Fillet Gauge / Guides and tools
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Exam facts and requirements
58 resourcesWhat is on the exam, who can sit it, what it costs and how to keep it.
- CWI Part C on D1.5: the bridge code examThe D1.5 bridge code exam for CWI Part C or the endorsement: 50 questions in 120 minutes, open book, the five content areas, fees and a free check.
- CWI Part C on API 1104: the pipeline examThe API 1104 code exam for CWI Part C or the endorsement: 135 minutes, open book with the 22nd edition, the five content areas, fees and a free check.
- ICC S1 Structural Steel and Bolting exam: modules and domainsICC's S1 Structural Steel and Bolting Special Inspector exams: the three modules, S1C's 60 questions in 2 hours, the four outline domains and a free check.
- WPQ2 endorsement exam: format and outlineThe AWS Welding Procedure Qualifier (WPQ2) endorsement for CWIs and SCWIs: 55 questions in 180 minutes, D1.1 and B2.1 on screen, the three areas and fees.
- CWI Part A practice test: 165 questions, closed book, 10 domainsCWI Part A practice test guide: 165 closed-book questions in 135 minutes, where the points are, 3 sample questions, and exam day step by step.
- CWI Part B practice test: replicas, tool kit and a timed planCWI Part B practice test guide: 46 questions in 120 minutes, the replicas, the tool kit, the Book of Specifications, three practice items and a timed plan.
- CWI testing centers and locations: where to take Parts A, B and CFind a CWI testing center near you: Part B at AWS-approved test sites on event dates, Parts A and C at Prometric centers, and the order to book them in.
- What the CWI exam costs in 2026: fees, retests and seminarsThe CWI exam costs $1,255 for AWS members and $1,520 for non-members. See seminar packages, retest fees and how to budget for one attempt.
- CWI retest rules: which parts, how many times, and what AWS asks forFailed a CWI part? Which parts you retake, how many retests you get, the Part C code rule, and the training AWS wants before your second retest.
- AWS CWI renewal at years 3 and 6 and 9-year recertification: routes and feesAWS CWI renewal step by step: years 3 and 6, the 9-year recertification routes (Part B, endorsement, 80 PDHs, course), the window and 2026 fees.
- CWI prep for fabricators and inspection firmsPlan CWI exam preparation for a crew. See what each seat includes, the per-seat crew prices and how quotes and invoices work.
- How to become a certified welding inspector: CWI certification stepsHow to become a certified welding inspector: AWS CWI requirements by education, the three exam parts, how long it takes and the 2026 fees, step by step.
- The AWS CWI exam: three parts, format, scoring and feesThe AWS CWI exam in one page: what Parts A, B and C test, question counts and time limits, the 72% rule, 2026 fees, where you sit each part and retests.
- CWI exam pass rate: what AWS publishes and every estimate checkedAWS publishes no CWI pass rate. Here's what it does publish, the 72% rules, question counts and time per part, and how to use them to prep smarter.
- Free CWI practice resources: ours and AWS'sEvery free CWI practice resource in one place: our 10-question checks, flashcards, quizzes and drills, plus the free AWS PDFs, each with a link.
- CWI Part B tool kit checklist (printable)A printable CWI Part B tool kit checklist: every tool AWS supplies, what you bring, how to practice each tool, and a pre-exam checklist to tick off.
- CWI Part A formula sheet (printable)Printable CWI Part A formula sheet: heat input, IIW carbon equivalent, tensile stress, elongation, reduction of area, units and fillet throat, each worked.
- Butt joint: meaning and how to check itWhat a butt joint is, how to tell it from a T or corner joint, which groove preps it takes, and where butt joints show up on all three CWI exam parts.
- T-joint: meaning and how to check itWhat a T-joint is, how to spot one on a part or a sketch, which welds it takes (fillet, groove or both) and where T-joints come up on the CWI exams.
- Corner joint: meaning and how to check itWhat a corner joint is, open versus closed corners, how to tell a corner from a T-joint or an edge joint, and where corner joints appear on the CWI exams.
- Lap joint: meaning and how to check itWhat a lap joint is, why it's fillet welded at the edges, which other welds suit an overlap, and how lap joints show up on CWI Parts A, B and C.
- Edge joint: meaning and how to check itWhat an edge joint is, square versus flanged edges, why it's mostly a sheet metal joint, and how to tell it from corner and butt joints on the CWI exam.
- Weld face: meaning and how to check itWhat the weld face is on a groove and a fillet weld, how it differs from the root surface, what you check on it, and where it shows up on the CWI exams.
- Weld root: meaning and how to check itWhat the weld root is, how it differs from the root of the joint, where the root sits on groove and fillet welds, and why it matters on the CWI exams.
- Weld toe: meaning and how to check itWhat a weld toe is on groove and fillet welds, how to find it, why undercut, overlap and fatigue cracks start there, and how it shows up on the CWI exams.
- Fillet weld leg: meaning and how to check itWhat a fillet weld leg is, how it differs from fillet size, how to measure equal and unequal legs with a fillet gauge, and where legs show up for CWIs.
- Actual throat: meaning and how to check itThe actual throat of a fillet weld: what it measures, why convexity inflates it, and how it differs from the effective and theoretical throats.
- Effective throat: meaning and how to check itWhat the effective throat of a fillet weld is, why convexity is left out, how root fusion fits in, and how it differs from the other two throats.
- Theoretical throat: meaning and how to check itThe theoretical throat of a fillet weld: where the 0.707 factor comes from, how a concave face changes it, and how it differs from the other throats.
- Weld reinforcement: meaning and how to check itWhat weld reinforcement is on a groove weld, face versus root reinforcement, how to measure its height, and why more of it isn't stronger.
- Root opening: meaning and how to check itWhat root opening means in a groove joint, how to measure the gap before welding, how it differs from root face, and where it shows up on the CWI exams.
- Root face: meaning and how to check itWhat a root face, or land, is on a beveled joint, why welders leave one, how to tell it from root opening, and where the term shows up on the CWI exams.
- Bevel angle vs groove angle: meaning and how to check itBevel angle versus groove angle: what each measures, why a single-V doubles the bevel, where the angle sits on a symbol and how to check it.
- Weld backing: meaning and how to check itWhat backing is in welding, permanent versus removed backing, how it differs from a backing weld or backing gas, and where it shows up for CWIs.
- Heat-affected zone: meaning and how to check itWhat the heat-affected zone is, why its properties change, how preheat and heat input affect it, and where the HAZ shows up on the CWI exams.
- Weld pass vs weld layer: meaning and how to check itWeld pass versus weld layer: one trip along the joint versus one level of the weld, with root, fill and cap passes explained for CWI candidates.
- Interpass temperature: meaning and how to check itWhat interpass temperature is, how it differs from preheat, why a procedure can set a minimum and a maximum, and how inspectors check it.
- Welding terms glossary: joints, weld parts and symbolsWelding terms glossary in plain English: joint types, weld parts, fillet throats, fit-up, heat terms and every welding symbol, each with a drawing.
- Weld porosity: what it is and how to spot itWhat weld porosity is, how scattered, cluster, elongated and piping pores look, how to measure a pore on a replica and what it gets confused with.
- Slag inclusion: what it is and how to spot itWhat a slag inclusion is, why it sits between passes or against the sidewall, how it looks on a radiograph and how to tell it from porosity.
- Tungsten inclusion: what it is and how to spot itWhat a tungsten inclusion is, why it only comes from GTAW, why it shows bright on a radiograph while porosity shows dark, and how to prevent it.
- Incomplete fusion: what it is and how to spot itWhat incomplete fusion is, where it hides on the sidewall and between passes, which NDE method finds it and how to tell it from incomplete penetration.
- Incomplete joint penetration: what it is and how to spot itWhat incomplete joint penetration is, how it looks from the root side and on film, why it forms and how to tell it from incomplete fusion on CWI Part B.
- Weld undercut: what it is and how to spot itWhat weld undercut is, how to find it at the toe, how to measure its depth with a gauge on a Part B replica, and how to tell it from underfill and overlap.
- Weld overlap: what it is and how to spot itWhat weld overlap is, why the lip of unfused metal at the toe hides a notch, how to confirm it and how to tell overlap from undercut and convexity.
- Weld underfill: what it is and how to spot itWhat weld underfill is, how to see a groove weld face sitting below the plate, how to measure it and why it is so often confused with undercut.
- Longitudinal weld crack: what it is and how to spot itWhat a longitudinal crack is, why centerline cracks form in deep narrow beads, how to find one with visual, PT or MT, and what it gets mistaken for.
- Transverse weld crack: what it is and how to spot itWhat a transverse crack is, why cracks form across a weld, how they reach into the base metal, how they are found and how to tell them from other lines.
- Crater crack: what it is and how to spot itWhat a crater crack is, why an unfilled crater at the end of a bead cracks, how the star shape looks, and how welders and inspectors prevent and find it.
- Toe crack: what it is and how to spot itWhat a toe crack is, why cracks start where the weld face meets the plate, how to tell one from undercut or a shadow, and how to confirm it.
- Root crack: what it is and how to spot itWhat a root crack is, why the root of a groove or fillet weld cracks, how to find one with NDE, and how to tell it from lack of penetration.
- Underbead crack: what it is and how to spot itWhat an underbead crack is, the three conditions behind hydrogen cracking, why it can show up hours later, and how preheat helps prevent it.
- Lamination in steel plate: what it is and how to spot itWhat a lamination is, why it comes from the steel mill and not the weld, how it shows on a cut edge or bevel, and why straight-beam UT finds it.
- Lamellar tearing: what it is and how to spot itWhat lamellar tearing is, why step-like cracks form under welds on thick rolled plate, how to prevent it and how it differs from lamination.
- Arc strike: what it is and how to spot itWhat an arc strike is, why a tiny melted spot on the base metal outside the weld can crack, how to find one and why it is not spatter or porosity.
- Weld spatter: what it is and how to spot itWhat weld spatter is, why droplets fly from the arc, when spatter is only cosmetic and when it matters, and how to tell it from porosity and arc strikes.
- Excessive weld reinforcement: what it is and how to spot itWhat excessive reinforcement on groove welds and convexity on fillets mean, how to measure each with a gauge and why more weld metal isn't better.
- Burn-through: what it is and how to spot itWhat burn-through is, how a hole melted through the root looks from the face and the back, why too much heat at the root causes it, and how to avoid it.
Study guides
31 resourcesWork through one topic at a time, with the method and worked examples.
- CWI Part C practice test and D1.1 exam guideFree CWI Part C practice for D1.1:2025: clause-finding drills, how the on-screen code works with no word search, and a free 10-question check.
- Welding symbols on drawings: how to read themRead any welding symbol in 5 steps: arrow or other side, fillet and groove, all-around, field weld and stitch notation, with worked examples.
- Welding symbols chart: what every part of the symbol meansWelding symbols chart with meanings: every basic weld symbol and supplementary mark on blueprints, where each dimension goes, and a printable PDF view.
- NDE methods on Part A: which method finds which discontinuityCWI Part A NDE explained: what PT, MT, RT and UT can and cannot find, how to choose a method for a flaw and joint, and how to practice it free.
- CWI training, courses and online classes comparedCWI training compared: AWS seminars, live online classes, self-paced courses, books and practice banks, priced from each seller's page on 25 Oct 2026.
- D1.1 code book for CWI Part C: which edition to buyWhich D1.1 code book to buy for CWI Part C: why 2026 exams use the 2025 edition, not 2015 or 2020, where to buy it, and how to tab and drill it.
- CWI study guide: what to learn for each part, in orderA CWI study guide for Parts A, B and C: what to learn in each part, the order to study it, and every free guide, tool and drill to use along the way.
- D1.1 visual inspection acceptance criteria, explainedWhat each D1.1 visual acceptance criterion covers, and how to find and read the governing Clause 8 table fast on CWI Part C.
- CWI Part B measurement workflowPractice a CWI Part B workflow: identify the measurement, check the gauge, record units, find the specification and document the decision.
- CWI Part C D1.1 navigation workflowBuild a Part C lookup routine: classify the task, choose the D1.1 clause, check its scope and notes, then record the answer's reference.
- Fillet weld symbol: what it means on a drawingWhat the fillet weld triangle means on a drawing: which side gets the weld, where the size and length go, and how to read 1/4 and 2-6 correctly.
- Weld all around symbol: what it means on a drawingWhat the circle where the arrow meets the reference line means, how to read it with a fillet or a flag, and the mix-ups that cost points on drawings.
- Field weld symbol: what it means on a drawingThe flag on a welding symbol means the weld is made at the job site. How to read it, how it combines with weld all around, and what it changes.
- Stitch weld symbol: what it means on a drawingHow a stitch (intermittent) weld shows on a welding symbol, what 3-10 means, how to work out the gap, and how chain and staggered stitches differ.
- V-groove weld symbol: what it means on a drawingWhat the V-groove weld symbol means, where groove depth, weld size, root opening and groove angle sit, and how to tell a V from a bevel at a glance.
- Bevel groove weld symbol: what it means on a drawingWhat the bevel groove weld symbol means, how the break in the arrow picks the member to bevel, and where the angle and root opening go.
- Plug and slot weld symbol: what it means on a drawingWhat the rectangle on a welding symbol means, how plug and slot welds differ, which member has the hole, and where size, depth and pitch go.
- Spot weld symbol: what it means on a drawingWhat the spot weld circle means on a drawing, where size, pitch and the number of welds go, and how not to confuse it with weld all around or seam.
- Back weld and backing weld symbol: what it means on a drawingBack and backing welds share one open half-circle opposite the groove. How to read it, which goes first, and how it differs from melt-through.
- Weld contour symbol: what it means on a drawingWhat the flat, convex and concave contour marks mean on a welding symbol, how finish letters such as G and M work, and how they differ from code limits.
- Square groove weld symbol: what it means on a drawingWhat the square groove weld symbol means, where the root opening and weld size go, and how to tell two parallel strokes from an edge weld mark.
- U-groove weld symbol: what it means on a drawingWhat the U-groove weld symbol means, where groove depth and weld size go, and why the groove radius and root face come from a detail in the tail.
- J-groove weld symbol: what it means on a drawingWhat the J-groove weld symbol means, how the break in the arrow picks the member to prepare, and where groove depth, radius and root face come from.
- Flare-V groove weld symbol: what it means on a drawingWhat the flare-V groove weld symbol means, which joints it fits, where the depth and the weld size in parentheses go, and how not to read it as a U.
- Flare-bevel groove weld symbol: what it means on a drawingWhat the flare-bevel groove weld symbol means, the tube, bar and sheet joints it fits, where the weld size goes, and how it differs from a bevel mark.
- Edge weld symbol: what it means on a drawingWhat the edge weld symbol means on a drawing, which joints take it, why its size is depth of fusion and not bead width, and how to spot it beside grooves.
- Surfacing weld symbol: what it means on a drawingWhat the surfacing weld symbol means, why it only goes on the arrow side, where the buildup thickness goes, and how the area and layers are given.
- Seam weld symbol: what it means on a drawingWhat the seam weld symbol means, where width, length and pitch go, why it usually sits centered on the line, and how to tell it from a spot weld.
- Melt-through symbol: what it means on a drawingWhat the melt-through symbol means, where the reinforcement height goes, and how a filled half-circle differs from a back weld, backing weld or backing.
- Double-V groove weld symbol: what it means on a drawingWhat a V on both sides of the reference line means, why each side carries its own depth and angle, and what a blank side or a spacer tells you.
- Types of weld discontinuities: what each one looks likeEvery common weld discontinuity in one table: where it sits, the one tell that names it, and a full page with an original drawing for each of the 20 types.
Practice tests and drills
10 resourcesCheck yourself on questions, symbols and code look-ups, then see what to fix.
- Welding symbols quiz: read the symbol, name the weldName the weld from its symbol, with a free chart to print.
- CWI code navigation drill: find the clause on a clock (Book of Specifications and D1.1)Find D1.1 clauses on a clock and build Part C speed.
- Weld gauge reading trainer: fillet gauge and V-WAC practicePractice reading a V-WAC gauge and a fillet gauge until it is automatic.
- CWI Part B practice: gauge readings and replica callsRead a Hi-Lo gauge, a V-WAC and a fillet weld, name the mark on a replica, then make the call against a practice spec.
- Weld discontinuities quiz: name the defectName porosity, undercut, overlap and 10 more from drawings, with the tell for each look-alike.
- Welding process quiz: SMAW, GMAW, GTAW, SAWName 7 welding processes and 4 GMAW transfer modes from drawings, then match shielding, polarity and flaws.
- Weld position trainer: 1G to 6G and 1F to 4F drillsName 1G to 6G and 1F to 4F from original drawings, or pick the drawing for a code, with the geometry explained.
- NDE methods quiz for CWI: PT, MT, RT, UTMatch VT, PT, MT, RT, UT and ET to the flaw and the material, with the reason each wrong method fails.
- WPS and PQR review drill for CWI Part CCheck 13 invented WPS, PQR and WPQ sets and catch the entry that is out of range.
- Free CWI practice test for Parts A, B and CFree CWI practice test for Parts A, B and C. Try one explained question per part, see how each part is tested, then take the free 10-question check.
Tools and calculators
10 resourcesRun the math your exam asks for and get the answer in seconds.
- CWI seminar and exam dates by city, 2026-27Find a CWI exam date and city to aim for.
- CWI eligibility checker: do I qualify for CWI or CAWI?Find out in a minute whether you qualify for CWI or CAWI.
- CWI exam cost calculator: initial fees, retests and the 72% ruleTotal your CWI exam cost, cost per part and what a retest adds.
- Welding symbol builder: draw a symbol and read itDraw a welding symbol and read back what it calls for.
- Fillet weld calculator: leg, throat, area and weld metal weightLeg to throat, volume and weight for one weld or a whole joint list.
- Carbon equivalent calculator: IIW CE and Pcm for welding steelGet IIW carbon equivalent and Pcm from a heat analysis, step by step.
- CWI math calculator: heat input, carbon equivalent, tensileHeat input, carbon equivalent and tensile math in seconds.
- Heat input calculator: kJ/in and kJ/mmVolts, amps and travel speed to heat input in kJ/in and kJ/mm.
- CWI study plan builder: week-by-week scheduleA week-by-week CWI plan for Parts A, B and C from your exam dates and hours.
- Free CWI Part A flashcards: 77 cardsFlip original cards on processes, symbols, NDE, discontinuities and formulas, and track what you know.