We are independent & ad-supported. We may earn a commission for purchases made through our links.
Advertiser Disclosure
Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.
How We Make Money
We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently of our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What is a Plasma Cutter?

By Alison McAdams
Updated May 17, 2024
Our promise to you
WiseGeek is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At WiseGeek, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject-matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

A plasma cutter is a relatively easy-to-use tool to cut steel and other electrically-conductive metals. These cutters work by using a high-voltage electrical arc and a compressed gas, usually air. An electrical arc generated by an internal electrode ionizes gas passing through a nozzle, creating a concentrated arc of plasma at the cutter's tip. The arc's contact with the working surface makes a high heat circuit which melts a section less than 1/16" (1.6mm) wide. The force of the plasma flow then literally blows out the molten area on the work piece, creating a fairly clean cut with little or no slag. The plasma arc travels through the nozzle at a speed of up to 20,000 feet per second, and at temperatures as high as 30,000 degrees Fahrenheit (16,600 Celsius)!

Light, portable plasma cutters use 110 volts with an output of around 12-35 amps. To simplify their use, these machines often feature with on-board air compressors. Larger cutters are 220 volt systems with an output between 50 and 80 amps. Hand-held models can be used to cut any conductive metal up to ½ inch thick (1.25cm) while industrial plasma cutters can cut through 2 inches (5cm) of metal.

One of the advantages of using a plasma cutter is that the surface of the metal outside of the cutting area remains relatively cool; this prevents the warping and paint damage that can occur with other flame cutters. A thin heat affected zone (HAZ) also allows the use of templates for precise curved line cutting. Plasma cuts up to five times faster than traditional torches and does not rely on highly-flammable gases. Many plasma cutters also perform well as gougers and can pierce metal quickly and accurately.

Despite the advantages of plasma cutters, there are some drawbacks. The cutter's electrode and nozzle sometimes require frequent replacement which adds to the cost of operation. Non-conductive materials such as wood or plastic cannot be cut with plasma cutters. Another minor drawback is that the plasma arc typically leaves a 4-6 degree bevel on the cut edge; although this angle is almost invisible on thinner material, it is noticeable on thicker pieces. Gas fuel torches are considered better than plasma cutters for thick steel.

WiseGeek is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.
Discussion Comments
By anon77312 — On Apr 14, 2010

how to calculate the life of nozzle and electrode in plasma cutting?

By hthomas — On May 13, 2008

I have one of the small 220 Tig welders, is it feasible to convert this into a plasma cutter, if so, what would I need?

By anon1156 — On May 17, 2007

I am about to build my own plasma cutter/ welder. I know that input power 230 volts times 45 amps will sort of determine the output power, minus about 10 - 20 percent for transformer losses etc.. Just because the way my transformer is wound, it will have an open secondary voltage of 41 volts, with about over 200 amps. The ac/dc stick welder part is easy to design, but I have no experience with a plasma cutter. The output amperage seems to determine the max cutting thickness. The high freq. starting circuit is easy to make, but what is the minimum voltage that a plasma cutter arc needs? In case you are wondering, the transformer is out of a giant industrial 3 phase welder that put out 600 amps, using just the center coil it works like a single phase transformer, it will not burn out.

WiseGeek, in your inbox

Our latest articles, guides, and more, delivered daily.

WiseGeek, in your inbox

Our latest articles, guides, and more, delivered daily.