GTAW (TIG) - For manual AC welding, argon is generally preferred because the arc has good stability. On heavier sections, the addition of helium may be considered, and arc penetration will increase significantly; however, gas flow rates must be increased when helium is added.
| Material Thickness | Tungsten, Pure or Zirconiated | Wire Size | Welding Current (Amps) | Arc Voltage | Gas Cup | Argon, cfh |
| 1/2" | 1/4" | 1/4" | 400 - 450 | 25 | 5/8" | 35 |
| 3/8" | 1/4" | 3/16" - 1/4" | 330 - 380 | 15 | 5/8" | 35 |
| 1/4" | 3/16" - 1/4" | 3/16" | 220 - 275 | 15 | 1/2" | 30 |
| 3/16" | 5/32" - 3/16" | 5/32" - 3/16" | 170 - 225 | 15 | 7/16" - 1/2" | 25 |
| 1/8" | 1/8" - 5/32" | 1/8" - 5/32" | 125 - 175 | 15 | 7/16" | 20 |
| 1/16" | 1/16" - 3/32" | 1/16" - 3/32" | 70 - 100 | 15 | 3/8" | 20 |
