OPERATION
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LIFT ARC IGNITION for TIG Welding
Lift Arc is a form of arc ignition where the machine has voltage on the electrode to only a
few volts, with a current limit of one or two amps (well below the limit that causes metal to
transfer and contamination of the weld or electrode). When the machine detects that the
tungsten has left the surface and a spark is present, it immediately (within microseconds)
increases power, converting the spark to a full arc. It is a simple, safe lower cost
alternative arc ignition process to HF (high frequency) and a superior arc start process to
scratch start.
§4.2.3 TIG Welding Fusion Technique
Manual TIG welding is often considered the most difficult of all
the welding processes. Because the welder must maintain a
short arc length, great care and skill are required to prevent
contact between the electrode and the workpiece. Similar to
Oxygen / Acetylene torch welding, TIG welding normally
requires two hands and in most instances requires the welder
to manually feed a filler wire into the weld pool with one hand while manipulating the
welding torch in the other. However, some welds combining thin materials can be
accomplished without filler metal like edge, corner, and butt joints. This is known as
Fusion welding where the edges of the metal pieces are melted together using only the
heat and arc force.
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