Mesh TrimByPlane

From FreeCAD Documentation
Jump to navigation Jump to search
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