Repair Invalid CAD Parts

Use the Repair parts tool to heal invalid CAD parts after import.

The tool attempts to fix the following:
  • invalid topology
  • invalid edge and vertex tolerances
  • invalid geometry
  • self-intersecting geometry
  • non-G1 geometry
    Note: A surface can be composed of several NURBS surfaces known as patches. These patches should be fitted together in a way that the boundaries are invisible. This is mathematically expressed by the concept of geometric continuity. One of the options to establish geometric continuity is by means of Tangential continuity (G1). It requires the end vectors of two curves or surfaces to be parallel which eliminates sharp edges.
  • missing edge or vertex geometry
  • missing vertices
  • vertices not on the curve of an edge
  • edges and vertices not on the surface of face
  1. After you import a CAD model, a message appears when invalid parts are found.
    • To repair the geometry errors now, click Repair.
    • Otherwise, click Cancel. To repair them later, from the Construction History browser, right-click the CAD Import construction feature, and then select Run Repair.
  2. When you choose to repair, the Repair parts dialog box appears.
    The table lists Invalid parts, all of which are automatically selected for Repair.

  3. In general, you can leave all parts selected, accept the default settings, and then click the Repair button.
    The status of healed parts changes to Valid.
  4. If one or more parts are still Invalid, you can select each individually, configure the settings, and then click the Repair button.
    Tip: To isolate an invalid part for closer inspection, select the part name in the table of the dialog box, and then press the I key.
  5. To accept the changes, click OK.

Repair Parts Settings

For most cases, the default settings will suffice. When modifying the settings, a general rule of thumb is to use the smallest tolerance possible, or no tolerance at all, if the option allows.
Note: Specified tolerances are given in the model unit.
Repair deviation
The deviation between original and repaired geometry (the tolerance for repairing the part).
Use edge deviation
Turn on this option to enter the edge deviation.
Edge deviation
Turn on Use edge deviation, and then enter the deviation between original and repaired edges (the tolerance for repairing edges).
Angular tolerance for geometry smoothening (degrees)
The tangent angle change in degrees above which G1 discontinuities are removed by splitting topology rather than smoothening the geometry.
Remove small edges
Turn on this option to enter the Maximum length of small edges.
Maximum length of small edges
Turn on Remove small edges, and then enter the maximum arc length of edges to be removed.
Removal of self-intersections
Choose from the following options.
  • Off: Turn off this setting.
  • Regular: When a surface contains self-intersections located outside its face boundaries, then this portion of the surface will be removed by splitting the surface. This may result in the face being split into multiple faces.
  • Advanced: A more in-depth algorithm is used to fix self-intersecting surfaces.
Suppress surface modifications
Surface geometry is preserved and repairs are confined to repairing face boundaries as far as possible.
Repair face-face errors
Attempt to repair face-face collisions in the body.
Repairing surfaces by simplifying to blends
Choose from the following options.
  • Off: Turn off this setting.
  • Each surface individually: Each surface is cleaned individually by simplifying to blends.
  • Max surface chains: The maximum number of connected surfaces are cleaned by simplifying to blends.
Simplify geometry during repairing
Cleans and removes redundant topologies and geometries from the model during translation. Redundant vertices are deleted, and the associated edges are merged. Redundant edges are removed, and the associated faces merged.