The ‘CNC’ stands for Computer Numerical Control and the term CNC machining is a subtractive manufacturing process that employs computerized control and machine tools to perform certain tasks on the workpiece such as milling, drilling, turning, routing, grinding, etc. Unlike additive/formative manufacturing processes, subtractive processes involve the part of removing the unwanted material from the workpiece to create a custom design and shape. CNC machining can be used for a wide range of materials including wood, plastic, metal, glass, composites, and many hard materials to perform various applications. The CNC machine is an electro-mechanical device that uses computer programming inputs to manipulate the machinery tools and autonomously perform the operation of CNC machining. The machine has three primary components which are the Command function, Drive/Motion System, and the Feedback system. In today, many industries and factories have replaced manually operated machines with CNC machines in their manufacturing process due to its automated nature that provides faster speed, high precision, high accuracy works, and increase overall production.
How Does A CNC Machine Work?
The CNC machine is fully automated and works according to the digital instructions made on the Computer Aided Manufacturing (CAM) or Computer Aided Design (CAD) software. CAD software is the basic point for CNC projects as it uses to create the design. Some of the popular CAD software include AutoCAD, Rhino3D, and SolidWorks. The 3D model created in the software determines the dimensions and properties of the final product. CAM software helps to organize workflow, run cutting simulations and create tool paths before starting the cutting. It works with CAD software to generate the code that determines the movement of CNC tools and workpieces. Popular CAM software are Edgecam, Mastercam, OneCNC, etc.
The program is a group of coordinates that guides the operation of the process, it chooses the right parameters such as cutting tool, cutting speed, voltage, etc. All the information will be translated into the code (M-code and G-code) that the machine can understand. G-code is the geometric code that tells the machine how to move and determine the speed of the cutting heads. On the other hand, M-code is a machine code that provides all the information that is overlooked by G-code, including information about the change of tool, the use of coolant, program stop, etc. Both codes are very important to the machining process. The controller on the CNC machine will then read the programming code to interpret the design and move the cutting tools and workpiece on multiple axes to create the desired shape on the workpiece.
Basically, the CNC machining use software to pre-program the movement, speed of the machine tool and run them in a repetitive and predictable cycle, with litter involvement of the human operator. The machinists or operators must gain knowledge on both metalworking and programming under proper CNC machining training. The skilled machinists oversee each phase of the process from the creation of concept, design, coding, to the finished product. It is a crucial role that involves creativity, innovation, and manufacturing during the life cycle of the product.
The advanced model of the CNC machine may hold multiple tools to perform various cutting tasks. It is also able to move the tools in at least two different directions which is called Axes. The more axes it has, the more complicated it is. These movements can be either linear or rotary which allows them to operate in a full 180º hemisphere or even more. For instance, a five-axis milling machine has three linear axes (X, Y, Z) and two rotary axes. It may also have more rotary axes in the CNC machine.
Types of CNC Machining Operations
There are different types of CNC machines available today for performing various automated processes in a wide variety of industries such as construction, automotive, aerospace. Here we will introduce a few common CNC machining and tools that are widely used in current industries.
Drilling
The drilling process uses multi-point drill bits to create holes in the workpiece. The CNC machine rotates the drill bit perpendicularly on the workpiece surface and produces the vertically aligned holes in a diameter same as the diameter of the drill bit that is used in the drilling operation. CNC Drills are able to make holes with high precision and accuracy. With the use of specialized machine configuration and devices, it can also perform angular drilling operations.
Milling
Milling is the most common CNC machine use today. It is a machining process that rotates the cutting tools to remove unwanted material from the workpiece. It can perform several operations such as end milling, face milling, chamfer milling, drilling, tapping, boring, etc. The ability to produce a wide range of complex parts is its greatest advantage.
Turning
The CNC turning is typically known as a CNC lathe machine. It employs single-point cutting tools and feeds the cutting tool in a linear motion along the material surface to remove material from a rotating workpiece. It produces round or cylindrical parts with external and internal features.
Grinding
CNC Grinding machine employs a rotating grinding wheel to remove material from the workpiece. It is mostly used for finishing operations as it can provide a high precision and quality finishing to the metal surface.
Plasma Cutting
The CNC plasma cutter uses a plasma torch to cut the programmed shapes out of the base material. It is primarily applied on metal sheets, but it can also be used on other materials. In order to generate a lot of heat and speed needed for performing the cutting, compressed air/gas is combined with electrical arches to produce the plasma.
Others
The invention of new tools and methods of performing the task has created many new CNC machines such as 3D printers and others. Custom CNC units and systems are created to fulfill special industrial requirements with the aim to transform nearly every step of the fabrication into automation. Some other types are polishing, picking, loading, sewing, embroidering CNC machines, and more.
In conclusion, CNC machines are used in a variety of applications and industries due to their versatility. It helps to expand the capability of the manufacturing process, improve the speed, and quality of the product. MecHero Malaysia offers different types of CNC operations for meeting your project requirements. You can always contact us at +6011-7000 7687 or email us at my.mechero@gmail.com for an inquiry about the service of CNC machining or the supply of CNC machines in Malaysia for industrial usage. As a steel and online hardware store Malaysia, we also supply a wide range of steel materials, general hardware, or mechanical components. Tell us your requirements now and we can advise you accordingly.
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