CNC machines have been found suitable for the following:
1) Parts having complex contours, that cannot be made by conventional machine tools.
2) Small lot production, often for even single(one off) job production, such as for prototyping, tool manufacturing, etc.
3) Jobs requiring very high accuracy and repeatability.
4) Jobs requiring many set-ups and/or when the set-ups are expensive.
5) Parts that are subjected to frequent design changes and consequently require more expensive manufacturing methods.
6) The insepction cost, which is a significant portion of the total manufacturing cost.
The selection of type and size of machining centers depends on several factors, especially:
1) Type of products, their size, and their shape complexity.
2) Type of machining operations to be performed, and the type & number of cutting tools required.
3) Dimensional accuracy required.
4) production rate required.