Machining is a family of chip making techniques. The principle of machining is to remove material so as to give the blank the desired shape and size, using a machine tool. By this technique, we obtain pieces of great precision.
When machining a part, material removal is achieved by the conjunction of two relative movements between the part and the tool: the cutting motion ( cutting speed) and advance movement (feedrate).
There are two ways to generate the desired surface: by shape work or by envelope work. In the case of form work it is the shape of the cutting edge of the tool that conditions the surface obtained. In the case of envelope work, it is the conjunction of cutting and advance movements that defines the final surface.