E71T-11 is the standard self-shielded flux-cored wire for hobby welders, farm shops, and field repairs. It generates its own shielding gas from the flux core, so you don’t need a gas bottle, regulator, or hose. Just spool it up, set the polarity to DCEN (straight polarity), and weld. It runs in all positions, handles multi-pass welds, and produces 71,000 PSI tensile strength deposits that exceed most mild steel base metal requirements. For anyone running a small wire-feed welder without gas, E71T-11 is the go-to wire.
The classification breaks down: E = electrode, 7 = 70,000 PSI minimum tensile (rounded to “71” by convention), 1 = all-position, T = tubular (flux-cored), 11 = self-shielded, DCEN, multi-pass approved.
AWS Classification
E71T-11 is classified under AWS A5.20 (carbon steel electrodes for FCAW):
- E = Electrode
- 7 = 70,000 PSI minimum tensile class
- 1 = All-position
- T = Tubular (flux-cored)
- 11 = Self-shielded, DCEN, multi-pass capable
The “-11” suffix is the critical identifier. It tells you three things: no external shielding gas needed, the wire runs on DCEN, and multi-pass welding is approved. This separates it from E71T-GS (single-pass, limited positions) and E71T-1 (gas-shielded, DCEP).
Mechanical Properties
| Property | AWS A5.20 Minimum | Typical Value |
|---|---|---|
| Tensile Strength | 70,000 PSI (480 MPa) | 76,000 - 85,000 PSI |
| Yield Strength | 58,000 PSI (400 MPa) | 62,000 - 70,000 PSI |
| Elongation (2") | 22% min | 22 - 28% |
| CVN Impact (-20F) | 20 ft-lbs | 25 - 40 ft-lbs |
These properties meet AWS D1.1 requirements for structural welding. In practice, E71T-11 is rarely used on code-governed structural work because gas-shielded wires (E71T-1, E71T-1C) produce cleaner deposits with better impact values. But for non-code fabrication, farm repairs, and general shop work, E71T-11’s mechanical properties are more than adequate.
Wire Sizes and Settings
| Wire Size | Material Thickness | Voltage | Wire Feed (IPM) | Polarity |
|---|---|---|---|---|
| 0.030" | 20 ga - 3/16" | 15 - 19 | 120 - 300 | DCEN |
| 0.035" | 16 ga - 1/4" | 16 - 22 | 150 - 350 | DCEN |
| 0.045" | 3/16" - 3/8"+ | 18 - 28 | 150 - 400 | DCEN |
Wire size selection: 0.030" is the standard for 110V machines and light material. 0.035" is the all-around size for 220V welders doing general fabrication. 0.045" is for production work on heavier material with 250A+ power sources. Most hobby and farm welders should start with 0.030" or 0.035".
CTWD (stickout): Self-shielded flux-core runs with longer stickout than solid MIG wire. Use 3/4" to 1" from contact tip to work for 0.030" and 0.035" wire. For 0.045", extend to 3/4" to 1-1/4". The longer stickout allows the flux to heat up and begin generating shielding gas before it reaches the arc.
Setting Up for E71T-11
Switching from solid MIG wire to E71T-11 requires specific changes:
1. Polarity: Switch to DCEN (DC electrode negative). On most MIG welders, this means swapping the gun lead and work lead at the terminal block, or flipping a polarity switch if the machine has one. The owner’s manual shows the procedure for your specific machine.
2. Drive rolls: Switch to knurled (V-knurl) drive rolls. Smooth V-groove rolls used for solid wire will slip on the softer tubular wire, and flat knurled rolls crush it. V-knurl rolls grip without deforming the wire tube.
3. Tension: Back off drive roll tension. Flux-cored wire is softer than solid wire and crushes easily. Tighten just enough to feed consistently. If the wire birdnests (tangles at the drive rolls), the tension is too tight, not too loose.
4. Gas: Turn off the shielding gas. Disconnect the gas hose from the gun if possible, or at minimum turn the gas off at the regulator. Leaving gas flowing interferes with the self-shielding flux chemistry. Some machines have a “flux” or “no gas” setting that disables the gas solenoid.
5. Gun liner: The standard liner for solid wire works for flux-core in most cases. If you’re running 0.045" wire, verify the liner ID matches. Some shops dedicate a separate gun liner to flux-core to avoid cross-contamination.
How Self-Shielding Works
The flux core in E71T-11 contains several components that generate shielding when the wire melts in the arc:
Gas-forming compounds: Calcium carbonate and other carbonates decompose at arc temperature to produce CO2 gas that displaces atmospheric nitrogen and oxygen from the weld zone.
Deoxidizers: Aluminum, titanium, and magnesium compounds scavenge residual oxygen in the weld pool, preventing porosity.
Slag-forming compounds: Rutile (TiO2) and fluoride compounds create a slag blanket that covers the weld bead as it solidifies, protecting the cooling metal from atmospheric contamination.
The combined gas/slag shielding system is why E71T-11 works in wind up to 30-35 mph, where MIG with external shielding gas would produce porous welds at wind speeds above 5-8 mph. This wind resistance is the primary advantage of self-shielded wire for outdoor and field work.
Technique
E71T-11 runs with a drag technique (pulling the gun), not a push technique.
Travel angle: 15-25 degrees drag from perpendicular. Dragging allows the slag to flow behind the arc and cover the solidifying bead. Pushing causes the slag to roll ahead of the arc, creating slag inclusions and poor shielding.
Travel speed: Moderate. The slag should trail the puddle by about 1/2 inch. If the slag catches the arc, you’re going too slow. If the bead is narrow and ropy with incomplete fill, you’re going too fast.
Contact tip to work distance (CTWD): 3/4" to 1" for 0.030"-0.035" wire. This is longer than MIG wire’s typical 3/8"-1/2" stickout. The extended stickout helps the flux preheat and begin decomposing before it reaches the arc.
Vertical up: Use a slight weave or triangle pattern, pausing at each toe. Keep wire feed speed at the low end of the range and maintain the drag angle. If the puddle sags, you’re running too hot or moving too slow.
Spatter management: E71T-11 produces more spatter than solid MIG wire. Anti-spatter spray on the workpiece makes cleanup easier. Keep the nozzle clean of spatter buildup, which disrupts gas flow and can cause feeding problems.
Slag Removal
Self-shielded flux-core produces a thick, glassy slag that must be removed between passes on multi-pass welds. The slag is harder and more tenacious than E7018 stick electrode slag. Use a chipping hammer followed by a wire brush.
On single-pass fillets, the slag often self-releases as the bead cools, popping off in sheets. If it doesn’t release, a few taps with a chipping hammer cracks it free. Grinding the slag off works but wears flap discs fast due to the glassy, abrasive nature of the slag.
Inter-pass cleaning is mandatory. Welding over slag inclusions creates voids and discontinuities in the finished joint. Chip, brush, and visually inspect every pass before running the next one.
E71T-11 vs. Solid MIG Wire
The trade-offs between E71T-11 and ER70S-6 solid wire with shielding gas:
E71T-11 advantages:
- No gas bottle, regulator, or hose required
- Works outdoors in wind
- Simpler setup for portable and occasional use
- Higher deposition rate at the same wire feed speed (the flux adds mass)
Solid MIG wire advantages:
- Cleaner beads with less spatter
- No slag to remove
- Better appearance on finished welds
- Lower consumable cost per pound of deposited metal
- Quieter, smoother arc
The practical choice: If you have gas available and work indoors, solid MIG wire produces better results with less post-weld cleanup. If you work outdoors, do field repairs, or want the simplicity of no gas, E71T-11 gets the job done.
Common Brands
- Lincoln Electric: Innershield NR-211-MP (the dominant E71T-11 product)
- Hobart: E71T-11 (retail packaging)
- Blue Demon: E71T-11
- Forney: E71T-11
Lincoln’s NR-211-MP is the industry reference. It’s available in 1 lb, 2 lb, 10 lb, and 25 lb spools at every welding supply store. Price at time of writing runs $6-8 per pound for small spools, dropping to $4-5 per pound for 10 lb and larger.
Storage
Store E71T-11 in its sealed packaging until use. Once opened, keep the spool in a dry area. The flux core can absorb moisture over time, leading to porosity. If a spool has been sitting open in a humid shop for months, test it on scrap before committing to a real weld. If you see excessive porosity, replace the spool.
Common Mistakes with E71T-11
Wrong polarity: DCEN for E71T-11. Running on DCEP (the standard MIG polarity) produces a violent, spattery arc with severe porosity. This is the most common setup error when switching from MIG to flux-core. Check polarity every time you change wire types.
Leaving gas on: The shielding gas solenoid should be closed when running self-shielded wire. External gas flow disrupts the flux-generated shielding chemistry and actually makes the weld worse, not better. Some welders assume gas plus self-shielding gives double protection. It doesn’t.
Short stickout: MIG wire runs at 3/8 to 1/2 inch stickout. E71T-11 needs 3/4 to 1 inch. The longer stickout preheats the flux core so it generates shielding gas effectively. Running at MIG stickout lengths produces inadequate shielding and porosity.
Pushing instead of dragging: Self-shielded flux-core must be run with a drag technique (pulling the gun). Pushing the gun rolls the slag ahead of the arc, which traps it in the weld and creates slag inclusions. Always drag.
Over-tightening drive rolls: The softer tubular wire crushes easily under excessive tension. Set tension to the minimum that feeds without slipping. If you see wire deformation or flattening at the drive rolls, back off the tension.
For a comparison with E71T-GS (the single-pass alternative), see the E71T-GS vs E71T-11 guide. For the gas-shielded option, see the E71T-1 gas-shielded flux-core guide. For the complete flux-cored wire overview, check the flux-cored wire selection guide.