SST Shop Talk
Practical Applications of CNC
Computer Numerical Control or more commonly called as CNC’s are the new trend in machine shop manufacturing and practice. Any manufacturing environment owns one or is basically acquainted to this kind of device because of its capability to increase productivity as well as consistency on the products being produced.
Benchmarked from Numerical Control (NC) during the late 50’s, Computer Numerical Control incorporate the functionality of a Programmable Logic Controller (PLC), meaning you could program it to execute different functions depending on the type of manufacturing that the industry needs.
Given this kind of quality what does the Computer Numerical Control do in the practical application concept? CNC can do a variety of things depending on how the machine operator would program the system. The more acquainted the machine operator is to the CNC machine the more complex applications as well as programming can be made. Practical applications of CNC range from drilling, lathes, multi-axis spindles, milling machines, laser cutting machines, and wire electrical discharge machines.
Let’s discuss some of these common applications further. In Metal fabrication, Computer Numerical controlled Lathe’s are used to fabricate metal sheet by shearing, flame or plasma cutting, punching, laser cutting, forming and welding. Most CNC Lathe’s are used for designing modern carbide tooling. The design could be created with the Computer Aided Manufacturing (CAM) process, and when done, the CNC could start creating the product automatically with little supervision from the machine operator.
Electrical discharge machining (EDM) is the process of removing metal with the use of electrical sparks to take away the metal. These Electrical Discharge Machine has two types, the vertical EDM and wire EDM. Vertical EDM uses an electrode that is the shape of the cavity to be machined into a work piece. Wire EDM is used to create punch and die combinations in the fabrication industry. Computer Numerical Control EDM’s are not usually known because it is mostly incorporated to other CNC process.
Drilling is the most common machine process. Computer Numerical Controlled Drilling is used to create precise right circular cylinders over a certain material, the CNC could be programmed to create holes on different standards, most of the time this is the gaps between these holes. Drilling is commonly used in wood working manufacturing process in which other process is also involved such as milling, turning and grinding.
Several tools for creating holes with CNC’s involve varied hole sizes as well as drill press for creating different depths on its holes. CNC drills are equipped depending on the type of hole that the machine operator is drilling.
Applications stated above are just a few examples on what the Computer Numerical Control could execute. Depending on how you want it to perform, more complex designs can be made and a lot of things can be made in a shorter period of time, therefore the key concept for the proper use of CNC’s is that the machine operator must know what he or she wants to do.
This makes the CNC an indispensable tool for the Manufacturing Industry nowadays.
The Programmer
The first person is the CNC programmer. He is like the "playmaker". He will create the programs that the CNC machines are intended to execute. Since the programs are in the form of CNC codes fabricated like sentences, he should have mastered these codes because they work like a different language. The regular CNC machine can use up to 50 codes, so that's like learning 50 new words for the newbie.
Also, the programmer should have at least and engineering or machining degree. Remember that the CNC machine will only execute WHAT IT IS PROGRAMMED TO DO. If the program is wrong, the whole operation goes down the drain with it. Moreover he should also be flexible and have a fast turn-around because a CNC machine is often used to machine a huge selection of different work-pieces.
The Technician
The third person that will need is the CNC technician. Although this may still be the programmer, it is more convenient to always have a technical expert on-call because in the long run, you may have more than one CNC machine and you may need to prioritize over the other in case both gets crippled at the same time. Just like the programmer, the technician should also be flexible and articulate. CNC offers a lot of complexity when it is running right, how much more if it is behaving badly?
So, if you are having job openings for positions that need to be handling a CNC machine, ask the applicants first to do a demo for you and make sure that during the demo, they know what they're doing. An exam may also do wonders too. If they have no experience with any kind of CNC machine, it is advisable that you encourage them to take short courses on CNC.
Eighty-hour courses are available online and hey, it is better than nothing. Experts even encourage employers to hire CNC machinists who have finished AND PASSED the National Occupational Competency Testing Institute (NOCTI) assessment just so they could be sure that their CNC machines will go to good hands. After all, a CNC machine is still an asset.
The Operator
The second person that you need is the CNC operator. He will simply recheck the programs loaded to the machine and push the right buttons to get the work done. However, thinking that a CNC operator can have little or NO SKILL AT ALL is wrong. A CNC machine operator must have at least basic machining skills and he should have undergone some form of training to run a CNC machine.
These machines can produce very intricate motions, making it possible to make shapes that cannot be created on conventional machine tools. So, the operator should foresee this complexity and know how to cruise with it. The skills that an operator must have though, are lesser compared to the operators of conventional machine tools.
