SolidWorks BOM Automation in Practice: From 6 Parts to 600

If you design in SolidWorks, your day is probably full of the same small, repetitive jobs: numbering parts, filling in custom properties, creating drawings, exporting STEP and DWG files, and keeping BOMs honest as the design changes. None of it is hard — it is just endless. This article shows a different way to run that whole pipeline, using a real project: an assembly of six parts, spread across three subassembly levels, with multi-body weldments, a sheet-metal part, and standard fasteners. Everything you see on six parts can be repeated on 60, 600, or 6,000.

The workflow in four steps

SWTDO (SolidWorks Technical Design Optimization) treats project data as one continuous pipeline instead of a collection of disconnected files and spreadsheets:

Standardize — automatically number parts and fill their properties.
Prepare — turn weldment cut lists into real data and create drawings.
Output — batch-export STEP, DWG, and flat patterns with correct names.
Manage — run every BOM from one data library that always matches the model.

Step 1 — Automatic part numbering and property cleanup

Messy names and empty properties are the root of most downstream mistakes. In the demo, the assembly contains parts with different configurations (for example, a copper stud in two configurations (M4-10 and M4-55)), SolidWorks Toolbox fasteners, and multi-body parts. SWTDO handles all of them through the same rules.

Automatically number parts. The numbering module assigns a drawing code, name, and version to each file, following rules you define for your company. Renaming is done inside SolidWorks, not in Windows Explorer, so references stay intact — no more assemblies that open with “cannot find part” errors.
Rename with a safety net. If a file cannot be renamed, SWTDO tells you exactly which files failed and why: the file is read-only, it is open in another SolidWorks viewer, a file with the same name already exists, you lack permission to create or delete files, or a property is set as “rename-protected.” You fix the real cause instead of guessing.
Fill custom properties in bulk. One command writes material, drawing code, finish, and other properties across every sub-part of the assembly at once — consistently, with no typing by hand. Custom properties you need that are not in the standard set (for example, “production location” or a paint color) can be added with the property manager, saved, and reused.

When every part has a real code and complete properties, file names become meaningful: code + name + version. As you will see, that naming is what makes the rest of the system work.

Step 2 — Weldment cut lists and drawing creation

Multi-body weldments and sheet-metal parts are where most BOM tools fall apart, because the “part” is not the unit that gets manufactured — the bodies are. In the demo, the sheet-metal housing contains several cut-list items, and each one needs its own data.

Cut-list items become BOM rows. SWTDO reads the weldment cut list and gives every item real attributes: code, name, version, material, thickness, 3D bounding box, length, and mass. Item names can be normalized automatically to code + attribute (for example +2x18x148 for the material size), so even a file name tells you what the body is.
Statistics that are ready to use. Alongside the cut-list attribute table, SWTDO provides item-count, per-part-count, and total-attribute statistics — the kind of numbers purchasing and production ask for before you have even made a formal BOM.
Drawings created from the model. Standard three-view drawings are generated from the 3D model using your drawing templates, with options for multiple configurations at once and a no-dimension mode when you only need geometry. The same templates that create views also control your sheet formats, drafting standard, and environment checks, which keeps output consistent across the whole team.

Step 3 — Batch output of STEP, DWG, and flat patterns

When the drawing data is ready, the production files follow with one click.

Export STEP from the assembly — per configuration or per body. Instead of exporting “the part,” SWTDO exports what manufacturing actually needs. In the demo, the stud is exported once per configuration (code+M4-10, code+M4-55), and each cut-list body of the multi-body parts is exported separately (code+16x16x48, code+55x300x300). This is SolidWorks batch processing that follows your design structure instead of flattening it.
Export DWG for laser cutting and stamping. Drawings are exported to DWG with your mapping templates, including sheet-metal flat patterns — the demo shows files named code+Flat…, so the flat pattern is identifiable at a glance.
Attachments travel with the data. PDFs, images, and logo templates (for example a silkscreen logo that is not part of the assembly) can be attached to a BOM record and are exported together with the files.
Everything lands in one place. All generated files go into a single managed production library, named with the same code-based rules. One library, one source of truth.

Step 4 — A BOM that is a data library, not a spreadsheet

The final and most important idea from the demo: SWTDO’s BOM is not a static Excel table. It is a drawing-and-file management database. In the recording, six different BOMs are produced in about two minutes:

Total assembly BOM (including weldments).
Sheet-metal BOM — one sheet-metal part, but a full set of rows for every cut-list body, plus attached artwork such as the silkscreen logo template.
Purchasing BOM — automatically filtered to parts flagged “purchased,” with non-model items (a mouse, a keyboard) added as attachment-only records.
Bodies + parts BOM for multi-body work — if you buy or process the bodies before welding rather than the welded part, you can produce a BOM that lists the pre-weld bodies together with standard parts.
Subassembly BOM — with quantities counted correctly even when the same component (such as a stud) appears in several different subassembly levels.
Fastener BOM — produced by the bolt-counting module, which counts bolts from the holes in the model; no bolt bodies are required.

Three properties make these BOMs different from the tables you export by hand:

Columns are fully customizable. Roughly 70 built-in attributes can be shown or hidden with a checkbox, and you can add your own columns. Formulas are supported, including math expressions on SolidWorks 2021 and newer.
They follow the design. When the assembly changes — a part is suppressed, a quantity changes — you update the BOM and it reflects the new model. Attachments are kept, not re-entered. You never maintain “the old BOM” and “the new BOM.”
Every BOM can export its files. Because each BOM row points back to real, correctly named files in the library, exporting the purchasing BOM gives purchasing the exact STEP/DWG files they need. The code is the index head; the file names are the tail.

Why this matters for a team

No more black-hole handovers. When a designer leaves, the next person does not spend months excavating folders named by whoever created them. Files are named by rule, drawings and models live together, and a new engineer can pick up the project quickly.
A local, reliable alternative to heavy PDM. SWTDO manages files on your own folders and drives — no forced cloud, no latency. For teams that find PDM or 3DEXPERIENCE too heavy, it works as a lightweight local data-management layer; an enterprise PDM edition is also available.
Purchasing, QC, and assembly can get files themselves. SWTDO is designed as a client for more than the CAD designer: with the right permission, a purchasing or QC user can open the product library and export the drawings they need — without opening SolidWorks.

Frequently asked questions

Does SWTDO handle multi-configuration and multi-body parts? Yes. Multi-configuration parts (such as the M4-10 / M4-55 stud) and multi-body weldments and sheet-metal parts are first-class in the workflow. You choose whether to output per part, per body, or per sheet-metal body, and whether you need only the bodies or the bodies plus the post-weld part.

Can I count bolts without adding them to the model? The bolt-counting module counts fasteners from the holes in the model geometry — the demo BOM was built even though the assembly contained no bolt bodies. Toolbox and other standard parts are also recognized and reported.

Can I add my own BOM columns? Yes. Around 70 attributes are built in, and you can add custom columns for anything your company tracks (production location, cost, supplier…). Columns and values can be saved and reused, and editable columns can be written back to the model.

Do I need to write macros? No. SWTDO is a no-code tool. Repetitive jobs are configured once through its batch frameworks, then run from buttons inside SolidWorks.

Is SWTDO a PDM? It is a local data-and-file management system built around your SolidWorks project folders: it standardizes naming and properties, generates drawings and production files, and manages BOMs as live data. It can complement a PDM, or serve as a lighter alternative; an enterprise edition adds PDM-style check-in/check-out and network features.

Can non-designers use it? For viewing and exporting, yes. Purchasing, QC, and assembly users can be given permission to open the library and export files without owning SolidWorks.

Watch the full demo: the 6-part project, end to end

The four episodes below walk the same six-part assembly through the complete SWTDO workflow — automatic numbering and properties, weldment cut lists and drawings, batch STEP/DWG export, and finally the BOM as a live data library.

This article is based on the SWTDO demo series “Managing a 6-Part SolidWorks Project,” recorded in SolidWorks 2026. Watch the full demo video, or download the free trial and run the same workflow on your own assembly.

Ready to replace manual BOMs and one-by-one exports? Download the SWTDO free trial, or contact sales for an enterprise demo.