To get an accurate 3D printing quote you need a 3D model file — STL or STEP — exported in millimetres, watertight (manifold), with all bodies unioned. STEP is preferred for tolerance-critical parts because it stores exact geometry; STL is fine when exported at high resolution. Here is exactly what to export and how to check it before you submit.
Key Takeaways
- STEP = best for precision and editability; STL = universal mesh, export at high resolution.
- Always set units to millimetres — STL has no embedded units.
- The mesh must be manifold (no holes, no inverted normals).
- Boolean-union overlapping bodies into one solid before export.
- 2D PDFs and images can''t be quoted directly — but we can build CAD from a sketch.
STL vs STEP: which should I send?
STEP (.step/.stp) is a CAD-native format that preserves precise surfaces — ideal when tolerances matter or we may need to tweak geometry for printability. STL (.stl) is a triangulated mesh understood by every slicer; export it at the finest resolution (chord height ≤0.001 mm in SolidWorks). When in doubt, send STEP; send STL only if that is all your tool exports.
What else can I submit?
| Format | Quotable? | Notes |
|---|---|---|
| STEP / STP | Best | Exact geometry, editable |
| STL | Yes | High-res export only |
| OBJ / 3MF | Yes | Good for colour/multi-material |
| IGES / X_T | Yes | CAD interchange |
| PDF / image | No (directly) | We can model it for you |
How do I check my file is ready?
Open it in a free tool like Meshmixer or Microsoft 3D Builder and run the auto-repair / "is it watertight?" check. Confirm dimensions read in millimetres. Our CAD file preparation checklist and file formats guide cover the full pre-flight.
Frequently Asked Questions
What if I only have a 2D drawing?
Send it — our industrial-design team can build a print-ready 3D model from a drawing or sketch.
Is my file kept confidential?
Yes, under a mutual NDA with encrypted, purge-on-request storage. Upload securely here.