Every stick electrode box you pick up at the welding supply store has a code printed on it. E6010. E7018. E6013. If you have been welding for a while, you probably recognize a few of these numbers and know roughly which rod to grab for a given job. But what do those digits actually mean?
The AWS classification system is a standardized code that tells you everything you need to know about a stick electrode: its strength, the positions it can weld, what kind of coating it has, and what electrical settings it needs. Once you learn to read the code, you can evaluate any electrode you encounter, not just the half-dozen common ones. This guide breaks down the AWS classification system digit by digit, explains the major coating types and their real-world behavior, provides amperage starting points for common electrode sizes, and covers proper storage and handling, with particular attention to low-hydrogen electrodes.
Whether you are setting up for a structural job, repairing equipment in your shop, or just trying to understand what is in that dusty box in the corner, knowing the classification code puts you in control of your rod selection.
AWS Electrode Classification Code Explained
The AWS classification for carbon steel stick electrodes follows a consistent pattern: the letter E followed by four or five digits. Each part of the code carries specific information about the electrode’s properties and intended use. Per AWS A5.1, the specification that governs carbon steel electrodes for shielded metal arc welding, every digit in the code has a defined meaning.
The “E” Prefix
The letter E identifies the product as an electrode for arc welding. Every AWS classification for a stick electrode starts with E. There are no exceptions for carbon steel electrodes. When you see the E on a box, you know the product inside is designed to carry welding current and serve as filler metal.
Tensile Strength Digits
The first two digits after the E indicate the minimum tensile strength of the weld metal in thousands of pounds per square inch (ksi). An E6010 electrode, for example, has a minimum tensile strength of 60,000 psi after welding. An E7018 electrode has a minimum tensile strength of 70,000 psi.
The most common tensile strength values you will encounter are 60 (60,000 psi, approximately 413 MPa) and 70 (70,000 psi, approximately 482 MPa). Higher-strength electrodes exist for specialized applications, but for the home shop and general fabrication work, E60XX and E70XX cover the vast majority of jobs.
Position Digit
The third digit (or the fourth digit in some 5-digit codes) tells you which welding positions the electrode is capable of running.
A position code of 1 means the electrode can be used in all positions: flat, horizontal, vertical (uphill and downhill depending on the electrode), and overhead. This is the most versatile position rating and is common on electrodes like E6010, E6011, E6013, and E7018.
A position code of 2 means the electrode is limited to flat and horizontal positions only. E7024 carries a position 2 rating because its heavy iron-powder coating and high deposition rate make it impractical to weld out of position.
A position code of 3 means flat only. This is an older classification that is rarely encountered in modern electrodes.
Position 1 electrodes give you more flexibility but may require more skill to run out of position. Position 2 electrodes are easier to use in flat and horizontal work and offer higher deposition rates for production welding.
Coating and Current Digit
The last digit (or last two digits) of the classification is the most information-rich part of the code. It tells you the coating type and the compatible current and polarity. This is where the real differences between electrodes become clear.
Each suffix digit corresponds to a specific coating formulation and a defined set of electrical requirements. Here is the full mapping of the common suffix codes:
- 0: Cellulose sodium coating, DC+ (electrode positive) only
- 1: Cellulose potassium coating, AC or DC+
- 2: Rutile sodium coating, DC- (electrode negative) or AC
- 3: Rutile potassium coating, AC or DC+
- 4: Iron powder rutile coating, AC or DC+
- 5: Low-hydrogen sodium coating, DC+ only
- 6: Low-hydrogen potassium coating, AC or DC+
- 8: Low-hydrogen iron powder coating, AC or DC+
The coating type determines the arc characteristics, slag system, penetration profile, and whether the electrode requires special storage. The current/polarity designation tells you whether your welding machine must be set to DC positive, DC negative, or if AC is acceptable.
Classification Code Decoder Table
The table below summarizes how to read any AWS carbon steel electrode classification.
| Digit Position | Meaning | Example (E6010) | Other Common Values |
|---|---|---|---|
| E | Electrode | E = electrode | All classifications start with E |
| 60 | Tensile strength in ksi | 60 = 60,000 psi (413 MPa) | 70 = 70,000 psi (482 MPa) |
| 1 | Position capability | 1 = all positions | 2 = flat/horizontal only; 3 = flat only |
| 0 | Coating type and current/polarity | 0 = cellulose sodium, DC+ only | 1 = cellulose potassium, AC or DC+; 2 = rutile sodium, DC- or AC; 3 = rutile potassium, AC or DC+; 4 = iron powder rutile, AC or DC+; 5 = low-hydrogen sodium, DC+; 6 = low-hydrogen potassium, AC or DC+; 8 = low-hydrogen iron powder, AC or DC+ |
Try reading a few codes yourself. An E7018 breaks down as: E (electrode), 70 (70,000 psi tensile strength), 1 (all positions), 8 (low-hydrogen iron powder coating, AC or DC+). An E6011 is: E (electrode), 60 (60,000 psi), 1 (all positions), 1 (cellulose potassium coating, AC or DC+).
Coating Types and Their Meaning
The coating on a stick electrode is not there for decoration. It performs several critical jobs: it creates a shielding gas to protect the molten weld pool from the atmosphere, it adds deoxidizers and alloying elements to the weld metal, it controls the shape of the arc and the depth of penetration, and it forms a slag blanket that protects the cooling weld bead. Each coating type produces different welding characteristics.
Cellulose Coatings (EXX10, EXX11)
Cellulose-based coatings contain organic compounds that decompose in the arc to produce a substantial volume of shielding gas. This gas shield protects the weld pool while the coating also creates a fast-freeze slag that solidifies quickly, allowing the electrode to weld in all positions without the puddle running out.
Cellulose electrodes are known for their deep-penetrating, digging arc. E6010 is widely considered the standard for pipe root passes because its deep penetration ensures full fusion into the root face. The fast-freeze slag also produces the characteristic stack-of-dimes bead appearance that pipe welders aim for.
The difference between E6010 and E6011 comes down to the specific formulation of the coating. E6010 uses cellulose sodium and requires DC+ (reverse polarity) per AWS A5.1 classification. E6011 uses cellulose potassium, which allows it to run on AC or DC+. If you have an AC-only machine or need to mitigate arc blow in a magnetic joint, E6011 gives you the same digging arc with AC capability. For a detailed breakdown of the differences between these two electrodes, see our 6010 vs 6011 comparison.
Rutile Coatings (EXX12, EXX13)
Rutile coatings are based on titanium dioxide (rutile) and produce a smooth, stable arc with low spatter and easily removable slag. These electrodes are often described as user-friendly because they are forgiving of less-than-perfect technique.
E6013 is the most common rutile electrode. It produces a light-to-medium penetrating arc with a soft, quiet burn. The slag lifts off easily, often by itself as the weld cools. These characteristics make E6013 a popular choice for sheet metal, light fabrication, and welding thin-gauge materials where excessive penetration would cause burn-through.
E6012 (rutile sodium) is less common but notable because it runs on DC- (straight polarity) or AC. Its coating is designed to handle poor fit-up conditions, bridging gaps that other electrodes would struggle with.
Rutile electrodes are not the best choice for deep-penetration root passes or high-strength structural work, but for general fabrication on clean, well-fitted material, they are hard to beat.
Low-Hydrogen Coatings (EXX15, EXX16, EXX18)
Low-hydrogen electrodes use a mineral-based coating with very low moisture content. The purpose is to minimize the amount of hydrogen that can enter the weld metal during solidification. Hydrogen is a problem because it can cause hydrogen-induced cracking (also called cold cracking or delayed cracking) in the weld and heat-affected zone, particularly in higher-strength steels and restrained joints.
E7018 is the most widely used low-hydrogen electrode. It contains iron powder in the coating, which increases deposition rate and produces a smooth, stable arc with good wetting action. The slag is easy to remove, and the bead appearance is clean and flat. E7018 is commonly used for structural steel and code work where low-hydrogen electrodes are required. AWS D1.1 recognizes E7018 as a code-compliant electrode for structural welding.
E7015 and E7016 are also low-hydrogen classifications, though less common. E7015 is DC+ only; E7016 can run on AC or DC+. Both are used in structural and heavy-equipment welding where low-hydrogen properties are required.
Low-hydrogen electrodes require proper storage to maintain their low-moisture coating. This is covered in detail in the Electrode Storage and Handling section below.
Iron Powder Coatings (EXX14, EXX24)
Iron powder in the electrode coating serves a straightforward purpose: it adds filler metal to the weld. When the coating burns in the arc, the iron powder melts and becomes part of the weld deposit, increasing the deposition rate without requiring the welder to move faster.
E7014 combines iron powder with a rutile base. It produces a smooth arc with medium penetration and is known for handling poor fit-up well. The slag is heavy but comes off easily.
E7024 contains a high percentage of iron powder in a titania-based coating. It carries a position 2 classification, meaning it is suitable for flat and horizontal welding positions only. The deposition rate is significantly higher than E7018, making E7024 a production electrode for large fillet welds on flat plate. The slag is thick and easy to remove, and the bead comes out smooth and flat.
These iron-powder electrodes are not ideal for vertical or overhead work, but for flat and horizontal production welding, they save time and increase productivity.
Current and Polarity Requirements
Different electrodes require different current and polarity setups. Understanding why is a matter of knowing what the coating needs to function correctly. The coating chemistry determines the ionization characteristics of the arc, which in turn determines whether the electrode prefers DC positive, DC negative, or AC.
DC Electrode Positive (DCEP / Reverse Polarity)
DC electrode positive, also called reverse polarity, means the electrode holder is connected to the positive terminal of the welding machine and the work clamp is connected to the negative terminal. This is the most common polarity for stick welding.
DCEP is commonly required or recommended for many SMAW electrodes and is often associated with deeper penetration depending on electrode classification and coating design. The electrode classification and manufacturer data sheet determine the required polarity. It also provides better cleaning action, removing oxides and contaminants from the base metal surface. Electrodes that require DCEP include E6010, E6011 (also AC), E6013 (also AC), E7015, and E7018 (also AC).
DC Electrode Negative (DCEN / Straight Polarity)
DC electrode negative, or straight polarity, is the reverse of DCEP. The electrode holder is connected to the negative terminal and the work clamp to the positive terminal. DCEN is commonly associated with lower penetration for the SMAW classifications that permit it, but the usable effect depends on electrode classification, coating design, arc length, amperage, joint geometry, and manufacturer data. Follow the electrode classification and product data sheet.
DCEN is used with E6012, which is the only common carbon steel stick electrode classified for DCEN operation. Some welders also use DCEN for specific applications like welding thin materials where less penetration is desired, but this is technique-dependent and not standard per classification.
AC Capability
Many electrodes are designed to run on alternating current. AC capability is valuable for two main reasons. First, it allows welding with AC-only machines like transformer buzz boxes. Second, AC welding eliminates arc blow, a magnetic phenomenon that deflects the arc in DC welding, particularly when welding near magnets, in corners, or on materials with residual magnetism.
Electrodes classified for AC operation include E6011, E6012, E6013, E7014, E7016, E7018, and E7024. Note that while E7018 is classified for AC or DC+, not all E7018 products perform equally on AC. Some manufacturers offer specific AC-rated variants of E7018 formulated for better AC arc stability.
E6010 and E7015 are classified as DC+ only per AWS A5.1. Some manufacturer variants of these classifications may offer AC capability, but the standard classification requires DC+.
A quick-reference guide to electrode polarity:
| Electrode | DC+ (DCEP) | DC- (DCEN) | AC |
|---|---|---|---|
| E6010 | Required | No | No (standard classification) |
| E6011 | Yes | No | Yes |
| E6012 | No | Yes | Yes |
| E6013 | Yes | No | Yes |
| E7014 | Yes | No | Yes |
| E7015 | Required | No | No |
| E7016 | Yes | No | Yes |
| E7018 | Yes | No | Yes (including AC variants) |
| E7024 | Yes | No | Yes |
Amperage Starting Points
Amperage selection is one of the most common questions new welders ask, and with good reason. Too low and the electrode stubs out and sticks. Too high and you burn through the base metal or lose control of the puddle. The right amperage depends on the electrode classification, its diameter, the welding position, the material thickness, and the specific product you are using.
How Electrode Diameter Affects Amperage
Larger diameter electrodes require higher amperage to melt the core wire and maintain proper arc characteristics. A 1/8-inch (3.2 mm) electrode needs roughly twice the amperage of a 3/32-inch (2.4 mm) electrode of the same classification. The relationship is not perfectly linear, but the trend holds across all electrode types.
Common electrode diameters you will encounter include 3/32 inch (2.4 mm), 1/8 inch (3.2 mm), and 5/32 inch (4.0 mm). Smaller diameters like 1/16 inch (1.6 mm) and 5/64 inch (2.0 mm) exist for thin gauge work and specialty applications. Larger diameters like 3/16 inch (4.8 mm) and 1/4 inch (6.4 mm) are used for high-deposition welding on heavy plate.
How Position Affects Amperage
The welding position has a significant effect on the usable amperage range. In the flat position, gravity works with you, and you can run at the middle to upper end of the electrode’s amperage range. In vertical and overhead positions, gravity works against you, and you need to reduce amperage to keep the puddle under control.
As a general starting point, reduce amperage by 10 to 20 percent from your flat-position setting when welding vertical or overhead. Start at the lower end of the range and increase until you have good puddle control without the metal sagging or running.
Starting-Point Amperage Reference Table
The following table provides composite starting amperage ranges compiled from manufacturer data sheets (Lincoln Electric, ESAB, Hobart, and Miller). These are starting points only. Actual amperage varies by product brand, material thickness, joint configuration, welding position, and individual technique. Always consult the manufacturer data sheet for the specific electrode product you are using. For code work, the Welding Procedure Specification (WPS) governs the required amperage.
| Electrode | 3/32″ (2.4 mm) | 1/8″ (3.2 mm) | 5/32″ (4.0 mm) |
|---|---|---|---|
| E6010 | 40-80 A | 75-130 A | 110-165 A |
| E6011 | 40-80 A | 75-130 A | 110-165 A |
| E6012 | 35-75 A | 70-125 A | 110-160 A |
| E6013 | 35-75 A | 70-130 A | 110-165 A |
| E7014 | 35-80 A | 80-140 A | 120-180 A |
| E7018 | 50-90 A | 90-160 A | 130-220 A |
| E7024 | Not typical for this size | 110-180 A | 150-230 A |
These ranges represent typical starting points. Start at the lower end of the range for out-of-position welding and for thinner materials. Move toward the middle or upper end for flat-position welding on thicker plate. If the electrode sticks or the arc is unstable, increase amperage. If the weld puddle feels too fluid or you are getting burn-through, decrease amperage.
Electrode Storage and Handling
Proper electrode storage is important for weld quality and safety. The requirements vary significantly by electrode type, with low-hydrogen electrodes demanding the most attention.
Low-Hydrogen Electrode Storage Requirements
Low-hydrogen electrodes (EXX15, EXX16, EXX18) are manufactured with a coating that has very low moisture content. This low moisture level is what gives them their hydrogen-reducing properties. If the coating absorbs moisture from the air, the electrode no longer meets its low-hydrogen classification, and the risk of hydrogen-induced cracking increases.
Per AWS D1.1, the structural welding code, low-hydrogen electrodes must be stored in hermetically sealed containers or in a ventilated holding oven at manufacturer-recommended temperatures. When stored in a sealed container that has never been opened, the electrodes are considered dry and ready to use.
Once a sealed container is opened, the electrodes begin absorbing moisture from the air. AWS D1.1 specifies a limited exposure time for low-hydrogen electrodes after opening. The typical allowable exposure time for E7018 is up to four hours, but the applicable code edition and the manufacturer’s specific recommendations should always be checked. Different codes and different products may have different limits.
For electrodes that need to be kept dry during a work shift, a portable holding oven is the standard solution. Manufacturer recommendations typically specify a holding temperature of 120 to 150 degrees Celsius (250 to 300 degrees Fahrenheit) for low-hydrogen electrodes stored in a ventilated oven.
Electrodes that exceed their allowable atmospheric exposure time can be rebaked to restore their low-moisture condition. A typical rebaking schedule, per manufacturer recommendations such as Lincoln’s Excalibur guide, is 260 to 315 degrees Celsius (500 to 600 degrees Fahrenheit) for one hour. The specific rebaking temperature and time depend on the electrode product and the governing code. Always follow the manufacturer’s data sheet and the applicable code edition for rebaking requirements.
Electrodes with cracked, chipped, or wet coating must be discarded. Low-hydrogen electrodes that have been submerged in water or exposed to high humidity for extended periods are not safe to use. Our Common Stick Welding Defects guide covers hydrogen-induced cracking and other electrode-related defects in more detail.
Storage for Non-Low-Hydrogen Electrodes
Cellulose electrodes (E6010, E6011) and rutile electrodes (E6012, E6013) are not moisture-sensitive in the same way as low-hydrogen types. They do not require oven storage or hermetically sealed containers to maintain their classification properties.
That said, they should still be stored in dry conditions. Keep them in their original sealed packaging or in a clean, dry container. Avoid storing electrodes in damp basements, uninsulated sheds, or areas subject to condensation. A simple plastic storage box with a desiccant pack is adequate for most home shop conditions.
One important point: do not oven-dry cellulose electrodes at low-hydrogen temperatures. The high heat can damage the cellulose coating and degrade electrode performance. Some manufacturers recommend a low-temperature drying cycle (50 to 80 degrees Celsius, or 120 to 175 degrees Fahrenheit) if electrodes have been exposed to high humidity, but the manufacturer’s specific guidance should be followed. Interestingly, E6010 and E6011 actually depend on a small amount of moisture in the coating to generate the gas shield that protects the weld pool. Overdrying can reduce their performance.
Identifying and Discarding Damaged Electrodes
Regardless of type, any electrode with visible damage should be discarded. Signs of damage include cracked coating, rust on the exposed core wire, coating that flakes or chips off easily, and moisture beads or wet spots on the coating surface.
Electrodes that have been submerged in water, stored in a flooded area, or subjected to high humidity for extended periods should not be used, regardless of classification. The coating integrity and welding characteristics are compromised, and the risk of weld defects increases significantly.
Common Electrode Reference Table
The following table brings together the key information for each common AWS electrode classification. Use this as a quick reference when selecting an electrode for a specific job. For amperage ranges, refer to the amperage starting points table in the previous section.
| AWS Class | Coating Type | Current/Polarity | Positions | Penetration | Characteristics | Common Applications |
|---|---|---|---|---|---|---|
| E6010 | Cellulose sodium | DC+ | All | Deep | Digging arc, fast-freeze, DC only | Pipe root passes, structural repair, galvanized steel |
| E6011 | Cellulose potassium | AC or DC+ | All | Deep | Similar to 6010 but AC-capable, versatile | Pipe, structural, farm and field repair where only AC is available |
| E6012 | Rutile sodium | DC- or AC | All | Medium | Good gap bridging, moderate penetration | Poor fit-up joints, general fabrication, horizontal fillets |
| E6013 | Rutile potassium | AC or DC+ | All | Light to medium | Smooth arc, low spatter, easy slag removal | Sheet metal, light fabrication, thin-gauge welding |
| E7014 | Iron powder rutile | AC or DC+ | All | Medium | High deposition, smooth arc, good for poor fit-up | General fabrication, production welding, fillet welds |
| E7015 | Low-hydrogen sodium | DC+ | All | Medium to deep | Low-hydrogen, DC only, good mechanical properties | Structural steel, heavy equipment in DC-only shops |
| E7016 | Low-hydrogen potassium | AC or DC+ | All | Medium to deep | Low-hydrogen, AC capable, good impact properties | Structural steel, code work requiring low-hydrogen with AC |
| E7018 | Low-hydrogen iron powder | AC or DC+ | All | Medium | Low-hydrogen, excellent mechanical properties, smooth bead | Structural steel per AWS D1.1, heavy fabrication, code-critical welds |
| E7024 | Iron powder titania | AC or DC+ | Flat and horizontal | Medium | Very high deposition, iron powder in coating, heavy slag | Production welding, large fillet welds, flat and horizontal positions |
For guidance on technique and setup, see our stick welding techniques for beginners guide. For in-depth comparison of specific electrode pairs, see our Stick Welding Defects guide covering hydrogen-induced cracking and other electrode-related defects, and our 6010 vs 7018 comparison guide, our 6010 vs 6011 comparison, and our 6013 vs 7018 comparison article. For single-electrode deep dives, our 6013 Welding Rod Uses guide and 7018 Welding Rod Uses article provide focused coverage.
When to Choose Which Electrode
Matching the electrode to the job is a matter of understanding what each classification is designed to do. Here is practical guidance for common welding scenarios.
General-Purpose and Structural Welding (E7018)
E7018 is commonly used in structural and code-regulated steel work where low-hydrogen electrodes are required or specified. The governing welding procedure specification (WPS), applicable code edition, engineer of record, and electrode manufacturer data sheet control the actual electrode choice.
Beyond code work, E7018 produces a smooth bead with good wetting and easy slag removal, which makes it popular for visible welds and general heavy fabrication. The trade-off is that it requires proper storage and handling to maintain its low-hydrogen properties. If you are welding structural steel, heavy equipment, or anything where a weld failure would be costly or dangerous, E7018 is the right starting point.
Pipe and Root Pass Welding (E6010, E6011)
The deep-penetrating digging arc of cellulose electrodes is what makes E6010 and E6011 the standard choice for pipe root passes. The arc penetrates into the root face and ensures full fusion, while the fast-freeze slag holds the puddle in place during vertical and overhead welding.
E6010 is the traditional choice when DC is available. E6011 offers the same deep-penetration characteristics with AC capability, which is useful for arc blow mitigation or when only an AC machine is available. For a detailed comparison of these two electrodes, see our 6010 vs 6011 guide.
Sheet Metal and Light Fabrication (E6013)
When you are welding thin-gauge material where burn-through is a concern, E6013 is a strong choice. Its smooth, stable arc and light-to-medium penetration reduce the risk of blowing through thin metal. The slag lifts off easily, often without needing a chipping hammer.
E6013 is also widely recommended for beginners because the forgiving arc makes it easier to learn consistent bead technique. That said, beginners can certainly learn on other electrodes with practice. For more on E6013 applications, see our 6013 Welding Rod Uses guide.
High-Deposition and Production Welding (E7024, E7014)
When the job calls for filling a large fillet weld or running long, continuous beads on flat plate, iron-powder electrodes offer significant productivity gains. E7024 can deposit more filler metal per hour than E7018, thanks to the iron powder in the coating that becomes part of the weld deposit.
The trade-off is position limitation. E7024 carries a position 2 classification, meaning it is suitable for flat and horizontal welding positions only. It is not designed for vertical or overhead use. E7014 offers similar benefits in all positions with a slightly lower deposition rate. These electrodes are most at home in production environments where maximizing deposition rate in flat and horizontal work is the priority.
Safety Notes
Stick welding involves electrical current, high temperatures, ultraviolet radiation, and fume exposure. The following safety notes focus on hazards directly related to electrode selection, handling, and use.
Arc flash protection is non-negotiable. The welding arc produces intense ultraviolet radiation that can cause a painful condition known as welder’s flash (photokeratitis) in a matter of seconds. Always wear a welding helmet with the proper shade filter, compliant with ANSI Z87.1. Cover all exposed skin to prevent UV burns. Leather welding gloves, a flame-resistant long-sleeve shirt or jacket, and leather boots are the minimum acceptable PPE. Avoid synthetic fabrics near the welding arc, as they can melt and cause severe burns.
Fume exposure is a serious concern. Stick welding produces fume containing manganese, iron oxide, and other compounds that can be harmful when inhaled. Weld in a well-ventilated area. For indoor welding, use local exhaust ventilation to remove fume at the source. Our Welding Fume Extraction and Respirator Selection guide covers fume management in detail.
Low-hydrogen electrode handling requires attention when electrodes have been in a holding oven. Dried electrodes reach oven temperature and can cause burns if handled without proper gloves or tongs. Always use heat-rated gloves or tongs when handling electrodes from a rod oven.
Fire prevention is essential whenever welding. Hot slag, spatter, and electrode stubs are ignition sources that can start fires well after the welding arc is extinguished. Per OSHA 1910.252(a), maintain a 35-foot clearance from combustibles when welding. Keep a fire extinguisher in the work area. Dispose of hot electrode stubs in a dedicated metal container, not in a trash can. Allow stubs to cool completely before final disposal. Our Welding Shop Fire Prevention guide covers comprehensive fire safety for the welding shop.
Electrode disposal: hot stubs can cause burns and start fires. Keep a metal stub bucket in your welding area and use it consistently. Never leave hot stubs on the floor, workbench, or in plastic containers.
