Machine shops use a variety of tools to cut, drill, or shape metals, plastics, and ceramics. For some, a plasma cutter may be less familiar than lathes and other computer-controlled CNC machine tools. There are small CNC plasma cutters suitable for hobbyists and small jobs. Still, many manufacturing and industrial clients need a commercial machine shop like Hamilton Machine to handle their metal CNC machine jobs. These powerful gas-plasma devices offer several benefits by the nature of their design and computer controls. It is important to note that this article is about table-sized tools, not handheld plasma cutters.
What Is a CNC Plasma Cutter?
These machine tools use a gas forced through a nozzle and hit with an electrical arc, separating atoms into plasma. This plasma jet easily cuts into conductive metals. Plasma cutting uses different types of gases depending on the needs of a particular job. Nitrogen, methane, oxygen, compressed air, and a mix of argon and hydrogen are just a few of the gases used.
Manually operated tools handle a variety of cutting, milling, and shaping operations. All those manual machines can be useful and effective, but they have a couple of important disadvantages relative to computer-controlled tools – speed and precision. A computer-guided plasma torch will always be faster and more precise than even the best human welder. The accuracy and speed of computer-controlled tools benefit both the tool owners and CNC machine shop customers.
Benefits for Customers
Plasma cutting offers several potential benefits relative to mechanical cutting or milling, though the size and nature of the benefits will depend on the job. If you buy your own metal CNC machine tools or outsource to a place like Hamilton Machine, here are some advantages to keep in mind:
- Versatility – Plasma cutting tools can make simple or complex cuts in brass, copper, steel, or stainless steel. Other cutting and milling tools may be less flexible or much more expensive.
- Productivity – The power of a CNC plasma cutter allows for cutting at up to 500 inches per hour without pre-heating or cooling to prepare the workpiece. Of course, the operating speed will depend somewhat on the device and the metal it cuts.
- Better milling performance – A plasma torch cuts with more precision and has an insignificant risk of unwanted chips or other flaws in the cut. For applications that need smooth and high-precision cuts, plasma cutting will deliver better results.
- Precision – As with other computer-controlled tools, a CNC plasma cutter offers higher precision than manual cutting because the torch will carefully follow the programmed path. The best human machinists might get close to CNC levels of precision, but the work will take much longer.
- Reasonable cost – The low cost of a plasma cutter may be passed along to clients who pay less for a large and complex cutting job than they would spend at a company that relies on other, less-powerful cutting tools.
- Portability – Many grinding and milling tools are not portable or semi-portable at best. This lack of mobility is acceptable if you intend to bring your workpiece to the machine shop. Sometimes a customer needs a portable milling tool like a CNC milling table with a plasma cutter.
Plasma CNC milling technology offers high-speed cutting at high quality and reasonable cost for most metals. However, these advantages come with minor disadvantages that might discourage someone from buying their own equipment. The cutting process is very loud and comes with exceptionally bright flashes of light as the plasma jet cuts into a workpiece.
Finally, even though the tool may be relatively affordable, the total cost of ownership can be high. In part, that is because of the specialty gas supplies needed. If you have never priced compressed nitrogen or methane, you can see how the cost might be distressingly high. The fumes produced can also be a little hazardous. If you want your own plasma cutter, be sure to ventilate the working area and insist anyone using the device wear eye and ear protection. Programming the controller to produce the right cuts may also be a challenge. Finally, plasma cutting is primarily useful for conductive materials. On a positive note, those disadvantages can be dealt with easily by hiring a CNC machine shop.
The Advantage for Commercial and Industrial Consumers
Those benefits translate into getting quality work done on common metals and common alloys in less time than it would take to mechanically work a piece to create exact shapes with smooth edges. Correcting work that is not high-quality wastes time. The cost of owning and operating machine tools inevitably gets passed on to the machine shop’s customers. Anything that helps them control costs could cause prices to go down. Some milling jobs are best completed on-site, which is not an option with some CNC tools. For example, a plasma cutting table can be relocated to a mine or construction site to make or modify a part.
Plasma Cutting Offers Distinct Advantages
If you need high precision and fast work, a plasma cutter is a viable option to consider for anyone who has cutting projects to complete. And if you need precision work done on a schedule, you can always turn to CNC machine shops. For any individual or business requiring a cutting and milling job, big or small, Hamilton Machine has the tools to handle it. Contact us to learn more about our metal CNC machine capabilities.