ER308L Stainless Wire: MIG & TIG Settings for 304 Stainless Steel
Standard stainless MIG and TIG wire. Runs 40 to 300 amps on DCEP or DCEN, rated for flat, horizontal, vertical up, overhead. Amperage chart by diameter below.
ER308L is the standard solid wire for MIG (GMAW) and TIG (GTAW) welding on 304 and 304L austenitic stainless steel. The L designation means low carbon (0.03% max), which prevents intergranular corrosion in the heat-affected zone. For MIG, it runs with 98% Argon / 2% CO2 or tri-mix shielding gas. For TIG, it uses pure argon. The wire produces clean, bright weld beads with excellent corrosion resistance matching the base metal. This is the most commonly used stainless filler wire in food service, pharmaceutical, dairy, chemical, and architectural applications.
What This Means in Practice
ER308L means: ER (electrode rod, usable as MIG wire or TIG filler) + 308 (308 stainless chemistry) + L (low carbon, 0.03% max). The ER prefix means it works for both MIG and TIG, unlike E-prefix stick rods.
What Amps for ER308L?
| Diameter | Amperage Range |
|---|---|
| .030" (0.8 mm) | 40 - 140A |
| .035" (0.9 mm) | 60 - 200A |
| .045" (1.2 mm) | 100 - 300A |
Amperage by Individual Diameter
.030 ER308L Amperage
Set .030 ER308L to 40 - 140 amps. Run DCEP or DCEN. This is the smallest available size. Best for vertical-up and overhead where you need a small, controllable puddle. Start around 90A.
.035 ER308L Amperage
Set .035 ER308L to 60 - 200 amps. Run DCEP or DCEN. This is the most commonly used ER308L size. Start at 130A for flat work, drop to 60-117A for vertical-up.
.045 ER308L Amperage
Set .045 ER308L to 100 - 300 amps. Run DCEP or DCEN. Largest available diameter. High deposition for flat and horizontal fillet welds on thick plate. Requires 100A minimum to run properly.
ER308L Suitability Scores
How well this electrode matches common applications. Not a quality rating. all AWS-certified electrodes meet their specification.
What Is ER308L Good For?
MIG or TIG welding on 304 and 304L stainless steel. Food processing equipment, kitchen fabrication, dairy piping, chemical tanks, architectural railings, pharmaceutical equipment.
Any application needing stainless filler that matches 304 base metal corrosion resistance.
Where ER308L Falls Short
Only for 304/304L base metal. Do not use on 316 (use ER316L) or dissimilar joints (use ER309L).
MIG on stainless requires tri-mix or 98/2 gas, standard 75/25 Ar/CO2 causes excessive oxidation.
Lower travel speeds than carbon steel MIG due to heat management.
Wire costs significantly more than carbon steel equivalents.
Welding With ER308L
The Arc
Smooth, quiet arc on both MIG and TIG. On MIG with 98/2 Ar/CO2, the spray transfer is clean and stable. On TIG with pure argon, the arc is silent and precise.
Technique
MIG: push at 15 degrees for flatter beads on stainless. Pushing prevents slag contamination in the trailing edge. TIG: standard dab technique with 1/16 or 3/32 rod fed by hand.
The Puddle
Bright, fluid puddle with a glassy surface. Stainless puddles are more reflective than carbon steel. The molten pool holds heat longer, so it stays liquid further behind the arc. Keep moving to avoid overheating.
When It Goes Wrong
If TIG beads turn dark or gray, increase argon flow and check for drafts. If MIG beads show porosity, verify gas mix is 98/2 Ar/CO2, not 75/25. The higher CO2 content in standard MIG gas causes carbon pickup in stainless.
ER308L Size by Material Thickness
| Wire Size | Material Thickness | Application |
|---|---|---|
| 0.030" | 22 ga to 1/8" | Thin stainless sheet and tubing (MIG) |
| 0.035" | 1/8" to 1/4" | Standard stainless MIG fabrication |
| 1/16" | 1/16" to 1/8" | TIG on thin stainless tubing |
What the Spec Sheet Leaves Out
ER308L is the wire version of E308L-16. Use it for TIG and MIG welding on 304 and 304L stainless steel. For food-grade and sanitary applications, TIG with ER308L and back-purged argon is the standard. The weld must stay straw-colored or lighter. Purple or gray heat tint means the chromium oxide layer is compromised and the corrosion resistance is reduced. Shops that weld food-grade stainless polish the welds and passivate with citric acid after fabrication.
Bottom Line
ER308L earns its keep on sheet jobs. The closest alternative is ER309L.
Setup & Safety Reference
How to Store ER308L
Store sealed. Stainless wire can develop surface oxidation affecting feedability. Keep clean.
Shielding Gas for ER308L
| Gas Mix | Common Name | When to Use |
|---|---|---|
| 98% Ar / 2% CO2 | Stainless MIG mix | MIG welding 304/304L stainless. Keeps carbon pickup low. |
| 100% Argon | Argon | TIG welding. Standard for all stainless TIG applications. |
| 90% He / 7.5% Ar / 2.5% CO2 | Tri-mix | MIG welding. Better penetration and wetting on heavier sections. |
Never use 75/25 Ar/CO2 on stainless. Excess CO2 causes carbon pickup and reduces corrosion resistance.
Preheat & Interpass Temperature for ER308L
Preheat is generally not required for austenitic stainless steel. Excessive preheat can cause sensitization and reduce corrosion resistance.
| Base Metal Thickness | Minimum Preheat (°F) |
|---|---|
| all thicknesses | Not required |
Maximum interpass temperature: 350°F
Shielding gas flow rate: 20-30 CFH
Source: AWS D1.6
Wire Feed Speed for ER308L
Use 98/2 Ar/CO2 or tri-mix (90He/7.5Ar/2.5CO2) shielding gas. Stainless wire runs at lower WFS than carbon steel at equivalent amperage.
| Diameter | Amperage | Wire Feed Speed (IPM) |
|---|---|---|
| 0.030" | 60-140A | 200-500 IPM |
| 0.035" | 80-200A | 180-450 IPM |
| 0.045" | 120-280A | 140-350 IPM |
Deposition Rates
| Diameter | Deposition Rate |
|---|---|
| 0.030" | 2-4 lbs/hr |
| 0.035" | 3-5 lbs/hr |
| 0.045" | 4-8 lbs/hr |
Fume Generation
Rating: Low
Typical fume rate: 0.2-0.5 g/min
Solid stainless wire. Low fume but contains hexavalent chromium. Use extraction.
Common Brand Names for ER308L
Look for Lincoln Electric Blue Max 308L at your supplier. 3 companies produce ER308L-classified rods.
| Manufacturer | Product Name | Notes |
|---|---|---|
| Lincoln Electric | Blue Max 308L | |
| Hobart | Hobart 308L | |
| ESAB | OK Autrod 308L |
Full Specs
| Property | Value |
|---|---|
| AWS Classification | ER308L |
| Process | Stainless MIG/TIG (GMAW) |
| Polarity | DCEP, DCEN |
| Positions | flat, horizontal, vertical up, overhead |
| Penetration | medium |
| Coating Type | solid wire |
| Tensile Strength | 75,000 psi |
| Yield Strength | 55,000 psi |
| Elongation | 35% |
| Base Metals | 304 stainless steel, 304L stainless steel, 301 stainless steel, 302 stainless steel |
| Shielding Gas | 98% Ar / 2% CO2, 100% Argon, 90% He / 7.5% Ar / 2.5% CO2 |
| Gas Flow Rate | 20-30 CFH |
| Max Interpass Temp | 350°F |
| AWS Specification | AWS A5.9/A5.9M:2017 (R2022) |
ER308L Questions
Is ER308L for MIG or TIG?
Both. ER308L is used as MIG wire (GMAW) and TIG filler rod (GTAW) for stainless steel. The same alloy composition works for both processes.
What gas for ER308L MIG welding?
Use a tri-mix (90% He, 7.5% Ar, 2.5% CO2) or 98% Ar / 2% CO2 for stainless MIG welding. Pure argon works for TIG. Do not use 75/25 (Ar/CO2) as the high CO2 content causes carbon pickup in stainless.
What is the difference between ER308L and E308L-16?
ER308L is a bare wire for MIG and TIG welding. E308L-16 is a coated stick electrode for SMAW. Same base alloy, different form factors for different processes.
Where to Buy ER308L
As an Amazon Associate, GageRef earns from qualifying purchases. These are affiliate links.
Manufacturer Data Sheets
External links to standards bodies and manufacturers. These leave GageRef.
Reference data only. Verify all settings against manufacturer documentation and the applicable welding code before use. Amperage ranges are starting points that vary by position, fit-up, and material. Welding involves serious injury risks including burns, electric shock, fume exposure, and fire. This site does not replace proper training, certification, or employer safety procedures. See full terms of use.
Data sourced from AWS A5.9/A5.9M. Amperage ranges are approximate starting points. adjust based on position, fit-up, and material thickness. Always follow manufacturer recommendations and applicable codes.