some margin for finishing. Precision machining allowance of CNC machine tools is slightly less than the general machine tools.

The cutting width of L. General L and tool diameter is proportional to D, and inversely proportional to the depth of cut. Economic type CNC machining, range of general L is: l= (0.6 ~ 0.9) d.

The cutting speed of V. V is a measure to improve to improve productivity, but the relationship between V and the tool life is close. With the increase of V, the tool endurance decreased rapidly,so the choice of V mainly depends on the tool durability. In addition, the cutting speed and machining of materials have great relations, such as alloy steel for end milling 30crni2mova, V can use 8m/min or so; and with the same end milling of aluminum alloy, V optional 200m/min above.

The spindle speed of n (r/min). The spindle speed is generally based on the cutting speed is V to the selected. The formula for calculating the:

In the formula, D is the tool or workpiece diameter (mm).

The control panel of CNC machine tools on the general with the spindle speed trim (magnification)switch can be integer multiples of the spindle speed adjustment in machining process.