CNC machines can easily make complex contour cuts and three-dimensional shapes such as turbine blades, unlike manual machines which are limited by the need for an operator's direct control and cannot perform such complex tasks.
CNC machines excel at creating complex geometries and precise, repeatable parts, which are tasks that are challenging for manual machines. Two part features that CNC machines can easily manufacture but manual machines cannot include intricate contour cuts and complex three-dimensional shapes. An example of an intricate contour cut would be a complex, multidimensional profile in a metal part, which requires advanced control over tool movement that CNC machines provide through programmed instructions.
Similarly, producing complex three-dimensional shapes like a turbine blade is achievable with the precise, multi-axis movements of a CNC machine, whereas it would be exceedingly difficult and less accurate if attempted with a manual machine.
In comparison, manual machining requires direct control by an operator and is limited to simpler tasks that don't involve complex movements or require high levels of precision and repeatability. The capacity of CNC machines to handle intricate programming allows for these sophisticated features to be created quickly and consistently, which is not feasible with manual machining processes.