PrusaSlicer found errors and repaired them. Should you trust it?
PrusaSlicer flags an object with a warning icon and, in most cases, repairs the mesh on import without asking. That is usually helpful. Occasionally it papers over something you needed to know about.
What it means
PrusaSlicer inspects meshes on import. When it finds problems it marks the object and, in most cases, patches them silently so slicing can proceed. The icon is telling you the file arrived faulty — not that slicing failed.
When the repair is safe
| A few open edges | Safe. It closes the gap with the obvious surface, which is almost certainly the one you meant. |
|---|---|
| Degenerate triangles | Safe. Zero-area triangles carry no surface, so removing them changes nothing. |
| Large holes | Risky. There is more than one way to close a big gap and the slicer picks one. It may not be yours. |
| Self-intersections | Risky. The repair resolves the contradiction by choosing a side, which can quietly remove or fill a feature. |
Three ways to handle it
- Compare the preview with your model. Free, immediate, and it catches the bad repairs: look for a filled cavity, a rounded-off corner, or a hole that has closed over.
- Fix it at source for anything that has to fit. For a bracket or an enclosure, a repair that moves a surface by half a millimetre matters. Go back to the CAD and export a clean mesh.
- Send it to us. We will repair it deliberately rather than automatically — from £15.
See what it repaired
The slicer does not really tell you what it changed. Run the original file through the checker and you get the count and location of every fault before any repair touched it. That is what tells you whether the automatic fix was trivial or load-bearing.