Loop Fillet Feature
Insert 
Fillet/Chamfer (Part Level)
Use this command to create a constant
radius fillet along the edge loop of a face. There are advantages to using
this command over filleting each edge individually. You can select all
of the edges by selecting the face.
This command also creates a more stable part. If the face is later modified, the fillets will adapt accordingly during the next regeneration. See also Partial Results Filleting (CAD Tips & Techniques).
Faces - Select the faces to fillet.
Radius - Specify the fillet radius.
Loop - Specify which face loops to fillet. Select Inner, Outer, All or Selected.
Edges - If you picked Selected for the Loop option above, select the edges to fillet.
Relief
- Use this option to control the amount of smoothing at a corner patch.
With the Relief set to zero (its default value), the filleting
algorithm decides where to trim the rails of the fillets meeting at a
corner. Values greater than zero add additional relief to corners.
Specify the set back distance.
The Relief value is a default value.
Once set it remains in effect until it is reset back to zero. The Relief
value is a distance measured in the default part units. If a negative
value is entered, the value is reset to zero. Note that any value larger
than the smallest fillet encountered will cause the fillet operation to
fail. The Relief distance is fixed for all corners created in a
single fillet operation.
Arc
type - Use this option to specify the fillet arc type to create.
Select from the following.
Circular Arc - Create fillets using circular arcs.
Conic Arc - Create fillets using conic arcs.
Conic ratio - If Conic Arc is selected for the Arc Type above, enter the conic ratio within the range of 0 - 1. (default = 0.5)
Hold fillet to edge - Check this box to specify if the fillets should be held to near by edges.
