TIG welding settings chart
Starting points by metal and thickness, and the diagnostic table for when the puddle is not behaving.
Starting settings by metal and thickness
| Material and thickness | Current type | Typical amperage | Tungsten | Filler diameter |
|---|---|---|---|---|
| Steel, 22 gauge | DCEN | Roughly 20–35 A | 1/16 in | 1/16 in |
| Steel, 1/16 in | DCEN | Roughly 40–70 A | 1/16 in | 1/16 in |
| Steel, 1/8 in | DCEN | Roughly 90–130 A | 3/32 in | 3/32 in |
| Steel, 1/4 in | DCEN | Roughly 150–200 A | 1/8 in | 1/8 in |
| Stainless, 1/16 in | DCEN | Roughly 35–60 A | 1/16 in | 1/16 in |
| Stainless, 1/8 in | DCEN | Roughly 80–120 A | 3/32 in | 3/32 in |
| Aluminum, 1/16 in | AC | Roughly 60–90 A | 3/32 in | 1/16 in |
| Aluminum, 1/8 in | AC | Roughly 110–150 A | 3/32 in | 3/32 in |
| Aluminum, 1/4 in | AC | Roughly 180–225 A | 1/8 in | 1/8 in |
Reading the chart
Amperage is a ceiling, not a setting. With a foot pedal you set the machine's maximum at the figure above and control everything below it with your foot. That is the whole point of the pedal — the amperage a joint wants when cold is not the amperage it wants thirty seconds later.
Aluminum needs more amps than steel at the same thickness, which surprises people given how easily aluminum melts. It conducts heat away from the joint far faster, so you are heating the whole part rather than just the weld area.
Tungsten diameter must suit the current. Too small for the amperage and the tip overheats and spits tungsten into the weld; too large at low amperage and the arc wanders because there is not enough current density to stabilize it.
Filler diameter roughly matches the material thickness for thin work. Rod that is too thick chills the puddle when you dip it; too thin and you are dipping constantly.
Gas flow and post-flow
Flow: 15 to 20 CFH for most work with a standard cup. More is not better — excessive flow becomes turbulent at the cup and draws air into the shield, which produces exactly the contamination you were trying to avoid.
Post-flow: roughly one second per 10 amps as a starting point. Post-flow is gas continuing after the arc stops, protecting the hot weld and the hot tungsten while they cool. Too little and your tungsten oxidizes the instant you release the pedal, turning the tip dull and gray.
A gas lens — a mesh insert that smooths the gas flow — lets you run a longer tungsten stickout with better coverage, and is the most worthwhile early consumable upgrade.
AC settings for aluminum
AC balance — start mid-range. Move toward more cleaning if the puddle looks gray and sluggish, toward more penetration if it is clean but shallow.
AC frequency — higher frequency narrows and stiffens the arc, which helps in fillets and corners. Lower broadens it for wide flat welds.
TIG welders for aluminum covers both in more depth.
Fixing the weld in front of you
| Symptom | Most likely cause | What to change |
|---|---|---|
| Arc wanders or spits | Contaminated tungsten, or grind marks running the wrong way | Regrind lengthwise on a dedicated wheel; check whether you touched the puddle |
| Tungsten turns black or blue after stopping | Insufficient post-flow | Increase post-flow — roughly one second per 10 amps |
| Weld is gray, dull or sooty (aluminum) | Oxide not cleaned, or too little cleaning action | Brush with an aluminum-only stainless brush, increase the cleaning side of AC balance |
| Puddle will not form | Amperage too low, or the part is conducting heat away | Increase amperage; preheat thicker aluminum sections |
| Burning through | Too much heat, or dwelling too long | Back off the pedal, travel faster, use pulse on thin material |
| Bead is wide and flat with shallow penetration | Arc length too long | Shorten the arc to about one tungsten diameter |
| Porosity in the weld | Contaminated metal, or gas coverage lost | Degrease then grind to bright metal; check for drafts and gas leaks |
| Filler rod sticks to the tungsten | Dipping into the wrong part of the puddle | Feed into the leading edge, not the middle, and not against the electrode |
| Weld looks fine but cracks | Wrong filler alloy for the base metal | Match filler to the parent material — ER70S-2 steel, ER308L stainless, ER4043 or ER5356 aluminum |
The three checks before you change a setting
Is the tungsten clean and correctly ground, lengthwise? Is the metal degreased and ground to bright? Is the work clamp attached directly to the workpiece rather than to a bench it is sitting on?
Any one of those being wrong makes settings irrelevant, and all three are faster to check than a setting is to diagnose.
When the chart is right and the bead is not
These numbers get you a puddle. They do not get you a good bead, because four of the five variables that decide a TIG weld are not settings at all — how to get good TIG welds works through tungsten preparation, base metal cleanliness, torch and filler geometry, pedal control and gas coverage in the order they go wrong.
Start with the tungsten. A contaminated or badly ground electrode produces a wandering, spitting arc that feels exactly like a machine fault, and no amperage adjustment on this page will fix it.
What we would buy
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1. The tungsten these settings assume
CK Worldwide 2% lanthanated tungsten electrodes
AC and DC capable, in the three sizes the chart below uses.
The tungsten sizes in the chart below — 1/16, 3/32 and 1/8 inch — are the standard home shop set, and 2% lanthanated covers both AC and DC so one box serves every row.
Tungsten diameter has to suit the amperage: too small for the current and the tip overheats and spits; too large and the arc wanders at low amperage because there is not enough current density to stabilize it.
What works
- Works on AC and DC, so one box covers aluminum and steel and you stop thinking about it
- Contains no thorium, so grinding dust carries no radioactive-material handling question
What does not
- More expensive per electrode than unbranded tungsten of the same designation
- Still needs a dedicated grinding wheel — sharing a wheel with steel contaminates the tip
2. The controls the chart refers to
Eastwood TIG 220 AC/DC
AC balance, AC frequency and pulse all adjustable, plus a 10 amp floor.
A settings chart is only useful on a machine that can be set. Eastwood publishes adjustable AC balance and AC frequency plus pulse frequency, peak on-time and base current, with TIG output of 10 to 220 amps on 240 volts and 10 to 140 amps on 120.
The 10 amp floor matters for the thin-material rows: a machine whose minimum is 20 amps cannot reach the bottom of this chart at all.
What works
- It publishes both supply figures — 10 to 220 A on 240 V and 10 to 140 A on 120 V — so you can size the circuit before you buy instead of after
- Adjustable AC balance and AC frequency plus pulse frequency, peak on-time and base current: the controls that actually change how aluminum behaves
- Flex-head torch with a gas-lens kit, foot pedal, argon regulator/flowmeter and ground clamp are all in the box. Only the gas bottle is extra
- 22.93 lb. Almost nothing else in the AC/DC class is light enough to carry to the work rather than the other way round
What does not
- The 40% duty cycle applies at the full 220 A in AC TIG; the 60% figure is at 179 A. The AlphaTIG publishes 60% at 200 A
- The bundled torch is a WP-17 pattern — widely supported and cheap on consumables, but not a branded premium torch
- Full output needs the 240 V circuit. On 120 V Eastwood publishes 140 A in TIG and 120 A in stick, roughly two-thirds of the machine
- Eastwood publishes one 1/4 in capacity figure for the machine rather than separate steel and aluminum numbers, so there is less to compare on than some rivals give you
Questions people actually ask
What amperage for TIG welding 1/8 inch steel?
Roughly 90 to 130 amps, which fits the common rule of about one amp per thousandth of an inch of thickness.
Set that as the pedal's maximum and control below it with your foot, because the amperage a cold joint wants is not the amperage it wants thirty seconds in.
What gas flow rate for TIG?
Fifteen to twenty cubic feet per hour with a standard cup covers most work.
More is not better — excessive flow becomes turbulent at the cup and draws air into the shield, producing exactly the contamination you were trying to prevent.
Why does my tungsten turn black when I stop?
Insufficient post-flow. Gas has to keep flowing after the arc stops to protect the hot tungsten and weld while they cool.
Roughly one second per 10 amps is a common starting point. Too little and the tip oxidizes the moment you release the pedal.
What size tungsten should I use?
Match it to the amperage: 1/16 inch for low-current thin work, 3/32 inch for general use, 1/8 inch for higher amperage.
Too small for the current and the tip overheats and spits into the weld. Too large at low amperage and the arc wanders.
Which filler rod for which metal?
ER70S-2 for mild steel, ER308L for 304 stainless, and ER4043 or ER5356 for aluminum.
Using the wrong alloy can produce a weld that looks fine and cracks later, which is why matching filler to the parent material is not a detail.
Sources
- American Welding Society — GTAW parameters, electrode selection and filler classifications
- Eastwood — TIG 220 AC/DC (SKU 74010) published specification table: TIG 10–220 A on 240 V and 10–140 A on 120 V, stick 20–180 A, AC TIG duty cycle 40% at 220 A and 60% at 179 A, high-frequency start, 22.93 lb
- Eastwood — TIG 220 AC/DC product overview: adjustable AC waveform, balance and frequency, adjustable pulse (frequency, peak on-time, base current), WP-17F flex-head torch with gas lens kit, foot pedal, argon regulator/flowmeter and adapter cord in the box
- AHP — AlphaTIG 200X published output range and capacities
Read next
- The best TIG welders for stainless steel
Stainless is a DC job with a heat problem — the machines that control heat, and why you can skip AC.
- The best TIG welders for professionals
Duty cycle, parts availability and repeatability — the three things that separate a working machine from a good hobby one.
- TIG welding for beginners
Torch angle, arc length, feeding rod — the order to learn TIG in so it stops feeling impossible.
- AC vs DC TIG: which do you actually need?
What AC output does, why DC cannot weld aluminum, and how to decide before you buy.
- The best TIG welders for aluminum
AC output, balance and frequency are what weld aluminum. Which machines give real control.
- The best TIG welders for beginners
AC/DC machines for a first TIG setup, and why the bundled torch matters as much as the welder.
- Level 3 · TIG: aluminum, stainless, and welds you meant to look like that
TIG is slower, harder and more expensive than wire welding. It is also the only way to weld aluminum properly at home, and the only way to get a bead you would photograph.
Back to Level 3 · TIG, or start over at Find Your Level.
Ryder M.
Ryder M. is the hands-on owner behind Magoo Media Group. He writes Arc & Bead's buying guides and picks every machine on the site. What every recommendation is based on — and what it is not based on — is set out on How We Pick.