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AWS D1.1 PLATE TEST

3G/4G All-Position Plate Qualification

One combined test covers every groove and fillet position plus unlimited thickness. The single most valuable plate certification under AWS D1.1 — and you can mail us your plates from anywhere in the country.

Get a Quote ✆  (404) 860-1288 How It Works
2
Test Plates
One 3G + one 4G
All
Groove Positions
1G, 2G, 3G, 4G covered
All
Fillet Positions
1F, 2F, 3F, 4F covered
Thickness
Unlimited with 1″ plate
✓  AWS CWI Inspected ✓  Accredited Bend Testing ✓  Official WPQ Issued ✓  Mail-In Nationwide ✓  D1.1 Table 6.10 Compliant

What Is the 3G/4G Combined Plate Qualification?

The AWS D1.1 3G/4G combined plate qualification is the most comprehensive groove weld certification available for structural plate welding. By completing two test plates — one in the 3G (vertical uphill) position and one in the 4G (overhead) position — a welder earns approval for every groove and fillet weld position recognized by the structural welding code.

No other plate test comes close in coverage. The 6G pipe test is the only comparable credential, but many structural fabricators and ironworker contractors specifically require the D1.1 plate qualification. When a contractor says they need welders who are "all-position certified," this is what they mean.

Technical diagram showing 3G vertical uphill welding position on left with weld progression arrow, and 4G overhead position on right with travel direction arrow, on dark background with yellow labels
3G vs. 4G positions: The 3G test plate is oriented vertically and welded uphill. The 4G test plate is horizontal overhead, welded horizontally. Together they cover the two most demanding positions in structural welding.

What Is the 3G Position?

In the 3G position, the test plate is oriented vertically — the joint runs up and down, and the welder progresses upward (vertical uphill). This is the standard for welding structural columns, vertical seams on tanks, and any joint where the plate stands on edge. Gravity constantly works against the weld puddle, requiring the welder to control heat input and travel speed precisely to prevent the molten metal from running downward.

Vertical uphill welding produces a stronger, more consolidated weld than vertical downhill, which is why AWS D1.1 defaults to uphill progression for groove welds on thicker material. On the 3G test, you'll typically run a root pass, multiple fill passes, and a cap pass — all while fighting gravity on a live puddle.

What Is the 4G Position?

In the 4G position, the test plate is positioned horizontally overhead — the welder looks up at the joint and welds from below. The groove points downward. Every ounce of molten metal wants to drip onto the welder's face. It is widely considered the most physically demanding test position in structural welding.

The 4G test requires short arc length, controlled heat input, and deliberate travel to keep the puddle from sagging. Most welders find the 4G position significantly more difficult than the 3G, and it's often where an otherwise strong candidate comes undone. Passing the 4G is a genuine statement of skill.

Professional welder in full leather PPE and welding helmet performing overhead groove weld with bright arc and sparks falling, plate positioned horizontally above in steel welding fixture
4G overhead welding in practice: The welder braces arms against the fixture for stability. Sparks fall continuously. Short arc length and controlled travel speed are critical — the puddle will sag if heat gets away from you.

Why Both Positions Together?

AWS D1.1 Table 6.10 defines what each qualification test covers. The logic is that if you can weld a sound groove joint in the hardest positions — vertical and overhead — you can certainly weld in the easier ones (flat and horizontal). Qualifying in both 3G and 4G simultaneously gives you full coverage of all positions in a single test session.

D1.1 Table 6.10 — What the Combined 3G/4G Test Qualifies:

Groove positions covered: 1G (flat), 2G (horizontal), 3G (vertical), 4G (overhead)  |  Fillet positions covered: 1F, 2F, 3F, 4F  |  Plate thickness: Unlimited (with 1" test plate)

Position Coverage Matrix

AWS D1.1 position coverage by test type
Test 1G Flat 2G Horiz. 3G Vert. 4G OH All Fillets Unlim. Thick.
1G Only
2G Only
3G Only
4G Only
3G + 4G Combined

Test Plate Specifications

Both the 3G and 4G test plates use identical joint preparation. The joint detail below is the standard AWS D1.1 prequalified joint — a complete joint penetration (CJP) single V-groove with a steel backing bar. This joint geometry is used throughout structural steel construction, so the test reflects real-world conditions.

Blueprint-style cross-section diagram showing 45 degree included V-groove angle with 22.5 degrees per side, 1/4 inch root opening, 1 inch thick test plates, and 1/4 by 1 inch backing bar with yellow dimension callouts
Standard joint detail per AWS D1.1: 45° included angle (22.5° per side), 1/4″ root opening, knife-edge prep, and 1/4″ × 1″ A36 backing bar. This joint geometry appears thousands of times daily in structural steel construction.
Plate Material
ASTM A36 Structural Steel
Plate Thickness
1 inch (unlimited qualification)
Groove Angle
45° included (22.5° per side)
Root Opening
1/4 inch (0.25")
Root Face
Knife edge (0" land)
Backing Bar
1/4" × 1" × 8" A36
Joint Type
CJP Single V-Groove
D1.1 Reference
Table 6.10 / Clause 4
Two beveled steel test plates mounted vertically in a welding fixture showing the V-groove joint with 1/4 inch root opening ready for 3G vertical qualification welding
3G plate setup — ready to weld: Both 1-inch plates are beveled to 22.5° per side and mounted vertically in a welding positioner/fixture. The V-groove with 1/4″ root opening is clearly visible. The backing bar is tack-welded behind the joint.

How to Prepare Your Test Plates

Proper plate preparation is not just about following the code — it's about setting yourself up for a clean, consistent weld. Sloppy prep creates problems in the groove that no amount of skill can overcome.

  1. Cut and dimension your plates

    Cut two plates to approximately 1" × 6" × 4" from ASTM A36 stock. Verify material certification or use certified plate. Edges must be clean and straight before beveling.

  2. Bevel the groove faces

    Bevel each plate to 22.5° per side using a grinder, torch, or beveling machine. The bevel face should be smooth with no gouges or torch drag. Check your angle with a protractor — an undersized bevel will trap slag in the root.

  3. Prep a knife-edge root face

    Grind the root face to a true knife edge (0" land). Any land will reduce root fusion access. The knife edge breaks down into the root opening and allows full penetration to the backing bar.

  4. Set up and tack the backing bar

    Position the backing bar (1/4" × 1" × 8" A36) behind the joint, centered under the root opening. Tack weld at the ends only — do not tack through the groove area. The backing bar must be in complete contact with both plates across the full length.

  5. Set and verify root opening

    Use a feeler gauge or spacers to verify a consistent 1/4" root opening across the full length. A gap that opens or closes along the joint will cause variable root fusion. Tack weld lightly at both ends to hold the gap before positioning.

  6. Position in the fixture and clean

    For the 3G plate, mount vertically in a welding fixture or clamp to a welding table at 90° to the floor. For 4G, the plate must be truly horizontal above you. Wipe the groove faces with acetone or a clean rag to remove all oil, moisture, and mill scale from the weld zone.

Approved Welding Processes

Each welding process is tested and qualified separately. A welder who passes the 3G/4G test with SMAW is qualified for all positions with SMAW only. To be qualified with FCAW-G as well, the welder must take a separate 3G/4G test with FCAW-G. Most job sites specify which process they require before testing begins.

Split comparison image showing SMAW stick welding on left with E7018 electrode and yellow SMAW Stick label, and FCAW flux core welding on right with MIG gun nozzle and blue arc with FCAW Flux Core label
SMAW vs. FCAW — the two most common processes for D1.1 structural plate qualification. SMAW (Stick) with E7018 electrodes is the traditional standard. FCAW (Flux Core) is favored in high-production environments for its faster deposition rate.

SMAW — Shielded Metal Arc (Stick)

  • Most common process for D1.1 structural testing
  • E7018 low-hydrogen electrode is standard
  • E7018 must be stored in a rod oven — moisture causes hydrogen cracking
  • 3G: 3/32" or 1/8" electrodes preferred for root, fill, and cap
  • 4G: 3/32" electrodes with reduced amperage control the puddle overhead
  • Widely accepted by all contractors and inspection authorities

FCAW-G — Gas-Shielded Flux Core

  • Higher deposition rate than SMAW — faster to fill the groove
  • Requires shielding gas (typically 75% Ar / 25% CO₂ or 100% CO₂)
  • Common wire: E71T-1C or E71T-1M depending on gas mix
  • 3G settings critical — too hot causes sag on vertical
  • Widely used in fabrication shops and on-site structural steel

FCAW-S — Self-Shielded Flux Core

  • No external shielding gas required — good for outdoor work
  • E71T-8 or E71T-11 are common wires for structural work
  • Preferred for field welding in wind where gas shielding is impractical
  • Check with your inspector that the wire meets D1.1 approved filler requirements

GMAW — Gas Metal Arc (MIG)

  • Short circuit transfer used for 3G and 4G positions
  • ER70S-6 wire most common for structural steel
  • Less common on D1.1 structural sites — some contracts prohibit GMAW short-arc on thicker material
  • Pulse GMAW increasingly accepted on high-production projects
Process Comparison for 3G/4G Structural Plate
Factor SMAW (E7018) FCAW-G FCAW-S GMAW
Overhead (4G) ControlExcellentGoodGoodModerate
Deposition RateLowHighModerateModerate
No Gas Cylinder NeededYesNoYesNo
Field / Outdoor ReadyYesNoYesNo
D1.1 AcceptanceUniversalUniversalCommonCheck specs
Slag Removal RequiredYesYesYesNo
Close-up of leather-gloved hand holding E7018 stick electrode against vertical steel plate performing 3G uphill SMAW welding, showing bright arc, consistent weld bead progressing upward, and heat affected zone
SMAW 3G technique — electrode angle: For vertical uphill welding, the electrode is held perpendicular to the plate face (90° work angle) with a 5°–15° uphill travel angle — tilted slightly in the direction of travel. The completed passes below the arc show consistent width and a slight convex profile.

3G Vertical Uphill Welding Technique

The 3G position demands disciplined technique more than raw skill. The three killers are too much heat, too fast a travel speed, and too long an arc. Master those three variables and the rest follows.

Root Pass (3G)

  • Run a stringer bead — no weave on the root
  • Point into the root opening; aim for both bevels and the backing bar
  • Keep arc length tight — 1× to 1.5× electrode diameter maximum
  • Travel uphill at a consistent pace; pause slightly at each toe to avoid undercut
  • Watch for the keyhole — it tells you you're achieving full penetration

Fill and Cap Passes (3G)

  • Remove all slag completely before each pass — use a grinder if needed
  • A slight "J" or upside-down "V" weave is acceptable for fill passes
  • Pause at each toe to tie into the bevel face; this prevents undercut
  • Keep reinforcement under 3/16" on the cap
  • Final cap pass — keep travel speed consistent to avoid high/low profile

Heat Management (3G)

  • Use lower amperage than flat position — gravity helps the puddle flow
  • For SMAW E7018 3/32": typical range 70–90 amps for fill on 3G
  • If the puddle starts to drip, reduce amperage or slow travel
  • Allow brief interpass cooling — don't run back-to-back passes when plate is cherry red
  • Check interpass temp if your WPS specifies a maximum

Common 3G Mistakes

  • Root pass too cold — incomplete fusion to backing bar (automatic fail)
  • Weaving too wide on root — creates slag traps
  • Undercut on the cap toes — caused by dwelling too long at the edges
  • Arc strikes outside the weld zone — automatic rejection per D1.1
  • Inconsistent travel speed — creates high/low profile that fails visual

4G Overhead Welding Technique

The 4G test is where most people struggle. Everything about overhead welding fights the physics — molten metal wants to come down, your body position is awkward, and fatigue sets in fast. The key is bracing, short arc, and accepting that overhead welds look different from flat ones. A slightly convex, narrower bead is normal and acceptable.

Body Position and Bracing

  • Brace both elbows against your body or the fixture whenever possible
  • Crouch or kneel to position your head below the work — don't just look straight up
  • Use a slag shield or weld blanket — overhead spatter burns are serious
  • Wear full leather — jacket, gloves, helmet with rear neck protection

Root Pass (4G)

  • Keep the arc extremely tight — longer arc = puddle sag
  • Move slightly faster than you think you need to
  • Use 3/32" electrodes (SMAW) for better puddle control than 1/8"
  • A small, slightly narrow bead is better than a wide sagging bead
  • Chip and grind every pass more aggressively than you would on flat

Fill and Cap Passes (4G)

  • Build up in multiple narrow stringers — avoid weaving overhead
  • Each pass should be narrower than on 3G to control the puddle
  • Tie in tightly to each previous bead — no gaps, no overlap humps
  • Keep cap reinforcement under 3/16" — a high cap is a common failure

Heat and Interpass (4G)

  • Run slightly lower amperage than 3G fill passes
  • Allow adequate interpass cooling — hot plate + overhead = sag
  • Keep shielding gas flow at the higher end of range if using FCAW-G
  • Grind flush any high spots between passes to keep a consistent groove profile

Visual Inspection Requirements

Before a single bend specimen is cut, both plates must pass a visual inspection by an AWS Certified Welding Inspector (CWI). This inspection is performed per AWS D1.1 Clause 4.9 — the same acceptance criteria used for production structural welds. It is not a courtesy check; it's a codified acceptance test.

Failing visual inspection means the plate does not proceed to bend testing. There is no second chance on the same plate.

Visual Inspection Acceptance Criteria — AWS D1.1 Clause 4.9
Discontinuity Type Acceptance Limit Notes
CracksNone permittedAny crack = reject
Incomplete fusionNone permittedAnywhere in the joint
Undercut (groove welds)≤ 1/32" (0.8mm)Maximum depth at toe
Weld reinforcement≤ 3/16" (4.8mm)Height above base metal surface
Arc strikesNone outside weld zoneAutomatic rejection
OverlapNone permittedWeld metal must not flow over base metal
PorosityRefer to D1.1 Clause 4.9.3Size and frequency limits apply
Root surface (with backing)CJP requiredFull tie-in to backing bar required

Guided Bend Testing

Plates that pass visual inspection are sent to an accredited testing laboratory for guided bend testing. This is the definitive mechanical test for weld quality. There is no visual evaluation here — the plate tells the story by either cracking or not cracking under a controlled 180-degree bend.

Two bent weld test specimens showing U-shaped 180-degree guided bend results on a welding workbench with MIG welder in background
Passing guided bend specimens: Each specimen has been bent 180° into a U-shape in the guided bend jig. The outer convex surface (where tension develops) is inspected for cracks or discontinuities. These specimens show no relevant cracks — a passing result.
Red guided bend test machine with weld specimen being pressed into U-shape between die blocks in a professional testing laboratory with microscopes and testing equipment visible in background
Guided bend test machine in action: The plunger presses the specimen into a die with precisely controlled dimensions per AWS D1.1. The two support blocks force the specimen into a U-shape. The weld, now on the outer convex surface, is subjected to maximum tensile stress — exposing any lack of fusion, porosity, or cracking.

Bend Test Procedure and Acceptance

Specimens Per Plate
4 (2 face, 2 root)
Total Bend Tests
8 (4 per plate × 2 plates)
Bend Angle
180 degrees
Backing Bar Removal
Removed before bending
Max Discontinuity
1/8" in any direction
Corner Cracks
Up to 1/4" (if no slag)

A face bend specimen has the face (cap) of the weld on the convex (outside) of the bend — maximum tension on the weld face. A root bend specimen has the root of the weld on the convex outside — maximum tension on the root. If any single specimen shows a discontinuity greater than 1/8" in any direction, the entire test fails.

Common Test Failures — And How to Avoid Them

These are the most frequent reasons welders fail the 3G/4G test. Each one is preventable with proper technique and preparation.

Incomplete Root Fusion

The root pass fails to fully fuse to the backing bar across the entire length. This is the most common bend test failure. Cause: arc too short to reach the backing bar, or root opening inconsistent. Fix: slightly higher amperage on root pass, verify 1/4" gap is consistent before welding, use a tight arc aimed directly at the root.

Slag Inclusions

Trapped slag from incomplete interpass cleaning shows up as linear discontinuities on the bend specimens. Cause: chipping lightly and welding over unfused slag. Fix: chip every pass thoroughly, use a wire wheel on a grinder, and grind flush any high spots that trap slag at the toes.

Undercut Exceeding 1/32"

Undercut at the toes of the cap pass exceeds the 1/32" visual limit, causing failure before bend testing even begins. Cause: dwelling too long at the toes of a weave bead, excessive amperage on cap. Fix: reduce amperage on cap pass, pause longer at center of weave rather than toes.

Arc Strikes Outside Weld Zone

Even a single arc strike on the base metal adjacent to the weld is an automatic rejection per D1.1 Clause 4.9. Cause: poor electrode angle, brushing the plate while starting. Fix: use a scrap piece to strike the arc, then bring it into the joint. Inspect the plate before submitting.

4G Puddle Sag / Overlap

The overhead puddle runs and overlaps the base metal, creating a visual failure and potential lack of fusion. Cause: arc length too long, amperage too high, travel speed too slow. Fix: tight arc, reduce amperage 10–15% from 3G setting, move slightly faster and build up in narrower stringer passes.

Wet or Contaminated Electrodes

Moisture in E7018 low-hydrogen electrodes causes porosity and hydrogen-induced cracking — both bend test failures. Cause: electrodes stored outside a rod oven, or used from an unsealed container. Fix: store E7018 in a heated rod oven at 250°–300°F minimum. Never use electrodes that have been exposed to humidity overnight.

The WPQ Document — Your Qualification Record

When your plates pass both visual and bend testing, the AWS CWI who performed the inspection signs a Welder Performance Qualification (WPQ) record. This document is the official record of your certification. It identifies you by name, lists the welding process, positions, electrode or wire, base metal, test date, and the CWI's signature and certification number. It is issued per AWS D1.1 Annex N (or similar form) and is the document your employer and their clients will request.

Welder Performance Qualification Record document on wooden desk showing fields for welder name, process, position, test date, and certified welding inspector signature line, with hard hat and welding gloves in background
Welder Performance Qualification (WPQ) document: The official record signed by a Certified Welding Inspector. This is the document your employer, the general contractor, and project inspectors will ask for. WeldCertTest issues WPQ records on all passing test results.

What Goes on the WPQ Record

  • Welder's full legal name and employer
  • Welding process (SMAW, FCAW-G, etc.) and filler metal classification
  • Test position(s) — 3G and 4G listed explicitly
  • Base metal type and thickness tested
  • Joint type (single V-groove CJP with backing)
  • Visual inspection results and date
  • Bend test results and laboratory name
  • CWI name, certification number, and signature
  • Statement of qualification scope (all positions, unlimited thickness)
  • Continuity requirement statement (6-month rule)

How Long Does the Certification Stay Valid?

Per AWS D1.1 Clause 4.25, a welder's performance qualification remains valid indefinitely — but with one important condition: the welder must have welded using that qualified process at least once within the preceding six months. This is called the continuity requirement.

If a welder hasn't used their SMAW qualification for more than six months, they must either demonstrate that they have welded that process (employer sign-off in a continuity log) or re-qualify. Employers are required to maintain a continuity log showing periodic sign-offs. A lapsed qualification cannot simply be "reactivated" with a phone call — it requires re-testing.

✓ Pro Tip for Employers: Set a calendar reminder every 5 months to review your continuity log. A qualification that lapses because no one remembered to sign off costs the same as a brand-new test — and may delay a job start. WeldCertTest can help with re-qualification if continuity has been broken.

3G/4G Plate vs. 6G Pipe Qualification

This is one of the most common questions contractors ask. Both the 3G/4G plate and the 6G pipe test provide all-position qualification, but they are different credentials used in different contexts.

Factor 3G/4G Plate (D1.1) 6G Pipe
Code Governed ByAWS D1.1 StructuralAWS D1.1, ASME, API
Test PieceFlat plateRound pipe (inclined 45°)
DifficultyHighHigher
Covers Plate PositionsYes — allYes — all
Covers Pipe PositionsPipe ≥ 24" OD onlyYes — all diameters
Required for Structural SteelCommon requirementSometimes accepted
Required for Pressure PipingNoYes (ASME)
Required for ShipyardsOften specifiedSometimes accepted
WPS RequiredYesYes
D1.1 Table ReferenceTable 6.10Table 6.10

The bottom line: if the work is structural steel — buildings, bridges, heavy equipment — and it's governed by AWS D1.1, the 3G/4G plate is what's required. If the work involves pressure piping or process pipe, 6G is the credential. Many experienced welders hold both.

AWS D1.1 vs. ASME Section IX Qualification

AWS D1.1 and ASME Section IX are separate welding codes with different qualification requirements. A welder certified under one is not automatically certified under the other.

Factor AWS D1.1 ASME Section IX
Governed ByAmerican Welding SocietyASME Boiler & Pressure Vessel
Applies ToStructural steel, bridges, buildingsPressure vessels, boilers, piping
Position Designation1G, 2G, 3G, 4G, 5G, 6G1G, 2G, 3G, 4G, 5G, 6G (same numbers)
WPS RequiredYesYes
CWI RequiredYesYes
WPQ Expires6-month continuity6-month continuity (same)
Portable Between EmployersYes (with continuity record)Yes (with continuity record)
Cross-RecognitionNot automaticNot automatic

Where the 3G/4G Qualification Is Required

The AWS D1.1 3G/4G combined plate qualification is required or strongly preferred across a wide range of structural industries. If you're a contractor building a hiring list, or a welder looking to maximize your hire-ability, this is the credential that opens the most doors.

Wide angle view of bridge construction over river with welder in full PPE welding vertical steel column joint with sparks, surrounded by ironworkers in safety vests and hard hats under dramatic cloudy sky
Bridge and structural steel construction: Welders on large-scale structural projects are routinely required to provide documentation of their 3G/4G AWS D1.1 qualification before they are permitted to weld on the job. No card, no work.

Structural Steel Fabricators

Fabrication shops producing beams, columns, and frames for buildings must qualify welders per D1.1 to meet project specifications and third-party inspection.

Bridge Construction

AASHTO/NSBA bridge projects require AWS D1.5 or D1.1 welding. Most state DOT bridge contracts explicitly call out all-position plate qualification for groove welds.

Shipyards and Marine

Ship hull and structural welding follows AWS D1.1 or Navy/Class Society standards. All-position qualification is standard — hulls have welds in every conceivable orientation.

Ironworkers

Union ironworker contractors and open-shop structural erectors require all-position D1.1 certification for field welders before they set foot on a structural project.

Heavy Equipment OEMs

Manufacturers of cranes, mining equipment, and heavy industrial machinery producing welded structural frames under D1.1 require qualified welders for all structural joints.

Power and Energy Infrastructure

Transmission towers, wind turbine towers, and substation structures are built to D1.1. All-position groove weld qualification is required for most structural weld joints.

State Contractor Requirements — Do Your Welders Need This?

Public infrastructure projects in most states require welder qualification documentation as a condition of contract. While the specific requirements vary by state, project type, and contract language, the AWS D1.1 3G/4G combined plate qualification is the most widely recognized credential across all states for structural steel groove welding. Below is a representative overview.

California
Caltrans requires D1.1 welder qualification. AWS CWI inspection required on state projects.
Texas
TxDOT bridge projects require D1.5/D1.1 qualification. All-position cert widely required by contractors.
Florida
FDOT structural steel projects require D1.1 or D1.5 welder qualification per contract specs.
New York
NYC DOB and NYSDOT projects require AWS welder certification. Ironworkers Local contracts specify position qualifications.
Illinois
IDOT and Illinois Tollway structural contracts reference D1.1 welder qualification documentation.
Pennsylvania
PennDOT bridge and structural projects require D1.5 or D1.1 qualification with CWI inspection.
Ohio
ODOT structural steel projects require AWS D1.1 welder qualification. All-position cert preferred.
Georgia
GDOT and private fabricators operating under D1.1 require position qualification documentation.
All Other States
Public infrastructure, DOT bridge, and heavy industrial contracts typically reference D1.1. Check project specs — the 3G/4G combined qualification is universally accepted.
Note: State requirements are set by individual project specifications and may reference AWS D1.1, D1.5 (bridges), or AWS D1.6 (stainless). Always confirm which code governs your project before scheduling welder qualification testing. WeldCertTest provides D1.1 structural plate qualification.

Who Needs This Test — Contractors vs. Individual Welders

Quick Guide: Is the 3G/4G Combination Right For You?

You're a contractor with multiple welders:
You want the 3G/4G combined test. It provides the broadest qualification scope, reduces the chance of a welder being turned away at a job site, and simplifies your continuity log. One test covers every groove position your welders will encounter on structural projects.
You're an individual welder seeking employment:
The 3G/4G combined is the resume credential. It tells every structural contractor "I can weld in any position." If you only have the 3G or only the 4G, some employers will accept it — but you'll be turned away by others. The combined test is the safe choice if you want maximum employability.
You need to qualify for a specific project with limited positions:
If the contract only has flat and horizontal groove welds, a 2G test may suffice and cost less. Read the project's welding specification before testing. If it calls for "all-position qualification," you need 3G/4G. When in doubt, test 3G/4G — you'll never be over-qualified.
You failed the 4G and passed the 3G:
You hold a valid 3G qualification that covers 1G, 2G, 3G, and all fillet positions — but not 4G. You can work on most structural projects that don't involve overhead groove welds. Schedule a 4G re-test when you're ready; you don't need to re-test the 3G.

WeldCertTest Mail-In Qualification Service

You don't need to travel to a testing facility. WeldCertTest handles AWS D1.1 3G/4G plate qualification through a straightforward mail-in process. Your welder completes the plates under your WPS at your shop. You ship them to us. We handle everything from there.

  1. Contact us for a quote and WPS

    Call or email to confirm the process (SMAW, FCAW, etc.) and we'll provide pricing and a qualified WPS for your welder to work under. If you already have a D1.1 prequalified WPS, you may use it.

  2. Weld your plates at your shop

    Your welder completes both the 3G and 4G plates per the WPS at your facility. No travel required. No scheduling around a test facility's availability.

  3. Ship the completed plates to us

    Follow our shipping instructions (found at weldcerttest.com/shipping.html). Ship both plates together. Standard ground shipping works fine — test plates are not fragile.

  4. CWI visual inspection

    Our AWS Certified Welding Inspector performs a full visual inspection per D1.1 Clause 4.9. If the plates pass visual, they move to bend testing. We'll contact you if there is a visual rejection before proceeding.

  5. Accredited laboratory bend testing

    All bend testing is performed by an accredited third-party laboratory. Specimens are cut, prepared, and bent per D1.1 requirements. Results are documented with full test data.

  6. WPQ issued and delivered

    On passing, the AWS CWI signs and issues the official Welder Performance Qualification record. The WPQ is sent to your company by email and mail. Typical total turnaround: see our timeframes page.

✓ Why Mail-In Works: AWS D1.1 does not require the CWI to be present while welding. The test plate itself is the evidence of the welder's skill — that's the whole point of the performance qualification. As long as the welder welded the plates under a qualified WPS, the CWI's inspection of the completed plates is fully code-compliant.

How Much Does the 3G/4G Qualification Cost?

The total cost of a 3G/4G combined plate qualification includes test plate material, CWI inspection time, accredited bend testing, and WPQ documentation. For a single welder, the combined 3G/4G test is typically more cost-effective than testing each position separately, since the CWI inspection and lab processing are shared across both plates.

Cost factors that affect pricing include the welding process (some processes require more bend specimens), the number of welders being tested at the same time, and whether you need expedited turnaround. Contractors qualifying multiple welders at once often receive volume pricing.

Contact WeldCertTest at (404) 860-1288 or request a quote online for current pricing. We'll confirm process, plate count, and turnaround before you commit to anything.

Separate vs. Combined Testing — Cost Efficiency
Option Plates Positions Covered Relative Cost Recommended?
3G only11G, 2G, 3G, all filletsLowerOnly if 4G not needed
4G only11G, 2G, 4G, all filletsLowerOnly if 3G not needed
3G + 4G Combined2All positions + unlimited thicknessModerateYes — best value
3G + 4G Separate sessions2 (separate)All positionsHigherOnly if timing differs

Glossary of Key Terms

New to the qualification process? Here are the terms you'll see on your paperwork and hear from your inspector.

WPQ — Welder Performance Qualification

The official AWS document certifying that a welder has demonstrated the ability to produce a sound weld under a specific WPS. Signed by a CWI.

WPS — Welding Procedure Specification

A document specifying the required variables for a specific weld: process, position, base metal, filler metal, preheat, interpass temperature, and more. Welders must be tested under a qualified WPS.

CWI — Certified Welding Inspector

An AWS-certified inspector qualified to evaluate welds, review documentation, and sign WPQ records. Certification is issued by the American Welding Society after examination.

CJP — Complete Joint Penetration

A groove weld that has full fusion through the entire thickness of the joint, including the root. The 3G/4G test uses a CJP single V-groove with backing.

3G Position

Vertical groove weld position per AWS D1.1. The plate is oriented vertically and the weld progresses uphill. One of the two most demanding plate positions.

4G Position

Overhead groove weld position per AWS D1.1. The plate is horizontal overhead and the weld is made from below. The most physically demanding test position.

Guided Bend Test

A mechanical test where weld specimens are bent 180° over a mandrel of specified radius. Used to verify fusion, ductility, and absence of defects.

Continuity (6-Month Rule)

AWS D1.1 Clause 4.25 requirement that a welder must use their qualified process at least once every 6 months or the qualification expires.

E7018 Electrode

A low-hydrogen, iron powder SMAW electrode. The "70" indicates 70,000 PSI minimum tensile strength. The "18" indicates a low-hydrogen coating requiring storage in a rod oven.

FCAW — Flux-Cored Arc Welding

A wire welding process using a tubular wire filled with flux. FCAW-G uses external shielding gas; FCAW-S is self-shielded. Both are approved under AWS D1.1.

Backing Bar

A steel bar placed behind the root of a groove joint to support the root pass. Per D1.1, the backing bar is steel and remains in the joint after welding (permanent backing).

Root Opening

The gap between the two base metal pieces at the root of the joint before welding. For the 3G/4G D1.1 test, this is 1/4 inch (0.25").

Practice Guide — Getting Ready to Pass

Don't show up for the 3G/4G test without practice time on both positions. The 4G overhead position in particular requires physical conditioning — you cannot train your body to weld overhead on test day. Here's how experienced welders prepare.

Recommended Practice Sequence

  1. Start with flat position (1G) to get your parameters dialed in — amperage, arc length, travel speed.
  2. Move to horizontal (2G) to start managing a puddle that wants to drip.
  3. Run multiple 3G plates before test day. Focus on root fusion first. Then clean technique on fill passes. Then cap pass consistency.
  4. Spend the most practice time on 4G overhead. Run at least 4–5 complete test plates in overhead before you test.
  5. Practice your bracing position — where your elbows and arms rest during overhead welding. Find a body position that lets you maintain a tight arc without shaking.
  6. On your last practice plate before test day, do a self-evaluation: look for undercut, check reinforcement height, inspect for arc strikes. Fix your habits before the official test.
✓ Simulate test conditions during practice. Use the exact electrode size, brand, and amperage you'll use on test day. Run the plates in the same sequence you'll run them for the real test. The goal is to eliminate surprises — the only thing new on test day should be the fresh plates.

Related Qualifications

Not sure whether the combined test is right for your situation? Explore individual position qualifications or other testing options below.

3G Vertical Only

Qualifies 1G, 2G, 3G, and all fillet positions. Does not include overhead. Lower cost option when overhead is not required.

4G Overhead Only

Qualifies 1G, 2G, 4G, and all fillet positions. Does not include vertical. Used when overhead is required but vertical is already certified.

6G Pipe Qualification

Inclined fixed-position pipe test. Qualifies all positions on pipe and plate. Required for pressure piping — optional for structural.

Re-Certification

Lapsed qualification? Continuity broken? Our recertification service handles the paperwork and testing to reinstate your credentials.

Frequently Asked Questions

What does the combined 3G/4G test qualify a welder for?
The combined 3G/4G test qualifies for all groove weld positions (1G, 2G, 3G, 4G) and all fillet positions (1F, 2F, 3F, 4F) on structural plate per AWS D1.1 Table 6.10. With a 1-inch test plate, thickness qualification is unlimited. It is the broadest single plate qualification available under D1.1.
How many plates and bend tests are required?
Two test plates are required — one welded in the 3G (vertical uphill) position and one in the 4G (overhead) position. Each plate produces four bend specimens (2 face, 2 root), for a total of 8 guided bend tests. All 8 must pass.
What plate thickness should I use to get unlimited thickness qualification?
Use 1-inch (25mm) ASTM A36 plate. Per D1.1 Table 4.5, a test plate of 1 inch or greater qualifies the welder for unlimited production thickness. A 3/8-inch plate only qualifies up to 3/4-inch production thickness. Most structural contractors require the unlimited thickness qualification — use 1-inch plate.
What is the standard joint configuration for the 3G/4G test?
The standard joint is a single V-groove CJP with 45-degree included angle (22.5 degrees per side), 1/4-inch root opening, knife-edge root face, and a 1/4-inch × 1-inch A36 backing bar. This is a D1.1 prequalified joint per Table 3.2. Both the 3G and 4G plates use identical joint preparation.
Do I need a WPS to take the test?
Yes. AWS D1.1 requires the welder to be tested under a qualified Welding Procedure Specification (WPS). WeldCertTest provides a WPS with each test, or you may use your company's existing D1.1 prequalified WPS. The WPS is referenced on the WPQ document.
What are the most common failure causes on the 3G/4G test?
The top failure causes are: (1) incomplete root fusion on the root bend specimens — the root pass didn't fully tie in to the backing bar; (2) slag inclusions from inadequate interpass cleaning; (3) undercut at the cap toes exceeding 1/32 inch; (4) arc strikes outside the weld zone (automatic visual rejection); and (5) overhead puddle sag causing overlap or lack of fusion on the 4G plate.
How long does the 3G/4G certification stay valid?
Per AWS D1.1 Clause 4.25, the qualification is valid indefinitely as long as the welder uses the qualified process at least once every six months. The employer must maintain a continuity log. If more than six months passes without using that process, the qualification expires and the welder must re-qualify.
Can I mail in test plates, or do I need to weld at your facility?
You can mail in completed test plates. AWS D1.1 does not require the CWI to witness the welding — the inspector evaluates the completed plates. Your welder completes both plates under a qualified WPS at your shop, then ships them to WeldCertTest for CWI visual inspection and bend testing. This is our standard service and it's fully code-compliant.
Does this plate qualification cover pipe welding?
The 3G/4G plate qualification covers structural plate per AWS D1.1. It also qualifies groove welds on pipe or tube with an outside diameter of 24 inches or greater (per D1.1 Table 6.10 footnote). It does not cover pressure piping (ASME B31) or smaller diameter pipe — those require separate pipe qualifications such as 5G or 6G.
What is the difference between the combined 3G/4G and testing each position separately?
The final qualification scope is identical — both qualify the welder for all positions. The combined test is completed in one session and is generally more cost-efficient than two separate sessions. Additionally, many project specifications and contract documents call out "3G/4G combined" by name — having that explicit language on your WPQ avoids any ambiguity.
What's the difference between the 3G/4G plate test and the 6G pipe test?
Both provide all-position qualification, but for different applications. The 3G/4G is a D1.1 structural plate qualification used for buildings, bridges, and heavy steel. The 6G is a pipe qualification (D1.1, ASME, or API depending on the application) required for pressure piping, process pipe, and some structural pipe work. Structural steel contractors generally require the D1.1 plate test; pressure piping contractors require 6G. Many journeyman welders hold both.
How do I maintain my qualification after passing?
Your employer must maintain a continuity log showing you have used the qualified welding process at least once every six months. The log requires sign-offs at each six-month interval. If you change employers, your new employer should obtain your existing WPQ and continue the continuity log — you do not need to re-qualify just because you changed jobs, as long as continuity has been maintained.
Can an employer use a welder's existing WPQ from another company?
Yes. Per AWS D1.1, a welder's qualification is not employer-specific — it travels with the welder. A new employer can accept an existing WPQ as long as: (1) the WPS used for the test is the same as or equivalent to the new employer's WPS; (2) continuity has been maintained; and (3) the qualification has not been revoked for cause. The new employer takes responsibility for continuing the continuity record.
How much does the 3G/4G qualification cost at WeldCertTest?
Contact us for current pricing. Costs include CWI inspection, accredited bend testing, and WPQ documentation. Volume discounts are available for contractors qualifying multiple welders. The combined 3G/4G test in one session is more economical than two separate sessions. Call (404) 860-1288 or use our contact form for a quote.
What industries most commonly require the AWS D1.1 3G/4G qualification?
The most common industries are structural steel fabrication (buildings, industrial facilities), bridge construction (D1.5 or D1.1), shipyard and marine welding, ironworker contractors, heavy equipment manufacturing (cranes, mining equipment), and power/energy infrastructure (transmission towers, substations). Any project governed by AWS D1.1 that has groove welds in vertical or overhead positions will require all-position qualification.

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