Theia turns 2D drawings into validated 3D CAD files

A 2D engineering drawing goes into Spare Parts 3D’s Theia; later, a 3D STEP file comes back. Behind the upload is a division of labor: AI extracts geometry and recognizes patterns, while engineers check the dimensions and features before the file is returned. Hugo Manning, lead product manager for Theia, described the service to Engineering.com as a way to make the output “fully validated.”

The basic idea is spreading across design software. Dassault Systèmes has announced that Leo can turn PDF drawings into 3D models in xDesign, while Ortho2CAD and gNucleus AI also generate CAD models from drawings. Theia’s distinction, according to Manning, is not that AI creates the model, but that a human engineer validates it rather than leaving the customer with an unchecked result.

That safeguard also sets the pace and the price. Theia automatically assesses complexity using factors such as the number of dimensions, views and geometric features. The quoted price ranges from €9 to €200 per drawing, with a basic monthly plan providing 100 credits for €100. The service is therefore not instantaneous: Manning says about 75% of parts are returned within a day.

So what changes in practice? An engineer or spare-parts team can start from an existing 2D drawing and request a usable 3D model without treating an AI-generated file as final by default. Theia handles the repetitive extraction work, while an engineer remains responsible for checking the details that matter. The sources do not quantify how much time a customer saves.

The trade-off is explicit. Manning says Theia will take longer, and perhaps cost more, than an unchecked AI tool in exchange for higher quality. The service lets users upload drawings and receive files, but its delivery time and cost vary with each drawing’s complexity.