Welding 7018 Vertical Up: The Complete Technique Guide

The coupon came back from the test booth with a red mark along the left toe, and the instructor’s words stung: ‘Porosity and undercut — run it again.’ It is a scene every structural welder remembers, because vertical-up 7018 is the position that separates hobbyists from people who get paid to weld beams and pressure work. The good news: once you understand why the puddle behaves the way it does uphill, the rod starts to feel almost cooperative instead of stubborn.

Why 7018 Vertical Up Is the Skill Every Structural Welder Is Judged On

The coupon came back from the test booth with a red mark along the left toe, and the instructor’s words stung: “Porosity and undercut — run it again.” It’s a scene every structural welder remembers, because vertical-up 7018 is the position that separates hobbyists from people who get paid to weld beams and pressure work. The good news: once you understand why the puddle behaves the way it does uphill, the rod starts to feel cooperative instead of stubborn.

This guide answers the question that sends most beginners to YouTube at midnight: what exactly is 7018 vertical up, and why does it matter so much? From there you’ll get rod angles, amperage ranges, weave mechanics, defect diagnosis, and a practice plan you can actually follow. But first, the foundation.

What Is 7018 Vertical Up?

E7018 is a low-hydrogen stick electrode classified under the AWS A5.1 specification. The code decodes neatly: 70 means a minimum tensile strength of 70,000 psi (about 480 MPa), 1 means the rod is rated for all welding positions, and 8 indicates a low-hydrogen basic covering — the reason this rod dominates structural work. Per the classification system explained in an NRC welding training module, that “1” digit is what legally permits you to weld overhead and vertically with the rod. Not every electrode earns it.

Lincoln Electric’s Excalibur 7018 MR data lists a minimum tensile strength of 70,000 psi (480 MPa), a minimum yield of 58,000 psi (400 MPa), and 22% minimum elongation — numbers that make it a staple for anything structural. Lincoln lists its 7018 stick electrodes as suitable for “all positions except vertical down,” which is precisely why uphill is the standard progression for this rod.

“Vertical up” simply means the weld progresses from the bottom of the joint upward, climbing against gravity. In certification terms, that’s 3G (groove weld in the vertical position) or 3F (fillet weld in the vertical position). “Uphill” and “vertical up” mean the same thing.

Why Every Structural Welder Gets Judged on This

Here’s the practical reality: when you walk into a certification test or a field-erection job, the vertical-up groove weld is the test piece. It’s the position where inspection is strictest, where the consequences of a bad root pass are hidden inside the joint, and where employers can tell within thirty seconds whether a welder understands puddle control or is just hoping.

The reason is physics, and ESAB puts it plainly: vertical stick welding is harder than flat because gravity pulls the molten pool downward, increasing the risk of imperfections and slag inclusions. In flat work, gravity helps the puddle settle. Uphill, it works against you constantly. Every bead you lay has to solidify fast enough to become a shelf — a small ledge of solid metal — that the next increment of molten pool sits on. Build the shelf well, and the weld climbs. Build it poorly, and the pool sags, traps slag, or rolls over itself into cold lap.

That’s the core challenge of this article: gravity pulls the molten pool down, so the welder must build a shelf of solidified metal and step onto it. Every technique that follows — rod angle, arc length, step size, weave rhythm — exists to serve that one idea.

Where You’ll Actually Use It

This isn’t a niche skill. Vertical-up 7018 shows up across the work that holds cities together:

• Building columns and structural frames — where moment connections and full-penetration grooves are welded in place, not on a bench.
• Gusset plates and bracing on bridges and seismic-rated structures.
• Pipe supports and structural pipe racks in refineries and power plants.
• Heavy equipment repair — excavator booms, loader arms, mining frames.
• Field erection, where the joint is fixed in space and only your body position moves.

In all of these, the joint is often too big, too thick, or too inaccessible to weld any other way. The 7018 uphill bead is how the industry handles them.

Who This Guide Is For

If you’re a welding student preparing for a 3G test, this walks you through what the inspector expects. If you’re an apprentice moving from shop tacking into code work, it explains the “why” behind the rules your journeyman keeps repeating. If you’re a DIY fabricator stepping up from hobby projects into heavier brackets and frames — or a hobbyist troubleshooting beads that sag and trap slag — this gives you the same fundamentals taught in apprenticeship programs, without the guesswork.

If you’re still building your base before tackling vertical work, our guide to the advantages of stick welding covers why SMAW remains the go-to process for structural and field work in the first place.

What you’ll learn over the rest of this guide: how to read the E7018 classification and buy the right rod, why uphill beats downhill for this electrode, how to set up your machine and oven before striking an arc, the three physical foundations of body position and rod angle, the step-by-step root-fill-cap technique, a defect-by-defect troubleshooting table, multi-pass discipline, how 7018 compares to 6010, 6011, 6013 and 7014, and a four-to-six week practice plan to get you test-ready.

One thing up front: none of this is about talent. Vertical-up 7018 is a repeatable process — dry rod, short arc, slight push, small steps, dwell at the edges, clean every pass. Get those six things right and the puddle does most of the work for you. Let’s start decoding the rod itself.

Reading the Rod: What the E7018 Classification Actually Means

Every stick electrode carries a stamped identity, and with E7018 that code is a specification compressed into five characters, not marketing. The designation comes from the American Welding Society’s AWS A5.1 specification for low-hydrogen SMAW electrodes. Once you can decode it, you can read any rod on the rack in about three seconds — and tell the difference between a rod that will hold up in a structural joint and one that quietly sets you up for failure, especially uphill, where you have the least margin for error.

Breaking Down the Code, Digit by Digit

Character	Meaning	Why it matters uphill
E	Electrode for shielded metal arc welding (stick)	Confirms the rod is designed for SMAW holders, not GTAW filler or FCAW wire.
70	Minimum tensile strength of 70,000 psi (70 ksi) for the deposited weld metal	Matches the strength range of most structural steel, so the weld is not the weak link.
1	All-position rated: flat, horizontal, vertical and overhead	This is the digit that lets you legally run the rod uphill. A “2” would mean flat and horizontal only.
8	Low-hydrogen basic covering with an iron powder addition	Calcium carbonate (limestone) and calcium fluoride (fluorspar) form the slag system; iron powder boosts deposition efficiency per amp.
H4	Diffusible hydrogen limited to a maximum of 4 mL per 100 g of deposited weld metal	The H-designator is measured by gas chromatography. Some products are H8 or H16; the lower the number, the drier the rod.
R	Moisture-resistant, hermetically sealed foil packaging	An unopened carton can be stored without a rod oven; the clock starts when you break the seal.

Why Low Hydrogen Is the Whole Game

Hydrogen is the reason 7018 exists in its current form. Atomic hydrogen dissolves freely into molten steel, and as the puddle cools it can collect at grain boundaries or trapped sites and recombine into molecular hydrogen that builds pressure internally. In hardenable materials — high-carbon steel, high-strength low-alloy steel, thick sections under high restraint — the result is hydrogen-induced cold cracking, also called delayed cracking, which can show up hours or even days after the arc is out.

The classic recipe for cold cracking needs three ingredients together: a susceptible base metal, available hydrogen, and tensile stress. A low-hydrogen electrode attacks the middle ingredient directly. Cellulose-coated rods such as 6010 or 6013 burn hydrogen-rich by design; a basic 7018 covering produces almost none of its own. And if you are wondering why stick welding still earns its place beside MIG and flux core on heavy work, see Advantages of Stick Welding: Why SMAW Still Wins.

The catch is that basic coatings are hygroscopic. They actively pull moisture out of humid shop air, and that moisture becomes hydrogen transferred through the arc into your weld metal. A 7018 left lying on a damp bench overnight is a chemically different rod than the one that came out of the sealed carton — which is exactly why rod ovens exist and why electrode storage discipline shows up in every serious welding procedure specification.

What the Weld Metal Actually Gives You

Pinnacle Alloys reports typical as-welded E7018 results of about 82,000 psi tensile strength, 69,000 psi yield strength, 30% elongation and 52 ft-lbf Charpy impact energy at −20°F, with typical diffusible hydrogen around 2.1 mL per 100 g of deposited metal. Those numbers explain why 7018 is the default for structural work: the deposited metal comfortably exceeds the 70 ksi floor and stays tough below freezing. The iron powder in the covering also means 7018 deposits more metal per amp than a bare-cellulose rod, so fill and cap passes build faster even though the travel speed feels slow.

Amperage Ranges by Diameter

Manufacturer data sheets are consistent. The Pinnacle Alloys E7018 data sheet and Hobart Brothers’ 7018 XL sheet give these typical ranges for DCEP (AC also acceptable):

Diameter	Amperage range (flat/horizontal)	Vertical-up working point
3/32 in (2.4 mm)	70–100 A	~60–85 A
1/8 in (3.2 mm)	90–130 A	~75–110 A
5/32 in (4.0 mm)	130–200 A	110–170 A (thick fill only)
3/16 in (4.8 mm)	200–250 A	Flat and horizontal only

Both sheets carry the same critical footnote: decrease amperage by about 15% for out-of-position welding. They also note that 3/16 in and larger diameters are generally recommended for flat and horizontal positions only. For vertical-up groove work, 3/32 in and 1/8 in are your rods — small enough to control the puddle, hot enough to fuse the sidewalls. And if you want a broader look at which rods earn an all-position rating, our All Position Welding Rod Guide walks through the full lineup.

Once you know what the digits mean, the storage rules stop feeling like nagging and start making sense. A low-hydrogen rod is a system, not just a consumable: correct classification, correct diameter, dry storage, and the right amperage window for the position you are about to climb.

Why Uphill, Not Downhill: The Case for Vertical Up With 7018

On a flat plate, travel direction is mostly a matter of habit. On a vertical joint, it becomes the whole ballgame. Welding 7018 uphill means every ripple solidifies a fraction of an inch ahead of the arc and then acts as a shelf for the puddle sitting on it. The molten metal never has to hang unsupported. Run the same rod downhill and that shelf never forms: the pool races ahead of the arc, gravity drags it thin, and the slag — which melts behind the arc a beat later — gets buried under the very metal you just deposited. Direction is not a style preference here. It is the difference between a weld that fills a groove and a weld that only looks filled.

The Physics: Ripples That Carry the Next Ripple

Because 7018 is a basic, high-toughness covering, its puddle stays fluid and its slag stays liquid longer than a fast-freeze rod’s. Moving uphill, the leading edge of the pool freezes first at the top of the arc crater, so each new deposit lands on previously solidified metal. That is what produces deep penetration into the root and the heavier, cross-section-rich bead that thick plate demands. Moving downhill, the fluid pool flows ahead of the arc into metal that is still cold and unpreheated. The result is shallow, wandery penetration and a weld profile that looks acceptable on the surface but ties in poorly underneath.

ESAB’s vertical stick welding guide puts it plainly: uphill pairs with steel structures and heavy equipment, while downhill suits pipe welding and thinner materials. The same guide lists downhill’s cons as shallower penetration, weaker welds when travel speed is not perfectly controlled, and the risk of slag entrapment or undercutting. That last one is the classic beginner trap — chasing the rod down the joint, watching a shiny streak that turns out to be trapped slag when it is chipped.

What the Manufacturers Actually Specify

This is not folklore; the datasheets say it outright. The Hobart Brothers 7018 XLM datasheet lists technique notes as “Vertical – Up: Use weaving technique” and “Vertical – Down: Not recommended.” Lincoln Electric’s product pages for IRONARC 7018 MR list the welding positions as “All, except vertical down.” In other words, an electrode that is rated for flat, horizontal, vertical and overhead suddenly loses one of those four the moment you try to run it downhill. For background on why basic coatings behave this way, see Lincoln Electric’s low-hydrogen SMAW electrode overview.

Factor	Vertical Up (7018)	Vertical Down (fast-freeze rods)
Penetration	Deep, ties into root	Shallow, surface-weighted
Slag behavior	Stays behind puddle if arc is short	Tends to trap ahead of the pool
Deposition	Heavy, controlled buildup	Fast but thin layers
Typical use	Structural steel, heavy plate, pressure work, 3G/3F tests	Thin sheet, pipe roots, tack welds
Skill demand	High — puddle control and weave rhythm	High speed control, less fill capacity

Downhill still earns its keep — with the right rod. E6010 and E6011 burn fast and freeze instantly, so they can run downhill on thin sheet, root passes in pipe, and quick tacks without sagging. E6013 is the hobbyist’s downhill favorite on light gauge. The point is that those are cellulose and rutile rods designed for it. If you are still learning how rod classifications translate to real work, our All Position Welding Rod Guide walks through which electrodes genuinely earn all-position labeling. Swapping direction without swapping rod type is where most wet-bead failures start.

The Speed Trade-Off and the Skill Trade-Off

Downhill is undeniably faster per linear inch, and on a production line running thin material that speed matters. But speed is not deposition. Uphill lets you lay down a heavier weld in fewer passes, which is why codes for groove welds in heavy sections assume an uphill progression. The cost is skill: climbing a joint requires constant arc-length correction as the rod shortens, disciplined stepping, and a weave with deliberate pauses. You trade raw travel speed for control of heat input, penetration and hydrogen behavior — a trade every structural test is designed to evaluate.

So when someone asks whether 7018 can run downhill, the honest answer is: only against the manufacturer’s recommendation, only at the cost of penetration and slag control, and never on work that has to pass inspection. Uphill is not the slower way to weld with 7018. It is the way 7018 is built to be welded.

Setup Before the Arc: Machine Settings, Electrode Storage and Joint Prep

Nearly every ugly uphill bead I have seen traced back to something that went wrong before the arc was struck. Wrong polarity, a damp rod, a greasy bevel, a machine set ten amps too hot. Vertical-up 7018 is unforgiving enough on its own, so treat the setup as part of the technique rather than busywork you rush through. Five minutes of preparation saves a scrapped coupon.

Machine Settings and Polarity

Set the machine to DCEP (reverse polarity) first. It is the polarity 7018 is designed and tested for, and it gives the stable, quiet arc the basic coating is built around. Most 7018 rods run acceptably on AC too, which matters on older transformer machines or engine rigs, but check the manufacturer data sheet before you rely on it. Keep the work lead as close to the joint as practical, clamped to clean bare metal, so the return path does not force the arc to hunt.

Amperage should follow rod diameter, material thickness and position. As a starting point:

Rod diameter	Typical use	Starting amperage (out-of-position)
3/32 in	Root passes, thin plate, vertical work	60–85 A
1/8 in	Most vertical-up fill and cap work	80–110 A
5/32 in	Flat and horizontal fill only	110–150 A
3/16 in and larger	Flat fill on heavy material	150 A and up

These are working ranges, not gospel — your rod’s own datasheet wins. General practice is to drop roughly 15% off the flat optimum when welding out of position. Arc-force or “dig” should be set to a moderate level: enough to keep the arc from stuttering when the rod gets short, not so much that it blasts through a thin root. For the science behind why arc length drives voltage and heat concentration, see Lincoln Electric’s low-hydrogen SMAW overview.

Electrode Storage: The Hydrogen Battle

The basic, limestone-rich coating that makes 7018 strong is also hygroscopic — it drinks moisture out of humid shop air. Wet flux means hydrogen in the puddle, and hydrogen in high-strength steel means a real risk of delayed cracking. This is why 7018 handling is treated as a code issue, not a preference.

• Holding oven: once a package is opened, keep the rods in a rod oven controlled at 250°F to 300°F, per Pinnacle Alloys and Hobart Brothers datasheets.
• Out-of-quiver time: Michigan Tech’s welding discontinuities webinar cites typical limits of about 4 hours for standard 7018 and up to 9 hours for 7018 H4R sealed products.
• Reconditioning: if rods have been exposed too long, start at 250°F, ramp slowly, then bake at 600°F for one hour — exactly as the manufacturer instructs. Never dump cold, damp rods straight into a hot oven.

Joint Prep, Preheat and Interpass Control

Grind or cut the bevel to the profile your procedure specifies, then remove mill scale, rust, oil, paint and moisture from both faces and the backing area. Contaminants are the number-one source of porosity complaints on uphill work. Choose rod diameter honestly: 3/32 in and 1/8 in are the vertical workhorses; anything larger belongs in flat fill, where gravity helps you. Our All Position Welding Rod Guide covers how to match electrode diameter to position in more depth.

Preheat is where code compliance gets serious. An approved state DOT structural procedure specifies E7018 with a minimum preheat of 100°F for plate up to 3/4 in, rising to 225°F above 2.5 in thickness, and a maximum interpass temperature of 450°F (NCDOT approved procedures). Use a contact thermometer, not your eyes. Excessive interpass heat softens the weld zone and accelerates hydrogen loss too quickly in the wrong places; too little heat traps hydrogen and raises hardness.

Safety Setup

Before strike-off, confirm fume extraction or natural ventilation is working, welding screens are up to protect nearby workers, and your helmet, jacket, gloves and ear protection are on. OSHA’s 1926.353 sets the requirements for ventilation, shielding and PPE on welding, cutting and brazing operations. Get this wrong and the arc becomes the least of your problems.

Body Position, Rod Angle and Arc Length: The Three Foundations

Ask ten welders how to run 7018 vertical up and you will get ten answers about weave patterns. Ask why their toes stay clean and the metal stays where it was put, and the answer is always the same: a stable body, the correct rod angles, and a short arc held at a constant length. Technique built on shaky foundations just hides the problem behind a nicer-looking cap. Nail these three first and the rest falls into line almost on its own.

Stance and Bracing: You Are the Fixture

A vertical-up pass is slow. Root and fill on a 3/8 in groove joint can hold you in one spot for several minutes while the rod burns down, so your body has to stay still enough that the arc length never drifts. Start with both feet flat, about shoulder-width apart, weight balanced rather than leaning into the joint. Then brace the welding hand’s forearm on something fixed — a pipe, a fixture, a clamp. A supported forearm travels in a straight line; a floating arm sweeps an arc, and a sweeping arm quietly changes your angles without you noticing.

Height matters as much as bracing. If the joint sits above comfortable reach, your shoulder tires and your hand sags, dragging the rod angle backward exactly when the arc needs to be shortest. Before you strike an arc, run a dry pass: move the electrode up the joint at your intended travel speed and confirm you can reach the top without stretching. If you can’t, the restart forced halfway up will show in the finished bead.

Work Angle: 90° in the Groove, 45° on the Fillet

The work angle is where the rod sits side to side relative to the joint, and it barely changes as you climb. For a butt or single-V groove in the 3G position, hold the electrode roughly perpendicular to the plate at about 90°. For a 3F fillet, bisect the angle between the two members — around 45°, biased slightly toward the thicker side when the legs are unequal. ESAB’s vertical stick welding guidance gives exactly those numbers.

Hold it steady through the whole climb. Roll the rod too far one way and the arc stops digging into that sidewall; the puddle sits on top of the plate instead of tying in, and the opposite toe pays for it with a notch. Michigan Tech’s welding discontinuities training lists an incorrect work angle among the standard causes of undercut, right alongside excessive heat input and travel speed that is too fast.

Travel Angle: Flip the Push for Uphill

Here is the habit that trips up nearly everyone moving up from flat work: downhill you drag, uphill you push. In flat and horizontal the rod trails the direction of travel by 10-15°. Running 7018 vertical up, reverse it. Tilt the top of the electrode slightly ahead of the puddle, pushing about 5-10° into the direction of travel.

That small push does two jobs. It aims the arc force down and into the joint, helping penetration and sidewall tie-in, and it holds the molten pool and its blanket of liquid slag up against gravity. Drag instead and the arc points at the top of the pool; the metal and the lighter slag run out ahead, and the arc then strikes cold slag instead of steel. ESAB pairs this uphill angle with a modest amperage trim of roughly 10% below your flat setting, because the pool has less support than it doeslying down.

There is a limit to the tilt. ESAB notes that travel angles beyond about 20-25° from vertical start blowing molten metal out of the puddle, producing spatter, a starved profile and inconsistent penetration (ESAB on electrode angle control). Five to ten degrees is a nudge, not a shove.

Arc Length: Half the Core, Never More

7018 rewards a tight arc and punishes a loose one. Hobart’s 7018 datasheet calls for an arc length shorter than half the electrode diameter (Hobart Brothers 7018 datasheet). With a 1/8 in rod that means under 1/16 in — barely any daylight, just a crisp frying-bacon crackle. A long arc spreads heat, wanders, breaks the shielding envelope and hands you spatter, erratic fusion and porosity; uphill it also makes the fluid slag run, and that is the one thing you cannot afford.

Keeping it constant while the rod shortens is the real skill. Your hand has to feed toward the puddle at exactly the burn rate, which is why bracing matters: an unsupported hand tends to pull back as the electrode lightens. A moderate arc-force (dig) setting can stiffen an arc that dips momentarily short, but it does not replace a steady hand, and the reduced vertical amperage helps — a cooler rod burns slower, making that constant gap easier to maintain.

Watch the Puddle, Not the Rod Tip

Beginners stare at the arc because it is the brightest thing in the hood. The information you need lives in the puddle. First, learn to tell the two liquids apart: the duller, silvery molten steel you are depositing, and the brighter, glassier slag riding on top. Then track the toes, where every uphill problem starts. A smooth tie-in with no notch means keep going; a dark crevice opening at the edge means slow down and dwell. Cloudy and sluggish means too cold; wide and thin with the edges running means too hot or too slow.

Get the stance, the angles and the arc length on autopilot and the weave pattern becomes the easy part. For a look at how other electrodes behave out of position, our guide to the all position welding rod options covers what changes and what stays the same.

The Step-by-Step 7018 Vertical Up Technique: Root, Fill and Cap

Everything so far has been theory. This is the part where the rod either does what you want or fights you uphill. Work through it in order, because each step depends on the one before it.

1. Strike the arc and establish the root pool

Start at the very bottom of the joint. Strike the arc with a scratch or tap motion, then hold it momentarily at the root until you see a small, fluid puddle wet both sides of the joint. Resist the urge to move immediately. A root pass that starts cold never ties in properly at the bottom, and inspectors look there first.

2. Run the root as a straight stringer

The root pass goes straight up. No whipping, no stabbing, no weaving. Experienced welders on welding forums are consistent about this: the root is a stringer, and the weaving belongs to the fill and cap. A stringer root puts down a controlled, uniform bead that subsequent passes can key into, and it keeps heat concentrated where penetration matters most.

3. Build a shelf, one small step at a time

Vertical-up works because each ripple solidifies and becomes the shelf the next one stands on. Keep each upward step small — roughly a quarter of the electrode diameter or less. Lincoln’s vertical-up guidance, developed for flux-cored wire but mirrored in stick practice, stresses minimizing the upward step and never stepping up at the outer edges of the weave. Step at the center, where the shelf is thickest, and let the sides catch up as the puddle flows across.

4. Weave with deliberate hesitation at each toe

Once you move off the root, the weave begins: side to side, pausing long enough at each toe to fill the undercut zone and tie into the sidewall. TWI notes that a slight dwell at the extreme edges of a weave assists sidewall fusion and produces a flatter bead profile. Keep the weave wide enough to cover the joint, but not so wide that the pool has time to sag.

5. Mind the pause rhythm

The pause at the edges should be noticeably longer than in the middle. If you spend equal time everywhere, the center keeps depositing metal while the toes lag, and you end up with a convex, ropey bead sitting proud of the joint. Heat the edges, skim the center.

6. Keep the rod angle honest as it shortens

As the electrode burns down, your hand naturally drifts, and the travel angle steepens without you noticing. Check yourself every few seconds: the same slight push — about 5–10° toward the direction of travel — and the same short arc you started with. A steepening angle drives the arc into the joint and starts cutting the toes.

7. Tie-ins, restarts and feathering

When you stop, feather the crater by pausing briefly on the spot before breaking the arc, then chip and wire-wheel the stop completely before restarting. Start the new arc about a half-inch behind the stop, build the puddle, and blend forward. Any restart that isn’t cleaned becomes a trapped slag pocket or a cold lap on the next pass.

8. Fill and cap passes

Fill passes stack on the root until the groove sits about an eighth-inch below the plate surface. The cap is your presentation layer: slightly wider weave, same pause discipline, toes tied in, center flat. Watch the general ESAB vertical stick welding guidance on travel speed and side-to-side timing, and let the puddle, not the clock, set your pace.

9. The heat check

You are at the right amperage when the puddle stays fluid through the whole cycle, the slag peels in a continuous strip instead of clinging, and — the practical test welders pass around — the opposite side of the puddle stays cherry red during the pause instead of flashing black. Black means you paused too long or your amps are too low; a puddle that won’t hold still means you’re too hot.

Common weave patterns

• Zig-zag: even side-to-side motion, best for beginners learning the pause rhythm.
• Staircase (sawtooth): step across, move up, step back — good shelf control.
• Triangle: across the bottom, up the side, back down — favors the toes.
• Stacking: crescent-shaped ripples layered upward, common on cap passes.

Pick one, keep it consistent, and change only one variable at a time when a bead goes wrong. Consistent technique is what makes the next bead predictable — and predictability is what makes a 7018 vertical-up weld pass inspection.

Common 7018 Vertical Up Mistakes and How to Fix Them

Almost every rejected vertical-up bead traces back to a small set of repeatable errors. The useful part: each one has a visible symptom and a specific cure. Work through them defect by defect, in cause → symptom → fix order, and you will start diagnosing your own welds instead of guessing.

Undercut at the toes

Cause: too much heat, travel speed that is too fast, an arc that is too long, or an electrode angle that is too steep and blowing the arc sideways instead of into the joint. Symptom: a groove melted into the sidewall right at the edge of the bead, which the filler never fills in. Fix: slow down, tighten the arc, and dwell a beat longer at each toe. TWI notes that too-high current combined with high travel speed produces sidewall undercutting, and that the resulting notch makes slag removal difficult as well. Practical uphill troubleshooting numbers: slow your travel by roughly 15–20%, keep the electrode at a 70–80° trailing angle, hold the arc tight, and drop amperage 5–10 amps if the toes keep blowing open.

Slag inclusion

Cause: convex beads that leave crevices at the toes, skipping cleaning between passes, or undercut at the edges that traps slag in the notch. Symptom: gray or glassy slag lines buried inside the weld, usually found by visual or ultrasonic inspection rather than by looking at the cap. Fix: chip, wire-wheel and, where needed, grind between layers until the toes are bright. TWI identifies convex bead profile and incomplete slag removal as the main welder-technique causes of slag inclusions with basic E7018 electrodes. General industry guidance adds the rest of the recipe: avoid narrow, deep groove geometries, keep travel speed consistent, and remove all slag before the next run starts.

Cold lap or rollover

Cause: a pool that is too cold to wet into the sidewall, usually from insufficient amperage or a travel angle that never lets the arc reach the edge. Symptom: the bead sits on top of the plate like a rolled edge, with no tie-in at the toe. Fix: raise the amps slightly, slow the travel, push a touch more arc into the corner, and make sure the joint is free of mill scale and oil so the puddle can actually spread.

Porosity

Cause: a damp rod, or moisture, oil, paint or rust in the joint, or a draft blowing shielding gas and flux reaction products away. Symptom: pores and pinholes in the bead surface, often clustered at the start of a pass. Fix: pull the rod from the oven, grind the joint clean at least an inch either side of the weld, screen off airflow, and recheck your holding-oven discipline. A rod that has been sitting out in humid shop air can undo every other thing you did correctly.

Four more problems, quick diagnosis

Problem	What causes it	The fix
Excessive convex, “ropey” center	Pause ratio inverted, weave too narrow, amps too low	Pause longer at the toes than in the middle; widen the weave slightly; add 5–10 amps
Arc strikes and restart defects	Striking outside the joint, sloppy tie-ins	Michigan Tech calls arc strikes “100% welder error” — grind them out or re-weld
Burn-through or sagging	Too much heat for thin material, steps too long	Reduce amperage, shorten each step, feather the pause
Rod sticking	Arc started too slow, rod dragged on cold metal, amps too low	Strike with a quick scratch, keep the arc gap as the rod warms, nudge amps up

If you are still building confidence reading puddles across positions, our All Position Welding Rod Guide: Types, Uses & Tips is a useful companion piece.

The golden rule of troubleshooting: change one variable at a time. Amperage first, then travel speed, then angle, then arc length. Change two things and you will never know which one fixed it.

Multi-Pass Vertical Up: Cleaning, Interpass Control and Inspection

A pretty cap means nothing if the layers under it are contaminated. Real vertical-up 7018 work, whether a column splice, a gusset connection or a 3G test plate, is built one pass at a time, and every layer has to be treated like it will be X-rayed. This section covers V-groove sequencing, why slag removal is non-negotiable, how interpass temperature affects cracking, and what inspectors look for.

Pass Sequencing in a V-Groove

Heavy groove joints are never welded in one pass. A typical uphill V-groove runs in this order:

1. Root pass. A tight stringer establishing full penetration and fusion at the bottom of the joint.
2. Hot pass. Slightly hotter and faster, burned in to flush out remaining slag and smooth the root profile.
3. Fill passes. One or more layers building the joint to just below flush, each tied into the toes of the previous bead.
4. Cap. The visible layer, stringers or a controlled weave, finishing slightly proud of the plate surface.

Many procedures also call for a light grind of the root and any uneven fill before the next layer. Each pass should leave a shape the next one can fuse into cleanly.

Complete Slag Removal: The Non-Negotiable Rule

Basic-flux electrodes like 7018 carry a higher risk of slag entrapment in multi-pass welds, largely because of their convex bead profile and the difficulty of cleaning weld toes. TWI states plainly that it is crucial to remove all slag before depositing the next run, and that in multi-pass vertical welding with basic electrodes, care must be taken to fuse out any remaining minor slag pockets and minimize undercut at the toes.

In practice, after every single pass:

• Chip the slag with a proper chipping hammer while the bead is still warm enough to release easily.
• Wire-wheel the entire surface, paying special attention to the toe crevices where the bead meets the sidewall.
• Grind out any pocket, crevice or convex area that could shelter slag. A quick pass with a grind wheel now saves a rejected weld later.
• Check for undercut at the toes and dress it before the next layer goes over it.

If the slag does not chip off in one clean piece, that is information. Something about that bead, usually heat, angle or profile, needs correcting before you add another layer.

Preheat and Interpass Temperature Control

The low-hydrogen coating on 7018 only protects the weld if the rest of the system is dry and controlled. Hydrogen enters the puddle from a damp rod, contaminants on the joint, and humid air. Preheat and controlled cooling manage what happens to that hydrogen afterward.

Preheat slows the cooling rate, keeping hydrogen in solution longer so it can diffuse out instead of collecting at hard, sensitive spots in the heat-affected zone. Thickness drives the requirement: structural work typically demands preheat once combined thickness passes a threshold, often around 1 to 1.5 inches depending on the code and the steel’s carbon equivalent. An approved DOT E7018 fillet procedure sets a minimum preheat of 100°F for thicknesses up to 3/4 in and a maximum interpass temperature of 450°F (NCDOT). These numbers illustrate the principle, not a universal spec: always follow the WPS written for your joint.

Interpass temperature matters because overheating between passes accelerates cooling after the last pass in thick sections, raising hardness in the heat-affected zone and making hydrogen cracking more likely on higher-carbon or low-alloy steels. Check with a temperature stick or infrared thermometer, not by eye or hand. For more on the electrode side, see our guide to alloy steel welding electrodes.

How Inspection Treats the Weld

Inspection always starts with the eyes. Before any NDE, the weld is examined visually for:

• Uniform bead width and height along the entire length
• A consistent ripple pattern, which signals steady travel and arc length
• No visible undercut at the toes
• Complete root fusion, verified on open-root joints or by acceptance criteria on the finished face
• Easy slag release from every layer

When the procedure requires it, ultrasonic or radiographic testing follows, hunting for the internal defects visual inspection cannot see, primarily slag inclusions and lack of fusion. A rough visual benchmark for structural work: undercut is commonly limited to about 1/32 in (0.8 mm) deep, and a stricter WPS can tighten that.

Get the hidden layers right and the cap takes care of itself. Get them wrong and no amount of surface cosmetics will pass a competent inspection.

7018 vs 6010, 6011, 6013 and 7014: Choosing the Right Rod for Vertical Work

Here is the part of the conversation that happens in every welding lab sooner or later: a student grabs a 6013 because it arcs up so easily, tries to fill a vertical groove on half-inch plate, and fights a sagging, grey, slag-choked mess for twenty minutes. Then someone hands them a dry 7018 and the puddle finally behaves. But the reverse mistake happens too — reaching for a 7018 to tack thin sheet or run a pipe root, where a cellulose rod is the right tool all along. 7018 is the correct answer for a specific job: code-quality structural welds on heavier material. Knowing when it is not the answer is what keeps your procedure honest.

The Five Common Sticking Electrodes at a Glance

Rod	Penetration	Coating	Hydrogen	Best vertical use	Limitations
E6010	Deep, digging	Cellulose (fast-freeze)	Not low-hydrogen	Vertical up and down; pipe roots	DC only, harsh arc, rough ripples
E6011	Deep	Cellulose, AC-capable	Not low-hydrogen	Vertical on dirty, rusty, painted metal	Spattery on clean steel, DC/AC only
E6013	Shallow to moderate	Titanium-rutile	Not low-hydrogen	Thin sheet, hobby repairs, downhill	Poor on heavy vertical grooves; sags uphill
E7014	Moderate, shallow root	Rutile-iron powder	Not low-hydrogen	Fast fill and cap passes, horizontal	Not for code groove welds; thick slag
E7018	Moderate	Basic / low-hydrogen	Low (H4, H8, H16)	Vertical-up structural grooves and fillets	Needs dry storage, short arc, clean metal

ESAB’s vertical stick welding guide puts it plainly: E7018 belongs on uphill welds in structural steel and heavy-duty repair, where you need high-strength, clean weld metal in thicker sections, while E6010 covers vertical uphill and downhill and remains the classic pipe welding rod. That single assignment explains most of what you need to know. E6010 and E6011 are fast-freeze rods — their cellulose covering burns off a lot of gas, drives the arc deep, and freezes the puddle fast enough to hang overhead or run downhill. E6013 and E7014 are fill-freeze and fast-fill types: smooth, friendly, forgiving, but shallow. E7018 is a slow-freeze basic electrode — moderate penetration, a quiet arc, and a fluid slag that protects the cooling metal beautifully if you keep the arc tight.

The hydrogen side is the real dividing line. As Lincoln Electric’s overview of low-hydrogen SMAW electrodes explains, basic coatings based on limestone and fluorite can pick up moisture from ordinary shop air, and that moisture becomes diffusible hydrogen in the weld — the ingredient that causes cold cracking in high-strength and low-alloy steels. Rutile rods like 6013 and 7014 offer no such protection, which is why they are excluded from structural groove welds regardless of how pretty the cap looks.

7018, 7018-1 and 7018-A1: What the Suffix Changes

Standard E7018 suits most structural work. E7018-1 swaps in a manganese-nickel chemistry for better low-temperature toughness; Lincoln’s IRONARC 7018-1 MR datasheet reports typical Charpy V-notch results of 84–141 J at −46 °C, which is why you step up to the -1 when service temperatures drop well below freezing. E7018-A1 adds molybdenum for elevated-temperature and creep-resistant service such as boiler and pressure vessel work — a different animal entirely, and one worth researching through an alloy steel electrodes guide before you buy. For general structural welding, plain 7018 is the workhorse.

Deposition Rates and Why Diameter Matters

Rod diameter is not a casual choice on vertical work. Bigger rods deposit faster but dump more heat and metal into a joint gravity is already fighting. Pinnacle Alloys publishes deposition rates for E7018 of about 1.8 lb/h at 3/32 in (85 A), 2.6 lb/h at 1/8 in (100 A), 3.9 lb/h at 5/32 in (150 A), and 5.2 lb/h at 3/16 in (225 A). ESAB’s Atom Arc 7018 is rated under 4.0 mL/100 g diffusible hydrogen on AC or DC+, with deposition around 0.92 kg/h (2.0 lb/h) at 90% of maximum current for the 3/32 in size. Notice that the 3/16 in rod deposits nearly three times the metal of a 3/32 in — and that is exactly why 3/16 in and larger belong in flat and horizontal fill passes only. For vertical-up, stay with 3/32 in or 1/8 in, and see the All Position Welding Rod Guide for how these sizes behave across every position.

A final word on judgment calls: if the weld is going on a building column, a gusset, a bridge member or pressure components, 7018 uphill is not negotiable. If you are tacking sheet, running a pipe root, or burning through paint on a farm repair, one of the cellulose or rutile rods is genuinely the better tool. Match the rod to the service, keep the 7018 dry, and you will stop guessing at the rod rack.

Practice Plan, Safety and Final Takeaways for Mastering 7018 Vertical Up

Nothing in this guide matters until you burn rods. Vertical-up 7018 is a physical skill, and physical skills respond to structured repetition far more than to articles. The good news is that you do not need a certification lab to get better. A stack of 3/8 in plate, a box of 1/8 in 7018, and four to six honest weeks of deliberate practice will take you from inconsistent uphill beads to welds that look like a welder made them. Here is a progression that actually works.

A 4-6 Week Practice Progression

Week 1 — Dry runs and flat stringers. Before you strike a single arc, practice the motion cold. Hold the electrode in position on a scrap groove, get comfortable, and burn through the rod movement with the machine off. Focus on stance, bracing, work angle and that slight 5-10° push. Then move to flat stringers on plate, not to make pretty welds, but to learn how the puddle looks when it is happy. You are training your eyes to tell molten metal from liquid slag.

Week 2 — Vertical stringers. Run straight stringers uphill on 3/8 in plate groove coupons. No weaving yet. Learn to build the shelf in small steps, roughly a quarter rod diameter or less, and keep the arc tight. Expect failure. Keep welding.

Week 3 — Weaves. Introduce the side-to-side motion with deliberate hesitation at each toe. Start narrow and widen only when the toes are wetting in cleanly without undercut.

Week 4 — Multi-pass caps. Root, fill, cap. Chip and wire-wheel every pass without exception. Practice restarts: feather the stop, clean it, and tie back in about half an inch before the crater.

Weeks 5-6 — Mock 3G tests. Run full groove coupons under test conditions. Cut and bend them if you can, or at minimum inspect them the way an inspector would. If you want a broader structured drill set, our all position welding rod guide has useful exercises for building comfort across positions.

How to Inspect Your Own Welds

After every single bead: chip the slag, wire-wheel the surface, and look at the toes. Ask four questions.

• Undercut: Is there a groove melted into either toe? On structural work, many acceptance criteria allow no visible undercut at all, with a common tolerance around 1/32 in (0.8 mm) unless your procedure is stricter.
• Fusion: Did the weld tie into the sidewalls and the root, or is there a cold line hiding under the face?
• Profile: Flat to slightly convex is the goal. Ropey, convex centers signal a bad pause ratio or low amperage.
• Consistency: Are your ripples even and your bead width uniform? Inconsistency is almost always a body-position or arc-length problem.

Gauge the weld size, grind out anything questionable, and restart. That discipline is exactly what an inspector does for you on a real test, so learn to do it yourself first.

Safety: The Part Nobody Should Skip

Stick welding generates fumes, ultraviolet radiation and flying slag, and uphill work puts you close to the arc for long stretches. In construction, OSHA’s standard 1926.353 requires ventilation or fume removal adequate to keep exposure within limits, plus protection for nearby workers from radiation and sparks. In the shop, that translates to practical habits: run local exhaust or adequate general ventilation, use welding screens, wear a proper shade lens under your hood, a jacket and gloves, and keep dry electrodes in the holding oven rather than your pocket. Hot work near combustibles deserves a fire watch and a clear area, every time.

Five Non-Negotiables to Take to the Booth

Everything in this guide compresses into five rules. Dry rod, short arc, slight push, small steps, dwell at the edges, clean every pass. Hydrogen control is systemic, not just a rod issue: dry electrodes, clean joint surfaces, and controlled preheat and interpass temperatures all work together to reduce hydrogen-induced cracking risk in high-strength steel welds. Master those habits and the 7018 stops fighting you. It starts doing what low-hydrogen rods do best: giving you a tough, sound, code-ready weld in the position that pays the best.

Frequently Asked Questions

What amperage should I run a 7018 rod at for vertical up?

As a starting point, 1/8 in 7018 runs about 90-110 A uphill and 3/32 in about 70-90 A — roughly 10-15% below the flat optimum listed on the data sheet. Tune from there based on how the puddle behaves: sagging or wide means too hot, a stiff convex bead means too cold.

Do you push or drag a 7018 in the vertical up position?

Vertical up is the exception to the usual drag rule. Use a slight push, tilting the electrode about 5-10 degrees in the direction of travel so the arc points up into the joint and supports the pool; in flat and horizontal positions you drag normally.

Can you weld 7018 vertical down?

It is not recommended. Manufacturer datasheets list 7018 for all positions except vertical down because the basic coating’s fluid slag runs ahead of the shallow downhill pool, causing slag entrapment and poor fusion. Save downhill for fast-freeze rods like 6010 or 6013.

Why does my 7018 vertical weld have undercut at the toes?

Undercut usually comes from amperage that is too high, travel that is too fast, an arc that is too long, or an angle that is too steep. Slow down by 15-20%, tighten the arc, and dwell briefly at each edge of your weave to fill the toe before stepping up.

Why is slag so hard to remove from my vertical welds?

Basic 7018 slag freezes fast in the vertical position and sticks in convex beads and toe crevices. Weave with a slight dwell at the edges for a flatter profile, let the bead cool before chipping, and wire-wheel or grind between passes so no slag is trapped under the next run.

Do 7018 rods need to be kept dry or baked?

Yes. The basic coating absorbs moisture from the air, which puts hydrogen into the weld. Store opened rods in a 250-300°F holding oven, limit time out of the quiver, and rebake exposure rods per the data sheet (commonly around 600°F for one hour) before using them on code work.

Should I weave or use stringer beads vertical up with 7018?

Both are valid: root passes are commonly run as straight stringers, while fill and cap passes use a controlled weave with pauses at the edges. High-responsibility welds often require stringers only, and weave width is commonly limited to about 2.5-3 times the rod diameter — always follow your WPS.

What size 7018 rod is best for vertical welding?

3/32 in and 1/8 in are the practical vertical choices because they keep heat input and puddle size manageable against gravity. Move to 5/32 in only if you have the amperage and joint width to control the pool, and reserve 3/16 in and larger rods for flat and horizontal fill.

Why do I keep sticking the rod when starting uphill?

Usually it is a combination of too-low amperage, too long a striking distance and an awkward body position. Brace your hand, use a light scratch start, and set the machine at the higher end of the range you are comfortable with — a 7018 that is too cold is far more likely to stick.

Is 7018 stronger than 6013 for structural vertical welds?

E7018 requires 70,000 psi tensile strength and is low-hydrogen, which code work on structural steel demands; E6013 is a rutile, easier-running rod with lower strength and higher hydrogen risk. For certified or load-bearing vertical joints, 7018 uphill is the standard choice.