1.Dimensions should conform to the characteristics of CNC machining
In CNC programming, the size and position of all points, lines, and areas are based on the programming origin. Therefore, it is best to directly give the coordinate size on the part drawing, or try to quote the size with the same reference.
2.The conditions of geometric elements should be complete and accurate
In programming, the programmer must fully grasp the geometric element parameters that constitute the contour of the part and the relationship between the geometric elements. Because all geometric elements of the part outline are defined during automatic programming, the coordinates of each node must be calculated during manual programming. No matter what is ambiguous or uncertain, programming cannot be performed. However, due to inadequate consideration or neglect during the design process, part designers often have incomplete or unclear parameters, such as whether arcs and lines, arcs and arcs are tangent or intersected or separated. Therefore, when reviewing and analyzing the drawings, you must be careful and contact the designer in time when problems are found.
3.Reliable positioning reference
In NC machining, the machining steps are often concentrated, and it is important to position with the same reference. Therefore, it is often necessary to set some auxiliary benchmarks or add some process bosses to the blank.
4.Uniform geometry type or size
It is best to use a uniform geometry type or size for the shape and inner cavity of the part. This can reduce the number of tool changes. It is also possible to use a control program or a special program to shorten the program length. The shape of the part is as symmetrical as possible, which is convenient for programming with the mirror machining function of the CNC machine tool to save programming time.