Model prep
Repair and optimize a model
Patches holes, flips inverted normals, drops stray shells and, if you ask, lightens the mesh. The file is sent only for the computation and is never stored.
- Input: Model
- Output: Repaired model
Building a mold and looking it over needs no account. Signing in is only required to download.
What you get
- A closed model: holes patched, inverted normals flipped, degenerate triangles dropped. The slicer stops asking for a repair.
- A report of what exactly was fixed — in numbers, not a “done”. You can see whether the model was really broken at all.
- Optionally a lighter mesh: down to a quarter of the original, with the shape preserved.
How it works
- 1Load the model that was refusedSTL, OBJ or 3MF. Before you press anything the tool already reports what it found: open edges, zero-thickness walls, mesh weight. Self-intersections and duplicate faces are searched by a separate button — a few seconds.
- 2Choose how deep the repair goesBy default only the cheap steps run: they do not touch the geometry, they only stitch what came apart. If that is not enough, turn on aggressive repair — it rebuilds the whole body from voxels.
- 3Download it and carry onYou get one STL or 3MF at the same size and in the same position. Both the slicer and our mold generators accept it.
If something went wrong
Symptom, and what to change
- Still “not watertight” after the repair
- A complex self-intersection: turn on aggressive repair.
- Small details disappeared
- The voxel was too coarse: set the size by hand — 0.1 mm — or turn aggressive repair off.
- The model fell apart into pieces
- There were several from the start: turn on “Largest part only”.
- Fewer triangles than in the original file
- The mesh is simplified in the browser before it is sent — only a few megabytes go into the computation. Both numbers are shown under the model, and the original density cannot be restored.
Questions
Good to know
Why would I need this if the model prints fine?
If it prints, you do not. People come here when the slicer says “repair required”, or when our mold generator refused the model: it needs a closed body, otherwise there is no telling which side is inside and which is out.
What exactly gets fixed?
Vertices that drifted apart are merged, zero-area triangles are dropped, inverted normals are flipped by walking the neighbours, and holes up to a hundred edges are closed with a patch. If that is not enough, the body is rebuilt from voxels entirely — then everything is fixed, including self-intersections and fused walls.
Will the repair restore a missing part of the model?
No. A hole is closed with a patch along its rim, not with a guess about what used to be there. If the figurine has no arm, no arm will appear — a flat surface will appear where the cut is.
Why did the small details disappear?
That is aggressive repair: it rebuilds the body on a voxel grid, and anything finer than one voxel does not make it in. Use a smaller voxel or clear the checkbox — then only the cheap steps run, and they leave the geometry alone.
Why does the file have fewer triangles than what I brought?
The model is simplified in the browser before it is sent: only a few megabytes go into the computation, and a heavy scan does not fit in them. Both numbers are shown under the model. Density above what went into the computation cannot be brought back.
Will the sizes change?
No. The bounding box, the position and the units stay the same — we do not scale or rotate the model. If it arrived in metres, it stays in metres: that is fixed in the slicer.
Does my model go to your server?
It does — but only for the duration of the computation. We do not store it: no archives, no copies. Until you press “Repair”, the file never leaves your browser.
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