3D Scanning to Production CAD

A scan is not a model

This is the most common misunderstanding about 3D scanning. A scan produces a mesh — millions of triangles describing a surface. It captures shape, but it has no features, no dimensions and no design intent. You cannot change a diameter on a mesh, because the mesh does not know it has one.

Cleaning the scan

Raw scan data arrives with noise, gaps where the scanner could not see, and stray geometry from the fixturing. Before any modelling begins the mesh is cleaned up, holes are filled and the part is aligned to a sensible coordinate system — usually its functional datums rather than wherever it happened to sit on the scanner.

Rebuilding with features

The real work is interpretation: recognising that a scanned region is a cylindrical boss, reading its true axis and diameter from the data, and rebuilding it as a modelled feature. Done properly, the result is a parametric solid whose dimensions are round numbers where the original design intended round numbers — not 49.97 mm because that is what a worn part measured.

Verifying against the scan

The finished model is compared back against the original scan as a deviation check. That comparison is what separates a model that is genuinely accurate from one that merely looks convincing, and it is the point at which the work can be signed off with confidence.

What was delivered

Cleaned scan data, a fully parametric CAD model rebuilt with proper features, a deviation report against the original scan, and manufacturing drawings.