Question

why is high - frequency (hf) start the preferred method for initiating a gtaw weld?
a it increases the filler rod feed rate.
b it requires less shielding gas to protect the weld.
c it creates a cleaner start without touching the tungsten to the metal.
d it eliminates the need for a foot pedal or control switch.

Explanation:

GTAW (Gas Tungsten Arc Welding) uses a non-consumable tungsten electrode. HF start initiates the arc without touching tungsten to the workpiece, avoiding tungsten contamination and creating a clean start. Other options are incorrect: it doesn’t increase filler feed rate, doesn’t reduce shielding gas need, and doesn’t eliminate control switches.

Answer:

C. It creates a cleaner start without touching the tungsten to the metal.