STL scan use

I have a very expensive scanner that scans gemstones and creates STL files. Problem is it creates an open mesh, I want it closed. The mesh has like a 90000 faces, so its hard to find out where it is exactly open. When I try to meshbooleandifference to use the scan as intended, there are all kinds of boolean issues due to the number of mesh. Reduce mesh only works down to a certain amount. Same if I use TONURBS. It becomes an open polysurface. There are so many poly surfaces and I cannot loft or cap it. Is there a way to like sub D a shell around this object ?

I know its hard to picture what I am talking about. is there a way to post the STL here so someone could help me out?

I own an Artec Leo and work with Artec Studio.

Does your scan post processing software not have a feature to close mesh holes?

If not maybe try meshmixer…

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That’s huge… OK, the tools in Rhino you can use:

  • You can try the MeshRepair routine.
  • If there are really holes in the mesh, the command FillMeshHoles may work to fill them.
  • If the mesh is full of naked edges, the command MatchMeshEdge with a certain tolerance may help to re-align the edges and join them so that they are closed.
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Lifesaver. Thanks

Thanks Martin. will be using meshmixer in the future for other things too. Appreciate the tip

Is there a similar command as MatchMeshEdge but for polysurfaces?

No (well, not really). If surfaces are not joining, the edges are out of tolerance. It is possible to use JoinEdge between two out of tolerance edge pairs to force the edges together to join. However, this does not change the underlying surface and its original edges and just results in a false sense of security. If you export these to some other program, they will come apart again. Even internally in Rhino some operations may fail with out of tolerance edges.

If you are working in NURBS geometry, you need to make sure that you create your objects to be joined within tolerance of each other. Otherwise, it’s a recipe for disaster.