3G Test Welding: What It Is, Requirements, How to Pass

A welder walks into a structural fabrication shop for a job interview, and the very first question from the foreman is not about experience or references — it is a blunt, “Are you 3G certified?” In that moment, everything depends on a single vertical plate test most applicants underestimated. Understanding what the 3G test welding actually involves — the setup, the technique, and the inspection — is the difference between walking out with a work order and walking out empty-handed.

What Is a 3G Weld Test? A Real-World Introduction

A welder walks into a structural fabrication shop for a job interview, and the first question from the foreman isn’t about experience or references. It’s blunt: “Are you 3G certified?” In that moment, everything depends on a single vertical plate test most applicants underestimated. Understanding what the 3G test welding actually involves — the setup, the technique, and the inspection — is the difference between walking out with a work order and walking out empty-handed.

So let’s answer the principal question right away. The 3G test is a welder performance qualification test performed on a plate coupon oriented vertically and welded in the vertical groove position, almost always with uphill progression. The “3” refers to the vertical position, and the “G” stands for groove. You bevel two plates, clamp them upright, and run a groove weld from bottom to top under a supervisor’s watch. Then the coupon gets inspected, and usually cut up and bent to prove the weld is fused clear through.

Plain Language: What Actually Happens

Physically, the test is unglamorous. A 3/8-inch A36 steel plate assembly with a single-V groove and a backing bar is clamped vertically at 90 degrees to the floor. You weld it uphill per a written procedure. As the American Welding Society defines it, welder performance qualification is the demonstration of a welder’s ability to produce welds meeting prescribed standards, and welder certification is the written certification that the welder has produced welds meeting that standard (AWS Welding Digest). In other words, the coupon is the demonstration, and the paperwork that follows is the certification.

That paperwork matters. Passing a code-based 3G test produces a Welding Performance Qualification Record (WPQR) — a written verification that serves as the welder’s code-based certification under AWS D1.1. It is not a magic “license” that lets you weld anything, anywhere, forever. It is a record, held by an employer or issued through an accredited test facility, that says: this welder passed this test to this procedure in these positions.

Welder Qualification vs. Procedure Qualification

These two get confused constantly, so it’s worth separating them early.

• WPS (Welding Procedure Specification) — the recipe: process, filler, current, position, preheat, travel speed limits. Written and proven by a PQR (Procedure Qualification Record).
• WPQR (Welder Performance Qualification Record) — the proof that a specific human can follow that recipe and produce an acceptable weld.

The procedure is qualified first; the welder is qualified against it. When a foreman asks “Are you 3G certified?”, what they really need to know is whether you can produce sound vertical groove welds to their qualified procedure — and whether there’s documentation to back it up.

Why Employers Ask for It

Vertical groove welds are where structural money is made and where defects hide. A bridge girder, a column splice, a heavy equipment frame — most of the critical joint length in a steel structure sits in the 3G position. Structural fabrication shops, bridge contractors, and union training programs commonly require a passed 3G before assigning vertical groove work, because the code requires it and because vertical is unforgiving: gravity works against your puddle the entire time.

There’s also a practical hiring reason. An employer-run “performance test” — the kind where a shop hands you a plate and watches you weld with no code behind it — generally does not transfer to other employers the way a code-based qualification does. A WPQR written against AWS D1.1 travels with your documented welding ability; a shop’s informal pass mostly proves you survived their shop that day.

Who Takes the 3G Test

The audience for this test is wide:

• Structural fabricators needing certified plate welders for buildings and platforms.
• Bridge and ironworker contractors where field and shop groove welds dominate.
• Shipyards qualifying welders on vertically oriented plate assemblies.
• Union apprentices and welding students using the test as a career entry gate.
• Career changers converting from another trade into a documented welding credential.

Standards programs make the record portable and verifiable. AWS operates Accredited Test Facilities and the National Registry of Certified Welders under AWS QC47, so a qualification earned at an accredited facility can be looked up and confirmed by a future employer rather than taken on faith.

What This Article Covers

From here, we’ll decode the “3G” label and exactly which positions it qualifies, walk through the governing codes (D1.1, B2.1, ASME Section IX), break down coupon setup, compare SMAW, GMAW, and FCAW versions of the test, dig into the vertical-up hand skills that actually decide your result, and finish with inspection criteria, common failure causes, and what to do after you pass. By the end, you’ll know exactly what happens on test day — and what the person evaluating you is looking for before you ever strike an arc.

Understanding the “3G” Label: Welding Positions Explained

If you have spent any time around a fabrication shop, you have heard the shorthand: “He’s a 3G man,” “We need a 4G hand,” “Are you 6G certified?” Nine times out of ten, nobody stops to explain what those two characters actually mean. Yet that two-character code decides which welds you are legally allowed to run, which jobs you can be assigned, and which test you should be paying for.

Here is the good news: once you decode the label, the whole system makes sense in about five minutes.

The Number Is the Position, the Letter Is the Joint

American Welding Society position codes are built from two parts. The number describes where the weld sits relative to the welder, and the letter describes the kind of joint.

For plate work, the numbers run 1 through 4:

Number	Plate position	Plain description
1	Flat	Welding down into the joint from above; gravity works for you.
2	Horizontal	The joint runs horizontally at roughly waist height, weld beads stack sideways.
3	Vertical	The joint runs up and down; you weld against gravity.
4	Overhead	The joint is above your head and the puddle hangs underneath it.

The letter tells you the joint geometry: G means groove (the weld sits inside a prepared edge or bevel), and F means fillet (a lap or T-joint where two surfaces meet at an angle). So “3G” is simply: groove weld, vertical position. “2F” is a fillet weld in the horizontal position. Nothing more exotic than that.

What Passing a 3G Test Actually Buys You

This is where most applicants get confused, because a single test quietly qualifies you for far more than the coupon you welded. Under AWS welder performance qualification rules, qualification runs in ranges rather than single positions. Per AWS D1.1 Tables 6.10 and 6.11, a welder who passes a plate groove test in 3G is qualified for:

• Groove welds: 1G (flat), 2G (horizontal), and 3G (vertical)
• Fillet welds: 1F, 2F, and 3F

Think of it as the difficulty ladder: vertical is treated as the harder skill, so proving you can control a puddle climbing uphill automatically proves you can control one running downhill in flat and horizontal. Qualifying in a more difficult position carries you downward within the same weld type.

What it does not buy you is overhead. A standalone 3G qualification excludes 4G groove and 4F fillet work entirely. Overhead is a different animal: the puddle sags, travel speed tightens up, and the bead profile has to stay narrow enough that surface tension holds it in place. D1.1 does not assume that skill from a vertical test.

The Counterintuitive Part: 4G Does Not Qualify Vertical

Here is the fact that trips up even experienced welders. Passing a 4G test qualifies you for groove welds in 1G, 2G, and 4G, plus fillets in 1F, 2F, and 4F — but not 3G or 3F. Vertical is treated as its own distinct skill set, and overhead qualification does not reach down into it, as plate qualification guides spell out.

The practical consequence: the standard route to full all-position structural coverage on plate is the 3G + 4G combined test, which is exactly what state DOTs and structural fabricators request when they ask for “all-position.” The NCDOT 3G/4G plate certification package is a typical example of how agencies frame it: two coupons, four position qualifications total — 1G, 2G, 3G, 4G groove and 1F through 4F fillet.

Test taken	Groove positions earned	Fillet positions earned
3G only	1G, 2G, 3G	1F, 2F, 3F
4G only	1G, 2G, 4G	1F, 2F, 4F
3G + 4G	1G, 2G, 3G, 4G (all-position)	1F, 2F, 3F, 4F

Plate 3G Is Not Pipe: Meet 2G, 5G, and 6G

Tubular qualification uses its own numbering, and confusing the two is a fast way to show up for a job you are not qualified to hold. On pipe, 2G means a horizontal pipe with a vertical weld axis, 5G means a fixed horizontal pipe welded in vertical uphill and downhill positions, and 6G means a fixed pipe inclined at 45 degrees, the toughest common field test. All of the 6G positions must be welded without rotating the pipe.

Because a plate 3G coupon is flat plate clamped vertically, it demonstrates none of the out-of-position puddle control required around a circumference. A plate 3G credential therefore does not qualify you for pipe work; you need a tubular test of the type your employer’s WPS calls for. If your goal is structural steel, bridges, and buildings, 3G (ideally 3G + 4G) is the right target. If your goal is pipeline or process piping, start researching 6G instead, as 3G test walkthrough guides consistently advise.

What This Means for Your Test Plan

Before you book a slot, find out which positions the shop actually runs. A shop that runs overhead on column flanges will not care that you are a solid vertical welder. Most entry-level structural openings want 3G at minimum, many want 3G/4G, and the pipe-side trades want something else entirely. Match the coupon to the work, confirm the governing standard with your employer or test facility, and only then strike the arc.

Codes, Standards, and Rules Behind the 3G Test

Two welders can run identical coupons in two different shops and still be “qualified” under two completely different rulebooks. That happens because a 3G test is never just a test — it is a test performed under a specific standard, to a specific procedure, documented in a specific way. Before you strike an arc on test day, you should know exactly which document governs your coupon and what that document demands.

The Standards You Will Run Into

AWS D1.1/D1.1M:2025 — Structural Welding Code—Steel. This is the dominant standard for structural plate qualification in the United States. If the shop builds buildings, bridges, heavy equipment frames, or general structural steel, D1.1 is almost certainly the contract code. One critical detail catches people out: clause numbers and table references shift between editions. A test plan written against D1.1:2015 may cite different clause numbers than the 2020, 2021, or D1.1/D1.1M:2025 edition. Always confirm which edition the employer or contract requires before you memorize anything, because acceptance criteria that were fine under one edition can be misquoted under another.

AWS B2.1/B2.1M — Specification for Welding Procedure and Performance Qualification. When no governing code is specified by contract or regulation, B2.1 steps in as the fallback. It supplies the test method and acceptance criteria used under the AWS certified welder program, so a test facility running an AWS-registered performance qualification without a project-specific code will typically reach for B2.1.

AWS QC47 — Standard for AWS Accredited Test Facilities. QC47 is what makes a testing facility an AWS Accredited Test Facility in the first place. It governs how those facilities run welder testing, how they certify and list welders, and how qualified welders get entered into the AWS National Registry of Certified Welders (NRCW). The current published version is available as QC47-2016 with Amendment 3. If your test is taken at an accredited facility rather than in-house, QC47 is the standard behind the scenes.

ASME Boiler and Pressure Vessel Code, Section IX. This is the pressure-vessel and piping counterpart, and it runs its own system with its own position ranges, thickness ranges, and essential variables. Here is the part that surprises people: a D1.1 3G plate coupon does not automatically satisfy ASME IX requirements. The position ranges and coupon geometry differ, so welding pressure work usually means taking a separate qualification, or confirming that the employer’s Section IX procedure genuinely covers your test.

AWS A3.0 — Standard Welding Terms and Definitions. A3.0 is the dictionary behind all of it. Every time a code says “performance qualification” or “continuity,” A3.0 fixes the meaning of that word so arguments in the shop get settled by the standard rather than by opinion.

WPS, PQR, and WPQR: Three Documents That Get Confused

These three acronyms are the source of endless mix-ups, so it pays to be precise:

• WPS (Welding Procedure Specification) — describes how to weld: process, filler class, polarity, heat input range, positions, preheat, and pass sequence. This is the recipe.
• PQR (Procedure Qualification Record) — the test data proving that the recipe actually produces sound metal: variables used, test results, and lab reports. This is the proof the recipe works.
• WPQR/WPQ (Welder Performance Qualification Record) — the record proving that an individual welder welded a coupon acceptably to a given WPS. This is the document an employer keeps on you.

Essential variables tie all three together. If your test changes process, welding position, material thickness range, filler metal classification, current type, or progression direction beyond what the qualified WPS allows, the qualification is no longer valid and requalification is required.

Continuity: The Rule That Quietly Expires Your Qualification

Under AWS welder programs, continuity of the welding process must be maintained and documented, typically on a six-month cycle, verified by a wallet card or a signed continuity record. Miss that documentation window and your qualified status lapses — even if your skill never slipped. Retests after a lapse follow the governing standard’s rules, so keep copies of continuity records for every job you hold.

AWS Certified Welder Card vs. Employer-Held WPQR

The two are often treated as interchangeable, but they are not. An employer-held WPQR is your performance qualification to a specific WPS at that company. The AWS Certified Welder credential, earned through an accredited test facility, is a portable, registry-listed record of the same kind of performance test — but employers may still require their own qualification once you are on the payroll. Knowing which one the foreman actually means saves you a wasted test fee and an awkward conversation.

Test Coupon Setup: Plate Prep, Fit-Up, and WPS Variables

Most welders cram for a 3G test by practicing weaves and skipping the setup table. That is backwards. By the time the arc strikes, the result is already half decided. A clean, square, properly gapped coupon behaves like it wants to be welded. A sloppy one — open root, backing bar with a gap under it, mill scale clinging to the bevel — fights you from the first root pass to the last cap ripple, and no hand skill quietly fixes bad fit-up.

Everything below comes from the qualified welding procedure specification (WPS) the test is run to, rather than from memory or whatever your last shop happened to do. Read the paperwork first, then fit the coupon to match.

The Plate Itself: Material and Thickness

The standard structural 3G coupon is ASTM A36 carbon steel, the same grade you meet in beam, column, and base-plate work. The most frequent test thickness is 3/8 in (about 10 mm). Some facilities also run a 1 in thick coupon for unlimited-thickness qualification on heavy structural work.

Thickness matters because the coupon you burn limits what you can weld later. Under AWS D1.1 practice, a 3/8 in test plate typically qualifies you for production groove welds up to 3/4 in thick, while a 1 in test plate removes the thickness ceiling entirely.

Test coupon thickness	Typical production coverage
3/8 in (10 mm)	Groove welds up to 3/4 in
1 in (25 mm)	Unlimited thickness, groove welds

Material traceability is not optional. AWS QC47, which governs AWS Accredited Test Facilities, requires test material traceable to its specification and the coupon identified before welding begins — typically stamped or tagged on the backing bar or plate edge, never on the face you will weld. QC47 also requires specimens kept at the facility for at least 30 days, so an inspector or employer can verify what was tested.

Groove Geometry: Bevel, Root Face, and Root Opening

The joint is a single-V groove beveled at 22.5 degrees per side for a 45-degree included angle. The root face is cut to a knife edge — nearly zero land — which makes full penetration easier and lets you watch the keyhole open on the root pass.

The root opening is commonly 1/4 in, set with spacers rather than eyeballed. The spacers come out before welding; the gap you set is the gap you weld. The backing bar, usually 1/4 in thick (some procedures allow up to 3/8 in), sits tight against the back of the joint with full contact along its entire length — no daylight, no high side, no warped bar. Tacks go on the back side so they never contaminate the groove or get judged as part of the weld.

Cleaning: The One-Inch Rule

Rust, mill scale, oil, grease, and moisture are the silent killers of bend tests. All must be removed from at least one inch on each side of the joint before fit-up, with a grinder, wire wheel, or solvent rag. Damp plate near a root pass is a direct path to porosity and hydrogen trouble. Slag and oxide also have to be cleaned between every pass on the root and hot passes — the detail that separates welders who sail through bends from those who fail on one trapped slag line.

Preheat and Interpass: A Real-World Example

Temperature limits live on the WPS and vary by base metal, thickness, and code. A useful reference point is the NCDOT bridge 3G/4G procedure for structural steel: E7018 filler per AWS A5.1, DCEP polarity, vertical-up progression, a 50°F minimum preheat, and a 450°F maximum interpass temperature on 3/8 in A36 plate. In a cold shop that preheat is a quick propane pass and a temperature stick reading, not a guess. The 450°F ceiling is equally real: overheat the interpass and the heat-affected zone grows, the bead flattens and washes out, and you have handed yourself undercut for free.

Why the WPS Overrides Everything You Remember

As AWS explains in its welder performance qualification guidance, the welder qualifies to a procedure, not to a position in the abstract. The essential variables on that WPS must match what you weld in production: process (SMAW, GMAW, FCAW), position, thickness range, electrode or wire class, current type and polarity, and direction of progression. Run a vertical-up test when the WPS calls for vertical-down and you have technically welded outside the procedure, even if the bead looks beautiful.

Test-Day Setup Checklist

1. Confirm the WPS is current and covers 3G vertical groove for your process and thickness.
2. Verify the plate is A36 and traceably identified; confirm your coupon is stamped or tagged.
3. Match plate thickness to your required range (3/8 in or 1 in).
4. Grind both bevels to 22.5° per side with a knife-edge root face.
5. Clean one inch on each side of the joint.
6. Set the backing bar in full contact and tack it from the back.
7. Set the 1/4 in root opening with spacers, then remove them.
8. Clamp the assembly vertical, 90° to the floor at chest-to-shoulder height.
9. Check preheat and watch interpass temperature with a temp stick or IR thermometer.
10. Grind tack ends and clean the groove once more before striking the arc.

Get that list right and the welding gets noticeably easier. Failures start at the setup table, long before the test plate ever sees an electrode — not at the weave.

The 3G Test by Process: SMAW, GMAW, and FCAW

The 3G position never changes. The plate is still vertical, the groove is still a single-V, and the acceptance criteria are still the same. What changes is how each process behaves when you point it uphill and ask it to fight gravity. A puddle that sits calmly in flat position will sag, wander, and trap slag the moment you rotate it vertical. That is why the process you test in matters as much as the position itself.

SMAW 3G: The Stick Test Most Shops Still Ask For

Shielded metal arc welding remains the most common route to a 3G qualification, largely because structural shops still run more stick than anything else on field jobs. A typical stick 3G coupon for 3/8 in plate follows a well-worn pattern: an E6010 root pass welded vertical-up with a tight arc and a whip-and-pause motion, followed by E7018 fill and cap passes run short and stringered or gently woven.

On the root, the whole game is the keyhole. You watch that small opening ahead of the puddle and time each forward step so the arc punches through and fuses both toes before you step back to let the puddle catch up. Push too far and you blow the root open; hesitate too long and the keyhole closes and you lose penetration. The root runs on DCEN per most WPSs, while the E7018 cover passes run DCEP with a noticeably shorter arc and almost no side-to-side wander.

Plan on roughly four to five passes total for a 3/8 in coupon: one root, two or three fill passes, and a single cap. Each layer has to be brushed and chipped clean before the next one goes down, because a 7018 bead laid over 6010 slag will not save you at bend time.

GMAW 3G: Short-Circuit and Spray Vertical-Up

GMAW, what most welders call MIG, qualifies under the same position table but behaves very differently uphill. The transfer mode written on the WPS decides everything: short-circuit transfer (GMAW-S) runs cooler and is forgiving on thin plate, while spray transfer gives deeper penetration and a smoother bead but needs more heat control vertical-up. Both are legal for a 3G test, provided the settings, gas mixture, and wire classification match the procedure.

Vertical-up GMAW means dialing back from your flat settings. Wire feed speed and voltage come down, travel slows, and the arc stays tight against the leading edge of the puddle so the deposited metal sits on a shelf of previously solidified beads rather than running downhill. The standard weave pattern is a small U or zigzag with a deliberate pause at each toe.

One rule catches people out repeatedly: under AWS D1.1 requirements for 3G/4G plate qualification, radiographic testing may substitute for bend tests on most groove welder tests, but not for GMAW short-circuit transfer. A GMAW-S coupon must be bend tested. If your shop plans to use RT instead of destruction, that alone may steer you toward stick or FCAW for the test.

FCAW 3G: Flux-Cored, Vertical-Up

Flux-cored arc welding is the workhorse of structural and heavy fabrication, and its 3G test is unforgiving in one specific way: slag. A typical setup uses an E71T-1 style self-shielded or gas-shielded wire at 0.045 in diameter, with a contact tip to work distance of about 1/2 to 3/4 in. Longer stickout than that and your amperage drops enough to cause cold lap.

Instructors consistently recommend pulling wire feed speed and voltage down roughly 10–20% from your flat settings before you strike an arc uphill, then adjusting in small increments. Travel speed on the root runs around 4–7 ipm, speeding up on the cap as the puddle gets less support from the joint geometry. Slag removal here is aggressive and constant: every pass gets wire-brushed or chipped before the next one, because FCAW slag trapped under a fill pass shows up as a lack-of-fusion indication on the root bend.

Process Comparison at a Glance

Factor	SMAW	GMAW	FCAW
Typical filler	E6010 root / E7018 cap	ER70S-6 solid wire	E71T-1 flux-cored
Vertical-up key skill	Keyhole control, whip-and-pause	Heat reduction, tight arc	Stickout and settings control
Slag burden	Moderate (chips easily)	None	Heavy (must clean every pass)
RT in lieu of bends	Allowed per WPS	Allowed for spray, not for GMAW-S	Allowed per WPS
Typical passes (3/8 in)	4–5	4–5	4–5
Best for	Field and structural shops	Production and thin material	Heavy structural, bridge work

Which Process Should You Test In?

One practical rule overrides every other consideration: test in the process your employer actually runs. A qualification is only useful against procedures the shop is qualified to use, and each process’s essential variables, including transfer mode, filler classification, and shielding gas, must match the WPS that will be used for the qualification test. Walking in with a GMAW certificate when the shop welds 7018 all day does you no good.

If you are a career changer with no shop lined up yet, SMAW gives you the widest initial usefulness for structural and field work, FCAW is the close second for heavy fabrication, and GMAW shines in production environments. Many welders ultimately hold more than one. As qualification guides for the 3G stick test, 3G MIG vertical-up, and 3G vertical flux-cored welding all note, the fundamentals transfer between processes, but the settings, travel speeds, and cleanup habits do not.

Whatever you pick, run a few practice coupons in that exact process at the exact thickness before test day. The position does not care which gun or stinger you are holding, but your muscle memory certainly does.

Vertical-Up Technique: The Skill That Decides the Test

For most welders, the moment that separates a passed coupon from a failed one comes when the electrode or gun has to climb. The 3G test takes everything learned in the flat and horizontal positions and flips gravity against the puddle. Instead of letting the molten metal lay back into a natural bead, the vertical-up welder must hold it in place, inch by inch, on a constantly forming shelf of solidified metal. Mastering these hand skills is often the single largest factor in passing, regardless of how well a welder performs in 1G or 2G.

Angles, Arc Length, and Puddle Control

The foundation of vertical-up welding starts with proper body and gun positioning. A widely accepted principle across structural codes, including the guidance found in welding qualification and certification resources, is to keep the electrode or gun nearly perpendicular to the joint, tilted just 5–15° in the direction of travel. This slight upward push helps direct the arc force into the leading edge of the puddle while counteracting gravity’s pull on the molten pool. Holding too steep of a travel angle will force the puddle to wash ahead and sag, while dragging it backward will starve the fusion zone.

Equally important is keeping a short arc length. Excessive arc length exposes the molten metal to air, increasing spatter, porosity, and heat loss. A tight arc keeps the puddle compact, allows better visibility of the toes, and concentrates heat where fusion is needed. The real trick, however, is reading the puddle. A properly controlled vertical-up puddle should appear like a small, bright “keyhole” or crescent that is constantly being chased up the joint. If it grows wide and glassy, heat is too high. If it looks tight, harsh, and struggles to wet the sides, it is usually time to bump the heat up slightly.

Weave Patterns, Pausing, and Building a Shelf

Unlike flat welding where large, continuous beads are common, vertical-up rewards patience. Stringers are the safest starting point for beginners, as they concentrate heat and limit width. From there, controlled weaves become necessary to fill wider grooves. The most common patterns are the triangle, J, and chevron weaves. Each of these allows the welder to briefly pause at the toes to allow for proper fusion without undercutting. This toe-pause is one of the most repeated pieces of advice from training resources, and it is echoed in process-specific guides for SMAW vertical certification and MIG vertical-up testing.

When using any weave, the key is to avoid letting the center of the bead freeze before the arc returns. Wagon-track valleys are a direct result of weaving too wide, leaving a low, unfilled groove along the middle of a pass that the next layer will struggle to cover. By building each pass on a shelf of solidified metal from the previous one, the welder creates a platform that catches the molten puddle, preventing it from sagging down the plate. This “step up the ladder” approach is what makes multi-pass groove welds feasible in 3G.

Interpass cleaning cannot be skipped. Chipping, scraping, and wire-brushing between passes until the toes and tie-ins shine removes slag, oxidation, and potential slag traps. For FCAW in particular, vertical flux-cored arc welding practice heavily emphasizes aggressive cleaning, as trapped slag is one of the most common culprits revealed during root and face bend testing.

Practice Drills and Defect Prevention

The fastest way to develop feel is through repetition on scrap, not guesswork. Instructors recommend practicing 4–6 inch vertical beads on scrap plate clamped at chest height. Starting from a reasonable test-range setting, adjust current in 5-amp increments until the puddle wets in cleanly without excessive sag. This small-step adjustment allows the welder to dial in for their machine, rod, wire, and position. Many training programs align this methodology with the practical expectations found in plate qualification training material.

To help troubleshoot on the fly, use the table below to spot and correct the defects that most often cost welders their 3G coupons:

Defect	Likely Cause	Quick Fix
Undercut	Rushing toes, long arc, or excessive travel speed	Pause ~½ second at each toe, tighten arc, and reduce travel speed slightly.
Wagon tracks	Weaving too wide; center freezes before returning arc	Narrow weave, use stringers, or return to the center sooner.
Cold lap	Insufficient heat at toe, no pause, or dragging puddle	Add heat in 5-amp steps, pause at toes, and push into the leading edge.
Sagging/convex beads	Excessive heat, slow travel, or poor shelf	Reduce amps slightly, increase travel speed, or build on previous solid shelf.
Slag inclusions	Poor interpass cleaning, tight crevices, or trapped flux	Chip/wire-brush until toes and tie-ins shine before next pass.

These corrections are not theoretical. They reflect the workmanship expectations outlined in performance qualification guidance from sources such as the AWS Welding Digest on welder performance qualification, which stresses that consistent fusion, clean tie-ins, and proper pass sequencing are what inspectors look for above flashy technique.

In the end, vertical-up mastery comes down to discipline over speed. By holding your angles steady, chasing the leading edge, pausing at the toes, cleaning religiously, and dialing in heat with small 5-amp adjustments, the vertical climb becomes methodical rather than a race against gravity. That consistency is exactly what allows a welder to walk off the test stand with a solid coupon, ready for inspection.

Inspection and Testing: Visual, Bend Tests, and Acceptance Criteria

Passing the 3G test is not a matter of a supervisor nodding at your finished bead. The coupon you weld goes through a fixed evaluation sequence, and the order matters: visual inspection comes first, and it is a gate. Under AWS welder performance qualification practice, the coupon must pass visual inspection in the as-welded, ungrouded condition before a single bend specimen is cut. Fail visual, and no mechanical testing proceeds at all — there is nothing to bend.

Step 1: Visual Inspection by a Certified Welding Inspector

A Certified Welding Inspector (CWI) examines the as-welded coupon before any grinding, cutting, or backing bar removal. This is deliberate: grinding can hide undercut and fusion defects, so the code wants to see the weld exactly as you left it. AWS QC47 requires coupons to be inspected in the unground condition, with power tools permitted only for feathering tacks.

The commonly cited visual acceptance limits for a structural groove weld are straightforward:

• No cracks of any kind, anywhere.
• No incomplete fusion or lack of penetration.
• Undercut no deeper than 1/32 in (0.8 mm).
• No arc strikes outside the weld zone — including on the backing bar face and surrounding base metal.
• No overlap, no porosity open to the surface beyond the limits your WPS and the governing code allow.

Check those limits against your project’s governing standard; some agency specifications are stricter than the base code. State DOT projects, for example, publish their own approved procedures and acceptance criteria (see NCDOT’s 3G/4G plate certification procedures).

Step 2: Cutting the Bend Specimens

Once the coupon passes visual, it gets cut into bend specimens. A typical 3/8 in plate CJP groove test yields four specimens: two face bends and two root bends. The backing bar is removed, saw-cut edges are ground smooth, and the specimen corners are radiused to the dimensions shown in the D1.1 figure — corner preparation matters, because a sharp corner creates a stress riser that can crack during bending and falsely fail your weld.

Step 3: The 180° Guided Bend

Each specimen is bent 180° around a mandrel in a code-compliant guided bend jig. After the bend, you evaluate the convex surface — the side that was in tension and stretched open. Any lack of fusion, slag pocket, or crack that was hidden inside the weld now shows up as an opening in the stretched surface.

Evaluation	Acceptance limit
Open discontinuity (any direction, convex surface)	No single indication > 1/8 in
Multiple smaller indications (> 1/32 in each)	Combined length ≤ 3/8 in
Corner cracks	≤ 1/4 in tolerated only if clean; if they trace to slag or fusion-type discontinuities, the 1/8 in limit applies
Oversized clean corner cracks	May be disregarded and a replacement specimen tested
Visual: undercut	≤ 1/32 in deep
Visual: cracks, incomplete fusion, arc strikes outside weld zone	Not permitted

The corner-crack rule trips people up. A brittle corner that snaps off cleanly during the bend is a specimen artifact, not evidence about your weld — but if the crack follows a slag line or an unfused toe, it counts against you at the full 1/8 in limit.

RT Substitution and Specimen Retention

Radiographic testing can substitute for bend tests in some cases under D1.1, but there are hard limits: for example, GMAW in short-circuit transfer mode cannot use RT in lieu of bend tests, because short-circuit arc characteristics can hide lack of fusion from the film. When RT is used, QC47 requires 30-day retention of coupons and film so the results remain auditable.

How to Read Your Results

You will usually get one of three outcomes. Full pass: visual accepted, all four bends accepted, and a WPQR is issued. Conditional or partial: one specimen fails while others pass — the governing standard decides whether a retest of a replacement specimen is allowed, and repeated failures can restrict your qualification. Fail: the coupon fails visual, and the test stops there. Retests follow the governing standard’s rules, which typically require re-prepping a new full coupon rather than re-bending a scrap piece.

For a closer look at how these evaluations run in practice, GoWelding’s 3G SMAW walkthrough and WeldCertTest’s plate qualification guide both detail the specimen counts and bend jig setup.

The practical takeaway is simple: half the battle is won before the bend jig. Weld like a CWI is watching every pass — because after the fact, the only things that matter are what the inspector can see in the ungrouded weld and what the tension surface reveals at 180 degrees.

Why Welders Fail the 3G Test — and How to Fix It

Most welders who fail the 3G test don’t fail because they can’t hold an arc. They fail because of one root-pass defect they couldn’t see, a rushed toe that left undercut, or an arc strike on clean plate six inches from the joint. The coupon goes to a Certified Welding Inspector first and a bend jig second, and both are hunting the same handful of mistakes. Knowing the common failure modes before test day is the cheapest insurance you can buy.

Root Bend Failures: Where Most 3G Tests Are Lost

The majority of 3G failures happen on the root bend specimens. A typical 3/8 in coupon gets cut into four strips, usually two face bends and two root bends, then folded 180° around a plunger in a code-compliant jig. On a root bend, the root pass ends up on the convex, stretched side, so any lack of fusion or trapped slag in that first pass opens up into a visible crack or separation.

This is why experienced instructors obsess over the root. With SMAW, the E6010 root is run watching the keyhole: if it closes, you’re moving too slow or running too hot; if it never forms, you’re too cold or too fast. As the 3G SMAW certification guide emphasizes, consistent penetration and a clean tie-in to the backing bar matter far more than a pretty cap. And between passes, trapped flux or electrode slag at the toes and tie-ins is the single most common defect on the whole coupon. Aggressive chipping and wire-brushing before every subsequent pass is what prevents it.

Undercut, Porosity, and Arc Strikes

• Undercut almost always comes from rushing the toes of a weave. The fix: pause at each side long enough for the puddle to wash in and fill the groove the arc left behind, and keep your arc length tight.
• Porosity traces back to shielding loss, which means drafts from shop doors, gas flow set too high or too low, or leaky liners and hoses, or to contaminated base metal. Mill scale, rust, oil, and moisture must be removed within about an inch of the joint before the first arc.
• Arc strikes on the base metal outside the weld zone are treated as an automatic rejection under AWS D1.1 visual acceptance criteria, and they are painfully common when welders rest a rod end or flick an arc on the plate face. Prevention costs nothing; grinding them out afterward doesn’t undo the inspection.

Under state DOT 3G/4G plate certification procedures, the visual inspection happens before any destructive testing. Fail visual and the bend specimens never get cut.

Wagon Tracks, Cold Starts, and Crater Cracks

Overwide weaves are a beginner’s signature and a reliable defect generator. The center of the puddle outruns the edges, producing sagging, convex beads, and the classic “wagon tracks” — a valley of trapped slag running down the middle of each pass. Narrower stringers give you far more control and reduce slag trapping; if you do weave, hold it to roughly 2.5 times the electrode diameter.

Cold starts show up as lack of fusion at the beginning of a pass, and crater cracks show up at the end. Restart slightly uphill from the previous stop, tie into the existing crater, and fill the final crater by backtracking before you break the arc.

Symptom → Cause → Fix

Symptom	Likely Cause	Fix
Root bend opens with a visible crack	Lack of fusion or trapped slag in the root pass	Watch the keyhole, hold a tight arc, chip and brush thoroughly between passes
Undercut at weave toes	Too fast, no pause at the sides	Pause at each toe; keep the weave narrow
Porosity in the weld face	Shielding loss or dirty plate	Check gas flow, hoses, and drafts; clean mill scale, rust, oil, and moisture within 1 in of the joint
Arc strikes on the plate	Rod resting, careless arc starts	Strike arc only in the joint; clip rod ends; use a scratch plate
Wagon tracks down the pass center	Overwide weave, slag not cleared	Switch to stringers or a narrow weave; chip aggressively
Crater crack at pass end	Arc broken too quickly	Backtrack and fill the crater
Cold-start lack of fusion	Restart too cold or too far uphill	Restart slightly uphill; hold longer at the tie-in

Workmanship Discipline: The Test Is Watched

Here’s the part career changers underestimate: the test is run to a WPS and observed start to finish by a supervisor. Under test facility procedures, removing a test coupon from its qualified position without the test supervisor’s approval counts as a failed test, so there is no flipping the plate to “get a better angle.” Workmanship discipline counts as much as raw skill: clean between passes, keep your stinger and ground lead from striking arc on the coupon, stay inside the WPS ranges for current and travel speed, and never grind a weld to make it look better.

As the AWS explains of welder performance qualification, the point is to prove you can produce sound welds repeatably under code conditions, not once under ideal ones. Calm beats adrenaline on test day. Visualize the sequence the night before: fit-up check, root, clean, fill, clean, cap. If something goes wrong mid-pass, finish the pass properly, gouge or grind it out, and keep going.

One honest reassurance: as qualification specialists at Weld Cert Test point out, retests are normal and follow the governing standard’s rules. But one disciplined first attempt is cheaper, faster, and far easier on your confidence than any retest. Fix the habits, not just the weld.

After the Test: Records, Continuity, and Choosing 3G vs 3G/4G vs 6G

Passing the bend test is the hard part. What happens next is paperwork, but don’t underestimate it. The documents you leave with decide whether that skill actually gets you hired six months from now, and whether you ever have to sit a coupon in front of a supervisor again.

What You Actually Earn: The WPQR

A passed 3G test produces a Welder Performance Qualification Record (WPQR) — a signed document listing the process, positions, material, thickness, filler classification, and test results your employer (or the test facility) must retain. As AWS itself explains in its breakdown of welder performance qualification versus welder certification, this record is fundamentally different from a certification. It proves this welder, tested on this coupon, under this procedure met the acceptance criteria. It is not a portable license.

Employers are the record keepers. If you change companies, the new employer can rely on your previous WPQR only if they obtain a written statement verifying continuity, or they can simply re-test you on their own WPS. Many welders lose jobs over this technicality, not over skill.

The AWS National Registry and the Wallet Card

There is a more portable option. If you test at an AWS Accredited Test Facility (ATF) under standard QC47, your results can be entered in the AWS National Registry of Certified Welders (NRCW), and you receive a wallet card listing your qualified processes and positions. That card is what people colloquially mean when they say “3G certified.” It is still not a government license — it is a registry entry that any ATF or employer can verify, and it makes job hunting across state lines far easier.

Continuity: The Rule That Quietly Expire Your Qualification

This is the detail welders forget. Under AWS programs, welder continuity is commonly documented on a six-month cycle, renewed by showing you have actively used the qualified process. Stop welding for six months without documentation and your status lapses; you are then re-tested. Employers track this on continuity records, and inspectors occasionally audit them on structural jobs. If you take extended leave, go back to school, or sit out a slow winter, get something in writing before you stop welding.

If you fail a test, retest rules come from the governing standard — AWS B2.1 fills that role when no other code applies — and the test specimens are typically retained at least 30 days. Documented failure and retest history is normal industry practice, not a black mark. See how qualification tests are structured and retried for a fuller picture of retest administration.

Choosing Your Credential: 3G, 3G/4G, or 6G

Which test you take should match the work you actually want. Here is the honest comparison:

Credential	What It Qualifies	Best For	Trade-Off
3G plate only	Groove 1G/2G/3G, fillet 1F/2F/3F	Entry-level structural jobs	No overhead; limited thickness
3G + 4G (1 in coupon)	All groove and fillet positions, unlimited thickness	Ironworkers, bridges, heavy structural	Two coupons, two costs, more prep
6G pipe	Fixed incline pipe groove, all positions	Pipeline, pressure piping, refinery work	Higher skill ceiling, higher pay

The combined 3G/4G plate qualification with a 1-inch coupon is the most comprehensive structural plate credential you can hold, and many heavy fabrication and ironworker contracts specifically call for the D1.1 plate qualification rather than any pipe test. Conversely, if your ambition is pipeline or pressure work, the 6G is the recognized high-value milestone, but no structural foreman will accept it in place of a D1.1 plate coupon if that is what the job specification demands. Aim for both eventually; start with the one your target employer lists in its job ads.

A Realistic 4-Week Preparation Plan

Before you pay for an official test slot, follow this sequence, which mirrors how trade programs prepare candidates (see Portland Community College’s qualification overview for institutional context):

1. Week 1: Run vertical-up scrap beads at chest height on 3/8-inch plate. Check each with a straightedge and grinder. Adjust amperage in 5-amp increments only.
2. Week 2: Repeat the actual coupon setup — backing bar, root opening, tacks — until you can do it from memory. Read the WPS line by line.
3. Week 3: Full mock coupons in your target process (see the SMAW 3G procedure walkthrough), with a second person visually inspecting each one before you cut it.
4. Week 4: Timed test-day simulations: preheat, weld, clean, present for inspection, without removing the plate from position. Practice the discipline, not just the arc.

Back to the Foreman’s Question

That welder in the opening story left with a work order because he understood more than a puddle. He knew his WPQR would follow him, that continuity required documentation, and that the 3G alone might not have been enough for the structural contracts he wanted. Book the test, yes. But book it knowing exactly what it buys you and what to do with it afterward.

Frequently Asked Questions

What does a 3G welding test qualify me to do?

Under AWS D1.1, a 3G plate groove test qualifies you to weld groove welds in the flat (1G), horizontal (2G), and vertical (3G) positions, plus fillet welds in 1F, 2F, and 3F. It does not cover overhead (4G/4F), which requires a separate 4G test or a combined 3G/4G qualification.

Is the 3G test welded vertical-up or vertical-down?

Structural 3G qualification is almost always welded vertical-up (progression specified on the WPS). Vertical-up gives the puddle a solid shelf to sit on and produces the penetration the code requires; test WPSs such as NCDOT’s D1.5 bridge procedure explicitly specify vertical-up progression.

How thick is a typical 3G test plate?

Most 3G tests use a 3/8 in (10 mm) plate, commonly ASTM A36, with a single-V groove at about 22.5° per side and a 1/4 in root opening against a backing bar. A 3/8 in coupon typically qualifies production groove welds up to 3/4 in, while a 1 in test coupon extends to unlimited thickness.

What tests are performed on a 3G coupon after welding?

First, a Certified Welding Inspector performs visual inspection of the as-welded coupon — if it fails, testing stops. If it passes, the coupon is sectioned into bend specimens (commonly two face bends and two root bends), which are bent 180° in a guided bend jig; in some programs, radiography can substitute for bend tests (but not for GMAW short-circuit transfer under D1.1).

What will fail a bend test?

Any single open discontinuity larger than 1/8 in in any direction on the convex surface of the bent specimen fails the test. Corner cracks up to 1/4 in are acceptable unless they trace to slag or fusion-type defects; smaller indications between 1/32 in and 1/8 in must not total more than 3/8 in combined.

What is the difference between a 3G and a 4G weld test?

The 3G coupon is clamped vertically and welded uphill; the 4G coupon is clamped horizontally above the welder and welded overhead. A standalone 3G covers 1G/2G/3G groove and 1F/2F/3F fillet, while a standalone 4G covers 1G/2G/4G groove and 1F/2F/4F fillet — so taking both together is the only way to cover all positions on plate.

Does a 3G certificate make me ‘AWS certified’?

A passed test gives you a Welding Performance Qualification Record (WPQR) — the code-based qualification document held by your employer or test facility. If you test at an AWS Accredited Test Facility under QC47, you can also be listed in the AWS National Registry of Certified Welders, which is the separate AWS Certified Welder program.

How long does a 3G qualification stay valid?

Qualification does not expire automatically, but AWS programs require documented continuity — typically proof that you have actively welded the process within the last six months, recorded on a continuity card or record. Without continuity, you may need to retest under the governing standard’s rules.