At the moment, among the fastest-growing practices in most workshops is plasma cutting. Plasma cutters use plasma to cut through metals and there is plenty of controversy as to how a plasma cutter differs from the normal oxygen cutters.
Plasma is best defined as a stream of charged particles. These particles contain an equal number of positive ions as well as electrons. The particles exhibit the same properties as those of gas but the plasma is not a gas.
This is mainly because plasma is a good conductor of electricity. The best way to think of plasma is a stream of gas that is electrically charged.
Plasma cutters are torches that contain this stream of charged particles. In a plasma cutter, the stream of plasma flows through a very small orifice into a metal. This plasma stream easily melts and blows through a majority of metals.
The arc of the plasma moves from an electrode and attaches to the metal being cut. That means that the metal needs to be an electrical conductor. Metals like copper, titanium, brass, copper, etc. and their alloys meet this criterion.
The 30/70 Ratio
Plasma can alternatively be defined as a heated gas stream. The temperature of the gas is raised so much that it becomes ionized. Ionization means that electrons are mobile from atom to atom.
It is this mobility of ions that enables the plasma arc to cut through metals. Gas is also the only means to remove the molten metal from the surface. Only 30% of the gas is ionized while the remaining 70% is used to remove metal and for cooling.
This is the 30/70 ratio in plasma cutters.
Benefits of a Plasma Cutter
Increased cut quality
The main feature that puts a plasma cutter above a traditional cutter is gas swirling. Plasma cutters have un-ionized gas that is heavier than ionized gas. These gas particles are thrown to the outer side of the plasma stream.
Without the swirling, a cut would be equal on both sides of the metal being cut. However, because of the gas swirling, the arc is evenly distributed on a single side of the cut. This makes the cut much more precise.
Swirling of the arc leads the electrical arc to attach itself evenly to the edge of the metal being cut. The several attachments occasion an even distribution of power on the work surface. Because the power from top to bottom is equal, a squarer side is formed.
This is another factor that is enabled by gas swirling. During the process, the cooler un-ionized particles are flung to the outer side of the swirl. This gas serves to increase cooling in two major areas.
To begin with, the cool swirl forms a protective shield around the nozzle. This prevents the copper nozzle from burning easily, therefore, increasing its lifespan. Secondly, the cooler gas swirls around surfaces that have been cut and cools them faster than traditional cutters.
Faster cutting speeds
The main benefit of using a plasma cutter is the increased cutting speed that it offers. A plasma cutter utilizes electricity while traditional cutters utilize oxygen and fossil fuels. These cutters depend on the rate of combustion of the fossil fuel being used.
Plasma cutters, on the other hand, utilize electricity to cut through metals. Electricity is much faster than the combustion rate of any fossil fuel. A plasma cutter is, in fact, five times faster than a traditional cutter.
The plasma cutter can also cut up to 500 inches of metal per minute. Take a second and test it for yourself and see how it compares to your standard torch kit… Yeah, I know. It won’t.
Faster cutting speeds mean a faster rate of work at your workshop. More work done equals more money. And more money is good.
Wider material cutting range
The main gas ionized by the plasma cutter is nitrogen. Nitrogen is a very neutral gas, therefore, making it more suitable for more metals. The gas commonly used in traditional metal cutters is oxygen, which is generally less neutral.
The plasma can make accurate cuts on a wider range of metal types (read here: cuts links as well as exhausts and pretty much everything else).
The device is also capable of making precise cuts in metals of varying thickness.
It is easier to use
The amount of training required with traditional cutters is quite substantial due to health and safety issues. This is not the same case for a plasma cutter. An amateur with minimal skills can easily operate a plasma cutter with relative ease.
The marginal amount of training required with the device makes it user-friendly.
It is safer than traditional cutters
Traditional metal cutters utilize oxygen stored in tanks. Oxygen is a highly flammable and explosive substance. If any accident, even the slightest one, occurs in such a workshop, substantial loss of life and property could occur.
However, plasma cutters utilize nitrogen tanks. Nitrogen is not explosive and not nearly as flammable as oxygen. This makes a plasma cutter significantly safer to operate than traditional cutters.
The plasma cutter comes in a small package. It is much smaller than the traditional cutters. Some of the plasma cutters are even hand-held devices.
This feature will save you tons of space in your workshop. This space can then be put into other uses.
The device is cost-effective
Plasma cutters are generally more economical to run than traditional cutters. These cutters utilize incredibly less energy than traditional cutters. They can cut through high-strength construction steel with less heat input than traditional cutters.
It can be used underwater
Because it does not depend on combustion but rather on ionization of nitrogen gas, a plasma cutter can be used underwater. I don’t even have to mention how this is an incredible advantage for auto mechanics!
Just imagine for a second… No more acetylene torch problems caused by water and snow dripping from cars!
A plasma cutter is an invaluable tool for any auto mechanics. It saves you space, time, and money. It is a device that every professional mechanic requires in their workshop and I strongly suggest you get one like, yesterday!
As always, drop us a line in the comment box below and let us know if you got yourself a plasma cutter and what you use it for in the shop!
About the author
I’m Tim Miller, an automotive mechanic, and blogger from Denver, Colorado. I’m also the founder of obdadvisor.com, an automotive blog about OBD2 scan tools.
I’ve had over 10 years of experience in car repair and using OBD scanners.
Some of my review articles about car diagnostic tools can be found on my website obdadvisor.com.