Make2D and DWG/DXF Export in Rhino 8: An Architectural Drawing Guide

This guide is based on McNeel’s Rhino 8 help documentation for Make2D and AcadSchemes. Make2D creates one- or four-view planar drawings from the edges and silhouettes of selected objects; AcadSchemes manages DWG/DXF export settings. The steps below help you evaluate options for your workflow when preparing line drawings in Rhino 8 and exporting them to another CAD application. Since the documentation does not prescribe a single settings profile for every project, choose options based on the drawing content and delivery requirements.

1. Choose the Make2D view and projection

Select the objects to convert into a drawing and run the Make2D command. For a single-view output, the View option uses the active view. The default output location is also based on that view: its lower-left corner is placed at the World origin.

Use the CPlane option to create a drawing from the active viewport’s plan view and place the result on that viewport’s construction plane. If you want to maintain alignment with a previous output, Register with previous attempts to match a previously saved view. This option works only with the View and CPlane projections.

For a four-view drawing, there are two layout options:

• First angle projection creates a European-style first-angle layout.

• Third angle projection creates a US-style third-angle layout.

These options use orthographic projection relative to world coordinates; they do not follow the view or construction plane direction of the active viewports. So assess the orientation of a four-view output separately from the on-screen viewport layout.

When using Register with previous, changes to a perspective viewport can disrupt the match. If Rhino cannot find a match, it may save the current view for later use. If alignment differs from what you expect after changing a view, consider turning off the registration option and working with a new view.

2. Choose line content and output layers

Make2D options determine which lines are generated and where their properties come from. Hidden lines creates hidden lines on the specified Hidden layers. Tangent edges adds tangent edges of polysurface objects; Scene silhouette adds object silhouettes with a heavier line weight. The Clipping plane intersections option adds lines where clipping planes intersect objects.

Choose Object properties to inherit output properties from source objects, or By output layers to assign them according to the output layers. Layer name specifies the main layer for the 2D drawing; different curve types are organized in sublayers. Group output groups curves by source object. In perspective views, Viewport rectangle creates a rectangle showing the viewport boundary.

The table summarizes the documented options; the sources do not recommend fixed values for these settings for every drawing.

3. Configure a DWG/DXF export scheme

After preparing the drawing output, you can use the AcadSchemes command to configure an AutoCAD export scheme. Schemes let you save and reuse DWG and DXF export settings. The Rhino 8 documentation lists Lines, Natural, Polylines and Solids options for versions such as 2007, 2010, 2013 and 2018. It notes that you may need to test settings to get good results in the target application.

AutoCAD version determines the version of the file to export. In R12 DWG/DXF exports, curves are approximated using polylines. R13/R14/2000 and later formats can use polyline or spline entities. If the Rhino model consists mostly of polylines, this export type may be worth considering; if you want to preserve the actual curvature of non-composite curves, consider the spline option. Note that Simplify lines & arcs must be turned off to export splines.

Choose the surface export type based on what the target application expects. Solids exports simple solids as 3DSolids in SAT format. Curves exports wireframe geometry as curves; Meshes exports surfaces as polyface meshes. Meshes can also be exported as 3DFaces; with this option, each mesh face becomes a separate 3DFace. According to the documentation, some programs that read DXF can read 3DFaces but may not handle polyface meshes correctly.

In the scheme settings, you can also choose whether layer names are written with their full paths or only the sublayer name, and whether colors are exported as RGB or AutoCAD Color Index (ACI). Conversion from RGB to ACI is limited to a 255-color palette; colors outside the palette may be exported using approximate matches. So check the layer structure and color appearance as part of the drawing delivery process.

4. Evaluate polyline settings against model scale

When curves are exported as polylines, the Maximum angle, Chord height and Segment length options affect how closely the polyline follows the curve. Maximum angle sets the largest angle between adjacent polyline segments. As the value increases, segment midpoints may deviate further from the original curve.

Chord height limits the distance between a segment’s midpoint and the curve. A smaller value gives a closer approximation but increases the number of segments. Segment length sets the maximum length of polyline segments in model units.

Setting the segment length too low without considering the model’s size can create excessive geometry and large files. In an example in the Rhino documentation, a maximum segment length of 0.01 on a model 100,000 units long could produce millions of segments. Evaluate the settings against the model scale and the curve fidelity required by the drawing.

Common mistakes

• Don’t assume Make2D will automatically create the intersection line between two objects that pass through one another. If you need that line, create it with the Intersect command and include it among the objects used for the drawing.

• Don’t assume Register with previous will preserve alignment when you change a perspective view; check the result.

• Don’t arbitrarily reduce segment settings in pursuit of better curve fidelity. This can increase file size.

• After a DWG/DXF export, don’t stop at checking that the file was created; also verify how the curves, meshes, layers and colors appear in the target application.

Impact on architectural and visualization workflows

These steps help architects, interior designers and visualization teams create line drawings from Rhino models and deliver them as DWG/DXF files. View and line options determine the drawing’s content, while layer and property choices shape the output’s organization. The sources do not specify special hardware requirements for these commands; in practice, curve types, file complexity and compatibility with the target software should all be considered.

Saving a scheme can be useful for reusing the same export settings across an office. Still, don’t assume the settings will produce the same result for every file: model scale and geometry types can vary. Test Make2D and DWG/DXF export on a representative section first, then check the views, layers and how the file opens in the target application. This can help catch issues before processing the full model.