Welding Consumables Guide: Electrodes, MIG Wire & TIG Rods

Welding consumables — the electrodes, wires, filler rods, and shielding gases that are used up in the welding process — are not interchangeable. The wrong consumable for the process, base metal, or position produces a weld that either fails to meet specification or fails in service. With dozens of options across four main welding processes, the selection decision can feel opaque, particularly when you are new to a process or moving from one base metal to another.

This guide covers the four main welding processes used in Australian industry and trade: stick (SMAW), MIG (GMAW), gasless flux-core (FCAW), and TIG (GTAW). For each process it explains the consumable classification system, the standard options for common base metals, and the selection decisions that matter in practice. A consolidated selection table, a wire speed and voltage reference chart, and storage guidance round out the guide.

Welding processes overview

Before selecting consumables, the process must be fixed. Each process has a different consumable set, different operating parameters, and different strengths. The four processes covered in this guide are:

Stick / SMAW (Shielded Metal Arc Welding) uses a flux-coated solid electrode (the "rod") that melts into the weld pool while the flux coating generates shielding gas and produces a slag layer that protects the solidifying weld. Stick is versatile, portable, and works well outdoors and on dirty or rusty steel. It produces slag that must be chipped and brushed between passes. Used widely in maintenance, pipeline, and structural welding.

MIG / GMAW (Gas Metal Arc Welding) feeds a continuous solid wire through the torch while an externally supplied shielding gas protects the arc and weld pool. MIG is fast, produces clean welds with minimal spatter on well-prepared material, and is easy to learn for general fabrication on mild steel, stainless, and aluminium. Requires a gas cylinder and regulator.

Gasless MIG / FCAW (Flux Cored Arc Welding) uses a flux-filled tubular wire instead of a solid wire. The flux generates its own shielding, eliminating the need for an external gas cylinder. Suitable for outdoor work and dirty material. Produces slag (like stick) that must be removed between passes. Requires reversed polarity compared to gas MIG — a common setup error.

TIG / GTAW (Gas Tungsten Arc Welding) uses a non-consumable tungsten electrode to create the arc and a separately fed filler rod to add metal to the weld pool. TIG produces the highest quality, most precise welds of any process and can join thin and exotic materials — stainless, aluminium, titanium, copper — but is slow and requires high operator skill. Requires pure argon shielding gas for nearly all applications.

Understanding electrode numbering systems

The AWS (American Welding Society) classification system is used throughout Australia for welding consumables. Learning to read these codes removes the guesswork from consumable selection.

Stick electrodes — E-XXXX

The stick electrode classification follows the format EXXXX:

• E — Electrode
• First two digits — Minimum tensile strength of the weld deposit in ksi (thousands of pounds per square inch). E60XX = 60,000 psi (414 MPa); E70XX = 70,000 psi (483 MPa).
• Third digit — Welding position. 1 = all positions (flat, horizontal, vertical, overhead); 2 = flat and horizontal only; 4 = flat, horizontal, vertical-down, overhead.
• Fourth digit — Flux coating type and recommended current. 3 = rutile (AC/DC); 8 = iron powder, low hydrogen (AC/DC+).

So E6013 = 60 ksi tensile, all positions, rutile coating. E7018 = 70 ksi tensile, all positions, low-hydrogen iron powder coating, DC positive preferred.

MIG wire and TIG filler rods — ER-XXX

MIG wire and TIG filler rod classifications follow the format ERXXX-X:

• E — Electrode
• R — Rod/wire (indicates it can be used as either)
• 70 — Minimum tensile strength in ksi (70,000 psi for mild steel wires)
• S — Solid wire
• -6 — Chemical composition suffix. For mild steel: S-2 = basic deoxidiser; S-6 = high silicon/manganese deoxidiser, most tolerant of mill scale and light rust.

So ER70S-6 = electrode/rod, 70 ksi tensile, solid wire, high deoxidiser content. For stainless and aluminium wires the suffix changes: ER308L (L = low carbon, for stainless 304), ER4043 (aluminium alloy 4043).

Stick electrodes (SMAW)

E6013 — the general-purpose rod

E6013 is the most widely used stick electrode in Australia for general mild steel fabrication and maintenance. Its rutile coating produces a smooth arc, easy slag removal, and good weld appearance. It runs on AC or DC and is forgiving of less-than-perfect fit-up. E6013 is the right choice for light fabrication, farm machinery repairs, sheet metal, automotive, and any application where ease of use and clean appearance matter more than absolute tensile strength. It is not a structural electrode and should not be specified for certified structural joints.

E7018 — the structural rod

E7018 is the low-hydrogen electrode for structural, pressure vessel, and high-strength steel welding. The iron powder, low-hydrogen coating produces a deposit with minimum hydrogen content, reducing the risk of hydrogen-induced cracking — the primary mode of failure in medium and high-strength steels. E7018 has higher tensile strength (70 ksi vs 60 ksi) and superior ductility compared to E6013. It requires DC positive, produces a soft, stable arc, and gives excellent mechanical properties. The critical limitation: the coating absorbs atmospheric moisture rapidly once the sealed container is opened. Rods must be stored in a rod oven at 100–150°C after opening. Rods left out of the oven for more than a few hours should be re-dried or discarded — the hydrogen content they introduce defeats their purpose.

E6010 and E6011 — cellulosic electrodes for penetration

E6010 and E6011 are cellulosic electrodes with a high-cellulose coating that produces a forceful, digging arc with deep penetration and a fast-freezing slag — ideal for root passes on pipe, vertical-up welds, and welding through rust, paint, or mill scale. E6010 requires DC positive; E6011 runs on AC or DC and is the more versatile field electrode where only an AC machine is available. Both require good technique — the fast-freezing slag makes them less forgiving than E6013 for beginners.

Cast iron welding rods

Cast iron cannot be welded with standard mild steel electrodes — the difference in thermal expansion causes cracking as the weld cools. Dedicated cast iron electrodes are required. The two main options are nickel-based electrodes (ENi-CI or ENiFe-CI) for cold repair welding — welding without preheat, with short runs, peening each pass, and allowing slow cooling — and high-nickel electrodes for machined cast iron. Machinable weld deposits require nickel-based filler; the alternative is brazing with bronze rod and a braze-welding technique. For cast iron repair, correct procedure (preheat or buttering technique, short stringer beads, peening) matters as much as electrode choice.

Stainless steel stick electrodes

Stainless steel stick electrodes follow the AWS E3XX-XX system. E308L-16 is for welding 304 stainless to itself; E316L-16 for 316 stainless; E309L-16 for dissimilar joints (stainless to mild steel). The "L" denotes low carbon content — essential for preventing sensitisation (carbide precipitation at grain boundaries) in the heat-affected zone, which causes corrosion. Always specify L-grade electrodes for corrosion-critical applications. The "-16" suffix indicates rutile coating, AC/DC operation.

MIG wire (GMAW)

ER70S-6 — mild and low-alloy steel

ER70S-6 is the standard MIG wire for mild steel and low-alloy steel welding. The high silicon and manganese content (the "-6" designation) makes it more tolerant of light mill scale, rust, and surface contamination than the lower-deoxidiser ER70S-2. It is the correct first choice for general fabrication, structural, automotive, and maintenance welding on mild steel. Available in 0.6, 0.8, 0.9, and 1.0–1.2 mm diameters and in 5 kg, 15 kg, and bulk spools.

Stainless steel MIG wire — ER308L, ER316L, ER309L

Stainless MIG wire follows the same L-grade rule as stick electrodes. ER308L for 304 stainless to itself; ER316L for 316 stainless (higher molybdenum content, better pitting resistance in marine and chemical environments); ER309L for stainless to mild steel dissimilar joints. Stainless MIG requires a specific shielding gas — tri-mix (argon/CO2/helium) or low-CO2 argon blend (98% Ar/2% CO2). High CO2 content causes weld sugaring on stainless and promotes sensitisation.

Aluminium MIG wire — ER4043 and ER5356

ER4043 (4.5–6% silicon) is the most commonly used aluminium MIG wire — excellent fluidity, crack resistance, and easy weld appearance. Suited to 6000-series aluminium alloys (6061, 6063) and casting repairs. ER5356 (5% magnesium) is stronger and better suited to structural applications, marine environments, and joints that will be anodised (ER4043 produces a grey anodised finish; ER5356 produces a closer colour match to base metal). Aluminium MIG requires a spool gun or push-pull system — soft aluminium wire kinks and jams in standard push-only 3-metre torch liners. Shielding gas must be pure argon.

Silicon bronze MIG wire — ERCuSi-A

Silicon bronze MIG wire is used for MIG brazing rather than fusion welding. The low arc energy and low melting point (compared to steel wire) allow thin sheet metal, galvanised steel, and dissimilar material joints (steel to copper, thin coated panels) to be joined with minimal heat distortion and without burning through zinc coatings. Silicon bronze MIG braze is increasingly used in automotive body repair for joining thin-gauge steel panels. It requires pure argon shielding. Note that silicon bronze joints are brazed, not welded — joint design and cleanliness requirements are different from fusion welding.

Hardfacing MIG wire

Hardfacing wires deposit a wear-resistant alloy layer over a mild steel base to extend the service life of components subject to abrasion, impact, or metal-to-metal wear. Common hardfacing alloys include chromium carbide (extreme abrasion, low impact — bucket lips, chutes, screens), chromium-manganese (moderate abrasion with impact — crusher hammers, mixer blades), and tool steel alloys for dies and cutting edges. Hardfacing wire is almost always tubular flux-cored wire run without shielding gas (self-shielded) or with CO2. The deposit is typically not machinable — it is ground or EDM-cut if a precise surface is required.

Wire diameter and speed/voltage reference

Wire diameter selection is the first parameter decision in MIG setup. Finer wire runs at lower amperage (suited to thin material and precision work); coarser wire deposits metal faster at higher amperage (suited to thick plate and structural work). The general guide:

• 0.6 mm — thin sheet, 0.5–1.5 mm material. Auto body, HVAC, light gauge fabrication.
• 0.8 mm — general fabrication, 1.5–6 mm material. The most common workshop diameter.
• 0.9 mm — structural and medium-heavy fabrication, 4–10 mm material.
• 1.0–1.2 mm — heavy plate, 10 mm+. High-amperage machines, production welding.

Wire feed speed and voltage are interdependent — faster wire feed requires higher voltage to maintain arc stability. The table below gives starting-point settings for ER70S-6 on mild steel with C25 shielding gas (75% Ar / 25% CO2). These are starting points — dial in from here based on machine, torch length, and actual material condition.

If the arc is harsh and spitting, voltage is too low for the wire feed speed. If the wire is pushing back against the workpiece with a popping sound, voltage is too high or wire feed speed is too slow. For aluminium, use the same diameter guide but increase wire feed speed by 20–30% for equivalent deposit rate.

Gasless MIG wire (FCAW) vs gas-shielded MIG

Gasless MIG wire — correctly called self-shielded FCAW (Flux Cored Arc Welding) — is a tubular wire with flux packed inside. The flux generates shielding as it burns, eliminating the need for an external gas cylinder. It is widely used in Australia for outdoor construction, rural and farm repair, and any situation where carrying a gas bottle is impractical. Understanding its differences from gas MIG is critical — several setup and technique parameters are the opposite of gas MIG, and these mistakes cause most gasless welding failures.

When to use gasless MIG wire

Gasless is the right choice when welding outdoors where wind would disperse shielding gas; when portability rules out a gas bottle; or when welding dirty, rusty, or painted steel where the robust flux shielding is more forgiving than a gas-dependent arc. The trade-off is a slag layer that must be chipped and wire-brushed between passes, more spatter than gas MIG, and a weld bead appearance that is less clean than gas-shielded. Gasless wire is limited to mild and low-alloy steel — there is no viable gasless wire for stainless steel or aluminium. People who search for "gasless stainless MIG wire" or "gasless aluminium MIG wire" are looking for a product that does not exist in any practical form. These materials require shielding gas.

Gasless MIG technique — drag, don't push

Gas MIG uses a push or slight push angle — the torch leans away from the direction of travel, pushing the arc ahead of the weld pool. Gasless MIG uses the opposite: a drag (pull) technique, with the torch angled back toward the completed weld, dragging the arc across the parent metal. The memory rule from the forum world applies: "if there's slag, you drag" — the same drag technique used for stick electrodes applies to all flux-producing wires.

Pushing a gasless weld tends to trap slag in the weld pool, producing inclusions and a rough surface. Common gasless porosity causes beyond polarity errors include: too high voltage for the wire feed speed; torch held too far from the workpiece (too long a stickout); wind disrupting the flux shielding; or dirty base metal with oil, heavy rust scale, or paint.

Shielding gas selection

Shielding gas choice directly affects penetration profile, arc stability, spatter level, and weld appearance. The options are not interchangeable — using the wrong gas for the process or base metal produces poor results or weld defects.

CO2 (pure carbon dioxide)

The lowest-cost shielding gas for MIG welding mild steel. Provides deep penetration and good fusion but produces significantly more spatter than argon-mix gases, and the arc is harsher. Suitable for production environments where spatter and appearance are secondary to penetration and cost. Not suitable for stainless steel or aluminium.

C25 (75% argon / 25% CO2)

The most common general-purpose MIG shielding gas in Australian workshops. Provides a stable arc, moderate penetration, acceptable spatter, and good weld appearance on mild and low-alloy steel. The balance of argon and CO2 suits most general fabrication and structural work. This is the correct default gas for ER70S-6 wire on mild steel.

Pure argon

Required for MIG welding aluminium — CO2 causes poor fusion and weld porosity on aluminium. Also the standard shielding gas for all TIG welding (steel, stainless, aluminium, titanium, copper). Pure argon produces a smooth, stable TIG arc with minimal contamination of the tungsten. For aluminium TIG over 6 mm thickness, adding up to 25% helium increases heat input without sacrificing arc stability.

Tri-mix and low-CO2 argon blends for stainless

MIG welding stainless steel requires a shielding gas with very low CO2 content to prevent sensitisation of the weld heat-affected zone. Standard options are tri-mix (argon/helium/CO2, often 90/7.5/2.5) or a 98% argon / 2% CO2 blend. High CO2 content (C25 gas) causes weld sugaring on the root side of stainless and promotes carbide precipitation in the heat-affected zone, reducing corrosion resistance. Never use pure CO2 on stainless steel.

TIG filler rods

TIG filler rods follow the same ER-XXX classification system as MIG wire. They are supplied as straight cut lengths (typically 1 metre) in 1.6, 2.4, and 3.2 mm diameters. Diameter selection follows the same principle as MIG wire — match diameter to material thickness and amperage range. The key selections by material:

Mild and low-alloy steel

ER70S-2 is the preferred TIG filler rod for mild steel — slightly different from MIG wire in that it contains additional deoxidisers (titanium, zirconium, aluminium) for cleaner welds on less-than-perfect base metal. ER70S-6 can also be used for TIG on mild steel. Both require DC straight polarity (DCEN) with pure argon shielding.

Stainless steel

ER308L for 304 stainless; ER316L for 316 stainless (marine, chemical environments); ER309L for dissimilar joints (stainless to mild). The L designation (low carbon) is essential for corrosion-critical applications. Run on DCEN with pure argon. Back-purge the root side of any stainless pipe or tube weld with argon to prevent root-side oxidation (sugaring).

Aluminium

ER4043 for most aluminium TIG applications — excellent crack resistance, flows well, good colour match after anodising in natural finish. ER5356 for structural aluminium, marine, and applications requiring maximum strength or where the finished part will be anodised (better colour match than ER4043 under hard anodise). Aluminium TIG requires AC current (alternating current), which provides the cathodic cleaning action to break up the aluminium oxide layer. Pure argon shielding.

Silicon bronze — brazing and dissimilar materials

ERCuSi-A silicon bronze TIG rod is used for TIG brazing of thin steel, copper, and dissimilar material joints. Low heat input, no zinc burn-off on galvanised steel. The same applications as silicon bronze MIG wire but with the precision and control of TIG. Run on DCEN with pure argon.

Nickel alloys and Inconel

ERNiCr-3 (Inconel 82) is used for TIG welding Inconel, high-temperature alloys, and for buttering dissimilar joints between stainless and carbon steel in high-temperature applications (power generation, petrochemical). High cost — only specified where the base metal demands it.

TIG tungsten electrodes

TIG tungsten electrodes are non-consumable — they create the arc but do not melt into the weld pool. However, they erode over time and must be ground or replaced. The correct tungsten type depends on the current type (DC or AC) and the base metal.

2% Lanthanated — gold or blue band (WL20)

The modern preferred tungsten for DC TIG welding of steel, stainless, titanium, and most industrial applications. Excellent arc stability at low amperage, long electrode life, easy arc starting. Runs with a pointed tip maintained by grinding (a sharper point concentrates the arc for precision; a larger included angle spreads the arc for broader penetration). Suitable for DC welding only — not for AC aluminium welding.

Pure tungsten — green band (EWP)

Pure tungsten is the traditional choice for AC welding of aluminium and magnesium. AC current causes the tungsten tip to form a rounded ball (the "balled" tip) during welding — this is normal and correct for AC. The balled tip helps direct the cleaning action of AC into the base metal. Pure tungsten should not be ground to a point — the ball forms naturally. Becoming less common as zirconiated tungsten offers better performance for AC applications.

Zirconiated — white band (EWZr-8)

Zirconiated tungsten is the premium choice for AC aluminium welding. It holds a cleaner ball tip than pure tungsten under AC, offers better arc stability, and is more resistant to contamination. Increasingly the preferred option for aluminium TIG in production environments.

2% Thoriated — red band (EWTh-2)

Thoriated tungsten offers excellent arc stability and long life on DC applications. However, thorium is a mildly radioactive element — thoriated tungsten produces radioactive dust when ground and must be ground in a ventilated area with dust collection, with the grinding residue disposed of appropriately. Most Australian industry has transitioned to 2% lanthanated tungsten, which offers equivalent performance without radioactivity. Thoriated is still available and used but is not recommended for new setups.

Tungsten tip preparation

For DC welding (steel, stainless, titanium): grind the tungsten to a pointed tip, with the grinding marks running along the length of the electrode (not circumferentially). An included angle of 30° (a fine point) concentrates the arc for precision work; 60–90° for higher amperage broader welds. For AC aluminium welding: start with a clean cut end and allow the ball to form under the AC arc. Do not grind a point for AC applications.

Consumable selection by base metal

Note on galvanised steel: Zinc vapour released when welding galvanised steel causes metal fume fever — an acute illness with flu-like symptoms. Always weld galvanised steel with forced ventilation or respiratory protection. MIG brazing with silicon bronze wire produces far less zinc vapour than fusion welding and is preferred for thin-gauge galvanised panel work.

Storage and handling of welding consumables

Low-hydrogen stick electrodes (E7018, E7016)

Low-hydrogen electrodes absorb atmospheric moisture within hours of the sealed container being opened. Absorbed moisture produces hydrogen in the arc, causing hydrogen-induced cracking — a delayed defect that can appear hours or days after welding. Correct storage:

• Keep sealed until immediately before use.
• Once opened, store in a heated rod oven at 100–150°C. Never leave low-hydrogen rods on the bench overnight.
• Rods exposed to atmosphere for more than 4–8 hours should be re-dried at 300–350°C for 1 hour before use, or discarded.
• Rods that have been wet (dropped in water, stored in humid conditions without an oven) should be discarded — re-drying wet rods is not reliable.

General-purpose stick electrodes (E6013)

Rutile-coated electrodes like E6013 are less sensitive to moisture but should still be stored in a sealed, dry container. Coating damage from rough handling reduces arc stability and slag detachment — handle rods by the flux end, not the bare metal end.

MIG wire

MIG wire corrodes if left exposed in humid environments. Store spools in a sealed plastic bag or airtight container with a desiccant when not in use, particularly in coastal or tropical environments. Corroded MIG wire produces an erratic arc, increased spatter, and liner blockage from rust particles. Wire that has developed visible surface rust should be replaced — do not attempt to clean it.

TIG filler rods

TIG filler rods for steel and stainless should be kept clean and dry. Any oil, grease, or moisture on the rod will contaminate the weld pool immediately — TIG offers no flux protection. Handle rods with clean gloves. Aluminium TIG rods should be cleaned with acetone before use if they have been stored for extended periods — the thin aluminium oxide layer on the surface thickens with time and can cause porosity. Keep all TIG filler rods in their original tube or a clean sealed container.

Shielding gas cylinders

Cylinders should be stored upright, secured against a wall or in a cylinder cage. Keep valve protectors in place when not connected. Argon and CO2 are asphyxiation hazards in enclosed spaces — always ensure adequate ventilation. Check regulator gauges before starting any significant job — running out of gas mid-weld on stainless or aluminium produces an immediate contaminated weld that must be cut out and redone.

Frequently asked questions

What welding rod should I use for general mild steel welding?

E6013 is the go-to all-round stick electrode for mild steel — easy to use, stable arc, suitable for AC or DC, works well in all positions, forgiving on less-than-perfect fit-up and surface condition. E7018 is the step up for structural work, pressure vessels, and any application requiring certified welds with higher tensile strength and a low-hydrogen deposit. For general maintenance, fabrication, and farm repair, E6013 is correct. For load-bearing structural joints to code, specify E7018.

What is the difference between E6013 and E7018 electrodes?

The first two digits indicate minimum tensile strength in ksi: E6013 = 60,000 psi, E7018 = 70,000 psi. E6013 uses a rutile coating — easy arc start, smooth slag, suitable for thin material and general fabrication on AC or DC. E7018 has a low-hydrogen iron powder coating — higher strength, more ductile weld deposit, superior mechanical properties, suited to structural and pressure vessel work on DC positive. The critical difference in practice: E7018 must be stored in a rod oven after opening — moisture absorption destroys its low-hydrogen property and defeats the purpose of specifying it.

What does ER70S-6 mean for MIG wire?

E = electrode, R = rod/wire, 70 = 70,000 psi minimum tensile strength, S = solid wire, 6 = high silicon and manganese deoxidiser content. The "-6" formulation makes the wire more tolerant of mill scale and light surface rust compared to ER70S-2. ER70S-6 is the standard choice for MIG welding mild and low-alloy steel in general fabrication and maintenance.

What is the correct polarity for gasless MIG wire?

Gasless flux-core MIG wire (FCAW) requires DCEN — DC Electrode Negative, also called straight polarity. This means the torch lead connects to the negative terminal and the earth lead to the positive terminal. This is the opposite of gas MIG (GMAW), which runs DCEP (torch to positive). Welding gasless wire on the gas MIG polarity setting produces porosity, excessive spatter, and poor fusion. On machines with clearly labelled polarity switches this is a settings change; on others the torch and earth leads must be physically swapped. If your gasless weld quality is poor despite correct wire and technique, check polarity first — it is the most common setup error.

When should I use gasless MIG wire instead of gas-shielded MIG?

Gasless is the right choice when welding outdoors where wind would disperse shielding gas; when you do not have a gas cylinder or portability matters; or when welding dirty, rusty, or painted steel where the flux shielding is more forgiving. Gasless produces more spatter and slag than gas MIG, and the weld appearance is generally less clean. For workshop welding on prepared material, gas-shielded MIG gives a cleaner, faster result. Remember: gasless wire runs on DCEN (electrode negative) and requires a drag technique — both are opposite to gas MIG.

What shielding gas should I use for MIG welding steel?

C25 (75% argon / 25% CO2) is the most common all-purpose mix for MIG welding mild steel — good penetration, stable arc, moderate spatter. Pure CO2 gives deeper penetration and lower gas cost but produces more spatter. For stainless steel, use 98% Ar / 2% CO2 or an argon/helium/CO2 tri-mix — never use C25 or pure CO2 on stainless, as the high CO2 content promotes sensitisation and root-side weld sugaring.

Can I MIG weld aluminium without shielding gas?

No. Aluminium MIG welding requires pure argon shielding gas — there is no practical self-shielded (gasless) wire for aluminium welding. Products marketed as "gasless aluminium MIG wire" do not produce weld-grade results and are not suitable for structural or load-bearing applications. Aluminium MIG also requires a spool gun or push-pull system (soft aluminium wire jams in standard steel-liner push torches), and correct drive roll selection (U-groove rolls, no knurling). If you do not have a gas bottle and need to join aluminium, TIG brazing with a propane torch and aluminium brazing rod is an alternative for light-duty joints.

Which MIG wire do I use for welding aluminium?

ER4043 is the most common choice — good fluidity, crack resistant, easy to weld, suits 6000-series alloys (6061, 6063), and works well for casting repairs. ER5356 is the choice for structural aluminium, marine environments, and parts that will be hard-anodised (it gives a better colour match under anodising than ER4043). Both require pure argon shielding and a spool gun or push-pull system.

What MIG wire diameter should I use?

0.6 mm for thin sheet (0.5–1.5 mm material). 0.8 mm for general fabrication (1.5–6 mm) — the most common all-round choice in an Australian workshop. 0.9 mm for structural and medium-heavy work (4–10 mm). 1.0–1.2 mm for heavy plate on a high-amperage machine. Finer wire gives better control and lower heat input on thin material; coarser wire deposits metal faster on thick plate.

Why does my MIG wire keep jamming in the torch?

The most common causes are: liner clogged with metal swarf and dust — remove the liner, blow it out with compressed air, or replace it. Wire bird-nesting at the drive rolls — check drive roll pressure (too tight crushes wire; too loose slips). Incorrect liner diameter for the wire. For aluminium wire, a standard steel liner and push-only system almost always causes jamming — use a Teflon-lined torch with a spool gun or push-pull system for aluminium.

What is a low-hydrogen electrode and why does it matter?

Low-hydrogen electrodes (E7018, E7016, E7015) have a coating formulated to produce minimal hydrogen in the arc atmosphere. Hydrogen dissolved in the solidifying weld metal diffuses to areas of high stress and can cause hydrogen-induced cracking — a serious defect in medium and high-strength steels that may not appear until hours or days after welding. Low-hydrogen rods are mandatory for certified structural welds on medium and high-strength steel. They must be kept in a sealed container or rod oven at 100–150°C after opening — rods exposed to atmosphere lose their low-hydrogen status within hours.

What tungsten do I use for TIG welding steel vs aluminium?

For DC TIG welding of steel, stainless, and titanium: 2% lanthanated tungsten (gold or blue band) — excellent arc stability, long electrode life, sharp point maintained by grinding. Weld on DCEN (electrode negative) with pure argon. For AC TIG welding of aluminium: pure tungsten (green band) or zirconiated (white band) — the AC arc forms a natural ball at the tip, which is correct. Do not grind these to a point. Thoriated tungsten (red band) works well on DC but produces mildly radioactive grinding dust — 2% lanthanated is the modern alternative with equivalent performance and no radioactivity concern.

AIMS Industrial stocks welding consumables including stick electrodes, MIG wire (mild steel, stainless, aluminium), gasless flux-core wire, TIG filler rods, and tungsten electrodes. For help matching the right consumable to your process, base metal, and application, contact our team.