Vol. XXVI · No. 04 • Workshop Almanac
Est. MMXIX
Hobby, farm, or fabrication? The right plasma cutter comes down to cut capacity, amperage, and duty cycle. Price alone tells you little. This guide covers amperage, cut thickness, air supply, and pilot arc. We explain inverter tech too. A good plasma cutter slices steel like a hot knife through butter. Cut steel, stainless, and aluminum clean. Buy for the work you do, not the sticker price.
§ II — Reader’s Manual
Plasma cutters are easy to mis-buy. The headline amperage rarely shows the clean-cut thickness you get. Air, duty cycle, and consumables decide the real feel. Want a clean cut instead of a sputter? Read the fine print. Do not trust the big number alone. Here are the six things we weigh.
Output amperage sets how thick you can cut. Watch the split between clean cut, sever cut, and pierce. The clean-cut number is the honest one. A 40-amp machine handles about 3/8-inch steel with ease. Heavier plate wants 60 to 80 amps. Buy for your thickest regular metal, not the thinnest.
Duty cycle is how long you cut before the machine rests. A 60% duty cycle means six minutes on, four off. Cheap units hide a low duty cycle behind big amps. For long seams and production, a higher duty cycle keeps you moving. Nobody likes waiting on a cool-down.
Plasma needs clean, dry air at the right CFM and PSI. Too little and the arc sputters and eats consumables. Confirm the airflow and pair it with a solid compressor. Add a moisture filter to keep the air dry. Some portable units pack a built-in compressor for the field.
A pilot-arc cutter strikes without touching the metal. That means it cuts painted, rusty, or expanded steel with ease. Contact-start units are simpler and cheaper. But they need clean, bare contact. For rusty farm steel or grating, pilot arc earns its extra cost.
Modern inverter cutters are light and efficient. Many run on standard shop power. Some accept dual-voltage 120V and 240V for flexibility. They hold a stable arc and cost less to run. Old transformer units cannot keep up. For portability and clean cuts, inverter is the standard.
Tips, electrodes, nozzles, and shields all wear out. Those costs add up fast. Pick a brand with cheap, easy-to-find consumables. Choose a torch that is simple to rebuild. A low price with rare parts is a false bargain. Cheap upfront can cost the most to own.
Read the guide. Then close the tab and walk away. Come back tomorrow with fresh eyes. The pick that still feels right after a good sleep is usually the one to buy. Sleep on it. Your wallet will thank you.
§ II — Specimen Pages
§ II — Specimen Pages
Every good pick also means cutters we left off. Below are the ones we stopped recommending. It is not about one brand. These let you down at the workbench. A weak cutter stalls right when the job heats up. Why fight your own tool over a seam? Skip these and cut clean.
A machine rated thick only at sever cut and 20% duty stalls fast. Real jobs need clean-cut and steady duty. Read the clean-cut thickness and duty cycle. Ignore the peak-amp headline.
High-frequency contact units struggle on rust and paint. Expanded metal gives them fits too. Cut farm steel or grating? Skip it for a pilot-arc machine. Match the tool to the metal.
Some units hide their CFM and PSI needs. They will sputter on an undersized compressor. Choose a cutter that states its air needs clearly. No specs, no trust.
A cheap torch with parts you cannot find becomes a paperweight. When the tips run out, so does the tool. Buy a cutter with common, cheap, in-stock consumables. Keep it running for years.
Heavy old transformer units waste power. They are a chore to lug around. A modern inverter cuts better and weighs far less. It runs on standard shop power too. Leave the dinosaur in the past.
Uncertified imports often have sketchy grounding. No thermal protection means shock and fire risk. Choose a cutter with real safety certification. Overheat protection is not optional. Your shop is worth it.
§ IV — Directory
One email, every Sunday. New tool reviews, the best tip of the week, and a single recommendation from the editors. No clutter.