Plasma Torches

A handheld (manual) plasma torch is designed with a handle and trigger, intended for an operator to guide by hand along the cut line. A mechanized torch mounts to a cutting table, CNC gantry, or pipe cutter carriage and is operated by machine motion control. Mechanized torches are typically water-cooled and designed for higher duty cycles and longer continuous operation; handheld torches are air-cooled and optimized for portability and access. Lincoln's FlexCut® line offers both K-H (handheld) and K-M (mechanized) variants within the same cutter family.

No — plasma torches are not generically interchangeable. Each torch is designed with specific electrical connections, gas passage diameters, and pilot arc circuitry for a particular power source. Using the wrong torch on a power source can result in no arc start, overheating, or torch damage. For Lincoln FlexCut® and Tomahawk® plasma cutters, replacement torches and torch leads must be specified for the exact cutter model (e.g., FlexCut® 35, 45, 65, 85, 105, or 125). Confirm the cutter model code before ordering a replacement torch.

The pilot arc is a low-power arc established between the electrode and the constricting nozzle inside the torch before the main cutting arc transfers to the workpiece. It keeps a continuous ionized path ready so the main arc can initiate even when the torch isn't touching a conductive surface. This is critical for piercing painted, rusty, or coated metal, for cutting expanded metal (where the arc repeatedly breaks), and for any application where contact-start TIG-style arc initiation would be impractical. All Lincoln FlexCut® and Tomahawk® torches use pilot arc technology.

For most handheld air plasma operations, the drag cup or standoff tip is placed directly on the workpiece surface — the shield cap spaces the torch at the correct standoff automatically for that consumable set. On mechanized or CNC cutting, the standoff height (typically 1/8 in to 3/16 in above the work surface) is set by a torch height control (THC) that measures arc voltage and adjusts the Z-axis. Cutting too far away reduces cut speed and increases dross; too close can cause the nozzle to contact the workpiece and double-arc. Use the standoff guide specified for your amperage kit.

Double arcing occurs when the main arc transfers from the electrode to the constricting nozzle instead of going directly to the workpiece — or when a secondary arc jumps from the nozzle to the workpiece, bypassing the constricting orifice path. Causes include: worn or damaged nozzle orifice, incorrect standoff height (torch too far from the work), contaminated or low air pressure, moisture in the air supply, or mismatched consumables. Double arcing rapidly destroys the nozzle and electrode. Prevent it by maintaining clean, dry air supply, using correct amperage-rated consumables, and staying within the recommended standoff range.