Surface Fillet Quick Help

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Pwr_SrfFillet creates fillets between multiple surfaces.  It is similar to the Pwr_Fillet command, which works on solid geometry.  It creates the fillet based on user settings of the various parameters (see descriptions below), and based on the user's selection of surfaces

1) Break apart a stock object into elements of an editable mesh or into separate objects using cutters which are either solids or surfaces.
2) Use a single or multiple cutters on one or more stock objects at the same time.
3) Do a volume decomposition of a set of cutter objects.
4) Use a single cutter many times without maintaining the history.

Here is how to use Pwr_SrfFillet :  
1) Select two or more intersecting surfaces that you wish to fillet.
2) Choose the fillet parameters and options   
3) Pick additional cutters.
4) Pick stock objects (stock objects will be cut up by the cutters).
5) Define the parts of the originals you wish to keep (Stock Outside Cutters, Stock Inside Cutters, Cutters Outside Stock).
6) You can then extract to an Editable Mesh and use the Explode option with 360 degrees to get separate objects to manipulate or animate.   

  Surface Filleting Size Parameters  

The EditableBrep object is a Power NURBS Object that has permanent sub-object history and can be edited in much the same way an Editable Mesh can be edited. 

Radius / Dist:  The fillet radius or chamfer distance
Blend Scale:  This value controls relative strength of the derivatives for the G1, G2 and G3 blending.  The values will typically range between 0.1 and 2.0 where 0.1 looks a lot like a chamfer and 2.0 nearly produces a sharp corner in the fillet.

Fillet Type
Choose the fillet type from the drop down list.  Choose between the following options.

Constant Radius:  Uniform radius fillet.  The cross section will have a uniform radius.
Constant Distance:  Used to create a chamfer
Variable Radius:  Variable radius fillet

Trimming Type
Choose the trimming type from the drop down list.  The trimming type determines how the surface fillet will be trimmed or extended at the ends of the fillets.  Choose between the following options.

No Trimming:  No trimming will be performed
Minimal Trim:  Trims back to the shortest distance along the fillet
Maximal Trim:  Extends to the maximum length along the fillet
Bevel Trim:  A linear bevel trim will be applied at the fillet ends
Blend Trim:  Creates a blended trim at the fillet ends

Cross Section Type
The Cross Section Type defines what kind of curve is created between the two rails of the fillet.  Normally fillets are created with either linear cross sections for chamfering or circular cross sections for standard mechanical fillet.  We have also added additional blend types and a Blend Scale so there is a greater control over the shape of the cross section of the fillet.

Circular Arc:  Fillet definition will be a circular arc
Non-Rational Arc:  Creates a fillet with a non-rational approximated arc
Linear:  Normally combined with the "Constant Distance" option to create a chamfer
G1 Blend Curve:  The G1 Blend Curve uses the first derivative of the adjacent faces to make the tangent direction continuous.  It blends the first derivative direction between two surfaces.
G2 Blend Curve:  The G2 Blend Curve uses the second derivative of the adjacent faces so that the radius of curvature is continuous across the boundary between the fillet surface and adjacent faces.  It blends 2 derivatives smoothly between two surfaces.
G3 Blend Curve:  The G3 Blend Curve uses the third derivative of the adjacent faces to make the rate of curvature change continuous across the boundaries.  It basically blends 3 derivatives smoothly between the two surfaces.

Medium:  Uses a tolerance with 5 digits of accuracy.
Low:  Uses a tolerance with 4 digits of accuracy.
High:  Uses a tolerance with 6 digits of accuracy.
Very Low:  Uses a tolerance with 3 digits of accuracy. 
Very High:  Use a tolerance with 7 digits of accuracy. 
Variable Radius Settings
These settings are used only with variable radius fillets.  You need to choose the "Variable Radius" type for fillet type in order for these settings to be used.  The "%" and "Rad" values are used to define the fillet radius and distance for each fillet cross section.  The "Add Pair" button is used to add cross sections, and the "Del Pair" button removes cross section definitions. The following procedure can be used to create variable radius surface fillets:

1) Select "Variable Radius" for the "Fillet Type" (see "Fillet Type" settings above)
2) Set the desired percent along the curve and radius for the start of the surface fillet (i.e. %: 0.0 and Rad: 10.0)
3) Hit "Add Pair" to have them added to the list box
4) Add the intermediate and ending "%" and "Rad" pairs.  Note that you should have a value at the end of the curve which will be 100%.  You can set this ending  value to 0 if you wish.
5) Use the "Pick Edges" button and select one or more edges to fillet.
6) Use the "Add Selected" to add those fillets and see the circles
7) Look at the circles put along the edge and determine if variable radius definition is in the correct orientation along the edge.
8) If it is not in the correct orientation, hit "Reverse" and "Add Selected" to flip the orientation.
9) Use "Show Fillets" to see the results.

%:  Defines the distance (as a percentage of the overall length) along the selected curve.  Not you must have a 0.0% and a 100.0% value entered.   
Rad:  Defines the radius of the fillet at the definition point
Add Pair:  Creates a fillet cross section definition at the point defined by the "%" value, using the radius defined by the "Rad" value.
Remove Pair:  Deletes the selected fillet definition
Reverse:  Reverses the order of the fillet definitions for the variable radius fillet so that you can adjust which end of the edge the variable radius starts on.
Blended Interpolation:  Uses a blended interpolation (instead of linear), for a smoother transition between fillet radii.  Makes fillet surface parallel to the edge at the point along a given edge.