The Harris 308L Stainless Steel TIG GTAW Welding Rod (part number 308LTE0) is a low-carbon austenitic stainless steel filler metal classified ER308L per AWS A5.9/A5.9M. Available in a .030 in (0.76 mm) diameter, 36-inch cut-length format packed in a 10 lb box, this rod is engineered for gas tungsten arc welding (GTAW) of 304, 304L, 308, and 308L base metals — the most widely used stainless steel grades in food processing, pharmaceutical, chemical, and architectural fabrication. The "L" (low-carbon) designation limits carbon content to ≤0.03%, which suppresses carbide precipitation at the heat-affected zone and greatly reduces susceptibility to intergranular corrosion and sensitization. Harris Products Group, a Lincoln Electric company, manufactures this rod under strict lot-release testing, providing certified mechanical properties and composition per heat number traceable back to the melt.
The .030 in diameter is the ideal choice for welding thin-gauge stainless sheet (16–22 gauge), tube, and pipe wall thicknesses down to 0.028 in. Precision TIG work on instrument tubing, hygienic fittings, brewery and dairy equipment, and architectural trim relies on the tight dimensional tolerances and low impurity levels that Harris achieves through controlled wire drawing. The 308L TIG rod is compatible with 100% argon shielding gas (the standard for stainless TIG) as well as argon-helium blends used to increase heat input on thicker sections without sacrificing arc control.
| Attribute | Value |
|---|---|
| AWS Classification | ER308L (AWS A5.9/A5.9M) |
| Harris Part Number | 308LTE0 |
| Diameter | .030 in (0.76 mm) |
| Cut Length | 36 in (914 mm) |
| Package Weight | 10 lb box |
| Carbon Content (max) | 0.03% (low-carbon "L" grade) |
| Chromium Content | 19.5–22.0% |
| Nickel Content | 9.0–11.0% |
| Manganese | 1.0–2.5% |
| Silicon | 0.30–0.65% |
| Phosphorus (max) | 0.03% |
| Sulfur (max) | 0.03% |
| Tensile Strength (as welded) | ≥80,000 psi (551 MPa) |
| Yield Strength (as welded) | ≥57,000 psi (393 MPa) |
| Elongation (as welded) | ≥35% |
| Polarity | DCEN (Direct Current Electrode Negative) |
| Shielding Gas | 100% Argon or Ar/He blends |
| Process | GTAW (TIG) |
| Base Metals | 304, 304L, 308, 308L, 321, 347 stainless steels |
| Country of Origin | USA (Harris Products Group) |
The Harris 308L stainless TIG rod excels across industries where corrosion resistance, cleanliness, and structural integrity in a single-pass or multi-pass weld are non-negotiable:
- Food, Beverage & Dairy Equipment: Sanitary piping, pressure vessels, mixing tanks, CIP (clean-in-place) circuits, and heat exchangers fabricated from 304L or 316L stainless are routinely welded with ER308L. The low carbon content ensures weld zones resist pitting and crevice corrosion when exposed to acidic cleaning agents.
- Pharmaceutical & Biotech: High-purity water systems, fermentation vessels, and autoclave components demand weld metal free of sensitization. The .030 in diameter provides the heat control needed for thin-wall tube-to-fitting joints common in BPE (Bioprocessing Equipment) fabrication.
- Architectural & Decorative Stainless: Handrails, elevator interiors, kitchen equipment, countertops, and signage brackets in 304 or 308 stainless require a filler that polishes out smoothly. The fine .030 diameter allows precise bead placement on visible joints that will be mechanically polished or passivated.
- Chemical Processing: Heat exchangers, reactor vessels, and storage tanks handling dilute acids, brine solutions, and mild caustics benefit from the austenitic deposit with ≥19.5% Cr that provides broad-spectrum corrosion resistance.
- HVAC & Refrigeration: Stainless tubing headers, manifolds, and custom sheet metal in commercial HVAC systems handling moisture-laden or mildly corrosive air streams.
- Shipbuilding & Marine Fabrication: Handrails, ladder assemblies, and seawater piping on commercial vessels and offshore platforms where 304L base metal is specified.
Achieving X-ray-quality stainless TIG welds with the .030 in Harris ER308L rod requires consistent technique and correctly dialed parameters. Follow this setup guidance for optimal results:
Machine Setup: Use a TIG welder capable of DCEN output. Set high-frequency start or lift-arc start. For .030 in wire with thin-gauge sheet, begin at 40–80 amps; for 1/8 in material, you may push to 120–150 amps. Use a foot pedal or hand amperage control where possible — stainless has low thermal conductivity and heat builds quickly. Pulse TIG (e.g., 100 Hz, 30% background, 30% on-time) dramatically improves thin-sheet weld quality by reducing heat input and distortion.
Tungsten: Use a 3/32 in or 1/8 in diameter 2% ceriated or 2% lanthanated tungsten electrode (gold or black band). For .030 in filler on thin material, a sharpened 1/16 in tungsten also works well. Grind tungsten to a sharp point for DCEN stainless welding; do not ball the tip.
Shielding Gas: Use 100% argon at 15–20 CFH (7–9 L/min) through a gas lens assembly (gas lens cup recommended over standard collet body for stainless). An argon/helium blend (75/25 to 50/50) increases arc voltage and heat input — useful for faster travel on heavier sections. For critical joints, back-purge the weld root with 100% argon to prevent root-side oxidation (sugaring). Back-purge flow: 5–10 CFH.
Parameters by Material Thickness:
| Base Metal Thickness | Amperage (DCEN) | Filler Feed | Travel Speed | Shielding Gas Flow |
|---|---|---|---|---|
| 22–18 gauge (0.028–0.050 in) | 20–55 A | Continuous dip, .030 in | 4–7 in/min | 15 CFH Ar |
| 16 gauge (0.063 in) | 55–75 A | Continuous dip, .030 in | 5–8 in/min | 15–18 CFH Ar |
| 1/8 in (0.125 in) | 90–130 A | Continuous dip, .030 or 3/32 in | 4–6 in/min | 18–20 CFH Ar |
| 3/16 in (0.188 in) | 130–170 A | Continuous dip, 3/32 in | 3–5 in/min | 18–22 CFH Ar |
Technique: Feed the rod into the leading edge of the weld pool at a 15–20° angle, keeping the filler in the argon cone at all times to prevent tungsten contamination and oxidation of the rod tip. Use a slight walking-the-cup technique on pipe joints to maintain consistent bead width and fusion. Clean base metal with a stainless wire brush (dedicated to stainless only) and degrease with acetone before welding.
Proper storage of Harris 308L TIG rods ensures full mechanical and corrosion-resistance performance is retained throughout the rod's service life:
- Original Packaging: Store in the original sealed box in a dry location with ambient relative humidity below 50%. Stainless TIG rods are not hydrogen-sensitive in the same way low-hydrogen stick electrodes are, but moisture on the rod surface can cause porosity and poor arc starts.
- Temperature: Maintain storage temperature between 40°F and 120°F (4°C–49°C). Avoid garages or outdoor storage areas subject to wide temperature swings and condensation.
- Contamination Prevention: Never store stainless rods alongside mild steel rods, grinding discs used on carbon steel, or near iron dust sources. Cross-contamination with iron particles causes rust spotting on finished welds and can compromise corrosion resistance.
- Gloves Required: Handle rods with clean cotton or nitrile gloves. Skin oils transfer iron, sodium, and chlorine to the wire surface — all detrimental to corrosion resistance in aggressive environments.
- Opened Box Use: After opening, use within a reasonable period (weeks to months in clean shop environment). Replace cap on box after each use session.
- Identification: Label opened boxes with opening date. Do not mix rod from different lot numbers in the same joint for critical code work — each box carries a certificate of conformance (C/C) traceable to the heat number.
Harris 308L TIG rod works with any commercially available DC TIG/GTAW machine. Common platforms used at WeldingMart include:
- Lincoln Electric Square Wave TIG 200 (K5126-1): Excellent machine for thin stainless sheet work. AC/DC capability with built-in pulse control; ideal for the .030 in rod on 16–22 gauge applications.
- Lincoln Electric Invertec V155-S: Compact DC TIG machine with reliable arc starts; widely used in light fabrication and food-service equipment shops for 308L work.
- Lincoln Electric Aspect 375: Premium multi-process TIG system with advanced pulse/AC control. Overkill for basic 308L work but provides maximum weld quality on complex stainless assemblies.
- Any DC SMAW/GTAW machine with DCEN output: The ER308L rod requires only DC electrode negative — any basic DC TIG power source with high-frequency start works.
Compatible Base Metals:
| Base Metal | Compatibility | Notes |
|---|---|---|
| AISI 304 / 304L | ✅ Primary | Most common stainless; ER308L is the default filler |
| AISI 308 / 308L | ✅ Primary | Direct composition match |
| AISI 321 | ✅ Acceptable | For non-high-temperature service (below 800°F); use 347 rod for elevated temp |
| AISI 347 | ✅ Acceptable | Acceptable for general service; use 347 rod for high-temp stabilized joints |
| AISI 316 / 316L | ⚠️ Check service | ER316L preferred for 316 base metal in chloride environments; 308L acceptable for general service |
| AISI 316 to 304 dissimilar | ✅ Acceptable | 308L bridges both; excellent choice for mixed-metal assemblies |
| Carbon steel (mild steel) | ❌ Not recommended | Use ER309L for dissimilar carbon-to-stainless joints |
Selecting the correct stainless steel TIG filler metal requires matching the filler's chemical composition and mechanical properties to the base metal alloy, service temperature, and weld quality requirements. This section compares Harris ER308L to related classifications and explains why the 0.030 in diameter serves specific applications better than the standard 3/32 in rod.
The three most common austenitic stainless TIG classifications for 304/308 base metal differ primarily in carbon content and silicon level:
- ER308: Standard carbon content (≤0.08% C). Used for general 304SS welding not subjected to sustained temperatures in the 800–1500°F sensitization range. Slightly higher tensile strength than 308L.
- ER308L: Low carbon (≤0.03% C). The standard food-grade and corrosion-critical filler for 304L and 308L base metals. Low carbon prevents sensitization. Required for pressure vessels, food/dairy equipment, pharmaceutical piping.
- ER308LSi: Low carbon plus elevated silicon (0.65–1.00% Si). Provides better weld puddle wetting and bead appearance; slightly lower corrosion resistance than 308L. Common for automated/orbital TIG applications.
For food service, chemical processing, and pressure-code applications, ER308L is the standard choice over ER308.
The 0.030 in (0.76 mm) diameter is a specialty size for ultra-thin-gauge stainless welding:
- 22–24 gauge stainless sheet (0.030–0.025 in): Orbital TIG and hand TIG on refrigeration panels, custom kitchen equipment, and architectural stainless panels. The 0.030 in rod provides proportionally matched filler volume to the thin puddle.
- Orbital TIG on small-bore tubing: 0.5 in to 1.5 in OD instrumentation tubing (0.035–0.049 in wall). Automatic orbital welding heads require small-diameter rod to maintain consistent wire feed and heat balance.
- Precision repair welding: Jewelry-scale stainless components, surgical instrument repair, and micro-fabrication where larger rods add too much filler volume per dip.
Harris ER308L is classified and manufactured to AWS A5.9/A5.9M. When used under a qualified welding procedure specification (WPS), it satisfies P-No. 8 base metal filler requirements per ASME Section IX for austenitic stainless steel pressure applications. AWS D1.6 (Structural Welding Code — Stainless Steel) pre-qualified filler metal tables list ER308L as a pre-qualified filler for Group A (austenitic stainless steel) base metals including 304L, 316L, and 321.
For ER308L on austenitic stainless: maximum interpass temperature is 350°F (176°C). Exceeding interpass temperature promotes carbide precipitation (sensitization) even in L-grade stainless if sustained heat exposure occurs. Monitor with contact pyrometer between passes on multi-pass work.
Q1: What is the difference between ER308 and ER308L TIG rod?
The "L" in ER308L stands for low-carbon. ER308L limits carbon to ≤0.03% versus ≤0.08% in standard ER308. The low carbon content of ER308L prevents sensitization — the precipitation of chromium carbides at grain boundaries that reduces corrosion resistance. For any application where the finished weld will be exposed to corrosive environments or cannot be post-weld annealed, ER308L is strongly preferred over ER308.
Q2: Can I use ER308L rod to weld 304L stainless steel?
Yes. ER308L is the standard filler metal for welding 304L (low-carbon 304) stainless. The matching chemistry and low-carbon specification make it the correct choice for 304L pipe, sheet, tube, and plate in all service conditions including chemical, food-grade, and pharmaceutical environments.
Q3: Why should I use 100% argon with 308L TIG rod?
Argon provides the dense, protective shielding atmosphere stainless TIG welding requires. Carbon dioxide or CO₂-containing mixed gases (used in MIG welding) add carbon to the weld deposit, defeating the purpose of using low-carbon 308L filler. For stainless TIG, always use 100% argon or argon/helium blends — never argon/CO₂ or 75/25 C25.
Q4: What is the correct tungsten for stainless TIG welding?
Use 2% ceriated (grey band) or 2% lanthanated (gold/black band) tungsten for DC stainless TIG welding. These tungsten types provide excellent arc starts and long electrode life on DC current. Do not use pure tungsten (green band) on DC — it is designed for AC aluminum welding. Grind the tungsten to a sharp included angle of 30–45° for precise arc control on stainless.
Q5: Does this rod meet any welding codes?
Harris ER308L meets AWS A5.9/A5.9M (Stainless Steel Bare Electrodes and Rods). It is certified per applicable sections of ASME Section II Part C (SFA-5.9) and suitable for use in code-compliant vessels, piping, and structures fabricated to ASME B31.3, AWS D1.6 (Structural Stainless), and similar standards. Always consult the applicable code and your AWS CWI for specific qualification requirements.
Q6: Can I use ER308L to weld 316 stainless?
For general-service applications (non-chloride environments, moderate temperatures), ER308L is acceptable on 316 or 316L base metal. However, ER316L (which contains 2–3% molybdenum) provides superior pitting corrosion resistance in marine, chloride-rich, and high-temperature environments and is the preferred filler for 316 base metal in demanding service. Consult WPS documentation and the project specification before substituting.
Q7: What diameter TIG rod should I use for thin-gauge stainless?
For 22–18 gauge stainless sheet (0.028–0.050 in), the .030 in (0.76 mm) Harris 308L rod is an excellent choice. Its fine diameter provides precise heat and filler control on thin material, minimizing warpage and burn-through. For heavier gauges (1/8 in and above), step up to 3/32 in (2.38 mm) diameter for faster deposition.