Toolbar Menu

Extract Mesh

Not on menus.

The ExtractMeshEdges command separates edges from the parent mesh determined by an angle between mesh face normals.

The command may help if you have a mesh that came from a polysurface but no longer have the polysurface. Using the command with the Unwelded option creates polyline approximations of where the edges of the polysurface were.


Command-line options

Extract edges by


Extracts edges with coincident vertices.

Break angle

The angle between the face normals of adjacent faces.

Greater than

Specify a minimum break angle.

Select Edge

Specify an example edge to set the minimum break angle.

Less than

Specify a maximum break angle

Select Edge

Specify an example edge to set the maximum break angle.

Join results

Joins the resulting curves.


Toolbar Menu

Not on toolbars.

Not on menus.

The ExtractNonManifoldMeshEdges command extracts the mesh faces that have non-manifold edges from a mesh object.

Non-manifold edges

Edges of polysurfaces or meshes that have more than two faces joined to a single edge are non-manifold.

The illustration shows a mesh and a polysurface with non-manifold edges highlighted with the ShowEdges command.


  1. Start the command.
  2. Set command-line options.
  3. Select a mesh.

Command-line options


Only extracts the faces with non-manifold and naked edges.



See also

Collapse mesh faces and vertices




Rhinoceros 6 © 2010-2020 Robert McNeel & Associates. 11-Nov-2020