Shielded Metal Arc Welding (SMAW): The Complete Guide

It’s 6:40 on a Saturday morning, the wind is already gusting across the driveway, and a cracked hinge on the stock trailer has to be fixed before the cattle move. The MIG welder is inside, useless without a calm shop and a clean gas shield. What comes out of the truck instead is a leads-and-stinger kit, a handful of E7018 rods, and a chipping hammer. That is shielded metal arc welding in its natural habitat: dirty steel, moving air, real deadlines.

Why Shielded Metal Arc Welding Still Matters in a Wire-Fed World

It’s 6:40 on a Saturday morning, the wind is already gusting across the driveway, and a cracked hinge on the stock trailer has to be fixed before the cattle move. The MIG welder is inside, useless without a calm shop and a clean gas shield. What comes out of the truck instead is a leads-and-stinger kit, a handful of E7018 rods, and a chipping hammer. That is shielded metal arc welding in its natural habitat: dirty steel, moving air, and real deadlines.

At its core, shielded metal arc welding (SMAW) is a manual arc welding process that uses a flux-coated, consumable electrode to create an arc between itself and the base metal, producing both a weld pool and its own protective shielding. More commonly known as “stick welding”, it goes by yet another name depending on where you’re at. This is exactly why the process has earned its staying power, and the reasoning behind it can be found in the many advantages of stick welding to this day.

The Roots That Built Its Reliability

While the electric arc itself was observed long before modern welding, it wasn’t nearly consistent enough for industrial work. The real leap came from the development of the flux-coated electrode. Swedish engineer Oscar Kjellberg is widely credited with developing the practical flux-coated electrode around 1904, the same era in which ESAB was founded. These coated electrodes made arc welding reliable enough for widespread industrial use, including rapid shipbuilding during the two world wars. From there, the process slowly trickled its way from naval yards and fabrication shops, all the way to the bed of a truck for weekend repairs.

It’s through organizations such as AWS that the practices surrounding this process would later be standardized, allowing the rough craft from those shipyards to evolve into a code-recognized, inspectable trade.

Where Stick Still Holds Its Ground

With all of the advancements made in wire-fed processes, it’s only natural to ask why SMAW is still around. The answer is a simple one: not every job is set up for a cylinder of shielding gas. You’ll still find stick welding as the default on structural steel erection, pipeline tie-ins, maintenance and repair, shipyards, rural fabrication, and confined or windy sites where a gust of wind would break a gas shield in an instant.

For many of these jobs, the steel isn’t freshly milled or perfectly clean. More often than not, there’s a bit of rust, mill scale, or grime to work with. This is where SMAW shines. Its core reputation of being slow but forgiving, cheap to start, and tolerant of rust and draft has kept it relevant for decades. For heavy field work, this is exactly one of the reasons you’ll see it relied on for demanding jobs, such as those covered in AJ marine welding.

Who This Guide Is For and What To Expect

This article is built for a wide range of readers. Whether you’re a hobbyist fixing equipment in your driveway, an apprentice learning the trade, a maintenance tech looking to get a repair done right, or an engineer and inspector who needs to read a WPS, the information here is meant to be practical and applicable to all of them.

Over the rest of this guide, we’ll walk through how SMAW works, the equipment and electrodes that go along with it, technique, joint preparation, its place amongst other processes, safety, troubleshooting, and the mistakes that cost the most time and money. The goal isn’t to crown a “winner” between processes, it’s to show you exactly when that little box of rods in the back of a truck is still the smartest tool for the job.

How SMAW Works: Arc, Slag, and a Constant-Current Circuit

Strip away the stinger, the sparks, and the smell of burning flux, and shielded metal arc welding is a circuit with a gap in it. Knowing that circuit separates the welder who turns the dial until it sounds right from the one who knows why.

The Complete Loop

• Power source — converts mains or engine power into welding current at a controlled voltage.
• Electrode cable — carries current to the holder; long, undersized cables rob amps through resistance.
• Electrode holder (stinger) — an insulated clamp gripping the bare end of the rod.
• Consumable electrode — melts into the joint; its coating does five jobs.
• The arc — the ionized gas path where electrical energy becomes heat.
• Weld pool — molten base metal plus filler, shielded by gas and slag.
• Work lead and clamp — the return path; a dirty ground is the most common cause of “the machine is broken.”

Break any link and the arc dies. That single idea explains most troubleshooting.

Why the Machine “Droops”: Constant Current Explained

SMAW runs on a constant-current (drooping) characteristic. A MIG machine holds voltage steady and lets amperage swing; a stick machine does the opposite. It sets an amperage target and drops voltage steeply as current rises, so when arc length changes, amperage barely moves. That matters because a human hand cannot hold a 3 mm gap — you will drift between 2 mm and 6 mm. With a drooping curve, that drift changes voltage a lot but current only slightly, so heat input stays predictable and the rod does not fuse itself to the plate.

Two voltages matter here:

• Open-circuit voltage (OCV) — the potential before the arc is struck, typically 50–90 V. This is the shock hazard, which is why OSHA 1910.254 caps open-circuit voltage for manual arc welding at 80 V for AC machines and 100 V for DC machines.
• Arc voltage — the running voltage once the arc is established, normally 20–30 V. That collapse from OCV is the droop doing its job.

The Coating’s Five Jobs

1. Shielding gas generation — the flux burns and releases CO₂, CO, and hydrogen-bearing gas that pushes air away from the pool.
2. Slag formation — molten flux floats on the puddle and freezes into a glassy shell that slows cooling and blocks oxygen and nitrogen.
3. Arc stabilization — potassium and sodium compounds ionize easily, keeping the arc steady, especially on AC.
4. Alloying and deoxidation — manganese and silicon tie up oxygen and sulfur, improving toughness and soundness.
5. Deposition and positional behavior — iron powder raises deposition rate; other additions make the slag freeze fast enough to hold overhead.

Cellulose versus limestone is the big fork in the road. Cellulose coatings (E6010, E6011) decompose into a forceful, fast-freezing gas shield with a thin slag — exactly why they own pipeline root passes. Limestone-based, low-hydrogen coatings (E7018) give a thicker, slower-freezing slag and much less hydrogen. That hydrogen difference is not trivia: diffusible hydrogen in steel can crack a weld days after you walk away, which is why E7018 demands a sealed can or a holding oven.

Polarity: Where the Heat Lands

Roughly two-thirds of the arc heat is released at the positive terminal, and that fact drives most polarity decisions:

Polarity	Heat balance	Result
DCEN (electrode negative)	Two-thirds of heat at the workpiece	Deeper penetration, narrower bead, less cleaning
DCEP (electrode positive)	Two-thirds of heat at the electrode	Shallower penetration, better oxide cleaning, faster melt-off
AC	Alternates each half-cycle	Middle ground; needs stabilizers in the coating; less arc blow than DC

Electrodes are polarity-restricted because the coating chemistry was designed around one heat balance. Run E6010 on DCEP and it runs badly; run E7018 on DCEN and you lose penetration and arc stability. Always check the manufacturer’s data sheet, and see the all-position welding rod guide for how position and polarity interact.

Duty Cycle, Efficiency, and Where the Metal Goes

Duty cycle is the percentage of a ten-minute window a machine can run at a given amperage — 60% at 200 A means six minutes of arc, four of cooling. Arc efficiency for SMAW is high, around 80%, because most arc energy reaches the joint. Deposition efficiency is another story: roughly 60–70% of the melted electrode becomes weld metal, with the rest leaving as spatter, slag, and stub ends. Wire processes waste far less, which is a real cost the cheap-rod argument ignores. For more on where SMAW still wins, read the advantages of stick welding.

Quick Reference: Typical SMAW Values

Parameter	Typical Range	Notes
Open-circuit voltage	50–90 V	OSHA caps: 80 V AC, 100 V DC
Arc voltage	20–30 V	Longer arc = higher voltage, more spatter
Amperage, 2.5 mm (3/32″)	70–110 A	Follow the electrode data sheet
Amperage, 3.2 mm (1/8″)	90–150 A	Most common repair size
Amperage, 4.0 mm (5/32″)	130–200 A	Check duty cycle at this output
Travel speed	100–250 mm/min	Set by bead shape, not by the clock

With the circuit understood, the next question is what hardware actually delivers it — machines, cables, holders, and the setup that keeps all of it honest.

The SMAW Kit: Machines, Cables, Holders, and Safe Setup

Stick welding is the least fussy arc process on the planet, but it is not equipment-free. A machine that cannot hold arc voltage, a corroded ground clamp, or a cracked cable jacket will ruin a weld just as thoroughly as bad technique. The good news is that the whole kit is short, cheap, and easy to inspect once you know what each part does.

Power Sources: Which Box Is Right for You

• AC transformer “buzz box”: The classic gray lunchbox. Cheap, tough, almost nothing to break. AC only, which makes some rods (E6010, E7018) hard or impossible to run.
• AC/DC transformer-rectifier: Adds a rectifier so you get DCEN and DCEP. Heavier and pricier, but it unlocks the full electrode catalogue and smoother arcs.
• Inverter: Light enough to carry one-handed, runs happily off modest generators, and usually gives better arc control plus hot-start and arc-force adjustments. More electronics to fail and more sensitive to dirty power.
• Engine-driven: A generator and welder in one for pipeline, farm, and remote structural work. Highest cost, highest capability.

For a hobbyist or maintenance tech, a 200 A inverter or an old AC/DC transformer covers nearly everything. Portability matters more than people expect — a machine you can lift gets used. That is a big part of why stick welding still wins on repair work.

Reading a Nameplate Without Guessing

Every machine gives you three numbers that matter: input voltage and current draw, output amperage range, and duty cycle. Duty cycle is rated at a specific amperage and ambient temperature, often 40 °C (104 °F). A “60% at 200 A” rating means six minutes of actual arc time in every ten at that output, with four minutes of cooling. Weld continuously above the rated amperage and the thermal overload will trip — or the machine will age fast.

Cables, Holders, and the Ground Clamp

OSHA 1926.351 requires arc welding cables to be fully insulated and flexible, and it prohibits splices within 10 ft (3 m) of the electrode holder end. Inspect jackets every time you uncoil — exposed copper near the stinger is a shock and arc-strike hazard, not a minor cosmetic issue. Holders are rated by amperage; a 200 A holder on a 300 A machine will cook itself.

Cable size (AWG)	Typical amperage ceiling	Sensible run
#6	~160–200 A	Under 50 ft
#4	~200–250 A	Up to 75 ft
#2	~250–300 A	Up to 100 ft
1/0	~300–350 A	Up to 150 ft

Treat that table as a starting point and confirm against your machine’s manual — long, thin leads drop voltage and make a hot machine feel weak. Also note that OSHA requires machine frames to be grounded and forbids using gas or flammable-liquid piping as a ground return.

Small Tools That Earn Their Space

A chipping hammer, a stiff wire brush, and a slag pick handle 90% of cleanup. Add magnetic squares, locking pliers or C-clamps, a fire blanket, and either a bucket of dry sand or a rated extinguisher within arm’s reach. Keep a spare stinger and a couple of dry rags in the box too.

PPE: What Actually Protects You

An auto-darkening helmet saves a hundred nods a day, but the shade number matters more than the brand. Filter shade scales with amperage: roughly shade 10 in the 60–160 A range, 11–12 at 160–250 A, and 12–14 above 250 A. Confirm against the current OSHA filter-lens table in 1926.351 and the helmet manufacturer’s guidance. Wear leather gauntlets, a jacket or sleeves, an apron, and boots — sparks find collars and cuffs. Add hearing protection when grinding or chipping, and remember that NIOSH treats welding fume as a genuine respiratory hazard, so ventilation or a respirator belongs in the kit, not on the wish list.

Pre-Arc Setup Checklist

1. Inspect cables, stinger, and ground clamp for cracks or exposed copper.
2. Confirm polarity and amperage match the electrode you are about to run.
3. Grind a bare, bright ground spot and clamp it close to the joint.
4. Check electrode condition — dry, undamaged coating, correct storage.
5. Clear combustibles within 35 ft and stage the extinguisher or fire blanket.
6. Suit up: helmet, gloves, sleeves, boots, eye and hearing protection.
7. Set up screens to protect bystanders, then strike an arc on scrap to verify.

Ten minutes of setup beats an hour of diagnosis. Every item on that list removes a variable you would otherwise be chasing later.

Electrode Codes Decoded: E6010, E6011, E6013, E7018, and Friends

The rod you pull from the tube decides more about the weld than the machine, the amperage dial, or the angle of your stinger. Each electrode is a small engineered system: a steel core wrapped in a mineral coating blended for a specific job in a specific position. Learning to read the code turns that mystery into a decision you can make in seconds.

The governing standard is AWS A5.1, published by the American Welding Society, which covers mild steel covered arc welding electrodes. Stainless and cast iron sit in their own specifications, but the logic is similar.

Reading the Digits, One at a Time

Take E7018 and break it apart:

• E means electrode: a consumable that carries the current and becomes part of the weld.
• 70 is minimum tensile strength in thousands of psi, so 70,000 psi, or roughly 485 MPa.
• 1 is the position digit: 1 means all positions, 2 means flat and horizontal fillet only, 3 means flat only.
• 18 is the coating and usability code: a low-hydrogen, iron-powder coating that runs on AC or DCEP.

So E7018 is a covered electrode with 70,000 psi minimum tensile strength, usable in all positions, with a low-hydrogen iron-powder coating run on AC or DCEP. That single line tells you most of what you need before you strike an arc.

The Comparison Table You’ll Actually Use

Electrode	Coating	Current	Positions	Penetration	Deposition	Best use
E6010	Cellulose-sodium	DCEP only	All	Deep	Moderate	Pipe roots, dirty or rusty repair
E6011	Cellulose-potassium	AC or DC	All	Deep	Moderate	Same as 6010, but on AC buzz boxes
E6012	High titania sodium	AC or DCEN	All	Shallow	Moderate	Sheet metal, poor fit-up, gap filling
E6013	High titania potassium	AC or DC	All	Shallow to medium	Moderate	General light fabrication, hobby work
E7014	Titania with iron powder	AC or DC	All	Medium	High	Higher current on thin-to-medium steel
E7018	Low-hydrogen, iron powder	AC or DCEP	All	Medium	High	Structural steel, code work, critical joints
E7024	High iron powder, high titania	AC or DC	Flat, horizontal fillet	Shallow	Very high	Production flat welding and long fillets
E7028	Low-hydrogen, iron powder	AC or DCEP	Flat, horizontal fillet	Medium	Very high	Heavy flat structural fabrication
308L	Stainless, low carbon	AC or DCEP	All	Medium	Moderate	304/304L stainless, dissimilar steel joints
309L	Stainless, high ferrite	AC or DCEP	All	Medium	Moderate	Dissimilar metals, stainless to carbon steel
ENi-CI	Nickel, graphite	AC or DCEP	All	Low	Low	Cast iron repair, cold joints, short beads

Electrodes are not ranked from bad to good; they are matched to a job. E6013 is a poor choice for a pipeline root and a fine choice for a gate frame. E7018 is the default for structural work and a miserable choice for a rusty, painted trailer hinge where you cannot clean to bare metal. Selecting a rod is part of the fit-up decision, not an afterthought. There is also a case for the softer, slower approach on light material; the reasons laid out in why stick welding still wins on real jobs are mostly about tolerance, not speed.

Low-Hydrogen Electrodes and the Cracking They Prevent

Hydrogen is the quiet saboteur of steel welds. Moisture in an electrode coating breaks down in the arc and deposits hydrogen into the weld metal. That hydrogen migrates into the heat-affected zone, collects in tiny voids, builds pressure, and can crack the steel hours or days later. The failure is called underbead or cold cracking, and it almost never appears while you are still welding. That delay is what makes it dangerous.

E7018 limits the problem with a limestone-based coating that produces very little hydrogen and a slag that shields the puddle well. The H in AWS A5.1 supplemental designators quantifies the protection. H4, H8, and H16 indicate maximum diffusible hydrogen of 4, 8, or 16 millilitres per 100 grams of deposited weld metal. Lower is better for crack-prone steel.

But a low-hydrogen electrode only stays low-hydrogen if you keep it dry. Open a can of E7018 on a humid morning, leave it on the bench for a week, and it absorbs moisture from the air. AWS D1.1 requires low-hydrogen electrodes to be stored and handled to keep them dry: sealed cans until use, then a holding oven typically around 250°F (120°C), with rebaking per the manufacturer’s instructions if they have picked up moisture. Electrodes exposed beyond the manufacturer’s time limit should be discarded or rebaked, not gambled with.

High-Iron-Powder Electrodes: Deposition at a Price

Some coatings carry iron powder that becomes part of the weld metal instead of turning into slag. The result is a much higher deposition rate and a smoother bead, which is why E7024 and E7028 exist. The trade-off is a heavy, fluid slag pool that gravity will not let you fight. E7024 is limited to flat and horizontal fillet work because its heavy slag simply does not support out-of-position welding. Point it uphill and the puddle sags into a mess.

That limitation is not a flaw; it is a design decision. On a shop floor laying long flat fillets on heavy plate, a high-iron-powder rod will outrun a 7018 all day. On a ladder in the wind, it is useless.

Matching Electrode Size to Amperage

Diameter and current travel together. Too little current for the size and the arc stutters and sticks; too much and you burn through, undercut, or lose the coating.

Diameter	Typical amperage range	Common use
3/32 in (2.4 mm)	40–90 A	Thin sheet, root passes, tight work
1/8 in (3.2 mm)	75–140 A	The everyday all-rounder
5/32 in (4.0 mm)	110–190 A	Medium plate, fill passes
3/16 in (4.8 mm)	150–250 A	Heavy plate, flat production
7/32 in (5.6 mm)	200–320 A	Very heavy sections, flat only

Treat these as starting points, not rules. Check the manufacturer’s range for the specific classification, then fine-tune by watching the arc. A code qualification, such as the requirements invoked around OSHA’s welding and cutting rules for construction, may also impose electrode handling requirements beyond the rod’s spec sheet.

Selection Logic in Five Questions

1. Base metal: mild steel, stainless, cast iron, or something with alloy content? This picks the family. For alloy work, the guidance in selecting alloy steel electrodes matters more than preference.
2. Thickness: thin sheet points to 6013 or 6012 at low current; heavy plate needs 7018 or a high-deposition rod.
3. Position: overhead or vertical work eliminates 7024 and 7028 immediately.
4. Available current: an AC-only buzz box rules out E6010, which is restricted to DCEP.
5. Governing code: structural work under AWS D1.1 usually pushes you toward low-hydrogen electrodes with documented storage.

Get those five answers and the electrode chooses itself. The rest is practice, and the rods you practice with shape everything you learn next. That is why the all-position rod guide is worth reading before you buy a ten-pound tube of anything.

Dialing In: Amperage, Arc Length, Angle, and Travel Speed

With the machine set up and the right rod in hand, shielded metal arc welding comes down to a handful of inputs the puddle will always judge you by: amperage, arc length, electrode angle, travel speed, and position technique. The dial on the front of your machine is only a starting point. Your eyes and ears are the true meters.

Finding Your Sweet Spot With Amperage

Amperage is the foundation for every other variable. For mild steel stick electrodes, a widely used starting estimate is roughly 30 A per 1/32 in (0.8 mm) of electrode diameter, adjusted within the manufacturer’s published range. From there:

Electrode Diameter	Typical Amperage Window (Mild Steel)	Notes
3/32 in (2.4 mm)	70 – 100 A	Great for thin plate and out of position control.
1/8 in (3.2 mm)	90 – 140 A	The most versatile and commonly practiced size.
5/32 in (4.0 mm)	130 – 190 A	Better for heavier material, but much less forgiving out of position.

Exact values are dictated by the electrode classification, so treat these as a launch pad, not a law. Read the puddle instead of the number: if the rod sticks on every strike and the puddle sits sluggish, you’re too cold. Excessive spatter, an uncontrollably wide puddle, or burn-through means you’re too hot. Learning those cues is worth more than chasing a perfect digit on the dial.

Arc Length, Angles, and Drag Technique

Once amperage is in the ballpark, arc length is your fine adjustment. A short arc, keeping the electrode only a fraction of its diameter off the puddle, gives the most stable arc, the best penetration, and the least spatter. A long arc raises arc voltage, throws more spatter, and lets atmosphere into a larger unshielded gap. For most SMAW work, less gap is better.

Angles matter just as much. On flat and horizontal joints, a travel angle of about 10 to 15 degrees in the direction of travel, with a slight work angle toward the joint, keeps the puddle directed where you want it. Stick is almost always a drag process: the electrode is pulled, not pushed, so the flux coating can shield the arc and the slag can flow behind the puddle to protect solidifying metal. Pushing with stick usually means poor shielding and a very uncooperative arc.

Welding the Four Positions

Gravity becomes your opponent the moment you leave flat. The goal isn’t to fight it but to manage puddle size against it. Knowing which rods count as an all position welding rod helps, but technique is always the deciding factor.

• Flat (1G/1F): The easiest position. Wider, more fluid beads work here with minimal puddle manipulation.
• Horizontal (2G/2F): The puddle wants to sag down the plate. Keep a tighter arc, a smaller puddle, and avoid wide weaves to prevent rollover.
• Vertical (3G/3F): On thicker material, vertical-up with a slight weave and controlled puddle time generally gives better penetration and fusion than vertical-down. Vertical-down suits thin sheet, where the faster travel limits heat input and burn-through.
• Overhead (4G/4F): The most punishing position. Smallest manageable puddle, very tight arc, and patience. Excess metal has nowhere to go but back down.

Weave width has a limit too: never exceed roughly 2-3 times the electrode diameter, since wider weaves raise heat input and the odds of trapping slag.

Starts, Restarts, Craters, and Travel Speed

A perfect bead can be ruined by a careless start or an unfilled crater. With E7018 in particular, use the hot-start and restart features if your machine has them, or a quick, controlled tap start to establish the arc without sticking. When restarting over an existing bead, feather the new arc slightly ahead of the crater, pause to melt the tie-in, then blend into your travel to avoid a cold lap.

Crater filling cannot be skipped. At the end of any pass, pause at the tail of the puddle long enough for it to fill, then break the arc gently. An open, unfilled crater is a stress concentration point and one of the most common places for cracking to start.

Travel speed ties it all together. Too fast narrows the bead, reduces fusion, and promotes undercut. Too slow piles metal, overheats the joint, and increases distortion. The right speed is the one where slag flows continuously behind a clear, visible puddle, not racing ahead of you and not drowning you in molten metal.

Practice Ladder to Build Muscle Memory

1. Stringer beads on plate: Flat position stringers on clean scrap mild steel. Focus only on arc length and travel speed.
2. Lap joints: Tie into two pieces of metal and watch your work angle, since the puddle favors the thicker plate.
3. T-joints (fillets): The most common field joint, and the fastest way to expose puddle control problems.
4. Open-root work: Only once the first three are consistent, move to beveled plate with an open root. Follow all applicable safety precautions, including the ventilation practices in OSHA 1910.252 for hot work.

Joint Preparation, Fit-Up, and the Defects That Follow

In shielded metal arc welding, the arc is only half the battle. Most failed beads can be traced back to what happened before the stinger came to life. Good fit-up makes the weld easier to run and prevents the majority of discontinuities that would otherwise mean costly repair.

Joint Types, Bevels, Root Faces, and Preparation

Every joint suits the load it carries. Stick work leans on butt joints for full penetration, lap joints for overlapping plate, T joints for cross members, corner joints for boxed sections, and edge joints for thin plate built up against itself.

Thicker material needing full penetration gets a bevel ground into one or both plates. Watch four dimensions: the bevel angle, the root face (the small flat land at the bottom of the bevel), the land, and the root gap between the pieces. These numbers come from the welding procedure, not from guesswork. Cut prep with a grinder for precision, an oxy-fuel torch on heavy plate, or plasma for faster, cleaner edges. The same fit-up logic carries over to thinner and specialty metals such as those covered in Aluminum Boat Welding: The Complete Guide for Strong Hull Joints, just with adjusted prep.

Cleaning, Contaminants, and the Galvanizing Hazard

No amperage setting will fuse through contamination. Before tacking, joint faces must be free of mill scale, rust, paint, oil, and moisture. Even a thin oil film can break down into hydrogen and leave porosity behind, and damp plate is one of the easiest ways to push hydrogen into a carbon steel weld.

Galvanized steel is the big outlier. Heat from the arc vaporizes the zinc coating into zinc oxide fume, the classic cause of metal fume fever and its flu-like symptoms hours after exposure. Ventilation or respiratory protection is required under OSHA 1910.252, and wherever possible the coating should be ground away from the weld zone first. Never weld or grind galvanized work in a cramped, unventilated space.

Tacking, Distortion Control, and Shrinkage

Once parts are clean and fitted, tacks hold alignment for the final passes. Spacing, size, and count depend on the joint, but tacks must be weldable quality. A cracked or undersized tack becomes a crack propagation point.

As molten steel cools it shrinks, dragging the joint out of line. Fight back with proven methods: backstep welding against the overall direction of travel, a balanced sequence on both sides of the joint, pre-set (deliberately angling parts to offset pull), clamps, and skip welding to spread heat input. Managing heat at fit-up is always cheaper than correcting it with a torch afterward.

The Defect Encyclopedia

Knowing what to look for matters as much as running a good bead. The frequent offenders in SMAW are porosity (gas pockets from moisture or contamination), slag inclusions (trapped slag from poor interpass cleaning or a long arc), incomplete fusion (no bond between passes or to the base metal), incomplete penetration (failure to reach the root, often from a tight root gap or low amperage), undercut (a groove melted into base metal), overlap (weld metal rolled over without fusing), spatter, arc strikes outside the joint, and cracks: hot cracks during solidification, cold or hydrogen-assisted cracks that show up hours or days later, and lamellar tearing in restrained rolled plate. Add distortion from uncontrolled shrinkage.

Inspection, Acceptance, and First Corrective Action

Not every imperfection is rejectable. Visual inspection comes first and catches surface discontinuities like undercut, overlap, cracks, and arc strikes, but it cannot see inside. Where the code requires it, radiography (RT) or ultrasonic testing (UT) looks for internal flaws, while liquid penetrant (PT) and magnetic particle (MT) find tight surface and near-surface defects.

Those requirements come from specific codes. AWS D1.1 covers structural steel, ASME Boiler and Pressure Vessel Code Section IX covers procedure and welder qualification for pressure equipment, and API 1104 covers pipeline welding. Acceptance criteria are never a judgment call; they belong to the governing code for that job.

Defect	Likely Cause	First Corrective Action
Porosity	Moisture, oil, rust, or damp electrodes	Clean to bare metal; use dry, properly stored electrodes.
Slag Inclusions	Long arc, rushed travel, slag left between passes	Chip and wire brush between passes; shorten arc length.
Incomplete Fusion/Penetration	Low amperage, tight root face or gap, poor angle	Restore procedure fit-up dimensions; set amperage to electrode.
Undercut/Overlap	Excess current, wrong travel speed or angle	Reduce amperage, correct work and travel angle, refine speed.
Cracks (Hot/Cold/Hydrogen/Lamellar)	Restraint, hydrogen, high carbon, poor preheat	Stop, evaluate to code, apply preheat and low-hydrogen practice; repair only by qualified procedure.
Arc Strikes & Distortion	Striking outside the joint; unbalanced heat input	Grind arc strikes to sound metal; use backstep, clamps, or balanced sequence.

Sound SMAW starts long before the arc. A clean joint, correct fit-up, deliberate heat control, and an eye for flaws prevent most defects outright. When in doubt, check the governing code and lean toward prevention, because repairing an internal flaw found by RT or UT is always more work than getting the prep right the first time.

SMAW vs MIG, TIG, and Flux-Cored: An Honest Comparison

There is no single “best” welding process. Each one is built to solve a different problem, and what works flawlessly in a shop can fall apart on a windy job site. The key is to judge them by the job at hand, not by preference.

Factor	SMAW (stick)	GMAW (MIG)	FCAW	GTAW (TIG)	SAW
Equipment cost	Low	Low to moderate	Moderate	Moderate to high	High
Portability	Excellent; generator-friendly	Good indoors; needs gas	Good; self-shielded needs no gas	Fair; gas and fragile torch	Poor; heavy and shop-bound
Deposition rate	Low; typically low single-digit lb/hr	Moderate to high	High, especially dual-shield flat	Low	Very high
Out-of-position	Excellentwith the right electrode	Good; settings matter	Good; self-shielded especially	Excellent in skilled hands	Flat and horizontal only
Wind tolerance	Excellent	Poor; gas shield blows away	Excellent self-shielded; poor dual-shield	Poor	Poor outdoors
Cleanliness needed	Low; tolerates rust and scale	High	Moderate	Very high	Moderate to high
Fume generation	Moderate to high	Moderate	High	Low	High
Skill curve	Moderate; arc reading essential	Low to moderate	Moderate	High	High setup knowledge
Typical applications	Repair, structural steel, pipeline, field work	Sheet metal, auto body, light fabrication	Structural, heavy fabrication, field work	Thin metals, stainless, aluminum, aerospace	Pipe mills, pressure vessels, long seams

Where Stick Welding Still Wins

Stick wins because it carries its own shield. There is no gas cylinder to drag up a ladder and no wire feeder to clog. The electrode coating creates the shielding gas and the slag cap, so the process keeps working on rusty steel, painted edges, and dirty repair work where other processes complain. It also shrugs off wind. Gas-shielded GMAW is vulnerable to draft because the shield literally blows away, while SMAW and self-shielded flux-cored wire tolerate outdoor conditions far better. That is why stick remains common in structural erection, pipeline tie-ins, shipyards, rural fabrication, and maintenance work. The practical advantages of stick welding are less about speed than about showing up and finishing the job.

Where SMAW Loses Badly

Thin sheet is a fight. Stick welding concentrates heat in a small area and easily burns through 20-gauge material. High-production fabrication is another weak spot: SMAW deposition rates typically sit in the low single digits of pounds per hour, while high-iron-powder electrodes and flux-cored wire can substantially exceed that in flat positions. Aluminum is largely off the table for routine stick work, since the process lacks the clean, alternating-current arc and dedicated fillers that aluminum demands; most shops turn to aluminum MIG welding instead. Cosmetic work also suffers. Slag, spatter, restart marks, and chipping hammer scars are part of the deal.

Cost per foot deserves honesty. The machine and electrodes are cheap, but SMAW deposition efficiency is commonly quoted around 60–70% because spatter, slag, and electrode stubs consume part of what you bought. Stubs are typically discarded with roughly 2 in (50 mm) of unusable electrode, which is trivial on one repair and real money over a production run. Add chipping, brushing, and grinding, and the cheapest process can become the most labor-intensive one.

Flux-Cored: The Closest Industrial Competitor

FCAW is the process that most directly challenges stick on structural work. It feeds continuously, deposits faster, and can run outdoors when self-shielded. The distinction matters: self-shielded flux-cored wire generates its own shielding from the flux core and needs no gas, making it a field process. Dual-shield FCAW uses an external gas shield plus flux, produces smoother beads and higher deposition, and generally belongs indoors. Both generate significant fume, and the UK Health and Safety Executive treats welding fume as a serious health hazard regardless of process.

Which Process Should You Learn First?

Choose based on the work in front of you. Maintenance and structural repair point to SMAW. Production sheet metal points to MIG. Precision stainless, aluminum, or aerospace work points to TIG. That said, stick is an excellent teacher. It forces you to read the puddle, judge arc length by sound and sight, and manage heat without a wire feeder doing half the thinking. Those skills transfer directly to flux-cored and improve your MIG and TIG work too.

The verdict is not that stick beats everything. It is that stick remains unmatched for portable, forgiving repair work, while MIG, TIG, FCAW, and SAW each win in their own lane. Match the process to the dirt, the wind, the position, and the production volume, and the argument mostly disappears.

Fume, Radiation, Shock, and Fire: The Safety Chapter That Matters

Safety in stick welding is not a disclaimer tacked onto the last page. The process is a small open-air furnace: the coating burns, the metal boils, and a plume of fine particles rises straight into the welder’s breathing zone. The professional approach is engineering, not bravado. Identify the hazard, control it at the source, and use personal protective equipment as the last line of defence rather than the only one.

What Is Actually in the Plume

Welding fume is a mixture of metal oxides and fine particulates released from the electrode core, the flux coating, the base metal and anything sitting on its surface. The particles are largely submicron, so they stay airborne for a long time and travel deep into the lungs. What sounds like a simple grey cloud is chemically complex.

• Manganese: NIOSH lists a recommended exposure limit of 1 mg/m³ as an eight-hour TWA, with a 3 mg/m³ short-term limit, while the OSHA permissible exposure limit is 5 mg/m³ as a ceiling. Exposure has been associated with neurological effects, including mood and memory changes and reduced hand-eye coordination, according to NIOSH.
• Hexavalent chromium: stainless steel and hardfacing electrodes are the usual sources. OSHA’s chromium standard sets a permissible exposure limit of 5 micrograms per cubic meter as an eight-hour TWA, with an action level of 2.5 micrograms per cubic meter under 29 CFR 1910.1026.
• Nickel and zinc: nickel-bearing electrodes and stainless base metals add nickel to the plume. Zinc from galvanized steel causes metal fume fever, a flu-like illness that is acute rather than harmless. Iron oxide adds mass to the cloud but is not the only concern.

Electrode selection changes the recipe. Basic-coated low-hydrogen rods, rutile rods and stainless electrodes all produce different fume profiles, which is one reason alloy steel welding electrode selection is also a health decision.

IARC, HSE, and the End of “Mild Steel Is Fine”

The old assumption that only stainless fume was dangerous no longer holds. In 2017, the International Agency for Research on Cancer classified welding fumes as carcinogenic to humans, Group 1. The UK Health and Safety Executive has since required controls for mild steel welding fume, not just for stainless or special alloys; its guidance is clear that exposure should be controlled to as low a level as is reasonably practicable. The HSE welding guidance is worth reading before the next job, particularly for indoor work.

Control the Exposure

Follow the hierarchy of controls. Substitution comes first: strip paint, oil and galvanizing from the joint, and use a lower-fume process where the code and procedure allow. Engineering controls come next. Local exhaust ventilation should capture fume at the arc, not across the shop. Extraction guns, downdraft tables and movable hoods work only when positioned close to the plume. A fan that blows the cloud past your face is not ventilation; it is redistribution.

Administrative controls include rotating welders out of confined areas, scheduling heavy fume work when fewer people are nearby, and keeping the work area clean. Respiratory protection is the backup: a properly fitted half-mask or, better for long exposures, a powered air-purifying respirator. Fit testing is not optional paperwork. A leaking mask gives false confidence. OSHA’s welding and cutting requirements, including 1910.252, set the broader framework for ventilation and protection.

Arc Radiation and Electrical Shock

The arc emits intense ultraviolet and infrared radiation. UV causes “arc eye,” a painful inflammation that often appears hours after exposure, and it can burn exposed skin like sunburn. Use a welding helmet with the correct shade for the amperage, typically shade 10 to 13 for stick welding, and wear safety glasses underneath. Screens around the booth protect helpers and passers-by, not just the welder.

Electrocution is a real risk because the electrode holder is live whenever the machine is on. Open-circuit voltage is commonly in the 50–90 volt range, while arc voltage is roughly 20–35 volts; sweat, wet gloves and damp ground lower the body’s resistance. Keep gloves dry, inspect the holder for cracked insulation, replace damaged cable, and never weld while standing in water. OSHA 1910.254 covers arc welding equipment and grounding requirements.

Fire, Cylinders, and Confined Spaces

Hot work needs a permit on most sites. Clear combustible material from the area, protect openings and cracks where sparks can fall, and maintain a fire watch during the work and for a set period afterward. Thirty minutes is a common post-work baseline, but the permit and local fire code govern. Keep cylinders upright and secured, fit valve caps when moving them, and separate oxygen from fuel gas by distance or a barrier. Confined spaces require a permit, atmospheric testing, ventilation, an attendant and a rescue plan before anyone strikes an arc. Gouging and carbon arc work multiply these hazards, as covered in this guide to air arc welding and carbon arc gouging.

Troubleshooting Clinic and a Realistic Practice Plan

Every stick welder has produced a bead that looked respectable and then failed a bend test, or watched an arc that ran perfectly yesterday spit and stick today. The difference is rarely mysterious. It is usually one variable, found by working through the basics in a fixed order instead of changing five settings at once.

Diagnose in the Right Order

Start with the biggest and most common variable: the ground. A clamp on mill scale, paint, or a loose table connection causes more “bad machine” complaints than any internal fault. Then verify polarity and machine settings against the electrode manufacturer’s data. Moving from DCEP to DCEN, or from AC to DC, can transform arc behavior and penetration, so confirm the leads are where you think they are. Next check amperage, then electrode condition and storage, and only then technique. Change one thing, run a test bead, and record what happened.

Symptom	Probable causes	First checks	Corrective action
Bad arc start	Low current, damp electrode, poor ground, tentative strike	Ground, polarity, amperage setting	Clean the ground point, raise current slightly, strike firmly and lift to arc length
Electrode sticking	Current too low, wrong polarity, arc buried in the puddle	Electrode spec and amperage	Increase current, correct polarity, restart on clean metal
Porosity	Moisture, oil, paint, rust, excessive arc length	Electrode storage and joint cleanliness	Use fresh rods, grind to bare metal, shorten the arc
Wormhole porosity	Hydrogen from moisture, contamination, arc blow	Rod condition, base metal, ground placement	Dry or replace electrodes, clean the joint, reposition the ground
Spatter explosion	Current too high, damp coating, wrong polarity	Amperage and polarity	Reduce current, use dry electrodes, match polarity to the classification
Undercut	Excess current, long arc, fast travel, poor angle	Current and travel speed	Lower current, tighten the arc, pause briefly at the joint edges
Slag inclusions	Slag not removed between passes, low current, fast travel	Interpass cleaning and bead profile	Chip and brush thoroughly, adjust current and travel speed
Arc blow	Magnetic imbalance, ground far away, long arc	Ground location and arc length	Move the ground, shorten the arc, change work angle or add a tack
Erratic arc on AC	Loose connection, damaged cable, poor ground	Lugs, cable jacket, clamp contact	Tighten or replace connections and establish bare-metal contact
Machine or cables overheating	Duty cycle exceeded, undersized cables, loose lugs	Nameplate duty cycle and cable size	Let the machine cool, use shorter or larger cables, tighten lugs
Breaker tripping	Input supply too small, long extension cord, high current tap	Input voltage and circuit rating	Use a dedicated circuit and correct cord gauge
Bead looks good but fails bend	Incomplete fusion or penetration, slag, hydrogen cracking	Joint prep, root fusion, rod storage	Cut a section to inspect, improve prep and fit-up, follow the procedure

From Practice Plate to Qualification

Build skill in a deliberate sequence. Weeks one and two: arc starts, restarts, and straight stringer beads on flat plate, then overlapping beads. Week three: T-joints and lap joints, focusing on work angle and fusion at the root. Week four: butt joints with proper root gaps and consistent travel. Week five: vertical-up stringers and small weaves, keeping weave width controlled. Week six: horizontal and overhead work on scrap, where gravity exposes puddle-control weaknesses. Week seven: open-root practice if your process and electrodes suit it. Week eight: cut, bend, or visually inspect test plates and repeat the weakest joint.

Keep a logbook with date, machine, polarity, amperage, electrode class, diameter and lot number, joint details, position, preparation, appearance, test result, and the single change you will try next session. That record turns practice into measurable progress and mirrors how professionals document variables.

Procedure, Welder, and Career Context

A written procedure, the WPS, tells the welder how a joint should be made. Its supporting procedure qualification record, or PQR, documents the test that proved the procedure produces sound welds. A welder performance qualification is different: it tests the individual on a specific process, position, and joint configuration. Under AWS D1.1, structural welder tests commonly use limited-thickness groove and fillet specimens, and qualification is restricted to the positions and thicknesses tested. ASME Section IX applies similar logic through its own essential variables. For the plate-to-pipe transition, our all-position welding rod guide explains how electrode choice changes with position.

Credentials such as the AWS Certified Welder and Certified Welding Inspector are administered through the American Welding Society. Certification does not replace hands-on competence, but it proves that a welder or inspector has met a defined standard. The practical route is simple: build consistent beads, learn to diagnose your own defects, document your settings, and test yourself against the positions and thicknesses you intend to weld.

Common Mistakes, a Field Checklist, and the Bottom Line

Most stick welding failures are not exotic. They are ordinary oversights repeated under deadline pressure: a ground clamp on paint, a rod pulled from an open can, a dial set by habit. The fixes are equally ordinary, which is good news. A short checklist catches more defects than a new machine.

The Mistakes That Cause Most Failures

• Wrong polarity or a damp electrode. Running E7018 on the wrong current, or using a rod left open overnight, can produce a weld that looks fine and cracks days later. Storage discipline is a correctness issue, not housekeeping.
• Dirty joints and a long arc. Mill scale, paint, oil and rust cause porosity and fusion flaws. Holding a lazy arc adds spatter and loses penetration.
• Insufficient current or a poor ground. Both feel like a dying machine. Clean bare metal at the clamp and enough amperage for the joint usually restore the arc.
• Ignoring duty cycle. Thermal shutdown, tripped breakers and a mushy arc are overload symptoms, especially on small 120/240 V units. Let the fan finish its job.
• Welding galvanized or painted steel without controls. Zinc fume and burning coatings demand removal and ventilation, not a shrug.
• Skipping the fire watch. SMAW spatter travels well beyond the weld. A combustible-free zone and a fire watch are required hot work precautions under OSHA 1910.252.
• Never practicing out of position. Flat beads alone do not build vertical or overhead control. An all-position welding rod guide helps you choose the right electrode for the joint.

The One-Page Field Checklist

Phase	Check
Before	Confirm WPS, electrode condition and polarity. Set amperage. Clean to bare metal. Ground close and tight. Clear combustibles. Set fire watch and PPE.
During	Keep a short arc. Watch travel angle, speed and edges for undercut. Chip slag between passes. Respect duty cycle. Stop if the arc changes character.
After	Chip and brush. Inspect for porosity, cracks and incomplete fusion. Repair defects properly. Cool the part. Shut down and secure the area.

Back to the Trailer Hinge

On that windy Saturday, the experienced hand did not simply strike an arc. He ground a bright spot for the ground clamp, checked that the E7018 rods had been stored dry, cleaned the hinge to bare steel, and clamped it so the joint could not move. Then he tacked both ends, ran a short arc at a sensible current, and chipped the slag before inspecting the result. The difference was not talent. It was treating a rushed repair as a small procedure.

The Honest Verdict

SMAW remains unmatched for portable, forgiving structural repair. It is still the best teacher of puddle control and arc reading, and it is still worth learning properly. For code work, verify the current edition of the governing standard and the project’s WPS rather than trusting a generic settings chart; AWS is the place to start. If you want the wider case, read why SMAW still wins in the field.

Before the next job, open the electrode can, check the storage conditions, and ask where the fume will go. Those two habits prevent more failures than any last-minute adjustment at the stinger.

Frequently Asked Questions

What is shielded metal arc welding in simple terms?

Shielded metal arc welding is an arc process that uses a flux-coated consumable electrode held in a clamp. The arc melts the electrode and the workpiece, while the coating burns to create shielding gas and a slag layer that protects the cooling weld. It is the same process most people call stick welding.

Is SMAW the same as stick welding?

Yes. Stick welding, SMAW and manual metal arc welding all describe the same process; ‘MMA’ is simply the term used in ISO and European standards. Any difference you see is terminology, not technique or equipment.

Which electrode should a beginner start with?

E6013 is the easiest starting point on clean, thin-to-medium mild steel because it restarts readily and tolerates a slightly long arc. Once you can run consistent beads, move to E7018 to learn low-hydrogen handling and out-of-position work, or to E6010 if you are heading toward pipeline and root-pass work.

Can I stick weld with a 120-volt machine?

Yes, but expect limits. Most 120 V units top out around 90-140 A and have low duty cycles, which suits 3/32 in electrodes and material up to roughly 1/8 in. For 1/8 in and larger electrodes or thicker steel, a 240 V input machine is far more practical.

Why does my electrode keep sticking to the plate?

Sticking almost always means too little current, a contaminated or damp electrode, or a ground connection that is not clean bare metal. Increase amperage slightly within the manufacturer’s range, verify polarity, and grind the ground point to bright metal before changing technique.

Do I need to store E7018 electrodes in an oven?

Low-hydrogen electrodes must stay dry. Keep unopened cans sealed, hold opened electrodes in a heated cabinet, and follow the manufacturer’s redrying instructions. Codes such as AWS D1.1 also set limits on how long electrodes may be exposed to ambient air before redrying is required.

Is stick welding safe indoors?

Only with proper ventilation. Welding fume contains metal oxides and process-dependent contaminants such as manganese and hexavalent chromium, and IARC classifies welding fume as carcinogenic to humans. Use local exhaust ventilation or supplied air, and never weld in a confined space without a permit and atmospheric testing.

Which is stronger, stick or MIG?

Strength comes from procedure and execution, not the process name. A properly qualified SMAW weld on structural steel routinely meets the same code requirements as a qualified MIG weld. SMAW tends to be more tolerant of surface contamination and wind, while MIG offers speed and easier thin-sheet work.

How long does it take to learn stick welding?

Most people can run a passable flat bead after a few focused sessions, but consistent out-of-position work with good fusion usually takes months of deliberate practice. Structured practice on stringers, T-joints and open roots, with each bead inspected and logged, shortens the curve considerably.

What does the ’18’ in E7018 mean?

In the AWS A5.1 system, the final two digits encode coating type, current and usability. For E7018, that combination indicates a low-hydrogen, iron-powder electrode that runs on AC or DCEP and is usable in all positions.