Weld SymbolGames
GUIDE 20 OF 30 · Supplementary Symbols · intermediate

Weld Contour and Finish Symbols

Contour symbols specify the required finished weld surface. Under AWS A2.4:2020 terminology, a straight contour is flat for a fillet weld and flush for groove, plug, slot, and other applicable welds; convex and concave retain their usual names.

After this guide, you can:
  • Separate weld contour from weld type
  • Recognize flush, convex, and concave profile requirements
  • Read the finish letter as a method—not a quality grade
Run the release checkTest yourself
ANNOTATED PRINTFillet weld · flat contour · G finish
Weld Contour and Finish Symbols annotated blueprint callout
The fillet weld requires the specified flat contour, with grinding identified as the finishing method. The complete drawing and applicable acceptance requirements control allowable material removal.
WHY THIS MATTERS IN VISIBLE HANDRAIL · PROFILE ACCEPTANCE

Reading contour as weld type

Contour and finishing can affect clearance, fatigue behavior, coating, appearance, and cost. Unnecessary grinding or the wrong profile can remove useful weld metal or damage base material.

VISIBLE HANDRAIL · PROFILE ACCEPTANCE

A fillet weld requires a flat contour with G

01 · What is on the sheet

The base triangle defines the fillet weld, while the straight contour mark and finish-method letter modify its final surface.

02 · The decision

Read the contour as flat for this fillet weld and G as the designated grinding method. Confirm allowable removal, weld size, and acceptance criteria before finishing.

03 · The consequence

The 2020 flat-versus-flush terminology is preserved and the finish instruction is not mistaken for GMAW or weld size.

DRAWING EVIDENCE

Read weld, contour, and finish as three instructions

Begin with the cue in the first column. The final column records the drawing, detail, procedure, or acceptance question that this callout cannot answer by itself.

Visual cueWhat it establishesWhat still needs verification
Straight contour markFlush/flat final profile requirementAcceptance tolerance comes from the governing requirement.
Curved contour markConvex or concave profile according to orientationRead it relative to the base weld symbol.
Finish letterSpecified method used to obtain the contourIt is not the weld process or a surface-quality score.
FIELD TRANSFER WORKSHOP

Separate the required shape from the method used to obtain it.

A visible handrail connection specifies a flat fillet-weld contour and G as the finishing method. The inspection note must not turn grinding into the weld type.

01

Use flat for this fillet-weld contour; reserve flush terminology for other applicable welds.

02

Treat G as grinding, not as a groove or process designation.

03

Do not assume a missing finishing letter means welding-only under A2.4:2020.

VISIBLE HANDRAIL · PROFILE ACCEPTANCEA three-part profile inspection note: weld, contour, finishing method
Visible handrail fillet weld with separate flat-contour and grinding designations
This training sheet is separate from the annotated example above. Verify its callout against the governing drawing, WPS, and project requirements before production use.
MARKUP TO HAND IN

Annotate the base weld, flat contour mark, and G finish letter separately. Then write what can and cannot be accepted from the finished surface alone.

Deliverable · A three-part profile inspection note: weld, contour, finishing method
Compare with the field read +

The callout requires the indicated fillet weld, a flat final contour, and grinding as the stated finishing method. Acceptance still depends on the complete drawing and applicable criteria.

WORKING METHOD

Inspect the final profile without losing the base weld

First read the elementary weld symbol, then find the contour mark adjacent to it and any finish-method letter associated with the contour requirement.

  1. Identify the weld type and applicable side first.
  2. Use flat for a fillet weld or flush for another applicable weld when the straight contour symbol is shown.
  3. Read any finish-method letter attached to the contour mark.
  4. Check the drawing notes for surface tolerance and acceptance criteria.
Weld Contour and Finish Symbols joint and weld concept diagram
Contour describes the required result; the finish letter describes a method. Neither replaces weld size, acceptance criteria, or the governing procedure.
DECIDING DISTINCTIONS

Flat, flush, convex, and concave belong to different contexts

Contour

The required final weld profile

Evidence to useWhat shape must remain?

Finish

The method used to obtain that profile

Evidence to useHow is the profile achieved?

Weld type

The underlying fillet, groove, or other weld

Evidence to useIdentify it before reading modifiers.
FAILURE CHECKS

Finish letters that get mistaken for weld processes

01

Reading contour as weld type

The contour mark modifies a fillet, groove, or other weld; it does not identify the elementary weld.

02

Assuming a process letter

A finish letter beside a contour is not automatically the welding process shown in the tail.

03

Over-finishing

Do not infer a smoother or lower profile than the drawing and acceptance requirements specify.

RELEASE GATE

Can the final profile be accepted without inventing a method?

Use the full list before fabrication, fit-up, or inspection. This is a drawing-reading handoff—not a substitute for the governing acceptance standard.

  1. 01Identify the base weld
  2. 02Read required contour
  3. 03Read finish method
  4. 04Find tolerance/acceptance criteria
  5. 05Protect required weld and base-metal dimensions
Questions learners ask

Contour & Finish FAQ

When is the straight contour called flat or flush?

AWS A2.4:2020 uses flat with fillet welds and flush with other applicable welds such as groove, plug, and slot welds.

What does G commonly mean beside a contour?

In the illustrated AWS-style finish-method convention, G indicates grinding.

What if a contour symbol has no mechanical finish method?

AWS A2.4:2020 no longer means welding-only. The required contour may be obtained by a method selected for the work unless another requirement controls it.

Does a straight contour allow unlimited material removal?

No. The applicable drawing, weld-size tolerance, code, and acceptance criteria still control the finished condition.

REFERENCE SCOPE

Evidence and limits for this Contour & Finish lesson

This guide teaches common AWS-style drawing interpretation. It is educational material, not a substitute for the purchased standard, project specification, code, WPS, or qualified engineering direction.

EDITORIAL CHECKSource locators, image labels, worked example, and question logic checked; no independent technical sign-off is currently publishedLast substantive editorial review: July 18, 2026
TOPIC LOCATORS IN AWS A2.4:2020AWS A2.4:2020 §6.13AWS A2.4:2020 §§7.6, 8.6, 9.7, 10.9, 11.6, and 12.7Locators help readers find the topic in a purchased copy; they are not a reproduction or official interpretation of the standard.
AWS A2.4:2020 · 8th EditionStandard Symbols for Welding, Brazing, and Nondestructive Examination ↗Miller Welding BasicsIndependent educational cross-check for common symbol families ↗

How this page was made. The training diagrams, worked example, comparisons, and questions are original educational material. Read the editorial and technical review policy for the full process.

FINISHED READING?

Save your place after Contour & Finish.

This marker records reading progress only; it does not mean the topic is mastered. Use the six-question practice page to check your understanding.

Next: Projection Weld →
CONTINUE EXPLORING
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Educational practice only. Verify production work against the governing drawing, applicable standard, WPS, and qualified instruction.