Creating Face-Face Fillets 

The Face-Face Fillet command is used when there is no intersection between the faces or when there are more than two sharp edges between the faces.

This task shows how to create a basic face-face fillet then a face-face fillet using a hold curve.

1. Click Face-Face Fillet in Dress-Up Features toolbar (Fillets sub-toolbar).
   The Face-Face Fillet Definition dialog box appears.

2. Select the faces to be filleted.

3. Enter a radius value in the Radius field if you are not satisfied with the default one.

4. Click Preview to see the fillet to be created.

5. Click More>> to access the Limiting element option.

Limiting Element

6. Click the Limiting element box and select the trimming elements
   An arrow appears on the selected elements to indicate the portion of material that will be kept.

7. Click this arrow to reverse direction to keep the material of the opposite portion.

Contextual commands creating the limiting elements you need are now available from the Limiting element box:

• Create Plane: For more information, see Creating Planes

• XY Plane: The XY plane of the current coordinate system origin (0,0,0) becomes the limiting element.

• YZ Plane: The YZ plane of the current coordinate system origin (0,0,0) becomes the limiting element.

• ZX Plane: The ZX plane of the current coordinate system origin (0,0,0) becomes the limiting element.

• Create Join: Joins surfaces or curves. See Joining Surfaces or Curves.

• Create Extrapol: Extrapolates surface boundaries or curves. For mor information, see Extrapolating Surfaces and Extrapolating Curves.

If you create any of these elements, the application displays the corresponding icon next to the Limiting element box. Clicking this icon enables you to edit the element.

8. Click OK.
   The faces are filleted. The fillet is trimmed by Plane.1. This creation is indicated in the specification tree.

Select the Conic parameter check box to vary the section of the fillet.
For a parameter between or equal to:

• 0.5, the resulting curve is a parabola.

• 0 < parameter < 0.5, the resulting curve is an arc of an ellipse.

• 0.5 < parameter < 1, the resulting curve is a hyperbola.

• If the Conic parameter option is selected, the Edge(s) to keep, Hold curve and Spine fields cannot be selected.

• Conical fillets do not handle twist configurations. If a twist is detected, the fillet operation fails.

• If the fillet surface curvature is lower than the support curvature, fillet surface relimitation may fail. In this case decrease the Conic parameter.

• The Edge(s) to keep and Hold Curve options are grayed out, when the CFO license is not available.

Interrupting Fillet Computations

In case you made a mistake when defining a fillet (wrong radius value for example), you can interrupt the feature computation launched after clicking OK, provided that the computation requires at least 5 seconds to perform.
When a computation exceeds 5 seconds, a progress bar appears and provides a Cancel option. To interrupt the operation, just click that Cancel button. This interrupts the process and then displays an Update Diagnosis dialog box enabling you to edit, deactivate, isolate or even delete the feature.

This capability is available for any types of fillet features you are creating or editing.

Hold Curve

Instead of entering a radius value, you can use a hold curve to compute the fillet. Depending on the curve's shape, the fillet's radius value is then more or less variable.

Open the FaceFillet2.CATPart document.

Set Body.1 as the current object (to do so, use the Define In Work Object command).

The Generative Shape Design product license is required to access this capability. 

• Contextual commands creating the curves you need are available from the Hold Curve field:

  • Create Line: For more information, see Creating Lines.

  • Create Join: Joins surfaces or curves. For more information, see Joining Surfaces or Curves.

  • Create Boundary: For more information, see Creating Boundary Curves.

  • Create Extract: For more information, see Extracting Geometry.

  • Create Intersection: For more information, see Creating Intersections.

  • Create Projection: For more information, see Creating Projections.

  If you create any of these elements, the application then displays the corresponding icon in front of the Hold Curve field. Clicking this icon enables you to edit the element.

1. Click Face-Face Fillet . Select both faces as shown then expand the dialog box to access further options.

2. Select Join.2 as the hold curve. The curve must be sketched on one of the selected faces.

Spine

3. Select Sketch.1 as the spine. The spine provides a better control of the fillet.
   The spine can be a wireframe element or a sketcher element.
   To compute the fillet, the application uses circles contained in planes normal to the spine. It is then possible to control the shape of the fillet.

Contextual commands creating the spines you need are available from the Spine field:

• Create Line: For more information, see Creating Lines

• Create Join: Joins surfaces or curves. For more information, see Joining Surfaces or Curves.

• Create Boundary: For more information, see Creating Boundary Curves.

• Create Extract: For more information, see Extracting Geometry.

• X Axis: The X axis of the current coordinate system origin (0,0,0) becomes the direction.

• Y Axis: The Y axis of the current coordinate system origin (0,0,0) becomes the direction.

• Z Axis: The Z axis of the current coordinate system origin (0,0,0) becomes the direction.

If you create any of these elements, the application then displays the corresponding icon in front of the Spine field. Clicking this icon enables you to edit the element.

4. Preview the fillet.

5. Repeat the operation and select Copy of Sketch.3 as the spine.
   The fillet has a different shape.

Maximum length of the fillet surface is limited by the extents of the input spine curve.

More About Near Point Option

The Near Point option allows you to select faces as per your requirement to form face-face fillet. If the selected faces to fillet form multiple ribbons, you can specify a reference point nearest to the required ribbon in the Near Point box.

In the below example, two ribbons are formed from the selected faces:

In this case, you can specify a reference point in the Near Point box. The ribbon nearest to this reference point is selected. The result is as shown below:

The following contextual commands for creating the reference point are available from the Near Point box:

More About Edge(s) to keep Option

You can specify the one or more edges of the support body to be kept and create the fillet surfaces with Hold Curve and Edge(s) to keep options as support. Consider the following two cases:
 

• Initializing the fillet ribbon when no portion of ribbon track lies within the limits of the provided support face.
  

• Computing the fillet surface with edges selected as supports for the Edge(s) to keep option where the default fillet ribbon track crosses the edges to be kept.
  

The Edge(s) to keep field is available in the Face-Face Fillet Definition dialog box which is not selectable by default.  On selecting the Hold Curve option,  the Edge(s) to keep field becomes active and selectable.  When an edge to be kept is selected, it turns purple in the geometry.

This option is available only if a Cast & Forged Part Optimizer license is used.

• You can perform thickness, shell and boolean operations on the resulting fillet surface.

• You can specify the limiting element.

• The edges selected for the Edge(s) to keep option should not be of round corner type.

• The edges selected for the Edge(s) to keep option should be explicitly specified and sharp. They should not be border edges.

• The fillet ribbon has zero radius at the points where the Edge(s) to keep intersects the Hold Curve. There can be maximum two such points in a fillet ribbon; one at each end of the fillet ribbon.

• The fillet operation may fail in cases where Edge(s) to keep intersects the support face of Hold Curve.

• The fillet operation fails if twists are encountered.