David Thacker
The earliest CNC machines were created in the 1940s and 1950s. The technology they relied on back then were called punched or perforated paper tape. This technology is obsolete today as data medium moved to analog then quickly to data processing from the 150s onwards to the 1960s.
What is CNC Machining?
CNC machining is short for Computer Numerical Control. It is a term used to describe a manufacturing process where pre-programmed computer software drives the movement of factory tools and other machinery.
CNC machining process can control a host of sophisticated machinery such as lathes, grinders, mills, and routers. With CNC, a single set of prompts can accomplish three-dimensional cutting tasks.
How it Works
Machining is a way of transforming a piece of material such as a plastic block and derives a finished product, mostly a prototype, using a controlled process. The CNC machine gets digital instructions from a Computer-Aided Design (CAD) or Computer-Aided Manufacturing (CAM) file and interprets the design as an instruction to cut prototype parts.
This ability to manipulate computer devices to control tools increases productivity by automating labor-intensive and highly technical processes. Automation improves the accuracy and speed with which prototype parts are manufactured.
Types of CNC Machines
CNC machines fall into two categories:
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Conventional machining Technologies
- Drills which operate by spinning a drill bit, shifting the bit around to get into contact with a material block
- Lathes are the opposite of drills. They instead turn the material block against the drill bit, instead of the bit turning into the material. Lathes make contact by moving a cutting tool laterally until it touches the material.
- Milling Machines are widespread today, and they use large part machining to out material from the stock.
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Novel Technologies
- Electrical and Chemical Machining: Various technologies make use of specialized methods to cut into the material. This includes Electrochemical, Electron Beam, Photochemical machining, etc. These methods are incredibly dedicated and only used in exceptional cases for carrying out mass production using a unique material
- Other Cutting Mediums: Various novel technologies make use of a variety of material cutting mediums. These include oxyfuel, plasma cutting, and laser cutting.
Things to learn about CNC Machining
- When you activate a CNC system, you program the desired cuts into the software and instruct to the corresponding machinery and tools, which perform the dimensional tasks you specify, just as a robot would.
- The code generator in the numerical system in CNC programming often assumes the mechanisms are perfect, whether or not there is a possibility of mistakes. The possibility of errors becomes higher when the CNC machine gets direction to cut in different directions at a go. Tool placement in a CNC system is shown by several inputs, which are called the part program.
- With a numerical control machine, punch cards are used to input programs, while with a CNC; the computer’s memory retains the program, with the machines fed to the computers via small keyboards. Programmers write and edit the code, and the CNC systems have a larger computation capacity. Newer prompts can be added to pre-existing programs by revising code.
Crash prevention On CNC Machines
Detecting a crash and stopping it is possible by installing encoder-disk position sensors. To determine whether the CNC machine is moving as it should, and to stall undetected cutting, torque sensors can be used. In industrial CNC machines, closed-loop controls are used, where the monitor knows the axis position. When appropriately controlled, the crash potential significantly lowers, but the onus still falls on the programmers to input codes correctly for safety.
Conclusion
CNC machines have been around for decades. They have come a long way from using perforated tape and now use sophisticated code to run. The more conventional types of CNC machines include lathes and milling machines. The more novel types are more specialized such as electrochemical and Electron Beam.
