Power Fillet Overview:
Power Filleting provides Rhino with filleting
tools typically only found in powerful high-end modeling software.
Power Filleting for Rhino enables the following advanced filleting
functionality:
Power Fillet Usage:

Select Assign Edges to start Picking Edges
Note that the selection of an edge automatically selects other tangent edges.
In this case the
selection of the line also puts fillet circles on the tangent arc and other
line.

This is the Result of the three tangent edge fillets. Note that the fillet
rolls over the hole. This
is one of the large radius cases handled by Power Filleting.

The user can select different radii for individual edges or groups of edges as
shown here.

Here is the result of filleting with different radii. Note the fillet
rolling over the rectangular hole and
the fillet radius being larger than the lower right hand surface. Note
that a blend surface is created
in this case.

There are two ways to specify a Variable Radius Fillet. The first is by
selection along an edge
to be filleted. Use the "Along Edge" button to use this interactive
technique. Note to enable
the "Along Edge" button you need to select the "Variable Radius" Fillet Type.2

Along the Edge first asks for you to select an edge. Once done it asks you
to select points
along the edge using the mouse. The first point needs to be at one end of
the edge, the second
needs to be the end of the edge. The second point (end of the edge) is
selected automatically
after the first point is selected (using the opposite end of the edge). After you define the start
and end you
can specify interior radii. To complete the definition you can hit the "Return" key.

As you are selecting points along the edge you can change the radius for the
next point to
be selected by typing a radius into the PowerFillet dialog box, or into the Rhino command
line and then hitting
return. Here we have changed the radius from 1 to 2 for the end point.

The final "Along Edge" selection might look something like this. If
you have problem remember
to be careful to specify the two end points first.

This is the dialog display after "Along Edge" selection. Note that the
percentages and Radii
are displayed in the list box. You may edit either the percentages (must
be between 0 and 100)
or the corresponding radii and reselect the edge to effect the change.
Note that it is possible to
remove individual edge fillets using the "Un-assign Edges" and to remove all
edges using the
"Un-assign All" button. The "Assign All Edges" button assigns the current
filleting parameters
to all edges in the object.

Here is the result of the variable radius fillet.

You may also type in percent/radii pairs in the "%,Radius Pair(s):" edit box.
You can type in
several as shown here or one pair at a type separated by comas. When you
select "Add Pair(s):"
the pairs will be sorted and added to the list box. Note that you can edit
the values by clicking
on the pair you wish to edit. You can also delete a pair or delete all
pairs. Note that the values
shown in this box only applies to edges yet to be filleted. If you want to
change a variable radius
fillet of an edge you must reselect the edge.

This shows the result of the variable radius applied along the 3 tangent edges.
Note that the
order of the Fillet Radii depends on the selected edge. If we selected the
top edge instead of
the side edge the shape of the fillet would be reversed.

There are different cross section types that may be used. Normally
filleting is done with
either a circular or linear cross section. We also provide a non-rational
approximated
arc and a blend curves (G1, G2, G3). The "Buldge" of the Blend Curve can be adjusted
to
produce various effects. The G2 Blend Curve uses the second derivative of
the adjacent
faces to produce a smooth, continuous curve. The G3 Blend Curve uses the
third derivative
of the adjacent faces to make the rate of curvature change continuous across the
boundaries.
The following illustration shows the same filleted elbow with each of the Blend
Curve options.

The elbows are shown in both a shaded representation
and with the Rhino zebra display.
The elbows on the left use G1 Blended Curves, while the ones in the middle use
G2 Blended
Curves, and the ones on the right are G3 Blended Curves.

This object has the Circular Arc Fillets. Note how the fillet surfaces
tend to stand out because
of their constant curvature.

This object has the G1 Blend Curve fillets with the same offset radius (0.8) which
produces the same
rail curves. Note the reflective properties of these fillets gives the
object a more natural look as
opposed the manufactured look of the Circular Arc fillets.

Here we have used a linear cross section to produce this chamfered object.
Note that linear
cross section is often used with the Constant Distance fillet type.

This object shows the G1 Blend Curve cross sections with a weight of 2.0. It
gives a very nice
kind of a worn edge appearance.

Here is what a G1 Blend Curve cross section looks like with a weight of 0.4.