Creating a Trim Partition

This task shows you how to cut a surface boundary or 3D curve into several areas.
Open TrimPartition_InitP1.CATPart from the samples directory.
You can see the result in TrimPartition_EndP1.CATPart.
  1. Click Trim Partition  in the Process Part Separation toolbar.

  2. Select the elements to split.
    • A surface: The boundary of the surface is computed. Each domain of the boundary is added as a geometrical result.
      The bigger loop (usually the outside boundary) is the Cutting Line. Others are typed as Positioning Holes.
    • A stamping direction: The boundary of the shape that is the input of the stamping direction is considered.
      For each part of this boundary that is associated to a tool direction, cutting lines are computed for the external boundary and positioning holes for the other edges.
      Cutting lines and positioning holes are computed for the other parts, the same way.
    • A surface partition: An inner join is computed with all the partition elements, using the associated unfolded view of each Folded Surface geometrical result, if any.
      Then, the computation is the same as for a surface.

  3. Select the splitting elements.
    • 3D curves: They cut the surface boundary directly.
    • Sketches: An internal extrude of the sketch is computed, in the plane direction. Its intersection with the surface boundary is used to cut the boundary.
    • A plane and create a sketch on the selected plane from the contextual toolbar.

    The elements that split the curve are automatically trimmed at the intersection with the boundary, only their longest part is kept.

    • Each domain of the input wireframe is trimmed by the trim elements. The kept side is either the one with the most intersections with trim elements, or the longest side.
    • The resul of the trim is a Scrap Cutter.

    The partition of the boundary is created. Each part of the boundary is kept, ensuring the whole part is cut by all the cutting elements.

  4. Select the Scrap Cutters elements (wireframe).
    Depending on the geometries inside the sketch that defines the scrap cutters, geometries are extracted and computed with a type (Scrap Hole or Scrap Line). This type can be changed from the contextual menu.
    Existing older trim partitions are updated to create scrap cutters types.

  5. Check the result under Partition.
    • Select one element.
      It is highlighted in the work area.
    • Optional: Change its type from the contextual toolbar.

  6. Edit the minimum and maximum tolerances of the curves as required.
    For more information, see Tools > Options.

  7. Choose intermediate geometries to associate to the selected element.
    The table of results is updated.

A Partition Set is created.
such as the blue lines and blue boundaries of green holes.

Result areas are stored under geometrical sets:

  • Planned Elements (Associated to a process action)
  • Not Planned Elements (Not associated to any process action)
  • Ignored Elements (Not used by the process).
as
  • Positioning Hole
  • Painting Hole
  • Cutting Line
  • Intermediate - name.