Openly licensed CAD files for end-to-end tests
Question: where can TeamCraft get real native files of the common CAD programs – parts and assemblies – that may be redistributed in a public MPL-2.0 repository, to test the import, the format detection, the preview images, the reference scan and the STEP preview end to end? Investigated on 2026-11-04.
Sources checked
| Source | What it offers | Licence | Usable |
|---|---|---|---|
| NIST MBE PMI validation and conformance testing | test parts CTC 01–05, FTC 06–11, STC, HTC in native CATIA V5, Siemens NX, Autodesk Inventor, PTC Creo and SolidWorks plus STEP AP203/AP242 and PDF; the MTC box assembly in NX (with JT) and SolidWorks (with ACIS .SAT) | “The test cases, CAD models, and STEP files can be used without any restrictions.” NIST asks for an acknowledgement and does not allow its logo in promotional material | yes |
| GrabCAD and similar community libraries | many native files | no licence per file, terms of the site only | no |
inventor-kit (PyPI) | reads .ipt/.iam, files not distributed | PolyForm Noncommercial since 0.3.0 | no |
| SolidWorks repositories of open hardware projects | .SLDPRT/.SLDASM | mostly no licence, CC BY-SA or unverified “MIT” claims | no (not verifiable / share-alike) |
| Solid Edge community samples | automation code samples | no model files with a stated licence found | no |
Solid Edge is the gap: no openly licensed native Solid Edge files were found. Options: create small test parts and an assembly with Solid Edge (Community Edition) and publish them under CC0, or ask the Solid Edge community for donated files.
Decision
A curated subset of the NIST files goes into tests/fixtures/cad/nist/
(about 30 MB), with the NIST terms, the acknowledgement, the source of every
file and its SHA-256 in tests/fixtures/cad/README.md:
- CTC 01 in every native format: Inventor 2021
.ipt, NX 1980.prt, SolidWorks 2018.SLDPRT, Creo 10.prt.5(a Creo iteration), CATIA V5.CATPart, and STEP AP203 and AP242; - FTC 11 as small files for fast tests: Inventor
.ipt, SolidWorks.SLDPRTand a 7.6 kB STEP AP203; - the MTC box assembly in SolidWorks (
.SLDASM, parts,.SAT) and in NX (assembly and part.prt,.jt) – real assemblies for the reference scan and the folder import.
A test (tests/cad_fixtures.rs) checks every file against its SHA-256 and
the expected TeamCraft format, and records what the heuristics really find
in these files: preview images (Inventor, SolidWorks), referenced part files (SolidWorks and NX assemblies) and the STEP
3D preview.
Sources
- NIST – Download free CAD models and STEP files (terms quoted from the Disclaimers section of that page), project page, data catalog entry, MTC: Design, Manufacturing, and Inspection Data for a Box Assembly
- inventor-kit on PyPI
- SolidEdgeCommunity/Samples
Results with the files (2026-11-04)
What TeamCraft found in the NIST files (tests/cad_fixtures.rs):
- Format detection: all 32 files are recognised correctly – NX parts by
their
SPLMSSTRheader, the Creo iteration.prt.5, CATIA V5, JT and ACIS included. - Preview images: Inventor 2021 parts carry a PNG of about 26 kB, which is found. SolidWorks 2018 files carry none that can be found: since 2015 SolidWorks keeps its streams in compressed segments of its own container.
- Reference scan: the NX assembly names all eight part files. The
SolidWorks 2018 assembly names none (compressed, see above). False
references: NX parts report earlier file names of their save history and
binary noise, the STEP header its export name (
FILE_NAME), JT files noise. - 3D preview: the small STEP files are tessellated.
The gaps are ignored tests in tests/cad_fixtures.rs and fixes in
docs/OPEN_WORK.md.