Stick Welding (SMAW) Fundamentals

Shielded Metal Arc Welding (SMAW), commonly called "stick welding," is the oldest and most versatile arc welding process in the trades. A coated electrode (the "rod") carries current from the welding machine to the workpiece. The heat of the arc melts both the rod and the base metal, and the flux coating on the rod burns off to form a shielding gas and a protective slag blanket over the weld. Stick welding does not require external shielding gas, which is why it remains the first choice for ironworkers, pipeline crews, farmers, and maintenance welders working outdoors, in the wind, or on dirty, rusted material where MIG and TIG will not perform. This guide covers everything you need to strike your first arc with confidence and avoid the mistakes that slow down new welders.

Safety First - The Non-Negotiables

Stick welding exposes you to all of the same hazards as any arc process, plus a few that are specific to SMAW. Read this section before you plug the machine in.

Arc Flash and UV Radiation

The SMAW arc burns at around 10,000 degrees F and produces intense ultraviolet and infrared radiation. A single unprotected glance at an arc will give you arc eye (photokeratitis) - a painful sunburn on the surface of your eyes that feels like sand under your eyelids about 6 to 12 hours after exposure. Always wear a welding helmet with the correct shade before striking an arc:

• Shade 10 - Up to 80 amps
• Shade 11 - 80 to 160 amps
• Shade 12 - 160 to 250 amps
• Shade 13 - 250 to 500 amps

Auto-darkening helmets are standard in modern shops. Test the sensors by pointing the lens at a bright light or striking a practice arc with the hood cocked up - it should snap to dark instantly.

Fume Exposure

SMAW generates more fume per minute of arc-on time than MIG or TIG. Low-hydrogen rods (E7018 and similar) throw heavier fume clouds than E6013. Welding galvanized steel, stainless, or painted metal multiplies the hazard. Use local exhaust ventilation whenever possible, keep your head out of the plume, and wear a P100 respirator or PAPR when cutting out galvanized or coated material. Never run stick welds in a confined space without forced ventilation and gas monitoring.

Electric Shock

SMAW machines run at 50 to 100 open-circuit volts - enough to kill if you provide a path to ground while your skin is wet or sweaty. Keep your gloves dry. Never change rods with bare hands. Never touch the electrode holder and the work clamp at the same time. Do not weld while standing in water or leaning against a wet grounded surface.

Understanding SMAW Current and Polarity

Stick welders output either DC (direct current) or AC (alternating current). Polarity is one of the three dials you set before every weld, and getting it wrong is the single most common beginner mistake.

• DCEP (DC Electrode Positive, also called "reverse polarity") - The electrode is positive, the work is negative. About two-thirds of the heat goes into the electrode and one-third into the work. DCEP gives the deepest penetration and is the most common polarity for structural work. Most general-purpose rods (E6010, E6011, E7018) are designed to run DCEP.
• DCEN (DC Electrode Negative, also called "straight polarity") - The electrode is negative, the work is positive. Heat distribution reverses - more heat into the base metal, less into the rod. Gives a faster melt-off rate but shallower penetration. Used with some rods (like E6013 on sheet metal) to prevent burn-through.
• AC (Alternating Current) - Current reverses 60 times per second. The arc is noisier and slightly less smooth than DC, but AC eliminates "arc blow" on magnetized parts. Old buzz-box transformer machines run AC only. Rods like E6011 and E7018-AC are designed to run on AC.

When in doubt, check the rod manufacturer's label. Every stick electrode has a recommended polarity printed on the box.

Electrode Classification - Reading the Numbers

AWS classifies carbon-steel electrodes with a five-digit code like E7018:

• E = Electrode
• First two (or three) digits (70) = Minimum tensile strength of the deposited weld in ksi. E6010 = 60,000 psi. E7018 = 70,000 psi.
• Third digit (1) = Welding position. 1 = all positions, 2 = flat and horizontal fillets only.
• Fourth digit (8) = Flux type and current. See the table below.

| Rod    | Polarity    | Penetration   | Best For                                  |
|--------|-------------|---------------|-------------------------------------------|
| E6010  | DCEP        | Deep/digging  | Root passes on pipe, rusty/dirty steel    |
| E6011  | AC or DCEP  | Deep/digging  | Same as 6010 but runs on AC (buzz-box)    |
| E6013  | AC/DCEP/DCEN| Shallow/soft  | Sheet metal, light fab, easy starts       |
| E7014  | AC/DCEP/DCEN| Medium        | Fast fill, iron-powder rod, forgiving     |
| E7018  | AC or DCEP  | Medium        | Structural, code work, low-hydrogen       |

E6010 runs a fast-freezing, digging arc that punches through rust, paint, and mill scale. Pipeline welders use 6010 for downhill root passes.

E7018 is the workhorse of structural welding. The "low-hydrogen" flux coating reduces hydrogen-induced cracking in critical welds. 7018 rods must be kept dry - once a can is opened, rods live in a heated rod oven at 250 to 300 degrees F. A wet 7018 will porosity-pop all over your weld.

E6013 is the easy-start, beginner-friendly rod. Forgiving arc, mild penetration, clean slag release. Great for sheet metal and farm repair, not acceptable for code structural work.

Setting Up the Machine

1. Clean the work and attach the ground clamp - Slag, rust, and paint under the work clamp cause erratic arcs. Clamp to bare metal as close to the weld as practical.
2. Select polarity - Match it to the rod. DCEP for 7018, 6010, 6011 on DC. DCEN only if the rod specifically calls for it.
3. Set amperage - Rule of thumb: 1 amp per 0.001 inch of rod diameter, adjusted for position. For a 3/32 inch 7018 in flat position, start around 90 to 95 amps. For 1/8 inch 7018, start around 115 to 130 amps. Drop 10 to 15 percent for vertical or overhead.
4. Inspect the rod - No cracks in the flux, no moisture stains, no rust on the bare tail.
5. Insert the rod into the stinger - Clamp on the bare tail end, flux end pointing out.

Rod Angle - Work and Travel

Two angles matter. Learn to set both before every bead.

• Work angle - The angle of the rod relative to the two joint surfaces, viewed from the end of the joint. On a flat groove weld, the work angle is 90 degrees (rod vertical). On a T-joint fillet, the work angle is 45 degrees - the rod points into the corner so heat and filler distribute evenly to both plates.
• Travel angle - The angle of the rod relative to the direction of travel, viewed from the side. For SMAW you almost always use a drag (or backhand) angle: tilt the rod 10 to 15 degrees away from the direction of travel, so the arc pulls the slag behind the puddle. If you push SMAW (forehand), slag rides in front of the arc, gets trapped under the bead, and creates slag inclusions.

Remember: "drag stick, push wire." Stick welding drags. MIG pushes (or drags, depending on preference). Know the difference.

Stringer Beads vs. Weave Beads

• Stringer bead - Rod moves in a straight line down the joint, no side-to-side motion. Narrow, controlled bead. Preferred for root passes, high-strength code welds, and most 7018 work. Multiple stringer passes can be stacked to fill a groove.
• Weave bead - Rod oscillates side to side while advancing. Produces a wider bead that fills thicker joints faster. Common weave patterns: crescent (C-shape), zigzag, figure-8, box. Pause briefly at the outside edge of each weave to fuse the toe and prevent undercut.

AWS D1.1 limits weave width to around 2.5 times the rod core wire diameter for most structural joints. Wider weaves trap slag and lose arc energy over the joint bevel.

Travel Speed and Arc Length

Two symptoms tell you your travel speed is wrong:

• Bead too tall and narrow = Travel too slow (overbuilt)
• Bead too flat and wide with spatter = Travel too fast (underfilled)

A properly paced SMAW bead is about 2 to 3 times the rod diameter wide and slightly crowned.

Arc length for most rods should be approximately equal to the rod's core wire diameter - roughly 1/8 inch arc for a 1/8 inch rod. E6010 is the exception: it runs best with a "whip and pause" technique where the arc is stretched out briefly then returned to the puddle. Too long an arc causes porosity, spatter, and undercut. Too short an arc causes sticking and freezing.

Slag Removal and Inter-Pass Cleaning

After every pass, stop, cool, and clean before laying the next bead:

1. Wait until the slag cools from bright orange to dark gray (about 5 to 10 seconds).
2. Tap the slag off with a chipping hammer, working from one end of the bead to the other.
3. Wire-brush the weld and the heat-affected zone. A power wire wheel on an angle grinder is faster for production work.
4. Inspect for any surface defects - porosity, undercut, lack of fusion at the toe. Grind out defects before covering them with the next pass.
5. If the previous pass has a high crown or a ropy surface, grind it lightly flat. Slag hides under overhangs and causes inclusions.

Wear safety glasses under your helmet. Chipping hammer shards bounce hard and will find your eye through a cracked face shield.

Troubleshooting Common SMAW Defects

| Symptom             | Likely Cause                          | Fix                                  |
|---------------------|---------------------------------------|--------------------------------------|
| Porosity            | Wet rod, dirty base metal, long arc   | Dry rod, clean metal, shorten arc    |
| Undercut            | Amps too hot, travel too fast, wrong angle | Drop amps, slow down, adjust angle |
| Sticking/freezing   | Amps too low, arc too short           | Increase amps, lift slightly         |
| Sticky starts       | Cold rod, dirty work clamp, wrong polarity | Restrike, clean clamp, check polarity |
| Slag inclusions     | Push travel, weave too wide, dirty inter-pass | Drag, tighten weave, wire brush   |
| Arc blow            | Magnetic field on DC                  | Reposition ground, switch to AC      |
| Fish-eye porosity   | Hydrogen in weld metal (wet 7018)     | Rebake rods at 500-700 F for 1 hour  |

Vertical Up vs. Vertical Down

• Vertical up (3G up) - Slower, deeper penetration, stronger. Required for code structural work. Use stringer or a slight triangle/upside-down-T weave. Amps 10 to 15 percent lower than flat.
• Vertical down (3G down) - Faster, shallower penetration. Used on thin sheet and pipeline root passes with E6010. Run with a fast, tight stringer. Gravity pulls the puddle down, so keep the arc ahead of the slag.

If the spec does not say vertical down explicitly, weld vertical up.

Day 1 Checklist

• Helmet tested, correct shade, clean lens cover
• Leather jacket/sleeves, gauntlet gloves, closed-top boots, no synthetics
• Fire extinguisher within 10 feet, flammables cleared 35 feet
• Fume extractor positioned, natural ventilation adequate
• Machine set: polarity checked, amps set, cables inspected
• Rod selection matches job and polarity; 7018 rods from a hot oven
• Work clamp on clean bare metal, as close to the weld as possible
• Scrap coupon of the same material and thickness, ready for a test bead

Expert Tips

• "Watch the puddle, not the arc." The back edge of the puddle tells you everything about travel speed and heat.
• "Drag it like a pencil." If you push stick, slag rolls in front of the arc and gets buried.
• "Cold rods make cold welds." Keep 7018 in an oven. Period.
• "Grind it or regret it." Any defect left uncovered becomes a defect in the finished weld.
• "Run a test coupon first." Five minutes of dialing in saves an hour of chipping bad welds off a project.