A Complete Guide to Plasma Cutting: Manual & CNC

Whether you’re a first-time buyer looking for a reliable handheld plasma cutter or a fabrication professional cutting metal every day, plasma cutting is one of the fastest, most versatile and most cost-effective ways to cut conductive metal. This guide covers everything you need to know — from how plasma arc cutting works, to choosing the right manual plasma cutter for your application, understanding gas selection, getting the best cut quality and knowing when a CNC system makes more sense.

What Is Plasma Arc Cutting?

Plasma is the fourth state of matter — a superheated, ionised gas that conducts electricity. In plasma cutting, compressed gas (typically air, nitrogen or oxygen) is forced through a small copper nozzle where it contacts an electrode and ionises into a plasma arc. This arc reaches temperatures exceeding 20,000°C — hot enough to melt through virtually any electrically conductive metal almost instantly.

The process works like this:

1. Compressed gas is fed into the torch
2. An electrical arc ionises the gas into plasma
3. The plasma jet melts the metal at the cut point
4. High-velocity gas flow blows the molten material clear, leaving a clean edge

Unlike oxy-fuel cutting, which relies on a chemical oxidation reaction and only works on mild steel, plasma cutting works on all conductive metals — including stainless steel and aluminium — making it far more versatile in a real fabrication environment.

Key Advantages of Plasma Cutting

• Cuts all electrically conductive metals — mild steel, stainless steel, aluminium, copper, brass, titanium and more
• No preheating required — start cutting immediately, saving significant time on the job
• Excellent cut quality on material thicknesses up to 50mm, with maximum capacity up to 150mm on higher-powered systems
• Significantly faster than oxy-fuel on thin to medium thickness materials
• Narrower kerf than oxy-fuel, with less material waste and less heat-affected zone
• Portable handheld units can be used anywhere with a power supply and compressed air
• Safer than oxy-fuel — no storage of explosive gases required

Manual Plasma Cutting: The Right Tool for Most Fabricators

For the majority of fabrication shops, maintenance teams, construction sites and metalworkers, a manual (handheld) plasma cutter is the right tool. It’s portable, quick to set up, straightforward to operate and capable of cutting everything from thin sheet metal to structural steel plate — all with a single machine that can go wherever the job takes you.

Manual plasma cutting is ideal for:

• Fabrication shops — brackets, frames, base plates, custom components and profile cutting
• Maintenance and repair — removing damaged plate, freeing seized fasteners, cutting out sections for repair
• Construction and structural steel — trimming beams, floor plates and pipe on-site
• Automotive — body panels, chassis work, exhaust fabrication
• Agricultural equipment — repairs and modifications in the field or workshop
• General metalwork — any application where cuts are varied, one-off or need to happen on-site

Choosing the Right Manual Plasma Cutter

The most important factor when choosing a manual plasma cutter is matching the machine’s output amperage to the thickness of material you cut most often. A higher amperage machine cuts thicker material, but also costs more and typically draws more from the power supply. For most workshop and site applications, the answer lies in one of three ranges — light fabrication, mid-range all-rounder or heavy workshop use.

• Material type and thickness — mild steel, stainless steel and aluminium all cut at slightly different speeds. Match the machine’s rated cut capacity to your typical material, not the maximum you might occasionally need.
• Duty cycle — the percentage of time the machine can cut continuously before needing to cool down. For occasional use, a 60% duty cycle is fine. For continuous production cutting, look for higher duty cycles or a more powerful unit with headroom.
• Power supply — most handheld units run on single-phase 230V, making them compatible with a standard workshop or site supply. Some higher-amperage models also offer three-phase input for increased performance.
• Air supply — plasma cutting requires clean, dry compressed air. Moisture in the air supply is the leading cause of poor cut quality and premature consumable wear. Always use a quality inline filter and dryer.
• Portability — if you work on-site or move the machine regularly, weight and handle design matter. Look for an all-weather housing and a machine you can comfortably carry to the job.
• Consumable life — long-life consumables reduce running costs and downtime significantly. Some machines are designed for premium consumable systems that last considerably longer than standard electrodes and tips.

ESAB Cutmaster+ Manual Plasma Cutting for Every Application

The ESAB Cutmaster+ range — built on the heritage of Thermal Dynamics, one of the most trusted names in plasma cutting — offers a complete lineup of manual plasma cutters from light fabrication through to heavy workshop and site use. Every Cutmaster+ shares the same core design principles: honest cut capacity ratings, the industry-leading SL60 1Torch® for ergonomic handling, and long-life Black Series consumables that reduce your running costs.

Cutmaster 30+

Compact and lightweight, the Cutmaster 30+ is the ideal entry-level professional plasma cutter for light fabrication, automotive, HVAC and maintenance work. Runs on standard single-phase 230V — no special power supply needed.

• Pierce / cut capacity: 10mm  |  Max severance: 16mm  |  Output: 30A
• Power: Single-phase 230V with automatic voltage detection
• 4.3” TFT LCD display • SL60 1Torch® with 2T/4T function • Black Series consumables included

View the Cutmaster 30+ ›

Cutmaster 50+

The mid-range all-rounder and the most popular Cutmaster for fabrication shops and trade professionals. With a 25mm cut capacity and portable enough to take to site, it handles the vast majority of professional cutting tasks.

• Pierce / cut capacity: 16mm / 25mm  |  Max severance: 32mm  |  Output: 50A @ 60% duty cycle
• Power: Single-phase or three-phase 400V
• 4.3” TFT LCD display • SL60 1Torch® with 2T/4T function • Built-in 14-pin CNC interface for semi-automated cutting with optional MechPak

View the Cutmaster 50+ ›

Cutmaster 70+

The high-output model for demanding environments — heavy plate, structural steel, construction and industrial maintenance. 70 amps of cutting power in a portable, all-weather package that goes wherever the job takes you.

• Pierce / cut capacity: 20mm / 30mm  |  Max severance: 38mm  |  Output: 70A @ 50% duty cycle
• Power: Single-phase or three-phase 400V
• 4.3” TFT LCD display • SL60 1Torch® with 2T/4T function • Built-in 14-pin CNC interface with voltage divider

View the Cutmaster 70+ ›

Cutmaster+ Series — Technical Specs Comparison

Getting the Best Cut Quality with a Manual Plasma Cutter

With the right technique, a manual plasma cutter produces clean, dross-free cuts that need minimal finishing. The key variables to control are travel speed, standoff distance, air quality and consumable condition.

• Travel speed — this is the most important variable to get right. Moving too slowly causes excessive dross on the underside of the cut and a wide kerf. Moving too quickly produces an incomplete cut or heavy top-edge rounding. The correct speed produces a clean cut with a slight backward angle on the arc. Test on a scrap piece first to find the right speed for your material and amperage setting.
• Torch-to-work distance (standoff) — maintaining the correct standoff is critical for cut quality. Too close and you risk nozzle damage; too far and the arc loses focus, producing a wider, rougher cut. Use a standoff guide or drag-cutting tip where possible for consistent results, particularly on longer cuts.
• Torch angle — keep the torch perpendicular to the work surface for a square cut edge. Even a few degrees of tilt introduces a bevel. If you need a bevelled edge, tilt deliberately and consistently.
• Air quality — moisture, oil or contamination in the compressed air supply degrades cut quality and significantly reduces consumable life. Always use an inline moisture filter and air dryer. This is especially important on-site where compressor air quality is often poor.
• Consumable condition — worn or damaged consumables are the most common cause of poor cut quality. Inspect the electrode and cutting tip regularly and replace them before they fail completely. The Cutmaster Black Series consumables are engineered for extended life, but even high-quality consumables wear over time.
• Cutting direction — the cleaner side of the cut is always to the right of the direction of travel. When laying out a cut, position the piece so the “good side” faces the direction you need.
• Grate cutting mode — when cutting expanded metal or grating, switch to grate cutting mode on the Cutmaster 50+ and 70+. This reduces power when the arc is in open air between strands, significantly extending consumable life.

Gases for Manual Plasma Cutting

Most manual plasma cutters — including the entire Cutmaster range — run on compressed air, which makes them practical and low-cost to operate. Understanding when other gases might be worth considering helps you get the best results across different materials.

Compressed Air

Compressed air is the standard plasma gas for manual cutting and the right choice for the vast majority of applications. It delivers a good balance of cutting speed and cut quality on mild steel, stainless steel and aluminium. The key requirement is clean, dry air — a two-stage inline filter and dryer is the best investment you can make for consistent performance.

• Best for: all materials, all manual cutting applications
• Advantages: no gas cylinders required, lowest running cost, easy to source anywhere
• Considerations: moisture must be removed — a quality inline air dryer and filter is essential, not optional

Nitrogen

Nitrogen produces a cleaner cut edge than compressed air on stainless steel and aluminium, with less oxidation on the cut face. It is sometimes used for manual cutting when cut edge quality on non-ferrous metals is important, for example in food-grade stainless fabrication where discolouration on the cut edge is unacceptable.

• Best for: stainless steel and aluminium where cut edge appearance is critical
• Advantages: reduced edge oxidation, cleaner cut face on non-ferrous metals
• Considerations: requires cylinder supply and management; higher running cost than air

Materials You Can Plasma Cut

Plasma cutting works on any electrically conductive metal. The most commonly cut materials are:

• Mild steel — the easiest and fastest material to plasma cut. All three Cutmaster models handle mild steel across their full cut capacity range with excellent results.
• Stainless steel — cuts cleanly with compressed air or nitrogen. Slightly slower than mild steel at equivalent thickness. For the best edge quality on stainless, use nitrogen if the application requires it.
• Aluminium — plasma cuts aluminium well with compressed air, though cut speed is lower than on mild steel due to aluminium’s higher thermal conductivity. Requires higher amperage than equivalent thickness mild steel.
• Copper and brass — can be plasma cut but the high thermal conductivity makes them more challenging. Reduce travel speed and use fresh consumables.
• Other conductive metals — titanium, cast iron and other conductive alloys can all be plasma cut. Some specialist alloys benefit from specific consumable selections — contact ESAB for guidance.

When Does CNC Plasma Cutting Make More Sense?

A manual plasma cutter is the right tool for the majority of fabrication and site applications. However, if your work regularly involves any of the following, a CNC plasma table is worth considering:

• Repeat parts — if you’re cutting the same profile or shape many times, a CNC system eliminates variability, saves layout time and delivers consistent dimensional accuracy on every part.
• Complex profiles — curves, multi-feature profiles, holes and notches that are difficult to cut accurately by hand are straightforward on a CNC table.
• High volume — if cutting is a production bottleneck, a CNC table running at programmed speeds with nesting optimisation significantly reduces material waste and increases throughput.
• Bolt-quality holes — handheld plasma cannot produce bolt-quality holes. CNC systems with precision hole technology can.

For shops looking for a bridge between manual and full CNC, the Cutmaster 50+ and 70+ both include a pre-installed 14-pin CNC interface. Combined with the optional ESAB MechPak straight-line attachment, they can be used for semi-automated straight-line and circle cutting — a practical step up from freehand cutting without the investment of a full CNC table.

For full CNC plasma cutting, ESAB’s Columbus CNC table range and gantry systems offer scalable solutions for every production environment. See our guide to choosing a CNC plasma cutter.

Plasma Cutting vs Other Cutting Processes

Plasma cutting is the most versatile and cost-effective cutting method for most fabricators. Here’s how it compares to the alternatives:

Getting Started

If you’re ready to choose your next plasma cutter, ESAB’s application specialists are here to help you find the right Cutmaster+ for your application — whether that’s the lightweight, versatile Cutmaster 30+ for light fabrication and site work, the all-round professional Cutmaster 50+ for general workshop and trade use, or the high-output Cutmaster 70+ for demanding heavy fabrication environments.

Cutmaster 30+  |  Cutmaster 50+  |  Cutmaster 70+

Or get in touch with an ESAB specialist to discuss your cutting application and get the right system specified for your needs.