A plasma cutter is a welding machine that operates by sending an electric arc through a gas--oxygen, nitrogen, argon, or shop air--passing through a constricted opening. The combination of high-pressured gas flow and the electric arc results in a “plasma jet.” The jet quickly reaches temperatures as high as 40,000° F., enabling it to cut through a metal workpiece and blow away the molten material. The plasma cutter also directs the gas around the perimeter of the cutting area to shield the cut.
Today you will find pilot arc technology in most high-quality plasma cutters. This feature allows cutting without touching the tip to the metal workpiece, resulting in improved cutting quality and longer life on consumables. Pilot arcs are ideal when cutting through painted, rusted, or rough surfaces, producing minimal slag.
A hand-held plasma cutting torch is often used to quickly cut through sheet metal, plates, bolts, pipes, and a long list of other purposes. They are excellent for removing faulty welds or back-gouging weld joints. And while you can use a hand torch to cut shapes from a steel plate, it might not be as accurate or have the quality edges to meet metal fabrication requirements.
Which Plasma Cutter Is Right For You?
However, some reasonably-priced plasma cutters are designed to be used with CNC machines, guaranteeing accuracy and fine cutting edges. In addition to accuracy, here are a few more questions you will need to answer before making a final decision on a plasma machine:
- Are you cutting thick metal?
- Do you need a portable unit?
- How often will you be using the cutter?
- Are you willing to adapt your power outlets for your cutter?
- Are you planning on using a generator with your plasma cutter?
- Will your electrical current fluctuate?
As you weigh your plasma cutter options, these questions will help you narrow down your choices. You will discover that some brands have the standard features you need, and others will offer a plasma cutter and welder in one machine—an ideal option for the person who only needs the cutter on occasion.