Review supported triangle cleanup and save a separate 3MF copy to verify.
Choose a 3MF file
Processing stays in this browser. Review the removal plan before saving a separate copy. This tool removes supported triangle records; it does not fill holes, weld vertices or correct winding. The original remains unchanged.
Select a non-empty .3mf file, up to 25 MiB.
The repair plan is not ready yet.
A duplicate-face example
Download the duplicate-face cube package. It declares millimetres, one mesh and one build item. The retained local repair control observes 13 source triangles and one duplicate. Leave only duplicate removal selected, run the local repair and compare the before/after counts: 13 to 12 triangles, with no intended dimension change. Save the repaired package and open it again in 3MF Preflight and your receiving slicer. This is generated mathematical geometry, not a physical print test.
These observations use the browser repair implementation with duplicate removal alone. Retained repair evidence records fixture/output hashes, settings, source revision and reopened unit/build checks. This is not a production processor or receiving-slicer observation.
This browser tool removes selected duplicate, degenerate or invalid-index triangle elements from the relationship-selected model XML. It keeps vertex coordinates, other XML elements and the decompressed payloads of other ZIP parts. It creates a new compressed package; the ZIP bytes and compression layout are not identical to the original. Retaining a vendor setting as a payload does not prove a receiving slicer will use it correctly.
Schematic: triangle elements change in a separate package; unit and build context are retained rather than flattened into STL.
Source mesh counts and placed geometry answer different questions
The removable-triangle plan examines mesh definitions in the model XML; the preview resolves supported build items, component references and transforms. A shared resource can have several placements without several independent repair operations. Compare the declared unit, resolved build count and dimensions before trusting the saved copy.
The removal-plan screen matches triangle vertex-index triples within each mesh, ignoring order, and skips duplicate, degenerate and invalid-index records before counting edges. Its edge keys use source indexes across the model part, so these are limited plan diagnostics, not a per-resource or placed-build topology proof. Invalid indexes that prevent the resolver completing do not reach a repair plan. Recheck the saved build with a separate method.
Unsupported or unresolved packages produce an error rather than a flattened replacement. Open edges, non-manifold connectivity, self-intersections and missing surfaces are not reconstructed. This local plan does not correct winding. An empty plan means no supported removal is selected, not that every possible issue has been checked.
Choose the right repair route and recheck the saved build. Several placed items can reference one edited resource; confirm quantity, transforms and bounds after saving. These links do not transmit the selected file.
Preserve the original project, especially where colours, textures or printer profiles matter. If the receiving slicer loses an assignment, stop and review the original package there; check core geometry and slicer-project information separately.
