Finishing

Difference between rough cut and finish cut in machining

Machining or metal cutting is one of the secondary manufacturing processes by which excess material is gradually removed from a preformed blank to obtain desired shape, size and finish. There exist larger number of processes to fulfil the basic requirement of machining. Such processes can be broadly classified as conventional machining processes (turning, threading, facing, drilling, boring, shaping, planing, milling, grooving, reaming, etc.), abrasive cutting processes (grinding, lapping, honing, polishing,

Surface profile of a highly finished surface

Primary aim of secondary manufacturing processes is to obtain products having better surface quality, high dimensional accuracy and close tolerance. Such processes include machining or metal cutting operations (like turning, milling, drilling, reaming, precision turning, grinding, lapping, honing, AJM, USM, EDM, LBM, IBM, etc.) and surface modification operations (like heat treatment, coloring, coating, etc.). Each of these processes has varying level of capabilities in terms of surface quality and precision.

Surface integrity (SI) data set by Field et al. (1972)

Functional performance of any solid surface relies on the physical conditions and chemical composition of the concerned surface and subsurface layers. Quality is defined as fit for intended purpose. Similarly, quality of a solid surface is one subjective matter and its assessment primarily depends on intended functionalities. Let us explain the same with examples. With respect to decorative artefact, appearance of the surface has importance rather than presence of micro-cracks

Conventional machining - rake angle and clearance angle

Conventional machining or metal cutting operation is performed to gradually remove excess layer of material from the workpiece to impart intended shape, dimension and finish. Material removal is realized with the help of a small device called cutter or cutting tool. During machining, the cutter as well as the workpiece is rigidly mounted on the machine tool with the help of various arrangements. Relative velocity between cutter and workpiece is

Typical grinding process - a finishing operation

Machining or metal cutting is one of the manufacturing processes by which excess material is gradually removed from a pre-formed blank to provide desired shape, size and finish. It is one subtractive manufacturing process that is primarily used to improve dimensional accuracy and tolerance level. To efficiently and economically process various materials in several ways, there exist various machining processes, each having different capability in terms of material removal rate

Typical face milling process - a machining operation

Fabricating complicate shaped products with good surface finish by casting is not always feasible and economical. Various secondary operations can be performed on the casted products to finally produce the desired object. Such operations include joining (such as welding), material removal or machining, heat treatment or property alteration, coloring and coating, etc. Material removal processes basically removes material from workpiece surface to provide intended dimension and tolerance. A large number