What Is CNC Machining?
Computer Numerical Control
What Does CNC Stand For?
CNC stands for Computer Numerical Control. Computer Numerical Control (CNC) machining is a way of making things in which factory tools and machinery are moved by computer software that has already been programmed. This method can be used to control a wide range of complicated machines, including grinders, lathes, mills, and CNC routers. With CNC machining, cutting tasks in three dimensions can be done with just one set of instructions.
Manual control has its limits, which are overcome by the CNC process. With manual control, live operators are needed to move levers, push buttons, and turn wheels to tell machining tools what to do. From the outside, a CNC system might look like a normal set of computer parts, but the software and consoles used in CNC machining set it apart from all other types of computing.
Find out more about how CNC machining and CNC programming work if you want to use CNC manufacturing to make different things. You might also want to know what the most common types of CNC machines are and what they can do so you can see if they can meet your needs.
What is CNC Machining?
When a CNC system is turned on, the cuts that need to be made are programmed into the software and sent to the right tools and machines. These tools and machines then carry out dimensional tasks like a robot.
In CNC programming, the code generator in the numerical system often assumes that the mechanisms are perfect, even though errors are more likely when a CNC machine is told to cut in more than one direction at the same time. The part program is a set of instructions that tells a numerical control system where to put a tool.
Punch cards are used to put programs into a numerical control machine. On the other hand, small keyboards are used to give CNC machines their programs. The memory of a computer holds the CNC programming. Programmers write and make changes to the code. Because of this, CNC systems can do a lot more with their computers. Best of all, CNC systems are not static. Old programs can be updated with new prompts by changing the code.
What Is a CNC Machinist?
Machinists who work with computer numerically controlled (CNC) tools make and use tools that are controlled by both computers and machines to make other instruments and machines. They are in charge of the machines that make the speed and cuts needed to make a certain part. CNC machinists write programs that tell CNC machines how fast to make things and how many cuts to make.
CNC Machine Programming
In CNC manufacturing, machines are run by numerical control, in which an object is controlled by a software program. G-code is another name for the language used in CNC machining. It is written to control how a machine works, such as its speed, feed rate, and how it works with other machines.
Basically, CNC machining makes it possible to pre-program the speed and position of machine tool functions and run them through software in repetitive, predictable cycles, with little help from human operators. In CNC machining, a 2D or 3D CAD drawing is made and then turned into computer code that the CNC system can follow. After the program is typed in, the operator runs it as a test to make sure there are no mistakes in the code.
Because of these abilities, the process has been used in all parts of manufacturing, and CNC manufacturing is especially important in the metal and plastic industries. Find out more about the different types of machining systems and how CNC machine programming fully automates CNC manufacturing below.
Open/Closed-Loop Machining Systems
A closed-loop system or an open-loop system is used to control the position of a CNC machine during the making process. With the first one, signals only go from the CNC controller to the motor in one direction. In a closed-loop system, the controller can get feedback, which makes it possible for errors to be fixed. So, a closed-loop system can correct problems with speed and location.
Most CNC machining is done by moving along the X and Y axes. The tool is then moved and guided by stepper motors or servo motors, which move exactly like the G-code says they should. If the force and speed are low, open-loop control can be used to run the process. Closed-loop control is needed for everything else to ensure the speed, consistency, and accuracy needed for industrial applications like metalwork.
CNC Machining Is Fully Automated
With today's CNC protocols, most of the work of making parts is done automatically by the software that has already been programmed. With computer-aided design (CAD) software, the sizes of a part are set. With computer-aided manufacturing (CAM) software, the part is turned into a real finished product.
Different machine tools, like drills and cutters, may be needed for any given piece of work. So that they can meet these needs, many machines today combine more than one function into a single cell.
On the other hand, an installation could be made up of a number of machines and a set of robotic hands that move parts from one application to another but are all controlled by the same program. No matter how it's set up, the CNC process makes it possible to make parts consistently, which would be hard, if not impossible, to do by hand.
CNC Machine Types
Types of CNC Machine
The first numerical control machines were made in the 1940s. At that time, motors were used to control the movement of tools that already existed. As technology got better, analog computers and then digital computers were used to improve the mechanisms, which led to the rise of CNC machining.
The vast majority of CNC arsenals today are made up of only electronic parts. Ultrasonic welding, hole-punching, and laser cutting are all processes that are often done with a CNC. In CNC systems, the following are the machines that are used most often:
CNC mills can run on programs made up of numbers and letters that tell the machine how to move pieces across different distances. A mill machine's programming could be based on G-code or on a special language made by a manufacturing team. Mills have a basic system with three axes (X, Y, and Z), but most new mills can add three more axes.
On lathe machines, pieces are cut in a circle with tools that can be moved to different positions. With CNC technology, lathes can make cuts that are accurate and fast. CNC lathes are used to make complicated designs that couldn't be made on machines that are run by hand. Mills and lathes that are controlled by a computer have a lot of the same control functions. As with CNC mills, lathes can be controlled by either G-code or a code that is unique to the machine. Most CNC lathes, on the other hand, only have two axes: X and Z.
In a plasma cutter, the material is cut by a plasma torch. The process is foremost applied to metal materials but can also be employed on other surfaces. Plasma is made by combining compressed-air gas and electrical arcs. This gives plasma the speed and heat it needs to cut metal.
Electric Discharge Machines
Electric-discharge machining (EDM), also called die sinking and spark machining, is a process that uses electrical sparks to shape pieces of work into certain shapes. With EDM, a current flows between two electrodes, which cuts away parts of a workpiece.
When the space between the electrodes gets smaller, the electric field gets stronger than the dielectric because it is more intense. This lets an electric current flow between the two electrodes. Because of this, each electrode takes away parts of the workpiece. Some types of EDM are:
In a process called "flushing," a liquid dielectric carries away debris from each finished piece. The liquid dielectric appears when the current between the two electrodes stops and is meant to get rid of any more electric charges.
Water Jet Cutters
In CNC machining, water jets are tools that use high-pressure water to cut through hard materials like granite and metal. In some cases, sand or another strong abrasive substance is added to the water. During this process, factory machine parts are often shaped.
Water jets are used as a cooler alternative to other CNC machines that use a lot of heat to cut materials that can't handle it. Because water jets are cooler, they are used in industries like aerospace and mining, where they are used for carving and cutting, among other things. Companies also use water jet cutters when they need to make very precise cuts in materials. This is because the lack of heat prevents any change in the material's properties that could happen when metal cuts metal.