Unlike oxy-fuel cutting, which relies on oxidising steel, plasma works on stainless, aluminium, copper and painted or rusty material.
Cut capacity is quoted two ways: severance (the thickest material it will cut through at all) and clean cut (the thickness it will cut at good quality). Clean cut is typically 50-60% of severance, so a machine quoted at 3/4 in severance cuts about 3/8 to 1/2 in cleanly.
Input power limits real-world performance. A 120 V plasma cutter is convenient but limited to roughly 1/4 to 3/8 in; 240 V machines reach 1/2 in and beyond. Duty cycle at rated output determines how long you can cut before the machine needs to cool.
Built-in air compressors make a cutter portable but limit cut quality; separate compressed air supply gives cleaner, drier air and better consumable life. Moisture in the air supply is the most common cause of short consumable life and poor cut quality.
