Why send a STEP file instead of an STL?
A STEP file (ISO 10303) stores your part as precise solid geometry. An STL stores it as a mesh of triangles with no units. Starting from STEP means:
- No unit mix-ups. STEP carries millimetres or inches with the file, so a 25 mm part doesn’t arrive at 25 inches — or 0.98 mm.
- True curves. Holes and fillets stay round. We mesh the model at the resolution the printer needs instead of inheriting a coarse export.
- Better review. We can measure walls, holes, and clearances on the real geometry before quoting.
Read the full comparison in STEP vs STL for 3D printing.
What to include with your file
- Quantity — one prototype or 200 production parts change the best approach.
- Intended use — loads, temperatures, outdoor exposure, chemicals, mating parts.
- Critical dimensions and tolerances — tell us which features have to fit something.
- Finish and colour preferences, if any.
- Destination and target date.
Before you upload
Export a single solid body (or a single part file) in millimetres if you can. If your design is an assembly, send the part you need printed, or email us to discuss multi-part jobs. Not sure how to export? Follow our step-by-step export guide for Fusion, SolidWorks, Onshape, Inventor, FreeCAD, and Rhino.
Questions
Can you 3D print directly from a STEP file?+
Yes. STEP (.stp or .step) is the file format we ask for. We convert it for printing ourselves, at the resolution the part needs.
What is the maximum STEP file size?+
25 MB per request. Most single parts are well under that. If yours is larger, email sales@nanoarc3d.com.
I only have an STL. Can I still order?+
Yes. Upload STL, OBJ, or 3MF files on the same form. Tell us the intended size in millimetres, since mesh files carry no units. More on STL printing.
Is my CAD file kept private?+
Uploaded models are stored privately and are only available to our team and the production partners needed to quote or fulfil your order. We do not sell or publish your models.
Last updated October 27, 2026 · NanoArc3D