The AcadSchemes command creates AutoCAD export schemes, which determine how various Rhino objects are exported to AutoCAD .dwg and .dxf files.

Note: These options can be saved as schemes for later use. Several schemes that have been determined to give good results are available on the Export Scheme list. You may have to experiment with the options to get the best result from your downstream application.

AutoCAD Export Schemes


Select the export scheme to edit.


2004 Lines

2004 Natural

2004 Polylines

2004 Solids

CAM Imperial

CAM Metric

R12 Lines & Arcs

R12 Natural

General Options

AutoCAD version

When exporting curves to R12 DWG/DXF, curves are approximated with polylines. When exporting to R13/R14/2000+ DWG/DXF, you can export either polyline or spline entities.

Release 12

Release 14

Release 2000

Release 2004

Entities only

AutoCAD Release 12 DXF only.

Export surfaces as


Simple solids export to AutoCAD as 3DSolids (SAT).


The wireframe is exported as curves. Use settings on the Curves tab to specify how these and other curves are exported.


Surfaces are exported as polyface meshes.

Use the Create Mesh from NURBS object dialog box to adjust the mesh settings.

Export meshes as


Export meshes without modification.


Each face in a polygon mesh is exported as a separate 3DFace.

Some programs that read DXF files may read 3DFaces, but may not properly read polyface meshes.

Project to plane

Project objects to the active construction plane or the active view plane. Objects will appear on the world xy plane in the DWG/DXF file. Projecting does not automatically include silhouette lines.

For silhouette lines, see the Silhouette and Make2D commands.

Do not project

Objects are not projected.


Project to the active construction plane.


Project to the active view plane.

Export full layer paths (Parent$Child)

Export layer names only (Child)

Color by RGB

Exports colors as red, green, blue (RGB) values.

Color by AutoCAD index

Exports colors to match the AutoCAD color index.

Preserve arc normals

Keeps arc normals in their current orientation.

Flip arc normals to +Z

Flips arc normals to be mostly in the + direction of the closest world xyz coordinate.

Curves options

Rhino Objects

AutoCAD Objects











Polylines w/bulge arcs
















Polylines w/bulge arcs


AutoCAD Objects


All curves are approximated with polylines before exporting. You can adjust the way polylines are created in the Curve tessellation parameters.

3D Polylines

Each point on the polyline can have a different z-value.

Polylines w/bulge arcs

If polycurves with arc segments are saved as Polylines and Simplify lines and arcs is checked, they are saved as bulge segments in the polyline. Otherwise, they are tessellated to small straight polyline segments.


Exporting Rhino curves as AutoCAD splines is not an option when the AutoCAD version is Release 12.
All curves are exported as AutoCAD spline entities.
Rhino curves will be exploded upon export. Rhino polylines will export as multiple separate AutoCAD linear splines. Other Rhino compound curves will translate as separate splines.
If you have mostly Rhino polylines, you will probably want to export curves as polylines. If you have mostly non-compound curves and want to have real curvature in AutoCAD, export curves as splines.

Curve tessellation parameters

Maximum angle

When exporting curves as polylines, Rhino must approximate each curve with a polyline. The Maximum angle setting, combined with the Chord height and Segment length settings, determine how the polylines are created.

The Maximum angle option sets the maximum angle between adjacent polyline segments. The larger this number, the farther away the polyline segment midpoints are from the original curve.

Chord height

The distance from the polyline segment midpoint to the curve will be less or equal to this number. Smaller numbers make the polyline fit the curve better, but they also increase the number of polyline segments.

Segment length

The maximum length of a polyline segment. This setting uses current model units and ensures that all polyline segments are shorter than this setting.

The physical size of the model should be taken into consideration when using this setting exporting a boat that is 100,000 units long with a maximum segment length of 0.01 will result in millions of polyline segments and a huge DWG/DXF file.

Explode polycurves

Splits polycurves into separate splines at polycurve segment start/end points.

Split curves at kinks

Splits curves into separate splines at kinks.

Simplify lines & arcs

Circles, arcs, ellipses, and lines export as AutoCAD circle, arc, ellipse, and line entities.
Rhino compares each curve with an exact arc, circle, line, and ellipse and determines if it can be exported as a simple entity. If the curve is within the simplify tolerance of one of the simple entities, it is exported as a simple entity.
2-D curves are simplified. This means if the curve is just one line, arc, or circle, it is exported as an AutoCAD line, arc, or circle. If there are arcs in the curve with discontinuous curvature at the ends, it is exported as a bulge arc in a polyline.
3-D curves are never simplified.
If polycurves with arc or line segments are saved as splines, Rhino will save arcs and lines. Otherwise, separate splines are saved.

Simplify tolerance

Rhino must evaluate each curve to determine if it is a simple entity. If a curve is within simplify tolerance of an arc, line, circle, or ellipse, it will be exported as such.
If the simplify tolerance is too large, some curves may export as simple entities when they should not be.
If the simplify tolerance is too small, some curves may export as simple entities when they should be.
The default simplify tolerance should work well for most cases.


Create a new scheme.


Save the currently selected scheme.


Save the currently selected scheme with a new name.


Delete the currently selected scheme.


Rename the currently selected scheme.


Export the settings to a scheme file.


Import the settings from a scheme file.


Close the AutoCAD Export Schemes dialog box.

See also

AutoCAD (.dwg; .dxf; .dwf) Import/Export

Rhinoceros 5 © 2010-2015 Robert McNeel & Associates. 17-Sep-2015