Automating SolidWorks drawing packages with VBA and Python over COM

During my time as an Automation Engineer at Argos, an oil and gas automation company in Mexico, I noticed the engineering department was losing hours on a purely mechanical task: many SolidWorks parts had to be turned into 2D drawings, and every .slddrw file then had to be converted to PDF one by one. Slow, tedious and inefficient.

Finding the seam: the COM interface

Using Claude and the SolidWorks documentation, I discovered the whole workflow could be automated with VBA and Python scripts through the COM interface: generating the 2D drawings, dimensioning the part, inserting its data, generating tables such as the bill of materials, and the rest of the routine steps a drawing requires. Drawing packages for entire assemblies that used to take hours were now done in minutes.

From .slddrw to a print-ready catalogue

To close the loop, I wrote a Python COM script that automatically converted every .slddrw file to print-ready A3 and A4 PDFs, ready for the department’s physical catalogue. With this the whole engineering department’s workflow got noticeably more fluid and efficient.

Takeaway

None of this needed a plugin, a license upgrade or vendor support. SolidWorks already exposes everything a drawing requires through COM — the hours were going into clicking through steps that were documented all along. It is the same lesson as the US$25,000 motor driver from the same job: somewhere underneath there is an API you can script.