Creating Tritangent Shape Fillets

This task shows how to create a shape fillet between three surfaces.
The fillet surface is obtained by rolling a sphere between the selected surfaces. It involves the removal of one of the three faces selected.
This command also lets you create bitangent shape fillets.

Open the ShapeFillet4.CATPart document.

  1. Click Shape Fillet .

    The Fillet Definition dialog box appears.
  2. Choose the Tritangent Fillet type.

  3. Select a surface as the first support element.

  4. Select another surface as the second support element.

  5. Select the surface to be removed. The fillet will be tangent to this face.

    To help you decide on the location an arrow is displayed on each selected surface. You can click on the arrows to specify the desired fillet location.
  6. Click Preview to see the filleted surface:

    You can deselect Trim support 1 and Trim support 2. In this case, the support element involved will not be trimmed and assembled to the filleted surface.
    By default, options are checked, thus relimiting both support elements.
    With only one support element trimmed

    With both support elements trimmed

  7. Use the combo to choose the desired type of extremity for the fillet:

    • Smooth: a tangency constraint is imposed at the connection between the fillet surface and the support surfaces, thus smoothing the connection.
    • Straight: no tangency constraint is imposed at the connecting point between the fillet and the initial supports, generating sometimes a sharp angle.
    • Maximum: the fillet surface is limited by the longest selected support's edge.
    • Minimum: the fillet surface is limited by the shortest selected support's edge.
  8. Click OK to create the shape fillet.

    The surface (identified as is added to the specification tree.
    • In case the selected supports are partially tangent, it is advisable to create an edge fillet.

    • Parameters can be edited in the 3D geometry. To have further information, refer to Editing Parameters.