FreeCAD: How to create meshes from a solid?

1. Click [File]-[New] in menu bar. Create new document and a solid.

   Creates a solid

2. Switch workbench to Mesh Design wrokbench.

3. Click [Meshes]-[Create mesh from shape...] in menu bar and following dailog will be displayed. Select a shape that you want to meshed and set parameters on the dialog.

   Tessellation dialog

   Mesher that can be used are "Standard", "Mefisto" and "Netgen". Meshes to be created and the parameters of each mesher are as follow.

   • Standard

     Parameter	Behavior
     Surface deviation	If this parameter is smaller, meshes becomes finer.
     Angular deviation	If this parameter is smaller, meshes becomes finer.
     Relative surface deviation	Create meshes depending on edge length.
     Apply face colors to mesh	Set shape color to the mesh.
     Define segments by face color	Set segments to meshes depending on shape colors.

     Surface deviation=0.1
     Surface deviation=0.01

   • Mefisto

     Parameter	Behavior
     Maximum Edge length	Maximum edge length. If this parameter is smaller, meshes becomes finer.

     Maximum Edge length=10.0
     Maximum Edge length=5.0
     Maximum Edge length=2.0

   • Netgen

     Parameter	Behavior
     Fineness	Degree of mesh fineness. If you want to customize parameters, select "User defined".
     Mesh size grading	If this parameter is smaller, meshes becomes finer. A value in the range of 0.1-1.
     Element per edge	If this parameter is larger, meshes becomes finer. A value in the range of 0.1-1.
     Element per curvature radius	If this parameter is larger, meshes becomes finer. A value in the range of 0.2-10.
     Optimize surface	Whether optimization of surface shape will be done.
     Second order elements	Whether second order elments will be generated.
     Quad dominant	Whether meshes will be arranged like hexahedral.

     Mesh size grading=0.3
     Element per edge=1.0
     Element per curvature radius=2.0
     Mesh size grading=0.1
     Element per edge=3.0
     Element per curvature radius=5.0
     Mesh size grading=0.3
     Element per edge=5.0
     Element per curvature radius=10.0
     Enable second order elements

     Enable quad dominant

4. Set paramters in the dialog and click OK to create mesh.

5. Select the meshed solid on model tree and type space key to hide it. Then select [View]-[Draw style]-[Wireframe] in menu bar to set 3D view wireframe display mode. Now you can see the generated mesh clearly.

   Wireframe display mode

6. After confirm that the mesh does not have the problem, export it by [Meshes]-[Export mesh...] in menu bar.

   

   Following formats can be used for exporting.

   • Binary STL (*.stl)
   • ASCII STL (*.stl)
   • ASCII STL (*.ast)
   • Binary Mesh (*.bms)
   • Alias Mesh (*.obj)
   • Object File Format (*.off)
   • Inventor V2.1 ascii (*.iv)
   • X3D Extensible 3D (*.x3d)
   • Stanford Polygon (*.ply)
   • VRML V2.0 (*.wrl *.vrml)
   • Compressed VRML V2.0 (*.wrz)
   • Nastran (*.nas *.bdf)
   • Python module file (*.py)

References

• FreeCAD: How to export shapes as STL file?
• FreeCAD: How to create a solid from meshes?