What's inside
As an Amazon Associate I earn from qualifying purchases. This post may contain affiliate links at no extra cost to you.
Why expanded metal stalls a plasma cutter
Expanded metal is a tougher test than a solid sheet of the same thickness. The strands and openings interrupt the arc, so the torch may lose its transfer as it crosses a gap, then need to relight on the next strand. A cutter that handles a steady plate cut may sputter, stop, or leave rough, partly severed strands on mesh.
That makes duty cycle, restart behavior, and torch control as important as the advertised maximum thickness. A high amperage number alone won’t guarantee clean cuts through expanded metal. The right choice depends on the metal’s strand thickness, how much you need to cut, and whether you have a suitable air supply and electrical circuit.
What to look for when buying
Amperage and cut rating: Match the cutter to the thickest strand, not the overall thickness of the mesh. For light expanded steel with strands around 1/16 to 1/8 inch thick, a 30- to 40-amp machine is often enough. Heavier strands or long production runs call for more capacity. Manufacturer cut ratings vary, and “maximum cut” typically means a slower, less tidy cut than a machine’s recommended working capacity.
Duty cycle: Duty cycle states how long a cutter can operate within a 10-minute period at a stated output. For example, a 35% duty cycle at 40 amps means about 3.5 minutes of arc-on time, followed by cooling time. On a small repair, that may be fine. For a fence panel or repeated fabrication work, a higher duty cycle helps avoid thermal shutdowns.
Air and power: Many shop cutters require clean, dry compressed air; check the required pressure and airflow against your compressor’s delivered capacity, not just its tank size. Also verify the input voltage and circuit amperage. Some machines accept both 120V and 240V, but usually deliver more cutting power on 240V. Undersized power or wet, oily air can cause weak cuts and short consumable life.
Cutter types compared
| Type | Best fit for expanded metal | Main trade-off |
|---|---|---|
| Compact 120V cutter | Occasional repairs and light mesh with thin strands | Lower output and more cooling pauses; limited headroom on thicker material |
| Dual-voltage 30–40A cutter | Most home shops cutting mild-steel mesh and small plate | Requires a suitable 240V circuit to reach its stronger performance |
| Higher-output 50–60A cutter | Thicker strands, longer cuts, or regular fabrication | Higher cost and greater demands on power and compressed air |
For occasional light work, a compact 120V plasma cutter can be a sensible budget choice. Don’t buy one expecting it to cut heavy mesh quickly all afternoon. A dual-voltage 40-amp plasma cutter gives most home users more flexibility, provided the shop has the circuit and air supply it needs.
Keep the cut moving without losing the arc
Use a steady travel speed and keep the torch at the distance specified in its manual. Moving too slowly builds heat and can warp thin strands; moving too quickly leaves bridges of uncut metal. A drag shield or standoff guide can help maintain a consistent torch position, but don’t force a consumable onto the work if the torch isn’t designed for contact cutting.
On mesh with large openings, a straight continuous pass may repeatedly extinguish the arc. Try cutting along a strand direction, and plan the path to cross as few gaps as practical. If the machine offers a suitable restart or pilot-arc mode, it may help with interrupted cuts, though no setting can fully compensate for a cutter that lacks enough output. Test on scrap from the same sheet before committing to a finished panel.
Check consumables if the arc starts cutting erratically. A worn or damaged electrode or nozzle can cause a wandering arc, poor cut quality, or difficulty restarting. Replace parts as a set when the manual recommends it, and inspect the air filter and moisture trap. Low air pressure at the torch—not merely at the compressor—can lead to sputtering and excessive consumable wear.
When a cheaper cutter is enough
A basic cutter is reasonable if you’re trimming one panel now and then, the strands are thin, and you can tolerate slower progress and occasional stops. Paying extra for a higher-output machine is hard to justify if it will spend most of its life stored away. But for repeated cuts, thick strands, or work where a stalled arc ruins a long edge, extra amperage and duty cycle are useful capacity, not just headline numbers.
Before buying, compare the machine’s rated output at the voltage you can actually supply, its duty cycle at that output, and its air requirements. If the listing gives only a maximum thickness and omits working cut capacity or duty cycle, treat that as missing information. A 240V cutter in the 50-amp class is a better fit for regular heavier work, but only if the circuit and compressor are up to the task.
Safe setup matters
Expanded metal has sharp edges and can shift as strands are severed. Clamp the panel securely on a stable, nonflammable surface, and keep sparks away from fuel, solvents, and other combustible material. Wear a properly rated welding helmet, gloves, long sleeves, and eye protection when handling the mesh. Plasma cutting also produces intense light, fumes, and hot slag, so provide effective ventilation and follow the cutter manufacturer’s safety instructions.
Finally, inspect both sides of the cut: slag can cling to the underside even when the top edge looks clean. Let the work cool before handling it, then deburr the edge before fitting or welding. Choosing enough cutter for the strand thickness, keeping the air dry, and testing the cut path on scrap are the most reliable ways to avoid repeated stalls.