Mesh TrimByPlane

    From FreeCAD Documentation
    Other languages:

    Mesh TrimByPlane.svg Mesh TrimByPlane

    Menu location
    Meshes → Cutting → Trim mesh with a plane
    Default shortcut
    Introduced in version
    See also
    Mesh PolyCut, Mesh PolyTrim


    The Mesh TrimByPlane command trims faces and parts of faces on one side of a plane from a mesh object.


    1. Select a single mesh object and a single Part plane. The (extended) plane should intersect the mesh object.
    2. There are several ways to invoke the command:
      • Press the Mesh TrimByPlane.svg Mesh TrimByPlane button.
      • Select the Meshes → Cutting → Mesh TrimByPlane.svg Trim mesh with a plane option from the menu.
    3. The Trim by plane dialog box opens.
    4. Select the side you want to keep by pressing one of the buttons:
      • Below
      • Above
      • Split: removes the faces and parts of faces above the plane, and creates a new mesh object containing them.


    See also: FreeCAD Scripting Basics.

    To trim a mesh with a plane use its trimByPlane method.

    import FreeCAD as App
    import Mesh
    # Create a non-parametric box-shaped mesh:
    msh = App.ActiveDocument.addObject("Mesh::Feature", "Mesh")
    msh.Mesh = Mesh.createBox(30, 40, 50)
    msh.ViewObject.DisplayMode = "Flat Lines"
    # Define a plane by a base point and a normal vector:
    pnt = App.Vector(25, 0, 0)
    nor = App.Vector(0, 0, 1)
    # We need to work on a copy of the msh.Mesh object:
    new_msh = msh.Mesh.copy()
    # Trim that copy:
    new_msh.trimByPlane(pnt, nor)
    # Update msh.Mesh:
    msh.Mesh = new_msh