Machining is a general word for the processing of material by machines or by hand which removes chips from the base product. Machining makes the product smaller and thus permanently changes its shape. It also reduces the mass and weight of the base product. Various examples of machining are described below, together with an explanation of their use.
Example of machining
An example is a carpenter who uses a plane to remove chips from a door to make it fit into a frame. As chips are shaved off the door, the door becomes smaller and in fact lighter, although the weight of a few chips will not have a big effect on the total weight of a door. The shape of the door also changes as it becomes slightly smaller to fit into the intended frame. The door has definitely changed shape due to planing. A carpenter, when planing, must be very careful not to scrape too much off the door because, as a rule, a trowel can no longer be glued to it. The curls created during planing are called chips. The shavings form waste that is removed after machining.
There are several machining operations present within the technique. The machining technique that is chosen depends on the goal to be achieved. When holes need to be drilled, one can start drilling with a column drill, for example. This is a machining technique. When something has to be made to measure, one can use saws but also planes and files. Grinding, for example, is also possible. In addition, turning, milling, boring, honing, tapping and gouging (of wood) belong to machining operations.
Turning and milling
Turning and milling are special machining operations. Turning is done on a lathe and milling on a milling machine. With these machining operations, the shape of basic material can be changed to a great extent. These forms of machining are used both within mechanical engineering and within the woodworking industry. Turning and milling can be done both conventionally and computer-controlled on a CNC turning or milling machine. CNC stands for Computer Numerical Control. This means that these machines are computer controlled.
Application of machining in technology
Machining is used quite widely in engineering. Wood, metals and plastics can generally be machined well. Within the woodworking industry, chipping is used for the furniture industry, for stairs, and for carvings that are applied for decoration, among other things. In addition, within the wood industry, many holes are drilled and boards are cut to size.
In mechanical engineering, machining is used in machine factories for turning shafts or making machine parts by means of milling. Parts are also machined for the oil and petrochemical industries. A number of parts from which a lathe or milling machine is assembled are themselves manufactured by lathes or milling machines.
Safety in machining
Safety is an important aspect in machining. Among the tools used are saws, drills and chisels. These tools are sharp and must be handled properly to prevent damage or injury. Rotating tools such as drills and chisels can also grab onto items of clothing and clamp or even break them at a very high rate. This can cause serious accidents. Chips must also be disposed of properly. Metal chips and wood chips can be sharp. Therefore, care must be taken to ensure that the chips cannot come close to the eyes of the machinist or other personnel. Wearing safety glasses is therefore mandatory in many cases. Many turning and milling machines have a special safety cover with which the machine can be closed. The machinist stands safely behind a transparent screen so that he or she can still see the process.
Work in machining
There is a high demand for experienced turners and millers within mechanical engineering. This is because there are few professionals in this field available on the labor market. A good turner or milling machine can quickly find work at a machine factory. Therefore it is important that his or her knowledge is up to date. Nowadays, more and more machining is done with CNC machines. It is important that a machinist is not only able to provide these machines with new materials that need to be machined. A good machinist can independently program a CNC machine so that the machine performs the correct operation on the product. Before a machinist becomes an independent CNC programmer, however, he or she will need to have built up the necessary experience and also have a great deal of knowledge of materials.