Lincoln Fleetweld 35 is Lincoln Electric's E6011 stick welding rod — a high-cellulose potassium electrode that provides the deep penetrating arc of an E6010 with the bonus of reliable AC compatibility. Rated at 67,000 psi minimum tensile strength, the E6011 welding rod is the go-to choice for AC machine operators who need to weld through rust, mill scale, or moisture-contaminated base metal in maintenance, pipeline repair, construction, and general fabrication. Fleetweld 35 strikes easily, burns aggressively, and self-cleans weld-metal surfaces — qualities that make it indispensable on job sites where surface prep is limited.
Fleetweld 35 is Lincoln's standard E6011 cellulosic potassium SMAW electrode. The AWS designation E6011 decodes as: "E" = electrode; "60" = 62,000 psi typical / 67,000 psi minimum tensile; "1" = all-position; "1" = high-cellulose potassium flux enabling AC and DC operation. The distinction between E6011 and E6010 is the flux chemistry: E6010 uses sodium-based cellulosic flux and is DC-only; E6011 substitutes potassium for sodium, which stabilizes the arc on alternating current. Both produce the characteristic digging, fast-freeze arc that allows welding out-of-position on contaminated or wet base metal. Lincoln's Fleetweld 35 is the E6011 counterpart to the widely used Fleetweld 180 (E6010) and Pipeliner 6P+ (E6010) in Lincoln's lineup.
The cellulosic flux covering generates significant hydrogen during welding — E6011 is not low-hydrogen. This is inherent to the fast-freeze, penetrating arc mechanism. On most carbon steel base metals under 1 in thick without high restraint, hydrogen cracking risk is manageable. On high-carbon, high-alloy, or thick-restrained joints, preheat and a switch to low-hydrogen electrodes is required.
| Property | Specification |
|---|---|
| AWS Classification | E6011 |
| Tensile Strength (min.) | 67,000 psi (462 MPa) |
| Yield Strength (min.) | 55,000 psi (379 MPa) |
| Elongation (min.) | 22% |
| Flux Type | High-cellulose potassium |
| Current | AC, DCEP |
| Position | All (F, H, V-up, OH) |
| Available Diameters | 3/32, 1/8, 5/32, 3/16 in |
| Standard | AWS A5.1/A5.1M |
The 22 % elongation minimum of E6011 (vs. 17 % for E6013 and E7014) confirms higher weld metal ductility, making it suitable for dynamic-loaded structures where fillet welds may experience bending stresses. E6011 is NOT low-hydrogen — do not use on quenched-and-tempered steels or thick high-carbon joints without applying appropriate preheat.
- Field and maintenance welding on rusted, scaly, or coated base metal — the cellulosic arc burns through light rust, mill scale, and paint better than E7018 or E6013.
- Pipeline and cross-country pipe welding (AC machines) — where E6010 is preferred but only AC power is available, E6011 provides a nearly identical penetrating arc on AC.
- All-position structural fillet and groove welds — overhead, vertical-up, and out-of-position work on construction sites.
- Shipbuilding and repair — hull plates and structural members that may have moisture or coating contamination.
- Root pass welding on pipe and plate groove joints — in situations where E6010 is preferred but AC-only power is available.
- General structural welding per AWS D1.1 — E6011 appears in Table 4.5 as a prequalified filler metal for Group I and II base metals.
| Electrode Diameter | AC Amperage | DCEP Amperage |
|---|---|---|
| 3/32 in (2.4 mm) | 65–100 A | 60–90 A |
| 1/8 in (3.2 mm) | 90–140 A | 80–130 A |
| 5/32 in (4.0 mm) | 120–175 A | 110–165 A |
| 3/16 in (4.8 mm) | 155–225 A | 150–210 A |
Polarity: AC or DCEP (DC+). DCEP produces slightly better penetration and a quieter arc than AC. DCEN is generally not used with E6011 — the arc tends to be unstable and produces a rough bead.
Technique — Root passes: Use a tight arc length (1/2 to 1× core diameter). For root passes on pipe, use a keyhole technique: advance slowly enough to see a small keyhole ahead of the puddle, then fill it as you travel. A slight whipping motion (forward-hold-back) helps freeze the puddle between advances.
Vertical-up: Use the J-weave or whip technique; reduce amperage 10–15 A below midrange. E6011's fast-freeze slag supports the puddle in position better than E7014 or E6013.
Overhead: Keep the arc very short and amperage at the low end. The fast-freeze characteristic makes E6011 more manageable overhead than slow-freeze (titania) rods.
E6011 is a cellulosic electrode. Unlike low-hydrogen rods (E7018), cellulosic rods actually require some moisture in the flux to function correctly — the moisture combusts to produce a shielding hydrogen-CO2 gas envelope. Do NOT over-dry E6011:
- Storage temperature: 40–120 °F (4–49 °C) in a dry area. A standard sealed Lincoln container maintains the correct moisture level indefinitely under normal conditions.
- Do NOT bake at high heat: Never subject E6011 to the 250–300 °F drying cycles used for E7018. Over-drying a cellulosic electrode desiccates the flux and ruins arc performance — the electrode will produce a rough, sputtering arc and poor penetration.
- If wet: If electrodes have been heavily wetted (soaked or submerged), they should be discarded — restoring correct moisture balance is not practical in the field.
- Handle gently: Cellulosic flux coatings are more brittle than iron-powder coatings. Avoid dropping container or allowing electrodes to bend. Cracked or chipped flux degrades penetration and arc stability.
Fleetweld 35 is designed for mild and low-alloy carbon steel in the following grades:
- ASTM A36, A572 Grades 42 and 50
- API 5L Grade B, X42, X52 (with appropriate preheat for higher grades)
- ASTM A516 Grades 60 and 70 (pressure vessel plate)
- SAE 1018, 1020 carbon steel
E6011 is not recommended for stainless, cast iron, or high-alloy steels without consulting a filler metal specialist. Joint types: all groove and fillet geometries in all positions. Particularly well-suited for single-V and double-V groove joints where full penetration is required.
Preheat: For A36 up to 1 in thick at ambient above 32 °F, preheat is typically not required per AWS D1.1. For higher CE steels or thicker sections, consult the applicable code. Because E6011 produces high hydrogen, use conservative preheat when welding A572 Grade 65 or A588 above 3/4 in thick.
Q: What is the difference between E6011 and E6010?
E6010 uses a high-cellulose sodium flux and is DC-only (DCEP). E6011 uses a high-cellulose potassium flux that stabilizes the arc on AC current. Both produce similar deep-penetrating arcs and fast-freeze slag. If you have a DC-only inverter, use E6010. If you only have an AC buzz-box or need AC compatibility, E6011 is the correct choice.
Q: Can I use E6011 for pipe root passes?
Yes. E6011 is acceptable for root passes on pipe in applications where E6010 is normally preferred but only AC power is available. Use a tight arc length and keyhole technique for full-penetration root pass control. Consult the applicable welding procedure specification (WPS) — some pipe codes require E6010 specifically.
Q: Why should I NOT over-dry E6011?
Cellulosic electrodes like E6011 require residual moisture in the flux to generate the H2-CO2 shielding gas envelope that creates the penetrating arc and fast-freeze behavior. Over-drying at E7018 temperatures (250–300 °F) desiccates the flux, destroys arc performance, and makes the electrode functionally unusable.
Q: Is E6011 approved for AWS D1.1 structural welding?
Yes. E6011 is listed in AWS D1.1 Table 4.5 as an approved electrode for prequalified WPS on Group I and II base metals. It is not approved for Demand Critical applications or where CVN toughness classification is required.
Q: How does Fleetweld 35 compare to Fleetweld 180 E6010?
Both are cellulosic electrodes with similar deep-penetrating arc characteristics. Fleetweld 180 (E6010) is DCEP-only and produces a slightly crisper arc with less spatter on DC power. Fleetweld 35 (E6011) adds AC compatibility at a small cost to arc crispness. If you only have DC, use E6010; for AC machines, Fleetweld 35 is the equivalent alternative.
Q: What polarity runs best for E6011 — AC or DCEP?
DCEP (DC+) gives a slightly smoother, more penetrating arc than AC. AC is acceptable and widely used in field environments. DCEN (DC-) is not recommended for E6011 — the arc tends to be unstable.
Q: What is the maximum plate thickness for E6011 without preheat?
For ASTM A36 welded per AWS D1.1, no preheat is required for material up to 1 in thick when ambient temperature is above 32 °F. For higher-alloy or thicker sections, consult the code for minimum preheat requirements.
The E6011 stick welding rod is the AC-capable equivalent of the E6010, sharing the deep-penetrating cellulosic arc mechanism with the added benefit of AC arc stability through potassium flux stabilizers. When choosing an E6011 welding rod for maintenance, pipeline, or field fabrication work, the critical selection criteria are: (1) AC machine compatibility — all E6011 rods run on AC but flux quality varies; lower-quality E6011 formulations can still be erratic on older buzz-boxes; Lincoln Fleetweld 35 uses a premium potassium-enhanced covering optimized for 60 Hz AC; (2) Flux coating integrity — the cellulosic coating should have no cracks or chips; (3) Storage condition — never oven-dried; stored sealed in a cool, dry location. E6011 is frequently specified in AWS D1.1 prequalified WPS for group I and II base metals in field and maintenance welding applications where rust, scale, and moisture contamination are present. It is also used in pressure vessel fabrication (ASME Section VIII) for root passes on carbon steel where the full-penetration root must be made without ceramic backing. The 22% elongation of E6011 weld metal is among the highest for any carbon-steel electrode, contributing to the crack-resistant weld deposits needed for dynamically loaded structures in field conditions.