Reshaping Corners  

Sometimes, while filleting you can see that corners resulting from the operation are not satisfactory. The "Blend Corners" capability lets you quickly reshape these corners. 
Open the BlendCorner.CATPart document.

  1. Click Edge Fillet and fillet the four edges as shown using 5mm as the radius value.
    Careful! When you select edges, the order of selection affects the final shape of the fillet. This explains why you may sometimes encounter error messages when filleting.
    To obtain the shape we need for our scenario,  select the edges counter-clockwise.

    Take a closer look at the resulting corner: the shape style is not satisfactory. 

  2. To round the corner again, double-click the fillet and in the dialog box click the More button to access additional options.

  3. Right-click the Blend corner(s) field and select Create by edges. In our example, only one corner is detected. The application shows it in the geometry area (3D text).

  4. The setback distance determines for each edge a free area measured from the vertex along the edge. In this area, the system adds material so as to improve the corner shape. The tangent edges are automatically selected if they are in propagation with the selected edges. This allows you to specify the setback distance value exceeding the length of the corresponding concurrent edges.

The Blend Corner option is available through the Variable Radius Fillet command too.

  1. Enter a value in the setback distance field. For example, 13.

  2. Click Preview to examine the result.
    To edit the distance for the top edge, click 13 and enter 22 as the new value in the Setback distance field.

  3. Repeat the operation for the edge below (see arrow) using the same distance value, 22.

  4. Click OK to confirm the operation.
    The corner is reshaped.
 

More About Blend Corners

When editing an edge fillet containing at least one blend corner, the following options are available in the Blend corner(s) contextual menu.

  • Reframe On: This command reframes the model at the selected corner.
  • Create by edges:  The selected and propagated edges are taken into account. You do not need to select the concurrent edges of the corners. This command does not remove the existing blend corners.
  • Create by vertex: This command is available even if some corners are already defined. It automatically adds the corresponding blend corner with default setback distance. The concurrent edges of the selected vertex are added to the list of object(s) to fillet (case Minimal/Tangency) if these edges are new ones or if they are not part of the propagations.
  • Edit: This command displays a list of editable setback values. However, an error message is displayed if you edit multiple blend corners.
  • Remove: This command removes the selected blend corners.

When no corner is created, only the Create by edges and Create by vertex commands are displayed in the contextual menu.