GuideIntermediate12 min
Export STL for physical-model workflows
Set STL scale and placement, choose cleanup and topology policy, then verify dimensions and printability in the intended slicer.
- Applies to
- Current Prism release · Navisworks Manage 2025–2027
- Availability
- Core and higher
- For
- Fabrication and physical-model teams
- Last reviewed
Recommended starting values
| Setting | Default | Why |
|---|---|---|
| Encoding | Binary | Smaller and broadly supported by slicers. |
| Scale | 1:100 | Turns building dimensions into a practical physical-model scale. |
| Coordinate convention | Millimetres | Common slicer assumption; STL itself remains unitless. |
| Origin | Center on build plate | Centers X/Y and moves minimum Z to zero. |
| Precision | 3 decimals | Defines final coordinates and the weld grid. |
| Triangle ratio | 100% | Keeps all input triangles until reduction is intentionally tested. |
| Validation | Report | Publishes valid STL while exposing topology findings. |
Scale and place the model
A 10 metre object exported at 1:100 is written as 100 numeric units and should be imported as 100 mm. Ratio mode supports common architectural scales. Fit build volume uses the smallest uniform scale that fits the configured X/Y/Z dimensions and margin; it never distorts axes independently.
- Use Center on build plate for slicers and float precision.
- Use Preserve world only for a reference workflow that needs the scaled federation origin.
- Per-source outputs share one federation center and one resolved scale so they can be reassembled.
Cleanup and topology
- Cleanup can weld rounded coordinates, remove non-finite/zero-area and same-winding duplicate triangles, and rebuild facet normals.
- Triangle reduction runs after section clipping. Keep 100% until the baseline output is accepted.
- Report mode records boundary, non-manifold, inconsistent and other topology findings but can still publish the STL.
- Require Closed Manifold blocks an empty result, boundary edges, non-manifold edges, inconsistent shared-edge orientation or opposed coincident faces.
- Cancellation or a blocking topology result leaves an existing destination untouched.
Verify in the slicer
Import as millimetres
Confirm the slicer does not apply another automatic scale.
Measure known dimensions
Check X, Y, Z extents and one known element length.
Read topology warnings
Compare the slicer's repair findings with the Prism audit.
Inspect thin and unsupported features
Apply printer/material rules outside Prism.
Slice a representative section
Review layers, supports, connected shells and bed placement before the final full model.
Related guidance
Choose an export format and compatible settingsCompare Prism output formats, plan availability, packaging, coordinate conventions and the most important interoperability limits.Choose exactly what Prism exportsUse whole-model, selection, saved/search-set, visibility, source-model and section controls without losing required context.Validate an export and read the reportsConfigure Prism checks, IDS validation, halt-on-blocking policy, HTML/JSON/CSV reports and BCF issue output, then decide whether a result is deliverable.