Student Material 001: TIG Welding Quick Reference & Parameter Guide
Material ID: U6M3-MAT-001
Purpose: Quick reference for TIG welding parameters, tungsten selection, and technique
Updated: 2026-03-19
TIG Parameter Charts
Mild Steel (DCEN, 100% Argon)
| Thickness |
Tungsten |
Filler |
Amps |
Cup |
Gas (CFH) |
Post-flow |
| 20 ga |
1/16" |
1/16" ER70S-2 |
30-50 |
#5-6 |
15-18 |
5s |
| 16 ga |
3/32" |
1/16" ER70S-2 |
50-80 |
#6-7 |
15-20 |
8s |
| β
" |
3/32" |
3/32" ER70S-2 |
80-120 |
#7-8 |
18-22 |
10s |
| 3/16" |
β
" |
3/32" ER70S-2 |
120-170 |
#8 |
20-25 |
15s |
| ΒΌ" |
β
" |
β
" ER70S-2 |
160-220 |
#8-10 |
20-25 |
20s |
Stainless Steel (DCEN, 100% Argon)
| Thickness |
Tungsten |
Filler |
Amps |
Notes |
| 18 ga |
1/16" |
1/16" ER308L |
35-55 |
Minimize heat input |
| 16 ga |
3/32" |
1/16" ER308L |
50-75 |
Back purge for corrosion resistance |
| β
" |
3/32" |
3/32" ER308L |
75-110 |
Back purge required |
| 3/16" |
3/32" |
3/32" ER308L |
100-150 |
Multi-pass, back purge |
Aluminum (AC, 100% Argon)
| Thickness |
Tungsten |
Filler |
Amps |
Balance |
Frequency |
| 16 ga |
3/32" |
3/32" ER4043 |
60-100 |
65-70% EN |
100-120 Hz |
| β
" |
3/32" |
3/32" ER4043 |
100-150 |
65% EN |
80-120 Hz |
| 3/16" |
β
" |
β
" ER4043 |
140-200 |
60-65% EN |
60-100 Hz |
| ΒΌ" |
β
" |
β
" ER4043 |
180-250 |
60-65% EN |
60-80 Hz |
Tungsten Electrode Quick Reference
| Color Band |
Type |
Polarity |
Best For |
| Green |
Pure (99.5% W) |
AC |
Aluminum |
| Red |
2% Thoriated |
DC |
Steel, stainless (most common) |
| Blue |
2% Lanthanated |
DC and AC |
All-purpose (recommended) |
| Orange |
2% Ceriated |
DC (low amp), AC |
Thin material, precision |
Tungsten Grinding Guide
CORRECT: WRONG:
βββββ taper βββββ€ βββββ taper βββββ€
β² β± β² β±
β² 2-2.5Γ β± β² (cross β±
β² diameter β± β² marks) β±
β² β± β² β±
β² Β· β±β tiny flat β² β±β no flat
β² β β± β² β β±
β²ββ± β²ββ±
Marks run LENGTHWISE Marks run ACROSS
(along electrode axis) (perpendicular β arc wanders)
Technique Reference
Torch & Rod Angles
Direction of travel β
Torch (15-20Β° trailing) Filler rod (15-20Β°)
β β
/ /
/ /
βββββββββββββββββββββββββββββββββββ
β
Weld pool (watch this!)
The Dip-and-Withdraw Rhythm
Step 1: ADVANCE torch β pool moves forward
Step 2: DIP filler into leading edge of pool
Step 3: WITHDRAW filler (stay within gas shield)
Step 4: ADVANCE torch again
Repeat...
Creates: ))))))))))) stacked-dime pattern
START WELDING END (CRATER FILL)
ββββ
β ramp up βββββ steady hold ββ
βββ ramp down
(1-2 seconds) (maintain pool) (2-3 seconds + final dip)
TIG Troubleshooting
| Problem |
Cause |
Fix |
| Tungsten contaminated (gray tip) |
Touched pool or filler rod |
Re-grind tungsten to clean point |
| Arc wanders |
Contaminated tungsten; cross-ground marks |
Re-grind with lengthwise marks |
| Porosity |
Contamination, gas issues |
Clean metal, check gas flow (15-25 CFH) |
| Burn-through |
Too much heat |
Reduce pedal pressure; increase travel speed |
| No penetration |
Too little heat |
Increase pedal pressure; decrease travel speed |
| Gray/black weld surface |
Insufficient gas coverage |
Increase gas flow; check for drafts; use gas lens |
| Weld cracking at end |
No crater fill |
Ramp down pedal slowly, add final filler dip |
| Filler rod oxidized (black) |
Rod withdrawn from gas shield |
Keep rod within 1" of pool at all times |
| Pool floats/falls through |
Aluminum β too much heat |
Reduce amps; travel faster; use heat sink |
| Stainless discolored (back side) |
No back purge |
Add argon back purge for corrosion-critical work |
Pre-Weld TIG Checklist
TUNGSTEN:
[ ] Correct type for material/polarity
[ ] Freshly ground, lengthwise marks
[ ] Correct size for amperage
[ ] Properly seated in collet
MACHINE:
[ ] Polarity: DCEN (steel/SS) or AC (aluminum)
[ ] Max amperage set for material thickness
[ ] Post-flow set: 1 sec per 10 amps
[ ] AC balance and frequency set (aluminum only)
[ ] HF start or lift-arc selected
GAS:
[ ] Argon cylinder open, adequate pressure
[ ] Flow rate: _____ CFH (15-25)
[ ] Gas flows when pedal pressed (verify)
JOINT:
[ ] Surfaces ground to bright metal
[ ] Degreased with acetone
[ ] Fit-up and gap correct
[ ] Tack welds in place
FILLER:
[ ] Correct alloy for base metal
[ ] Correct diameter for material thickness
[ ] Clean (not oxidized or contaminated)
PPE:
[ ] Welding helmet (shade 8-12)
[ ] TIG gloves (thin leather)
[ ] FR clothing β all skin covered
[ ] Respirator
[ ] Welding cap
Post-Flow Duration Rule
POST-FLOW = 1 second per 10 amps of final welding current
Examples:
50A β 5 seconds
100A β 10 seconds
150A β 15 seconds
200A β 20 seconds
Hold the torch over the weld for the ENTIRE duration.
Last Updated: 2026-03-19