Automation

Every SolidWorks API developer has spent hours debugging a macro that produces no error, no exception, and completely wrong output. The SolidWorks COM API is old enough that many of its failure modes predate modern error handling conventions — methods that silently return Nothing, boolean flags that are ignored, and side effects that modify document state without warning. This is a catalogue of the seven most common ones. Each has a pattern, a root cause, and a fix. ...

If your shop uses SolidWorks and your supplier’s shop uses Inventor, at some point you will end up comparing notes on batch DXF export. Both platforms flatten sheet metal and write DXF files. Both can be automated. The workflows look similar from a distance and differ substantially in the details that matter for production pipelines. This is a comparison of the actual automation approaches, not marketing specs. Platform capabilities are drawn from the COM API (SolidWorks) and the ObjectModel/iLogic API (Inventor). ...

The SolidWorks API speaks one language for lengths: meters. Not millimeters. Not inches. Meters, always, regardless of what your document’s unit system displays. This sounds like something you’d learn in the first chapter of any SolidWorks API tutorial, and it is — yet it causes more silent macro failures than any other single issue. The problem is not that developers don’t know about it. The problem is that it bites you in a second way you didn’t expect, in a context you were already confident about. ...

A SolidWorks macro gets you 80 percent of the way there. It can open files, traverse assemblies, read custom properties, save DXF, and close — all without writing a line of C#. The VBA IDE ships inside SolidWorks, the API reference is documented, and a working batch export macro can be running in an afternoon. Then the macro breaks in a way that a one-line fix will not solve. Or someone needs it on fifteen workstations, or the team wants a toolbar button, or the workflow needs to respond to file saves without being manually invoked. That is when engineers discover that “just adding a button” requires a complete architectural shift. Macros and add-ins are not on the same continuum — they differ at the design level, and the capabilities that matter most to production workflows sit entirely on the add-in side of that line. ...

You spend ten minutes configuring the DXF export dialog — turning on bend lines, setting the layer map, choosing which sketch entities to include. You close SolidWorks. You open it the next morning and every checkbox is back to the default. Again. This is one of the most reliably frustrating behaviors in SolidWorks, and it has a specific technical reason that most documentation skips over. More importantly, there are three concrete fixes — ranging from a template trick to a four-line API call — that eliminate the problem entirely. ...

SolidWorks 2026 ships with AutoGenerate Drawing — an AI feature that takes a 3D model and produces a dimensioned 2D drawing with views, annotations, and BOM in the background while you keep working. LinkedIn posts about AI-generated macros and SolidWorks MCP servers are getting traction. The question is a reasonable one: if AI can generate drawings and answer questions about your model in natural language, what’s left for automation tools to do? ...

The thread A post in r/gis hit 101 upvotes this spring after a demo showed Claude performing CAD-adjacent spatial tasks. The 96 comments divided into three camps: alarm (entry-level GIS is gone), pragmatism (analysts who use AI will outcompete those who don’t), and dismissal (spatial analytics requires domain knowledge that LLMs don’t have). All three positions contain something true. The useful question is not “will AI replace GIS analysts?” — that framing produces either denial or panic, neither of which helps. The useful question is: which specific tasks are genuinely automatable, and what does that mean for how you spend your time? ...

A user on r/SolidWorks described building a car-configurator-style model. A global variable NumSlots drove both the count of a linear sketch pattern and a sweep feature that read the slot spacing. After dragging the configuration slider, the sweep updated. The sketch pattern did not. Opening the sketch, closing it without touching anything, then rebuilding — slot count finally snapped to the new value. This is not a bug report. It is a predictable consequence of how SolidWorks schedules equation evaluation during a model rebuild. Once you understand that schedule, you stop designing models that depend on the wrong evaluation order and start structuring equations so they survive a Ctrl+B. ...

To export a SolidWorks BOM to Excel, you have three paths — and choosing the wrong one is how you end up maintaining a 200-line macro for two months before admitting it doesn’t quite work. A post on r/SolidWorks showed exactly that: a macro that exported an assembly BOM to Excel with description, material, length, thickness, quantity, and supplier data. It mostly worked. Six comments later, nobody had a better answer than “looks fine to me.” The approach was fine — the architecture was wrong. ...

Every few weeks a mold shop posts a job for a Python or C# developer who can automate their SolidWorks mold design pipeline. The scope is usually the same: take an incoming 3D model, run shrinkage, generate parting surfaces, split the core and cavity, and hand off tooling data. The assumption is that because SolidWorks has a documented API, every mold step is scriptable. It isn’t. Some steps map cleanly to IFeatureManager calls. Others still require a human to pick faces in the graphics area. Knowing which is which is the difference between a pipeline that ships and one that spends six months bouncing between the add-in and the user. ...