Offsetsrf Failure On Complex Polysurface

This Result can be caused by various issues with the source file. Adjust the geometry in the file and try the import process again'). Only after significantly splitting or deleting control points down to a small portion can I get this object to import. I've sucessfully imported similar, but more complex surfaces from the same Rhino file into Revit. It only operates on solid, manifold polysurfaces. Selected polysurface faces are removed, the remaining faces are offset inward, and the inner and outer parts are joined. OffsetSrf - works on polysurfaces and solids. Options for round or sharp corners.

Offsetsrf Failure On Complex Polysurface Work
Offsetsrf Failure On Complex Polysurface Symptoms

Toolbar	Menu
Solid Surface Offset Surface

Toolbar

Solid

Surface

Offset Surface

The OffsetSrf command copies a surface or polysurface so that locations on the copied surface are the same specified distance from the original surface.

Steps

Select a surface or polysurface.

Infinite Plane: Type IP for InfinitePlane options.

Type the offset distance, and press Enter.

Offsetsrf failure on complex polysurface examples

Command-line options
Distance	Sets the offset distance.
Corner	Specifies how offset corner continuity handled. These options only apply if the offset direction is to the 'outside' as shown in the image. Sharp Curves offset to the outside of a corner will be extended to meet at sharp corners with position (G0) continuity. Round Curves offset to the outside of a corner will be filled with arc segments with tangent (G1) continuity.
FlipAll	Flips the offset direction of all selected surfaces. Arrows indicate the positive offset direction. Note: This option is not available when any of the selected objects is a polysurface.
Tolerance	Sets the tolerance for the offset surface. Type 0 to use the default tolerance.
BothSides	Draws the offset on both sides of the original.
DeleteInput	Yes Deletes the original geometry. No Retains the original geometry.

Note

Positive values offset in the direction of the arrows. Negative values offset the other way.
When a plane, torus, sphere, open cylinder, or open cone surface is offset, the resulting surface is exact. Free-form surfaces are offset to within the value of the Tolerance option.
When offsetting a polysurface with free-form sub-surfaces, the results might have some surfaces missing.
The output object adopts the rendering material from the input object.

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Solid Tools Solids Sidebar

Command-line options
Thickness	Specifies the thickness for the shell.

Singular surfaces can cause problems, especially when the offset of the surface must be extended at the singularity. The extensions are done in OffsetSrf (Corner=Sharp) and shelling, which always uses sharp corners. These extensions happen when the offsets of adjacent surfaces come apart. Also, cone-like singularities cause problems in all cases.
Complex vertices (ones with more than three edges) can be problematic, especially in shelling and sharp corner offsets and where some, but not all, of the surfaces at the vertex offset apart.
OffsetSrf on polysurfaces with naked edges, where the naked edges make concave boundaries will not work correctly.
If faces adjacent to the removed faces offset in such a way that the removed face must be extended to fill in the gap, it will fail.
Any surface whose offset self-intersects will cause a problem.