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.
What we would buy
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
PrimeWeld TIG225X
AC balance, AC frequency and pulse all adjustable, plus 10 to 225 amps.
A settings chart is only useful on a machine that can be set. PrimeWeld publishes adjustable AC balance, AC frequency and pulse, with 10 to 225 amps across 110 and 220 volts.
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 ships with a genuine CK Worldwide CK17 torch — the part everyone else upgrades to, included
- Auto voltage detection means no switch to set wrong
- Adjustable AC balance, AC frequency and pulse — the three controls that actually change how aluminum behaves
What does not
- 40% duty cycle at maximum is lower than the AlphaTIG's 60%, though both are far beyond hobby demand
- Costs meaningfully more than the AlphaTIG; the CK torch accounts for a good part of it
- Like every AC/DC inverter in this class it is heavy and wants a permanent bench spot
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
Read next
- 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.