TIG Welding

TIG welding offers unmatched control through its manual technique:

Process Fundamentals:
- Tungsten Electrode: Non-consumable, creates arc without melting
- Shielding Gas: 100% argon protects puddle and tungsten
- Filler Rod: Added separately by hand as needed
- Foot Pedal/Torch Control: Varies amperage during welding

Electrode Types:
- Pure Tungsten (Green): AC welding on aluminum, soft tip
- 2% Thoriated (Red): DC welding, excellent arc starts, slightly radioactive
- 2% Ceriated (Gray): DC and AC, non-radioactive alternative
- 2% Lanthanated (Blue): Versatile, good for both AC and DC
- Tri-Mix: Combination of rare earths for all-purpose use

Electrode Preparation:
- DC (Steel, Stainless): Grind to a point, grinding marks parallel to length
- AC (Aluminum): Ball forms naturally, or pre-round the tip
- Diameter matched to amperage (general rule: 1 amp per 0.001" diameter)

Polarity:
- DCEN (DC Electrode Negative): 70% heat at work, deepest penetration, steel/stainless
- DCEP (DC Electrode Positive): 70% heat at electrode, cleaning action, rarely used
- AC: Alternating between polarities, balances penetration and cleaning for aluminum

Current Types:
- DC: Smooth arc, consistent penetration
- AC with Balance Control: Adjust cleaning vs. penetration ratio
- Pulsed DC/AC: Reduce heat input while maintaining penetration

TIG welding demands precise manual coordination:

Body Position and Torch Hold:
- Support your arms for stability
- Hold torch like a pencil, relaxed grip
- Torch angle 15-20° from vertical, pointing in travel direction
- Maintain consistent arc length (approximately electrode diameter)

Filler Rod Technique:
- Hold rod at low angle, nearly parallel to work
- Feed from the leading edge of the puddle
- Dip into puddle, don't drip into arc
- Keep rod tip in gas shield when not feeding

The "Dab" Technique:
1. Establish puddle with arc
2. Add filler to leading edge
3. Move torch forward slightly
4. Repeat: heat, dab, move

Walking the Cup:
Advanced technique for pipe and precision work:
- Rest ceramic cup on workpiece
- Rock side to side while advancing
- Creates consistent, beautiful welds
- Requires practice but produces excellent results

Welding Thin Material:
- Lower amperage, smaller electrode
- Faster travel speed
- Pulse settings reduce heat input
- Backing gas prevents oxidation on backside

Aluminum Specifics:
- AC current with cleaning action
- Higher amperage than steel (aluminum conducts heat)
- Push technique (torch points forward)
- 4043 filler for general use, 5356 for strength

TIG welding handles virtually any weldable metal:

Carbon Steel:
- DCEN polarity
- ER70S-2 or ER70S-6 filler
- Clean thoroughly—TIG is unforgiving of contamination
- Used for precision fabrication, thin sheet, visible welds

Stainless Steel:
- DCEN polarity
- Match filler to base (308L for 304, 316L for 316)
- Purge backside to prevent sugaring
- Lower amperage than carbon steel
- Applications: food equipment, pharmaceutical, architectural

Aluminum:
- AC current with balance control
- 4043 filler (general), 5356 (structural)
- Clean oxide layer immediately before welding
- Use larger tungsten, higher gas flow
- Applications: aerospace, marine, transportation

Exotic Metals:
- Titanium: Extensive shielding required (trailing shield, purge)
- Chromoly: Preheat, post-heat for cracking prevention
- Magnesium: AC current, fire precautions
- Copper: High preheat, silicon bronze filler for dissimilar

Industry Applications:
- Aerospace: Thin skins, critical structures
- Motorsports: Roll cages, headers, fuel cells
- Nuclear: Precision pipe welding
- Semiconductor: Ultra-clean fabrication
- Art/Sculpture: Visible, beautiful welds

TIG welding skills command premium compensation:

Salary Expectations:
- Entry TIG Welder: $45,000-$55,000
- Skilled TIG Welder: $55,000-$75,000
- Specialized (Aerospace, Nuclear): $70,000-$100,000+
- Pipe Welder (6G certified): $80,000-$120,000+

High-Demand Specialties:

Aerospace Welding:
- Thin aluminum and titanium
- AWS D17.1 certification
- Extreme quality requirements
- Background checks, drug testing
- Locations: Seattle, Wichita, Los Angeles

Pipe Welding:
- 6G certification (all positions, fixed pipe)
- Carbon steel, stainless, alloys
- Power plants, refineries, shipyards
- Travel often required, excellent pay

Sanitary/Pharmaceutical:
- Stainless steel tube welding
- Orbital TIG experience valuable
- Purging and cleanliness critical
- ASME BPE standards

Certification Path:
1. Practice fundamentals on various materials
2. Pass plate tests (3G, 4G positions)
3. Progress to pipe (2G, 5G, 6G)
4. Add specialty certifications (aerospace, pressure vessel)
5. Consider CWI for advancement

Tools of the Trade:
- Quality TIG welder (Miller, Lincoln, ESAB)
- Variety of cups, gas lenses, collets
- Tungsten grinder
- Filler rod selection
- Purge equipment for stainless/titanium

Investment in quality equipment pays dividends in weld quality and efficiency.