Machining is a well-known technique of shaping material and thanks to its efficiency and precision potential become a standard in many production-focused industries. From automotive and airplane parts to small elements for home decor – that manufacturing process is a perfect technology to produce high quantities of repetitive elements while maintaining tight tolerances.
Although the machining itself is most commonly connected to metal parts manufacturing, said technology can shape almost any type of material – eg. many types of alloys, shapes composed in resins, and even plastics (like POM) or wood (also – plywood).
Machining became even more important since the introduction of computer numerical control in the 1950s. Since then devices like lathes, milling machines, and sanders could be controlled by computer and executed – repetitively and precisely, with high speed and pristine surface finish – given sequence of moves and cuts to produce high quantities of practically identical parts. The tight tolerances and high efficiency of that process made CNC machining services an industry standard.
What is the machining and how can we categorize that?
Machining – sometimes called "the removal treatment” – is a process focused on removing excess material from the block to achieve the desired shape of the part. Redundant material is usually cut out in the form of shavings by specialized cutting tools (blades, bits, or cutters) and the process itself is performed on a block of the raw material.
- milling - removing material with the cutter mounted to the rotating mill spindle; that process allows to achieve almost every type of shape – 2D and 3D,
- turning - that process focuses on removing excess material from the block mounted to the lathe spindle with specialized bits; said technology is focused on manufacturing rounded parts and elements,
- planning - removing material with a planner (handheld or mounted),
- drilling - making holes with chosen drill bit; it is worth mentioning, the drill bits differ from milling cutters (although – share some resemblance),
- grinding - removing small parts of the material with abrasive surfaces; usually, that type of processing is used in the final stage of the process to better surface of parts,
- CNC machining - it can be any of the processes mentioned above but controlled by a computer that executes commands translated to a G-code from the CAD file.
The machining itself can divide into two main groups:
- chips processing, executed by devices with regular geometry and number of blades and the excess material is removed in form of chips/shavings,
- abrasive treatment, executed by a vast variety of sanding tools, and the excess material is removed in the form of very fine shavings and dust.
What does the machining process look like?
The best description of the machining is showcasing the steps of that process. Each one focuses on different types of material removal and differs due to precision, quality of surface, and the amount/form of shavings (chips) removed from the block of material.
These stages are:
- initial machining, also called roughing – focuses on removing the vast majority of excess material; the quality of the surface is poor, but that stage provides the most efficient material removal,
- medium precision machining, that focuses on giving processed object raw shape, close to the final one,
- precision machining, that focussed on the final shaping of manufactured parts,
- final machining, usually focused on bettering the surface by sanding and polishing.
Each of these steps can describe machining processes like milling, turning, or sanding. On the other hand the type of process – in other words: what type of machine should be used to achieve desired effects – depends on:
- type of machining material (metal alloys, wood, plastics, etc.),
- overall size of processed material and final form of part,
- type of desired part – lathes and turning is the best to produce cylindrical parts (although similar effects can be achieved on mills, yet not as efficiently). Milling machines are perfect for the production of complex parts, especially CNC mills, that allow high precision and repetitiveness of manufactured elements
The final product of the said process is a part with desired shape and properties, ready for other actions, eg. anodizing (for aluminum).
Utilization of machining
The machining of materials such as alloys, wood, glass, stone, plastics (and more) allows the production of a high variety of elements and parts of almost all shapes and sizes. High precision provided by CNC machining gives almost unlimited possibilities for repetitive/mass production of elements, even very complex ones.
Currently, machining (especially: CNC) is utilized in production for industries such as:
- automotive (a vast variety of car parts, from small details and bushings to whole engine blocks, etc.),
- airplane (rotors, engine parts, etc.),
- energy industry (parts for transformers, etc.),
- overall home decor industry (home appliances, small aesthetic details, etc.).
That list is only the tip of the iceberg of all contemporary applications for machining. In other words: almost every industry (if not: every) utilizes some kind of milling due to the requirement of high-quality parts, produced with minimal tolerances in mind. And that leads to the common use of many types of CNC machining.
CNC machining and traditional forms of manufacturing
Processes like milling or turning have been known almost since the dawn of the industrial age. Precision and efficiency made that technology popular and widely available. Before the CNC took that area of manufacturing by storm, to produce high quantities of parts and elements, operators used a vast variety of templates to achieve repetitive effects of work: milling or turning. Said tools were available since the popularization of automated mills and lathes, powered by some form of the engine (usually electric).
The development of CNC technology made fast and precise production of high quantities of parts and elements easier. Older forms of said processing (that utilized automatic mills or lathes) allowed the production of even the most complex shapes but required much more strict quality control and the tolerances between produced elements were big, sometimes beyond given specification.
On the other hand: said production is required from the operator's manual control over the spindle or tool bit during machining. Thus – mass production of parts was limited by the time of people who were machining elements.
Although the utilization of additional tools to speed up work (eg. templates), hand-lead mills or turning machines will not allow the production of the same quantities of parts as CNC with similar precision.
CNC machining devices allowed to speed up the whole production and decrease the cost of production. Thanks to that, machining pricing became more attractive to clients, especially in the production of high quantities of CNC-manufactured parts.
Still: traditional machining of metals and plastics is still important and has its place. Production of single elements (eg. turning of one unavailable part) is still more economically efficient. On the other hand – in mass production, the CNC machining process is an industry-standard.
40 years of CNC machining in RADMOT
At RADMOT, we can offer CNC milling services, CNC turning services as well as many additional services, including washing, aluminum anodizing, laser marking and assembly.
Contact us and tell us what you need. We have been providing CNC services for almost 40 years. Our quote is completely free. And if you are in doubt about which technology will work best for you, we are able to advise customers from many industries on machining and quickly determine the price of machining the parts you order - our expertise is at your disposal.