Weldments: Structural Members, Trim/Extend, and Weld Bead Annotations

Weldments in SolidWorks: Building Structural Frames

The SolidWorks Weldments environment lets you design welded structural assemblies — such as marine davit frames, equipment skids, and crane booms — entirely inside a single part file. Instead of creating individual assembly components for every tube or beam, you sketch a skeleton of lines and then apply standard profiles to those lines. SolidWorks treats each resulting member as a separate body, tracks its length in a cut list, and carries that data directly into your drawing. This workflow mirrors real fabrication shop practice and is a tested skill on the CSWA exam.

Starting with a 3D Sketch

A weldment begins with a 3D sketch that defines the centerlines of all structural members. Open a new part, enable the Weldments toolbar, then go to Insert > Weldments > 3D Sketch. Draw lines in multiple planes to represent every member of the frame. Fully define the sketch with dimensions and relations — underdefined geometry causes unpredictable member lengths in the cut list. For a davit frame, a typical skeleton includes vertical uprights, horizontal outreach arms, diagonal braces, and a base spreader.

Applying Structural Members

With the 3D sketch complete, select Insert > Weldments > Structural Member. In the Property Manager you choose:

• Standard — such as ANSI
• Type — such as rectangular tube
• Size — such as 3×2×0.25 in.

Click the sketch lines that share the same profile and orientation in one group. Add a second group for members oriented differently. SolidWorks sweeps the chosen cross-section along each line and creates a separate solid body per member. The profile library is stored in the SolidWorks installation folder; if a size is missing, your instructor can supply a custom profile.

Trim/Extend: Cleaning Up Joints

Raw structural members overlap or leave gaps at corners. Use Insert > Weldments > Trim/Extend to fix this. Select the members to trim (the "bodies to be trimmed") and the member or face that acts as the trimming boundary. The Corner Treatment options — Butt1, Butt2, and Miter — control how ends meet:

• Butt1/Butt2 — one member runs full length; the other is cut square against it.
• Miter — both members are cut at 45° so faces meet in a V.

After each Trim/Extend operation, open the Cut List folder in the Feature Manager tree. SolidWorks automatically recalculates body lengths. Verify that lengths match your shop ticket before moving on — a wrong trim can shorten a member by the full wall thickness and cause a fitment failure in the shop.

Gusset Plates

A gusset is a flat plate added at a joint to increase load capacity. In SolidWorks, select Insert > Weldments > Gusset and pick the two planar faces that meet at the joint. Set the thickness, profile shape (triangular or polygonal), and offset. The gusset is added as another body in the cut list and will appear as a separate line item in the drawing table. For a davit frame, place gussets at the main outreach–upright joint where bending loads are highest.

Weld Bead Features

Select Insert > Weldments > Weld Bead to add a cosmetic or smart weld bead at each joint. Pick the face of one member and the face or edge of the adjoining member. Entering a bead size creates a visual representation and stores weld data. Although the weld bead feature is not a structural simulation tool, it ties weld information to the model for documentation purposes.

Drawing Documentation with AWS Weld Symbols

Once the weldment model is complete, create a drawing and insert at least one model view. Then:

1. Go to Insert > Tables > Weldment Cut List to place the cut list table. It shows body description, profile size, quantity, and length automatically.

2. Use Insert > Annotations > Weld Symbol to place AWS A2.4-compliant weld symbols on the drawing. A fillet weld symbol requires: the fillet weld symbol (triangle leg), weld size to the left of the symbol, and optionally length and pitch (length–pitch format: length-pitch). Place the symbol on the reference line with the arrow pointing to the joint.

AWS A2.4 governs the graphical symbols for welding, brazing, and nondestructive examination. The arrow side of the weld symbol always points toward the viewer's side of the joint; the other side is noted above the reference line. Always check weld symbols against the AWS reference chart provided in lab before submitting your drawing.

Shop Safety in the Weldment Lab

This is a CAD lab session, but weldment drawings go directly to fabrication shops where serious hazards exist. As a future drafter:

• Dimension weld sizes accurately. Undersized welds on a davit frame can fail under load, creating a crushing or falling-load hazard.
• Label materials clearly; substituting a lower-grade steel changes allowable stress.
• If you ever visit the fabrication floor to verify a drawing, wear safety glasses, hearing protection, and leather gloves minimum; a welding shield is required near any arc.
• Lockout/tagout (LOTO) procedures apply to all machinery on the shop floor. Never touch equipment unless it has been locked out by a qualified person.

Cut List Accuracy Check

Before submitting, compare every length in the SolidWorks cut list table against the instructor-prepared shop ticket. Tolerance is ±1/8 in. (approximately ±3 mm). Errors outside tolerance must be corrected in the model — never edited manually in the table — so the model remains the single source of truth.