← CAD and mesh conversion guides

OCCT conversion workflows

STEP to STL

Convert STEP or STP to STL through OCCT. Tessellate BRep surfaces or transfer existing mesh data, with control over deflection and output scale.

Build this conversion into your application with OCCT readers, writers and the commercial components identified below.

Ask about this workflow
Input interface
OCCT STEP reader
Processing route
CAD to mesh
Output interface
OCCT STL writer

Convert STEP geometry to a triangle mesh

A STEP-to-STL workflow prepares CAD data for slicers, mesh processing and geometry-only delivery. STEP and STP are two extensions used for native STEP files. The input may contain BRep geometry, mesh data, or a combination; the conversion must inspect the representation before deciding whether tessellation is needed.

For BRep faces, generate a surface mesh with the required chordal and angular deflection. For mesh input, use the existing tessellation and perform any preparation required by the destination. Export the resulting triangles with the OCCT STL writer.

Prepare the model for its destination

  1. Read the STEP file and identify the parts to export.
  2. Apply the required assembly placements and agree on the output coordinate scale.
  3. Tessellate BRep surfaces, or prepare the source mesh.
  4. Write STL and reopen it in the intended receiving application.

Express Mesh provides element-size and deflection controls. BRepGraph Advance offers another meshing workflow with configurations for visualization and material removal.

What changes in STL output?

STL carries triangle geometry. Product names, assembly hierarchy, PMI and materials need another delivery format or an accompanying application record. Units must be agreed with the receiver rather than inferred from the STL filename.

For printing, check open boundaries, orientation, scale and the selected parts. Tessellation alone does not repair all invalid geometry or make an assembly suitable for printing. Retain the original STEP model when later CAD editing or a different tessellation may be required.

Conversion integration

Build a STEP to STL workflow

Share the source and receiving applications, representative files, required attributes and throughput. We can scope SDK evaluation or an integrated conversion service.