Better known as the fourth state of matter, plasma is a heated gas flow that forms when either compressed air or gas comes in contact with an electrode. This makes the gas ionise and create plasma. Well, plasma cutting would be the melting process in which a welding machine uses the capabilities of plasma together with a power source in order to make an electric arc and cut a metal object.
Plasma cutters are rather powerful machines but what makes for an even better solution is a CNC plasma cutter. What makes it better is the use of a computer to automate a big part of the cutting process. With a plasma table cutter, all you have to do is prepare the workplace and give instructions to the cutter.
What Matters in a CNC Plasma Cutter
Ease of Use
The CNC part or the computerised numerical control system of a plasma table cutter is what affects the ease of use of this type of equipment. While a computer is used with a low-end cutter, a high-end plasma cutting table relies on a much more complicated system. But this complexity doesn't necessarily make it more difficult to use the cutter, it just makes it more capable in high-production environments.
Software
What can make your experience with CNC plasma cutting machines simpler, is the use of the right type of software. You'll need to get to know a plasma cutter's CAD or computer-assisted drawing software as well as its CAM or computer-assisted machining software. The former lets you draw out the shape of the cut while the latter helps you deal with more technical stuff like kerf width and tolerances.
Table Size
The size of the cutter's table is going to determine how large of a workpiece you'll be able to work on. While cutters with larger tables are more versatile, they are not necessarily as fitting when you want to save space. While you shouldn't get the smallest cutter available you also shouldn't go overboard.
Torch Height Control
There are three modes that torch height control operates and these are cut height, pierce height and the voltage setting of the torch. Pierce height can help prolong the lifespan of the torch's tip while cut height helps avoid any collisions between the plate and the tip. The voltage setting regulates the amount of power that the torch is being fed.
Fume Control System
With a proper fume control system as part of your CNC plasma cutting table, you can expect to stay safe from all those hazardous fumes being generated when cutting metal. While entry-level cutters have a water table, it's not as efficient at extracting fumes as a separate system.
Power Output
The number of amps the torch comes with determines its power output. The higher the power output of a plasma cutter the thicker the metal it can cut through. But keep in mind that CNC plasma cutting machines with a high amp rating will also consume more power as a result of that.
Filter
There are 3 types of air filters a plasma table cutter can have and those are basic, roll and in-line filters. A basic filter is exactly what you'd expect it to be, a filter that is capable of keeping your cutter working in a safe manner when making small cuts.
If you want a more capable air filter then go with a roll air filter which is able to provide better air filtration but it's not self-draining. This means you have to replace it from time to time depending on how much you use your table cutter.
An in-line filter is a rather useful solution in high-humidity environments since it closes and opens to prevent moisture from coming through. But other than that, an in-line filter is not capable of providing continuous airflow.
Shields
In the same way, there are 3 types of air filters, and there are 3 types of shields too. A plasma cutter shield is going to allow you to do different types of cutting. For instance, when it comes to contact cutting you need a shield that will allow you to put the tip of the gun against the surface of the metal workpiece.
A shield for gouging will let you remove a piece of metal without having to actually cut through a workpiece while. A shield for stand-off cutting will help you cut through a workpiece with some space left between the tip and the workpiece.
Air Pressure
Air pressure goes together with the number of amps you're using. If your CNC plasma cutter uses a high number of amps, the air pressure regulator should also be cranked up more so that enough air passes through to make the cutter generate an arc. A solid starting air pressure of any cutter is 75 PSI or 5 bar.
2T vs 4T
The difference between 2T or two touch and 4T or four touch mode is that the latter requires fewer steps in order to keep the arc ignited. Despite the name, 2T is less convenient since it makes you hold down the button down while cutting while 4T mode lets you do so by just clicking once to turn it on and then once again to turn it off.
