TIG welding delivers the cleanest, most controlled weld bead of any common arc process — but it also demands the most from the welder. Every variable matters: tungsten type, filler rod, shielding gas, amperage, arc length, torch angle, and travel speed all interact. Get one wrong and you'll see it in the weld. Get them all right and TIG produces results that no other process can match for precision and appearance.

This guide covers everything an Australian tradesperson, engineer, or maintenance professional needs to know to TIG weld confidently — from selecting the right tungsten and filler rod to dialling in settings for aluminium, stainless steel, and mild steel. Whether you're setting up a new machine or troubleshooting an existing process, the answers are here.

TIG welding is known by several names: GTAW (Gas Tungsten Arc Welding) is the formal AWS designation; TIG (Tungsten Inert Gas) is what most Australian tradespeople call it. This guide uses both interchangeably.

What Is TIG Welding?

TIG welding creates an arc between a non-consumable tungsten electrode and the base metal. The arc melts the base metal; a separate filler rod is fed manually by the welder's free hand. A shielding gas — almost always pure argon — protects the weld pool and electrode from atmospheric contamination.

Unlike MIG welding, where the wire electrode is consumed and feeds automatically, TIG keeps the electrode intact. The tungsten merely conducts the arc. This separation of heat source and filler material is what gives TIG its defining characteristic: precise, independent control over heat input and weld deposit.

The result is a narrow heat-affected zone, minimal spatter, excellent fusion on thin material, and a weld profile that requires little or no post-weld grinding. TIG is the preferred process for stainless steel food-grade fabrication, pressure vessel root passes, aerospace components, motorsport fabrication, and any application where weld quality is critical.

The trade-off is speed and skill requirement. TIG is significantly slower than MIG or flux-core. It also requires both hands — one on the torch, one feeding filler rod — plus foot or panel control of amperage, a coordination that takes time to develop. For most production environments, MIG or flux-core wins on efficiency; TIG wins on quality.

Process	Speed	Skill level	Best for	Spatter
TIG / GTAW	Slow	High	Thin metal, high quality, stainless, aluminium	None
MIG / GMAW	Fast	Medium	Production, thicker steel, structural	Low–moderate
Stick / SMAW	Medium	Medium	Outdoors, site work, dirty or rusty metal	High

For a detailed side-by-side comparison of all three processes, see our guide on MIG vs TIG vs Stick welding.

AC vs DC TIG Welding

The choice between AC (alternating current) and DC (direct current) is the most fundamental TIG decision, and it is driven entirely by the base metal being welded.

DC TIG Welding

DC is used for the majority of TIG welding: mild steel, stainless steel, copper, titanium, and most exotic alloys. DC provides a stable, focused arc with good penetration. It generates less heat in the electrode (which runs cooler on DC electrode negative), allowing the tungsten to maintain a sharp point and deliver a precise arc.

DC TIG operates in two polarity configurations:

• DCEN (DC Electrode Negative / straight polarity): Used for almost all DC TIG welding. Approximately two-thirds of arc heat goes into the base metal, one-third into the electrode. Good penetration, stable arc, electrode stays cool.
• DCEP (DC Electrode Positive / reverse polarity): Rarely used for TIG. Heat reverses — most goes into the electrode. The electrode overheats rapidly unless very large. Provides cleaning action but is impractical for most applications.

AC TIG Welding

AC is required for aluminium and magnesium. The reason is the oxide layer. Aluminium immediately forms aluminium oxide (Al₂O₃) when exposed to air. This oxide layer melts at approximately 2,050 °C — far higher than the aluminium beneath it (melting point ~660 °C). If the oxide is not removed, it prevents proper fusion.

The positive half-cycle of AC (electrode positive phase) generates cleaning action — it blasts oxide off the surface through cathodic sputtering. The negative half-cycle provides penetration into the base metal. The balance between these two cycles is adjustable on modern inverter machines.

AC TIG also allows adjustment of arc frequency (Hz). Lower frequency (60–80 Hz) produces a wider, softer arc with more heat input — useful for thick aluminium. Higher frequency (100–200 Hz) concentrates the arc, reduces heat input, and improves control on thin material.

Metal	Current type	Polarity	Reason
Mild steel	DC	DCEN	Good penetration, stable arc
Stainless steel	DC	DCEN	Precise control, low heat input
Aluminium	AC	AC	Oxide cleaning action essential
Magnesium	AC	AC	Oxide cleaning action essential
Copper	DC	DCEN	High conductivity — maximise heat into work
Titanium	DC	DCEN	Clean arc, inert gas trailing shield required
Nickel alloys	DC	DCEN	Low heat input preserves corrosion resistance

TIG Tungsten Electrode Types

Tungsten electrodes are colour-coded by their composition. Choosing the wrong tungsten is one of the most common TIG mistakes — it degrades arc stability, contaminates the weld pool, and burns through electrodes faster than necessary.

2% Thoriated — Red Tip

Red-tipped 2% thoriated tungsten is the most widely used electrode for DC TIG welding. It provides excellent arc starts, strong electron emission, good resistance to contamination, and long electrode life. It holds a sharp point well at high amperages.

The limitation is mild radioactivity. Thorium-232 is a naturally occurring radioactive element. At the concentrations in welding electrodes, the health risk from normal welding use is low, but grinding thoriated tungsten generates radioactive dust. This should be done with a dedicated grinding wheel, with respiratory protection, in a ventilated area, with waste disposed of in accordance with local regulations. Many workshops are moving to non-radioactive alternatives.

Use for: DC TIG on mild steel, stainless steel, copper, and most DC applications.

2% Ceriated — Grey Tip

Grey-tipped 2% ceriated tungsten is a non-radioactive alternative to thoriated. It performs particularly well at lower amperages — excellent arc starts on thin material — and works well on DC for stainless, mild steel, and nickel alloys. For most industrial applications the performance difference compared to thoriated is negligible.

Use for: DC TIG, especially thin-gauge stainless and precision work. A safe, practical replacement for thoriated.

1.5% Lanthanated — Gold Tip

Gold-tipped lanthanated tungsten (also available in a 2% formulation, marked black) is a versatile, non-radioactive electrode that handles both AC and DC. It holds a point well on DC, and on AC it forms a stable, controllable ball — making it the go-to all-rounder for shops running both processes.

Use for: AC and DC TIG. The best single electrode choice if you weld multiple materials on one machine.

Pure Tungsten — Green Tip

Green-tipped pure tungsten is the traditional choice for AC TIG on aluminium. On AC, it forms a rounded ball on the tip — this is normal and desirable. The ball shape stabilises the AC arc. Pure tungsten has lower electron emission than alloyed types, which is acceptable for AC but makes it a poor choice for DC.

On older transformer-based AC TIG machines, pure tungsten was essentially the only option. Modern inverter machines with square-wave AC deliver better results with lanthanated electrodes, which hold a more consistent ball with more current capacity.

Use for: AC TIG on aluminium, particularly with older transformer machines.

E3 — Purple Tip

Purple-tipped E3 electrodes are a modern multi-rare-earth formulation designed as a direct replacement for thoriated tungsten. They are non-radioactive, perform well on both AC and DC, and some welders find they outlast thoriated electrodes in service. Growing in popularity in Australian workshops.

Use for: AC and DC TIG as a drop-in replacement for red thoriated where radiation exposure is a concern.

Colour	Type	AC/DC	Best application	Radioactive?
Red	2% Thoriated	DC	Steel, stainless, general DC	Mildly
Grey	2% Ceriated	DC	Thin stainless, precision DC	No
Gold	1.5% Lanthanated	AC/DC	All-round, aluminium & steel	No
Green	Pure tungsten	AC	Aluminium, transformer machines	No
White	Zirconiated	AC	Heavy aluminium	No
Purple	E3 multi-rare-earth	AC/DC	All-round thoriated replacement	No

Tungsten Diameter Selection

Tungsten diameter is chosen to match the amperage range needed. Using an electrode too small for the amperage causes the tip to melt and contaminate the weld pool; too large and arc starts become difficult.

Tungsten diameter	DC amperage range	AC amperage range
1.0 mm	5–30 A	5–15 A
1.6 mm	10–90 A	20–60 A
2.4 mm	65–175 A	60–120 A
3.2 mm	150–250 A	100–180 A
4.0 mm	200–300 A	150–240 A

For DC TIG, grind the tungsten to a sharp point — typically at a 15–30° included angle. The taper length should be 2–2.5 times the electrode diameter. A small flat blunt at the point reduces the risk of the tip breaking into the weld pool. For AC TIG, allow a rounded ball to form — do not grind to a point for AC work.

TIG Filler Rod Selection by Base Metal

Filler rod selection is as important as tungsten choice. The wrong filler can cause cracking, porosity, poor mechanical properties, or corrosion in service. Match filler to base metal — and note that some applications require a different alloy filler rather than a matching one.

Mild Steel and Carbon Steel

ER70S-2: Triple-deoxidised filler containing silicon, manganese, and zirconium deoxidisers. The best choice for steel that may have surface scale, rust, or mill contamination. More forgiving than ER70S-6 on less-than-perfect base metal.

ER70S-6: The most common mild steel TIG rod in Australian workshops. High silicon and manganese content provides good deoxidation and produces a slightly wider, flatter bead profile. Choose ER70S-6 for clean base metal in general fabrication. Both rods produce a minimum tensile strength of approximately 480 MPa, suitable for most structural mild steel work.

Stainless Steel

Stainless filler rod must match or overmatch the base metal grade. Using the wrong filler can compromise corrosion resistance — particularly in food-grade, marine, or chemical service.

• ER308L: For welding 304 and 304L stainless steel. The most common stainless TIG rod. Low carbon ('L' grade) minimises carbide precipitation in the heat-affected zone.
• ER316L: For welding 316 and 316L stainless. Contains molybdenum for superior chloride corrosion resistance — use this for marine, medical, and chemical applications.
• ER309: For dissimilar metal welds — joining stainless to mild steel, or for cladding mild steel with a stainless surface layer. Not a substitute for 308L when welding 304-to-304.
• ER347: For 321 stainless or high-temperature applications where sensitisation is a concern.

Aluminium

Aluminium filler selection depends on the alloy, the service condition, and whether the finished part will be anodised.

• ER4043: The most widely used aluminium TIG rod. Lower melting point than the base metal — it flows smoothly and is forgiving for less experienced welders. Excellent crack resistance. The weld will anodise grey rather than a matching colour — acceptable for structural use but visible on decorative parts.
• ER5356: Higher strength than 4043 (approximately 260 MPa tensile vs 186 MPa for 4043). Better colour match when anodised. Use for structural or load-bearing aluminium welds. More crack-sensitive — not recommended for 2xxx or 7xxx series alloys.
• ER4047: High silicon content makes it extremely fluid. Used for brazing applications and repairs where very high fluidity is needed.

When in doubt: ER4043 for 6xxx-series aluminium (6061, 6063 — the most common industrial alloys); ER5356 for 5xxx-series (5083, 5086) and where higher strength is specified.

Filler Rod Diameter Selection

Material thickness	Recommended filler diameter
0.5–1.5 mm	1.0–1.6 mm
1.5–3.0 mm	1.6 mm
3.0–6.0 mm	2.4 mm
6.0 mm+	3.2 mm

Filler rods in Bossweld and Safra brands for mild steel, stainless, and aluminium are available in the AIMS TIG welding accessories range.

Shielding Gas for TIG Welding

Shielding gas protects the tungsten electrode and molten weld pool from atmospheric oxygen and nitrogen, which cause oxidation, porosity, and embrittlement. Unlike MIG welding, where gas selection varies widely, TIG welding uses a narrow range of gases.

Pure Argon — The Standard TIG Gas

Pure argon at 99.995% purity (5.0 grade) is the correct shielding gas for the vast majority of TIG welding: mild steel, stainless steel, aluminium, copper, and most alloys. Argon provides a stable arc, good cleaning action on AC, and is the only practical choice for AC TIG on aluminium. Do not use welding-grade argon below 99.995% purity for critical TIG work — lower purity grades can introduce porosity, particularly on stainless and aluminium.

Argon/Helium Blends

Adding helium to argon increases arc temperature and heat input without increasing amperage. Blends of 25–75% helium are used for thick aluminium sections where maximum heat input is needed, copper welding (where thermal conductivity is extremely high), and applications requiring faster travel speeds on thicker material. Helium blends are significantly more expensive than pure argon and are not required for most industrial TIG applications.

What Not to Use

Never use CO₂, argon/CO₂ blends, or argon/oxygen blends for TIG welding. These are MIG/MAG gases. CO₂ and O₂ additions are oxidising — they react with the tungsten electrode, causing rapid degradation and weld contamination. If your gas supply contains anything other than argon (or argon/helium for specific applications), do not use it for TIG.

Gas Flow Rates

Application	Flow rate
Standard TIG (cup size 4–7)	8–12 L/min
Larger cups (size 7–10)	12–18 L/min
Gas lens setups	6–10 L/min
Back-purge for stainless pipe	5–15 L/min

Excessive flow causes turbulence and can draw atmospheric air into the gas stream — more is not always better. Set the minimum flow rate that provides full, unbroken shielding coverage.

TIG Welding Settings: Amperage, Balance, and Frequency

Dialling in TIG settings correctly is the difference between fighting the puddle and controlling it. These are the key adjustments on a modern inverter TIG machine.

Amperage

A widely used starting rule for DC TIG on steel is approximately 1 amp per 0.025 mm (1 thou) of material thickness. In metric terms: roughly 40 amps per millimetre of steel thickness.

Material thickness (mm)	Starting amperage — steel, DC
0.5 mm	20 A
1.0 mm	40 A
1.6 mm	65 A
2.0 mm	80 A
3.0 mm	120 A
4.0 mm	160 A
6.0 mm	200–220 A

Aluminium requires approximately 20–30% more amperage than the same thickness in steel due to its high thermal conductivity. These are starting points — adjust based on joint type, position, preheat, and heat sink conditions. If using a foot pedal, set the panel maximum slightly above your expected working amperage and modulate with your foot throughout the weld.

Pre-flow and Post-flow

Pre-flow: Gas flows for a set time before the arc strikes, purging air from the torch and establishing shielding. Typical setting: 0.3–0.5 seconds.

Post-flow: Gas continues to flow after the arc extinguishes, protecting the hot tungsten and weld pool from oxidation. Set post-flow to at least 8–10 seconds for most work; 15–20 seconds when welding stainless or titanium above 150 A. Cutting post-flow too short will oxidise the tungsten tip, contaminate the electrode, and produce poor arc starts.

Balance Control (AC Only)

Balance control adjusts the proportion of time spent in the electrode-positive (cleaning) vs electrode-negative (penetration) phase of the AC cycle. Relevant only for AC TIG on aluminium.

• 30% EP / 70% EN: Moderate cleaning, more penetration. For thicker aluminium or clean, well-prepared surfaces.
• 50% EP / 50% EN: Balanced. A common starting point for general aluminium work.
• 70% EP / 30% EN: Heavy cleaning — removes thick oxide or anodising. The electrode runs very hot at high EP; do not exceed the tungsten's current rating.

Signs of insufficient cleaning (too much EN): sooty black border around the weld, grey-white oxide lifting, poor fusion at weld toes. Signs of too much EP: tungsten overheats and forms an excessively large ball, potentially contaminating the weld.

AC Frequency

AC frequency adjusts how many times per second the current alternates direction. Most modern inverter TIG machines adjust from 20 Hz to 200 Hz.

• Low frequency (20–60 Hz): Wide, soft arc with high heat input. For thick aluminium where penetration is the priority.
• Mid frequency (80–120 Hz): General-purpose aluminium TIG. Balanced arc shape and heat input.
• High frequency (150–200 Hz): Narrow, concentrated arc. Ideal for thin-gauge aluminium, intricate work, or when minimising distortion is critical.

How to Set Up a TIG Welder Step by Step

Setting up a TIG machine correctly before striking an arc is not optional. These steps apply to most modern inverter TIG machines.

1. Select tungsten and grind correctly. DC (steel/stainless): sharpen to a point, 15–30° included angle, taper 2–2.5× the diameter. AC (aluminium): use lanthanated or pure tungsten — allow it to ball naturally, do not grind to a point.
2. Install tungsten in the torch collet. Ensure collet and collet body match the tungsten diameter. Tighten the back cap so the tungsten is secure without overtightening the ceramic cup.
3. Set tungsten stick-out. Standard cups: 3–6 mm extension beyond the cup rim. Gas lens setups: up to 15–20 mm is achievable without losing shielding coverage.
4. Connect shielding gas. Use 99.995% argon. Open the valve, set regulator to target flow rate. Check for leaks at all hose fittings.
5. Set pre-flow and post-flow. Pre-flow: 0.3–0.5 s. Post-flow: minimum 8 seconds for most work.
6. Select AC or DC. DC DCEN for steel/stainless; AC for aluminium/magnesium.
7. Set amperage. Use the thickness-based starting table. Set foot pedal panel maximum slightly above the working range.
8. For AC: set balance and frequency. Starting point: 30–40% EP, 100 Hz. Adjust after the first test pass.
9. Connect work clamp securely. Direct, clean metal-to-metal contact close to the weld area. A loose or remote clamp causes arc instability.
10. Clean the base metal. Remove oil, paint, mill scale, and oxide with angle grinder, flap disc, or stainless wire brush (dedicated per alloy — never cross-contaminate). Wipe with acetone before welding.
11. Test on scrap first. Strike an arc on scrap of the same material and thickness. Adjust before committing to the actual job.

TIG Welding Aluminium

Aluminium TIG is a skill in itself. The material behaves differently from steel in almost every way: it does not change colour before it melts, it has high thermal conductivity, and its oxide layer must be actively managed. With the right setup and technique, aluminium TIG produces clean, strong welds — but the margin for error is narrower than with steel.

Essential Pre-Weld Preparation

Clean aluminium is non-negotiable. Use a stainless steel wire brush dedicated solely to aluminium — never share with steel, as steel particles embed in the softer aluminium and cause porosity. Brush in one direction only. Wipe with acetone on a clean cloth immediately before welding. Aluminium oxide reforms quickly, so weld within 30 minutes of cleaning where possible.

Settings for Aluminium TIG

• Current: AC
• Tungsten: 1.5% lanthanated (gold) or pure (green) for older machines
• Gas: 100% argon, 99.995% purity
• Balance: Start at 30% EP; increase if surface cleaning is insufficient
• Frequency: 100 Hz for general work; 150–180 Hz for thin sheet
• Amperage: Approximately 50–60 A per mm for 6061 alloy (20–30% above the steel starting rule)
• Filler: ER4043 for general work; ER5356 for strength-critical joints

Technique Notes

Aluminium conducts heat rapidly, so heat buildup across a joint happens faster than with steel. As you progress along the joint, the base metal gets progressively hotter. If using a foot pedal, reduce amperage as you travel — start higher, finish lower.

Keep arc length short: typically 3–5 mm. Long arc lengths on AC cause arc wandering and poor cleaning action. If the arc starts to wander or the cleaning zone becomes irregular, the arc length is too long or the tungsten needs redressing.

Watch for the characteristic "wet" look of the aluminium puddle — when properly molten and ready to accept filler, it appears shiny and fluid. A dull or granular appearance before full fusion indicates insufficient heat or inadequate cleaning action.

Preheating thick aluminium (over 10 mm) to 80–120 °C reduces the risk of lack of fusion. Do not overheat — aluminium softens significantly above 200 °C and loses considerable strength above 300 °C.

TIG Welding Stainless Steel

Stainless steel TIG demands low heat input and precise technique. Excess heat causes distortion (stainless has low thermal conductivity and high expansion coefficient), carbide precipitation (destroying corrosion resistance in the HAZ), and oxidation of the weld. Weld colour tells you immediately whether heat control is adequate.

Settings for Stainless TIG

• Current: DC, DCEN
• Tungsten: 2% ceriated (grey) or 2% thoriated (red); 1.5% lanthanated works well
• Gas: 100% argon, 99.995% purity — both shielding and back-purge
• Amperage: Lower side of the starting range — low heat input is always the target
• Filler: ER308L for 304; ER316L for 316; ER309 for dissimilar metal joints

Back Purging — Non-Negotiable for Critical Work

When TIG welding stainless steel tube, pipe, or any closed section where the reverse side of the weld is enclosed, back purging is essential. Without it, the back bead oxidises — the weld "sugars" and loses corrosion resistance.

Back purge with argon at 5–10 L/min. Seal the ends with purge plugs or tape, leaving a small vent to prevent pressure buildup. Purge until oxygen content drops below 50 ppm — allow the pipe volume to purge 3–4 times over before welding. A weld oxygen analyser confirms readiness; as a practical field check, a correctly purged stainless pipe weld shows gold to light straw colour on the reverse.

Weld Colour as a Quality Indicator

• Silver/bright: excellent — optimal heat, good shielding
• Gold/light straw: acceptable — slight additional heat, adequate shielding
• Blue: elevated heat input — review amperage and travel speed
• Brown/grey: excessive heat or reduced shielding effectiveness
• Black or rough/granular: severely oxidised — inadequate shielding or back purge failure

TIG Welding Mild Steel and Carbon Steel

Mild steel is the most forgiving material for TIG welding. Greater tolerance for heat input variation means less sensitivity to settings than stainless or aluminium. That said, clean preparation still matters — TIG will show porosity and inclusions from contaminated base metal more readily than MIG or Stick, which carry more deoxidisers in the consumable.

Settings for Mild Steel TIG

• Current: DC, DCEN
• Tungsten: 2% thoriated (red), 2% ceriated (grey), or E3 (purple)
• Gas: 100% argon, 99.995% purity
• Filler: ER70S-2 for scale or rust-prone material; ER70S-6 for clean stock
• Amperage: 40 A per mm as a starting rule

When TIG Makes Sense for Steel

TIG on mild steel is slower than MIG — but the right choice when appearance matters, when thin gauge (below 2 mm) makes wire feed difficult, when the joint is complex and spatter is unacceptable, or when the weld is the last operation before a visible surface finish. Exhaust systems, motorcycle frames, hydraulic cylinder components, and precision instrument housings are common applications.

For structural fabrication on thicker mild steel (6 mm+), MIG or Stick will be more productive. For a full process comparison, see our MIG vs TIG vs Stick welding guide.

Common TIG Welding Problems and Fixes

TIG welding problems are almost always traceable to one of three causes: contamination, wrong settings, or poor technique. Here are the most common issues encountered in Australian workshops and their solutions.

Tungsten Contamination

Problem: Tungsten tip melts, rounds off, turns grey or blue, or filler rod accidentally touches the tungsten (dipping the tungsten).
Cause: Amperage too high for tungsten diameter; accidental filler-to-tungsten contact; insufficient post-flow allowing the hot tip to oxidise.
Fix: Remove the tungsten, regrind or break off the contaminated section, and restart. Tungsten contamination deposits tungsten oxide into the weld pool — discard welds made with a contaminated electrode and re-run. Increase post-flow to protect the tip after extinguishing the arc.

Porosity

Problem: Voids or pinholes in the completed weld, visible on the surface or revealed by cutting/grinding.
Cause: Surface contamination (oil, moisture, oxide, paint); moisture in filler rods; insufficient shielding gas coverage; drafts disturbing the gas shield.
Fix: Re-clean base metal with acetone and a dedicated wire brush. Store filler rods capped in a dry location. Check gas flow rate and all hose connections for leaks. Shield the work area from air movement.

Arc Wander on AC

Problem: On aluminium, the arc wanders across the surface rather than focusing on the joint. Cleaning action is uneven.
Cause: Arc length too long; tungsten too small for the amperage; excessive EP balance setting causing tungsten overheating.
Fix: Shorten arc length to 3–5 mm. Move to a larger tungsten if the ball is excessively large. Reduce EP balance setting.

Cracking in Aluminium

Problem: Centreline cracks appear in the weld bead during or after cooling.
Cause: Hot cracking — typically caused by using ER4043 on alloys in the 2xxx or 7xxx series; also caused by a very narrow, deep weld profile with high restraint.
Fix: Identify the base alloy. Some 2xxx and 7xxx alloys cannot be reliably TIG welded without specialist filler and procedure. Use a wider, shallower weld profile. Consider weld sequence to reduce restraint. Fill the crater fully before extinguishing the arc.

Sugaring on Stainless

Problem: The reverse side of the stainless weld shows a rough, black, granular appearance.
Cause: No back purge or inadequate back purge; oxygen content too high on the back side.
Fix: Establish proper argon back purge before welding. Allow the pipe or enclosure to purge fully before striking the arc. Use an oxygen analyser to confirm below 50 ppm O₂ before welding.

Lack of Fusion

Problem: Weld bead sits on top of the base metal without full fusion. Visible as a sharp angle at the weld toe.
Cause: Amperage too low; travel speed too fast; arc length too long; torch angle directing arc away from the joint.
Fix: Increase amperage, slow travel speed, shorten arc length, and direct the torch so the arc acts on the joint centreline and both members equally.

TIG Welding Safety

TIG welding creates several specific hazards that must be managed under Australian WHS legislation and applicable standards. These are the minimum requirements for any workplace where TIG welding is performed.

Welding Fumes

In 2017, the International Agency for Research on Cancer reclassified welding fumes as a Group 1 carcinogen — a confirmed cause of lung cancer in humans. This applies to mild steel welding fumes. Stainless steel welding fumes additionally contain hexavalent chromium and nickel compounds, which carry additional carcinogenic risk.

Under model Work Health and Safety Regulations, employers must control welding fume exposure at the source. The hierarchy of controls applies:

1. Engineering controls: Local exhaust ventilation (LEV) — fume extraction arm or torch-mounted extraction — is the preferred primary control. Capture fume at the source.
2. Administrative controls: Welding rotation, distance from arc, work scheduling.
3. PPE: Respiratory protection (P2 minimum for welding fumes; P3 or powered air-purifying respirator recommended for stainless or confined spaces) when LEV is insufficient.

Natural ventilation alone is not considered adequate control for regular welding operations. Consult Safe Work Australia guidance and your relevant state regulator for current workplace exposure standards.

Eye and Skin Protection

TIG amperage range	Minimum lens shade (AS/NZS 1337.6)
Below 75 A	Shade 9
75–150 A	Shade 10
150–250 A	Shade 11–12
Above 250 A	Shade 13+

Auto-darkening helmets covering shade 9–13 are recommended for TIG work. Bystanders within 5 metres of the arc must be protected by screens or equivalent shielding. Wear long-sleeved, dry leather or fire-resistant cotton — synthetic fibres can melt from arc radiation.

General TIG Safety

• Electrical safety: TIG machines operate at high open-circuit voltages (typically 50–80 V OCV). Never touch the tungsten or work clamp with bare skin when the machine is energised. Do not weld in wet conditions.
• Confined spaces: Argon is heavier than air and displaces oxygen in enclosed spaces. Never use TIG in a confined space without forced ventilation and atmospheric monitoring (oxygen depletion + combustible gas).
• Gas cylinder handling: Secure argon cylinders with a chain or strap to prevent toppling. Never store cylinders horizontally or near heat sources. Transport with the valve protection cap fitted.
• Fire risk: Clear the area of combustibles before welding. Have an appropriate fire extinguisher within reach.

Refer to AS/NZS 2980:2007 (Qualification of welding procedures for welding of steel) and AS/NZS ISO 9606-1 (Qualification testing of welders) for procedural qualification requirements in structural and pressure applications.

Choosing a TIG Welder for Industrial Use

Selecting a TIG welder comes down to four primary decisions: AC/DC capability, inverter technology, amperage range, and duty cycle. In an industrial context, reliability and feature set matter more than initial price.

AC/DC vs DC-Only

If you ever need to weld aluminium, you need an AC/DC machine. DC-only TIG machines are less expensive and work well for steel and stainless, but cannot perform AC TIG. A DC-only machine that also runs Stick gives flexibility for site work and dirty metal. An AC/DC inverter gives the full TIG capability range including aluminium.

Inverter vs Transformer

Modern inverter TIG machines have almost entirely replaced transformer machines for workshop use. Inverters are lighter, more energy-efficient, and offer features impossible on transformer technology: variable AC frequency, adjustable balance control, high-frequency arc start, pre-flow, post-flow, and amperage slope control. Unless a transformer machine is already in service, buy an inverter.

HF Start vs Lift Start

• HF start: Arc initiates without contact via a high-voltage spark. No contamination risk from touching tungsten to work. Required for reliable AC TIG on aluminium.
• Lift start: Tungsten is briefly touched to the work, then lifted. Suitable for DC TIG. Some environments (near CNC machines or sensitive electronics) prohibit HF start due to electromagnetic interference — use lift start in those situations.

Amperage Range and Duty Cycle

For general industrial use, 200 A at 60% duty cycle covers most applications. Duty cycle is the percentage of a 10-minute period the machine can operate at rated output. Check the full duty cycle curve in the spec sheet — a machine rated 200 A at 60% may only deliver 150 A at 100% duty cycle. If you weld continuously on heavy sections, choose a machine with a higher duty cycle at the amperage you regularly use.

AIMS Industrial TIG Welding Range

AIMS stocks Bossweld TIG welders suited to maintenance, fabrication, and light production environments, along with a full range of TIG consumables including filler rods, tungsten electrodes, cups, and gas lenses.

Bossweld TIG Machines

• Bossweld ST 141X: DC TIG/Stick, 140 A output, HF start. Compact and portable — suited to maintenance teams and trade workshops. From $230.74.
• Bossweld ST 145X: DC TIG/Stick, 140 A with adjustable pre-flow, post-flow, and digital display. $313.91.
• Bossweld ST 181X: DC TIG/Stick, 180 A output with higher duty cycle for more sustained use. Available machine-only ($284.39) or as a full bundle with torch, work clamp, and regulator ($415.86).

The full range is available in the AIMS TIG welders collection. For shops requiring AC/DC capability for aluminium welding, contact the AIMS team to discuss current AC/DC inverter options.

TIG Filler Rods and Consumables

AIMS stocks Bossweld and Safra TIG filler rods covering mild steel (ER70S-2, ER70S-6), stainless steel (ER308L, ER316L, ER309), and aluminium (ER4043, ER5356) in 1.6 mm, 2.4 mm, and 3.2 mm diameters. Tungsten electrodes, gas lenses, collets, and TIG cups are also available. The full consumables range is in the AIMS TIG welding accessories collection.

For technical advice on TIG machine selection, tungsten choice, or filler rod specification for your application, contact AIMS Industrial in Sydney. We supply tradespeople, maintenance teams, and engineers across Australia.