Electrode comparison
ER70S-6 vs E71T-11
ER70S-6 needs a gas bottle and shelter but welds clean; E71T-11 needs neither and works outdoors, at the cost of spatter, smoke and slag.
ER70S-6 vs E71T-11 at a glance
| ER70S-6 | E71T-11 | |
|---|---|---|
| AWS specification | AWS A5.18/A5.18M | AWS A5.20/A5.20M |
| Process | MIG (GMAW) | Flux-Cored (FCAW) |
| Form | Solid wire | Tubular wire |
| Tensile strength (min) | 70 ksi | 70 ksi |
| Yield strength (min) | 58 ksi | 58 ksi |
| Elongation (min) | 22% | 20% |
| Impact toughness | 20 ft·lb at -20 °F (27 J at -29 °C) | Not required by AWS A5.20 for the -11 classification |
| Polarity | DCEP | DCEN |
| Positions | Flat, Horizontal, Vertical, Overhead | Flat, Horizontal, Vertical, Overhead |
| Penetration | Medium, varies strongly with gas and transfer mode | Medium |
| Deposition rate | High, continuous feed with no stub loss | High |
| Coating / core | None — bare solid wire, often copper coated for feedability and contact | Self-shielding flux core inside a mild steel sheath |
| Slag | None; silicon islands float to the surface and are brushed off | Heavy and fast-freezing; peels off but leaves more to clean than gas-shielded wire |
| Shielding gas | 75% argon / 25% CO2 (C25) | None — self-shielded |
| Storage | Keep spools dry and covered. Bare wire rusts, and rusty wire means porosity and feed problems. | Keep dry and sealed. Self-shielded flux core is hygroscopic and damp wire is the usual cause of porosity on gasless machines. |
| Primary use | General fabrication and shop welding on carbon steel | Outdoor and windy-site repair welding |
Which should you use?
This is the decision every small MIG machine owner faces. ER70S-6 with 75/25 gas gives a clean, tidy, low-spatter weld with no slag — provided you are indoors and the steel is reasonably clean. E71T-11 needs no gas at all, runs DCEN instead of DCEP, tolerates wind, and handles rust and paint better, but it spatters, smokes, leaves slag to chip, has no impact toughness requirement and is usually limited by the manufacturer to material under about 1/2 in. Indoors on clean steel, solid wire. Outdoors or on dirty steel, gasless.
Choose ER70S-6 when
- Indoor shop work on clean steel
- Sheet metal and thin material
- Welds where appearance matters
- Lower consumable cost over time
Choose E71T-11 when
- Outdoor and windy conditions
- No gas bottle available or practical
- Rusty, painted or weathered steel
- Field and farm repair
Amperage compared
| Diameter | ER70S-6 | E71T-11 |
|---|---|---|
| 0.023 in (0.6 mm) | 30–90 A | — |
| 0.030 in (0.8 mm) | 50–180 A | 50–150 A |
| 0.035 in (0.9 mm) | 70–220 A | 70–200 A |
| 0.045 in (1.2 mm) | 120–320 A | 125–260 A |
Ranges are typical starting points. Diameters listed for only one electrode are shown as — for the other.
ER70S-6 vs E71T-11 — common questions
Do I need to change polarity between them?
Yes, and this is the mistake that catches most people. Solid ER70S-6 runs DCEP; self-shielded E71T-11 runs DCEN. On most small machines that means swapping the gun and work leads at the terminals inside the case.
Why does my gasless weld look so much worse?
Some of that is inherent — self-shielded wire spatters more and leaves slag. The rest is usually reversed polarity, too short a stickout, pushing instead of dragging the gun, or damp wire.
Which is better for thick steel?
Neither is ideal. E71T-11 is usually limited to under about 1/2 in by the manufacturer, and solid wire in short-circuit transfer risks cold lap. For real plate work, use gas-shielded E71T-1 or stick with E7018.
Full specifications
ER70S-6
AWS A5.18/A5.18M
ER70S-6 is the default solid MIG wire for carbon steel — high silicon and manganese let it weld over mill scale and light rust with good wetting.
E71T-11
AWS A5.20/A5.20M
E71T-11 is self-shielded flux-cored wire — no gas bottle, runs DCEN, and works in wind, which makes it the standard gasless wire for small machines and outdoor repair.