Rhino Import/Export File Formats

To open, import, insert, and attach a file as a worksession

  1. From the File menu, click Open or Import.

  2. In the dialog box, the Files of type list displays the currently supported file types for import.

  3. Select the supported file type.

  4. In the File name box, select or type a file name.

  5. Click the Open button.

To save as or export a Rhino model

  1. From the File menu, click Export Selected or Save As.

  2. In the dialog box, the Files of type list displays the currently supported file types for export.

  3. In the Files of type box, select the supported file type.

  4. In the File name box, select or type a file name.

  5. If the file type has a specific format for the target software, select the format from the list.

  6. If the file type creates only mesh objects, in the Create mesh from NURBS object
    dialog box, specify the mesh settings

Index of Import/Export File Types

.3ds (3dstudio max)

.ai (Adobe Illustrator)

.asc (points)

.csv (points)

.csv (properties)

.dgn (MicroStation)

.dwg (AutoCAD)

.dxf (AutoCAD)

.fbx (Autodesk)

.gdf (WAMIT)

.gf (GHS – General Hydrostatics Geometry)

.gft (GHS – General Hydrostatics Geometry)

GHS (General Hydrostatics Geometry)

.gts (GNU Triangulated Surface)

.kml (Google Earth)

.lwo (LightWave 3D)

.obj (Wavefront)

.off (Geomview)

.pdf (Portable Document File)

.pm (GHS – General Hydrostatics Geometry)

.pov (Persistence of Vision Raytracer)

.ps (PostScript)

.raw (Raw Triangle)

.rib (RenderMan)

.sat (ACIS)

.skp (SketchUp)

.slc (Slice)

.step (Standard for the Exchange of Product Model Data)

.stl (Stereolithography)

.txt (points)

.udo (Moray)

.vda (Verband der Automobileindustrie)

.vrml (Virtual Reality Model Language)

.wmf (Windows Metafile)

.x (DirectX)

.x_t (Parasolid)

.xgl (Solaris)

.txt (points)

.3ds (3dstudio max)

File Exchange Steps


  • 3DS files contain polygon mesh objects. Polygon mesh objects import into Rhino as polygon mesh objects. They do not convert to NURBS

  • Rhino can read texture mapping coordinates
    from 3DS files.

  • 3D Studio export uses exact object names whenever possible.

  • If the object name in Rhino is: RhinoObjectName, 3DS export uses the first 10 characters of the name, because MAX and 3DS only support object names up to 10 characters. The result of this example is: RhinoObjec

  • Rhino then checks whether or not the object name has already been used. If so, the object name is truncated to 6 characters and a 3-digit index is added, like this: RhinoO_010 The index is the last three digits from the mesh counter used in the exporter.

  • If no object name is defined, Rhino uses a generic name: Obj_000010. In this case, the index is the last six digits from the mesh counter.

.ai (Adobe Illustrator)

File Exchange Steps

Import Options

Fit to default screen

Scales the objects to be visible in the default Top viewport.

Preserve units

Set the scale for conversion to Rhino units from inches in Adobe Illustrator.


  • Rhino cannot open AI 9.0 files. Save your file from Adobe Illustrator as a version 8 or older file format.

  • Rhino only reads curve geometry, not text. Convert text to curves before saving or exporting the Adobe Illustrator file.

Export Options


You cannot preserve the scale and units from a perspective viewport.

Snapshot of current view

Rhino exports the curves as a 2-D snapshot from the active viewport.

Preserve model scale

Sets the scale factor and units you want to use.


Export viewport boundary

Exports a rectangle that corresponds to the current viewport boundary. It is useful for registering curves to renderings or screen captures taken in the same view.


  • Before exporting, position the objects in the active viewport the way you want them to fit the page in the illustration program.

  • Rhino exports text and dimensions to AI files.

  • Rhino exports NURBS
    geometry and polygon meshes as wireframe curves.

  • Curves have fewer control points than the original because the Adobe Illustrator file format only supports non-rational cubic Bézier curves. Rational curves or curves higher than degree 3 are approximated with a cubic Bézier.

  • If you draw curves using the free-form curve tools degree 3 or lower and export them from the top view, they won’t get refit and will look exactly the same in Adobe Illustrator.

  • Hatches export into AI as closed paths with standard solid fills.

.csv (object properties)

Exports Rhino object properties to a comma-delimited file.

File Exchange Steps


Include header line

When exporting to a spreadsheet, a column heading line will be created.

Layer information

Layer name

Layer color

Layer index

Object information

Object name

Object ID

Object description

Object color

Object material

Mass properties



Area centroid

Area moments



Volume centroid

Volume moments

Cumulative mass properties

Note: Creates a comma-delimited text file in CSV (comma-separated value) that contains a tabulation of various object properties including layer name, layer color, object name, object render color and selected mass properties. The text file is created in a way that makes it easy to import information into spreadsheet programs like Microsoft Excel.

.csv/.asc/.txt/.xyz (Points)

File Exchange Steps

To open or import a point file:

  1. From the File menu, click Open or Import.

  2. In the dialog box, in the Files of type box, select Points File (*.asc; *.csv; *.txt; *.xyz).

  3. In the File name box, type a name for the file.

  4. Click Open.

  5. In the Points File Import Options dialog box, select the delimiter character and specify whether to create a point cloud
    object from the file.

  6. Click OK.

Note: Point files must be in the form: x,y,z with no additional heading information at the top. The characters can be separated with a variety of characters and can be surrounded by quotation marks.

To save point files:

  1. On the File menu, click Save As or  Export Selected.

  2. In the dialog box, in the Save as type box, select Points File (*.txt).

  3. In the File name box, type a name for the file.

  4. Click Save.

  5. In the Points File Export Options dialog box, select the delimiter character, number of significant digits of precision, and specify quotes.

  6. Click OK.




Separates values with commas.


Separates values with semicolons.


Separates values with spaces.

Separates values with a character you specify.


Significant digits

Rounds values to the number of significant digits you specify.

Surround values with double-quotes

Places double-quote marks around each value.

.dgn (MicroStation)

DGN is a file format common to Intergraph’s MicroStation and Interactive Graphics System (IGDS) CAD applications running on Intergraph workstations and PC’s.

File Exchange Steps

.dwg/.dxf (AutoCAD)

File Exchange Steps


AutoCAD version:

You can export as AutoCAD Release 12 or later.

Save curves as:

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.

If polycurves
with arc or line segments are saved as splines and simplify is on, Rhino will save arcs and lines. Otherwise, separate splines are saved.

Splines with kinks are never saved.

If polycurves with arc segments are saved as polylines and simplify is on, they are saved as bulge segments in the polyline. Otherwise, they are tessellated to small straight polyline segments.

If the Use simple entities checkbox is checked, arcs, circles, and lines are exported as AutoCAD arc, circle, and line entities.

3-D curves are never simplified.

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.


If you export curves as polylines, all curves are approximated with polylines before exporting. You can adjust the way polylines are created in the Curve options.


All curves are exported as AutoCAD spline entities.

Rhino curves will be exploded upon export if this option is turned on. Rhino polylines will translate 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.

Polygon meshes

If you export surfaces as meshes, the Create Mesh from NURBS object
dialog box lets you adjust the way Rhino creates the polygon meshes.


If you export surfaces as curves, Rhino exports the wireframe
as curves. Use the Write curves as setting to specify how these and other curves are exported.

Polyface meshes

Polygon meshes are exported as polyface meshes.

3D Faces

If you export polygon mesh objects as 3D Faces, each polygon in a polygon mesh is exported as a separate 3D Face.

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

Curve options:

Project to plane

Objects are projected to the active construction plane. They will appear on the world XY plane in the DWG/DXF file. Exporting this way does not automatically include silhouette lines.

For silhouette lines, see the Silhouette
and Make2D

Use simple entities

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.

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 shouldn’t 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.

Polyline max angle

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

The Polyline max 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.

Polyline 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.

Polyline seg 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.


  • Block definitions and instances are translated between Rhino and AutoCAD.

  • Block names in Rhino beginning with * are saved in AutoCAD beginning with _ (underscore).

  • AutoCAD line widths bylayer and byobject are read into Rhino plot widths By Layer and By Object.

  • Attributes are read from AutoCAD files and made into text in Rhino

  • Hatches from AutoCAD may not import in the same position relative to objects, because Rhino does not support varying the origin.

  • Importing ACIS objects from AutoCAD v2000 files is supported.

  • Importing ACIS solid objects in R13 or R14 DWG files is not supported. You can transfer NURBS
    geometry between AutoCAD and Rhino using IGES with the IGES import/export module. You can export Rhino geometry to AutoCAD using the ACIS SAT file format.

  • DWG files can contain polyface mesh and 3Dface entities. Polyface mesh and 3Dface entities import into Rhino as polygon mesh objects. They do not convert to NURBS.

  • Wide polylines are converted to Rhino surfaces. If the polylines are narrower than Rhino’s current tolerance setting, wide polylines will import as Rhino polylines.

  • Rhino will not import graphics, rays, regions, OLE objects, or anything in paperspace.

  • Rhino ignores AutoCAD line types.

  • Layer names and colors are preserved during import and export.

  • The lock status of layers in AutoCAD has no effect in Rhino.

  • Off and frozen layers import into Rhino as off layers.

  • XREF’s are imported, but XREF layers with the same names as the base drawing layers are merged. If any of the layers contributing to a merged layer is off or frozen in AutoCAD, the combined layer will be off in Rhino.

.fbx (Autodesk)

File Exchange Steps


  • Reads polygon meshes with associated materials and textures.

  • Poses, skeletons, and takes are not read because Rhino doesn’t have any way to represent them.

  • NURBS objects and patches are currently not imported.


  • Exports meshes with materials and textures.

.gdf (WAMIT)

File Exchange Steps

For more details: see www.wamit.com

.gf/.gft/.pm (GHS – General Hydrostatics Geometry)

GHS geometry files are used to analyze floating vessels (boats, ships, docks.

The GHS home page is http://www.ghsport.com/home.htm
. The specification for a GHS geometry file can be found at: http://www.ghsport.com/support/APPEND-A.HTM

File Exchange Steps




Import the data in the geometry file as a set of meshes

Body View

Generate 2-D body sections

Plan View

Generate a 2-D plan (top down) view

Profile View

Generate a 2-D profile (from side) view

Wire Frame

Generate 3-D polylines from data in the geometry file

Attach GHS Data to Meshes

Add GHS geometry file information to the meshes generated on import. This includes all of the hull and tank information (contents, permeability, sounding tubes&). This is the same information embedded with the AttachGHSData

This is an option only available with the Mesh import option. Using the other modes will contain only the geometry, not the GHS data.

Remove collinear points

Simplify imported polylines by removing collinear points. If three point along a station all lay on the same line, the middle point will be removed.

Note: When a GHS file is imported using the mesh option, it is possible that the mesh may not have the exactly correct join information. You can edit the mesh with the mesh editing commands.

Creating a GHS file is a two-step process:

  1. Use the AttachGHSData
    command to define portions of the hull.

  2. Use the SaveAs command to export data to a GHS file format.

  3. GHS Geometry Files (GF)

    Before saving a GHS Geometry file, GHS data needs to be associated the surfaces or meshes through the AttachGHSData

To save a GHS Geometry file

  • In the Save dialog box, select GHS Geometry File (*.gf).

GHS Part Maker File (PM)

A GHS Part Maker file is a script that is processed by the Part Maker application to create or modify a GHS geometry file. In many cases this is a better alternative than the straight GHS Geometry File export because the script can be modified with notepad to include additional geometric information.

To save GHS Part Maker Files (PM)

  • In the Save dialog box, select GHS Part Maker File (*.pm).

.gts (GNU Triangulated Surface)

File Exchange Steps

For more information see: http://gts.sourceforge.net

.kml  (Google Earth)

Creates a Google Earth .kml file that can be converted to a .kmz file by zipping and renaming form .ZIP to .kmz.

For details see: http://earth.google.com/kml/kml_intro.html

File Exchange Steps

Publishing .kml or .kmz files on your web site

Google Earth .kml and .kmz files can be published like an other web-compatible file type (.html, .jpg, .gif, etc.) but your web server needs to be aware of .kml and .kmz files. For details, see: http://www.keyhole.com/kml/kml_tut.html#kml_server

Tips for making Google Earth Models

  • Use the EarthAnchorPoint
    command to set the earth anchor point.

  • Work in a building-sized unit, like meters. (You can work in any unit system, but do not expect to be able to see a centimeter-sized earring in Google Earth.)

  • Set the Perspective view lens length
    to 21mm. This closely matches the camera angle used by Google Earth.

  • When you save the Google Earth file, make sure you are in a Perspective viewport looking at the object from above ground level.

  • Mesh
    complicated polysurfaces and keep the meshes fairly small.

  • The diffuse material color
    is what shows up in Google.

  • You can open, edit, and save KMZ and KML files with Google Earth to add additional features beyond 3-D geometry.

.lwo (LightWave 3D)

File Exchange Steps


  • Rhino imports line and point objects from LightWave.

  • Rhino breaks apart objects into separate meshes and sorts them into layers by surface type.

  • LightWave files contain polygon mesh objects. They are not converted to NURBS

To save LightWave files:

  1. On the File menu, click Save As or Export Selected.

  2. In the dialog box, in the Save as type box, select LightWave (.lwo).

  3. In the File name box, type a name for the LightWave file.

  4. Click Save.

  5. In the Create mesh from NURBS object
    dialog box, set the way Rhino creates a polygon mesh from the NURBS geometry.


  • LWO only exports mesh or meshable (surfaces
    , polysurfaces
    , etc.) objects, NOT curves
    , polylines, points
    , etc.

  • If exporting to a version of LightWave earlier than version 6, the LightWave file is limited to 65,535 points for the entire file. If you are using an earlier version of LightWave, you will need to export large Rhino models in pieces or export as OBJ file format
    , which does not have the 65,000 polygon limitation. This restriction does not apply to LightWave 6 or later.

  • Use the ExtractControlPolygon
    command to convert smooth Rhino surfaces into polygon meshes that you can convert into MetaNURBS objects in LightWave.

  • Object names will be used when exporting the LightWave file instead of a generic name.

.obj (Wavefront)

See also…

File Exchange Steps

OBJ Export Options

Export geometry as


Rhino curves and surfaces export as NURBS curves and surfaces.

Polygon mesh

Surfaces are approximated with polygon mesh objects. In the Create mesh from NURBS object
dialog box, set the way Rhino creates a polygon mesh from the NURBS geometry. Curves do not export.

Export trims as


When exporting NURBS surfaces, polylines approximate the trimming curves. The geometry does not match the accuracy of exporting trims as curves. This option was originally included for exporting to Alias. Now you should be able to use IGES for exporting to Alias instead.


When exporting NURBS surfaces, the trim curves are NURBS. NURBS trim curves provide more accuracy than exporting trims as polylines.

End of line character

CRLF (Windows, MS-DOS)

Return + line feed.

LF (Unix)

Line feed only.

CR (Mac OS)

Return only.

Export object names

Exports object names.

Export layer names

Exports layer names.

These settings make it possible to export data to programs that do not support nested grouping. The OBJ import plug-in for 3ds max is one example. To export to 3ds max, clear the Export layer names checkbox.

Export material definitions

Creates an .mtl file with the same name as the .obj file. The .mtl file contains one material definition per object. There are also references to these materials added to the .obj file.

Y Up

Translates the exported model from a z-up orientation to a y-up orientation.


  • Attempting to export invalid objects will cause the export to fail. Use the SelBadObjects
    command to find invalid objects before exporting.

  • Assign a material name to an object on the Properties window, Material
    page. This material name is exported for use by the renderer.

  • Layer names and object names export into the OBJ file as OBJ group names. Spaces in the layer or object names are converted into underbar (_) characters.

.off (Geomview)

File Exchange Steps

For more details: see www.geomview.org

.pdf (Portable Document File)

File Exchange Steps


  • Rhino does not read encrypted PDF files.

  • The PDF reader lets you read two types of files: PDF file and newer Adobe Illustrator files.

  • It is recommended for reading PDF files with graphics, but not for PDF files with a lot of text.

  • If the PDF file contain multiple pages, the PDF reader reads only the first page.

  • You can scale the objects to fit the default view.

.pov (Persistence of Vision Raytracer)

File Exchange Steps

For more information see: http://www.povray.org


.ps (PostScript)

Rhino does not have direct PostScript support.

To save PostScript files:

  • Print to a file using a PostScript printer driver.

To open PostScript files:

  • To open PostScript files, you need to use an illustration program to convert the PostScript file into Adobe Illustrator
    (.ai) format and then import the resulting file into Rhino.

.raw (Raw Triangle)

File Exchange Steps


  • RAW files contain polygon mesh objects that consist of triangular polygon faces only. All quadrangles are converted to triangles. They do not convert to NURBS

  • To break a polygon mesh into separate triangular faces, export it in .raw format, import it back into Rhino, and use the Explode

  • To break a polygon mesh into triangles and quadrangles, use .dxf

.rib (RenderMan)

File Exchange Steps


  • Rhino uses the active view for the RIB export. Make sure the correct view is active when you export.

  • Rhino spotlights are exported to RIB. The intensity is always set to 1, the beam distribution to 2 (these are shader defaults).

  • Assign a material name to an object on the Properties
    window, Material
    page. Rhino exports this material name for use by the renderer.

  • Object names are exported to make it easier to identify surfaces in the RIB file. Use the Properties
    command to set the object names.

  • A name attribute definition is inserted before each light.

  • The transparency color is the color of the object.

  • When rendered with default settings, a Rhino-compliant spotlight shader makes the RIB scenes look very close to Rhino scenes.

  • Rhino writes the surface, color, and opacity statement for each object. This makes it easier to parse the RIB file and replace the settings if necessary.

  • Exporting to the RIB file format does not replace the Rhino search paths, but rather appends the existing paths. This makes it possible to define custom search paths in .rendribrc.

  • Export to RIB file format supports render background color.

.sat (ACIS)

File Exchange Steps

To save SAT files:

  • In the ACIS SAT Detailed Export Options dialog box, select the options for the export.


  • There are various file types that save Rhino files as SAT files. All of the version types can export curves, but not all programs based on ACIS can import curves.

  • Hidden geometry is skipped when Rhino creates the SAT file.

  • For all of the AutoCAD products and for Mechanical Desktop:

  • Products read these curves, but import them in as bodies. To change these into splines, select

    the curves and explode them.

    These products will not export splines to an SAT file.

    These products do not fully implement ACIS file support. Some actions cannot be performed on imported NURBS

ACIS types


ACIS version: 4.0
curves are not exported
curve knots and surface knots are clamped
closed surfaces are split

ACIS Version 1.5

ACIS Version: 1.5
Exports curves
Curve knots and surface knots are clamped
Closed surfaces are split

ACIS Version 2.0

ACIS Version: 2.0
Exports curves
Curve knots and surface knots are clamped
Closed surfaces are split

ACIS Version 3.0

ACIS Version: 3.0
Exports curves
Curve knots and surface knots are clamped
Closed surfaces are split

ACIS Version 4.0

ACIS Version: 4.0
Exports curves
Curve knots and surface knots are clamped
Closed surfaces are split


ACIS Version: 4.0
Exports curves
Curve knots and surface knots are clamped
Closed surfaces are split

Mechanical Desktop

ACIS Version: 4.0
Exports curves
Curve knots and surface knots are clamped
Closed surfaces are split


ACIS Version: 4.0
Does not export curves
Curve knots and surface knots are clamped
Closed surfaces are split

Inventor does not read any ACIS object that is not a legitimate solid.


ACIS Version: 4.0
Does not export curves
Curve knots and surface knots are clamped
Closed surfaces are split

SolidWorks ignores anything that is not a surface or a solid.

.skp (SketchUp)

SKP is a file format used by SketchUp. For more information, see: www.sketchup.com

File Exchange Steps


Specifies how SketchUp geometry is read into Rhino. The options are stored between Rhino sessions.




Imports the objects as mesh faces.


Imports objects as planar trimmed NURBS surfaces.


Determines whether or not objects will be joined on import.


Joins objects.


Does not join objects.

Rhinoceros  ABlankButton Other File Formats

Rhinoceros Menu2 Other File Formats

Rhinoceros Gray Book Open Other File Formats Related topics…

.slc (Slice)

File Exchange Steps

To save SLC files:

  1. Pick a point that will be start of your slicing normal.

  2. The slices will be evenly spaced, (you can modify the distance between slices in an upcoming dialog box) and perpendicular to the slicing normal.

  3. Pick a point that will be the end of slicing normal.


Distance between slices

The distance between the slices or layers of curves that your final output will contain. The distance should be based on the slice thickness of your final output device. (For example, The ModelMaker II has slice thickness of 0.0127mm, 0.0254mm, 0.0381mm, 0.0508mm and 0.0762mm.)

Angle between polyline segments

The angle that determines how smooth the polylines of the slice curves will be. When the number is small you will get a smooth final output but it will take more time to export.

Use meshes to generate slices

The curves for each slice are generated by intersecting the object mesh with a plane. Consequently, the Angle between polyline segments data is no longer used. The final output is based on the number of polygons chosen for the mesh in the Polygon Mesh Options dialog. The greater the number of polygons, the longer it will take to export and the smoother the final result.

.step (Standard for the Exchange of Product Model Data)

File Exchange Steps

Note: Importing a model in a format that supports units and tolerances does not adjust the units and tolerances in Rhino. A dialog box will warn you if the units do not match.

To save STEP files:

  • In the Step Options dialog box, choose a STEP schema.

  • Your company standards determine which STEP schema you should use. If you have no standard, choose the default. The STEP schema number makes no difference to the data exported.


Browses the structure of a STEP file.


  • Select a file.

Rhinoceros  ABlankButton Other File Formats

Rhinoceros Menu2 Other File Formats

Rhinoceros Gray Book Open Other File Formats Related topics…

.stl (Stereolithography)

File Exchange Steps

Note: STL files contain polygon mesh objects. Polygon mesh objects import into Rhino as polygon mesh objects. They are not converted to NURBS

STL Mesh Export Options


The maximum distance between the original object and the polygon mesh created for the STL file.

Detailed Controls

STL Export Options

File type



Export open objects

Allows objects that are not fully closed to export. Do not use this option for rapid-prototyping machines.

If this checkbox is cleared, the STL file will not be created if there is an open object.

When the file does not export, the offending meshes/surfaces are selected. Use the ShowEdges
command to find the edges that need repair. Ideas for repairing the mesh


Adjust Mesh

Opens the STL Mesh Export Options dialog box.

STL mesh export diagnostics

For some rapid prototyping machines, STL files must contain completely closed (watertight) polygon mesh objects.

You might want to do this to ensure that the meshes really do fit together before exporting them for use in an expensive STL job.

Use the Join
command, then Weld
(angle=180), and UnifyMeshNormals
to turn a group of meshes into a single watertight mesh object. Then use SelNakedMeshEdgePt
to find the open (naked) edges.

To test for watertightness

  1. Join
    the mesh objects.

  2. Conceptually, this command gets all the triangles into one bag, but it doesn’t glue the edges together. (The situation is similar to having surfaces that all fit together but have not been joined into a solid.)

  3. Weld
    the new mesh object.

  4. At the Angle tolerance prompt type 180.

  5. An angle tolerance of 180 tells the Weld
    command to glue adjacent triangle points together no matter what.

  6. UnifyMeshNormals

  7. This changes all the triangles so they are oriented the same way, that is, if two triangles share an edge, then they have the same idea of up.

  8. To see if the result has any holes or gaps, type SelNakedMeshEdgePt

  9. If a mesh point is highlighted, then it is part of a “naked” triangle edge.

To avoid generating very large mesh files

A good procedure is to start with the Mesh
command, which has the same controls as the render mesh controls found in Document Properties. The difference is that the Mesh
command, however, produces a polygon mesh you can export. You would get the same controls by exporting the Rhino geometry to STL, but in general it is preferable to make the mesh object as a separate operation and export that.

The settings that work best for STL will vary, but a good place to start is to go to clear the Maximum Angle setting and the Maximum Aspect Ratio setting completely. Set the Maximum distance edge to surface setting (which is the desired maximum distance between the midpoint of any edge of a polygon and the true surface) to something around the resolution of the rapid prototyping machine. About .005 inch (.125mm) might be a good number to start with. It may be that once you have determined which are the best settings for your projects and rapid prototyping machine, this procedure may become superfluous. Instead you may just want to export the NURBS objects directly and use your proven mesh settings when the object is converted to polygons during export.

Once the mesh is generated, you can hide the NURBS object and inspect the mesh using the FlatShade
command. This will show you a shaded view of the polygons without the smoothing tricks used by normal shaded views. If the mesh looks good, export the mesh to the STL file. If not, delete the mesh and try different mesh settings.

It is best to only change one setting at a time to see the effects of that setting. If the mesh is fine enough but some areas do not work, try Maximum aspect ratio to something between 4 and 7. It is generally not worth setting Maximum distance edge to surface to much below the resolution of the rapid prototyping machine.

STL Mesh Export Options

Sets the mesh conversion options for STL export.

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Set the maximum allowable distance in model units between the original surface or solid and the midpoints of the polygon edges of the mesh being exported to STL.


Preview the mesh.

Detailed Controls

Opens the Polygon Mesh Detailed Options
dialog box to allow custom settings.


  • Changing settings on this dialog box affects the settings on the Polygon Mesh Detailed Options
    dialog box.

-Save or Export <filename.stl>



.udo (Moray UDO)

File Exchange Steps


  • Moray supports object names. Moray UDO export uses the first 40 characters of a string layer_name_object_name. The 40-character limitation is defined in the POV-Ray specifications. If multiple objects share one name, Moray UDO automatically numbers the objects.

  • Use this format if you want to define POV-Ray textures, and if you want to set other POV -Ray specific information in Moray UDO. Moray UDO is a shareware wireframe modeler available from http://www.stmuc.com/moray/

  • When you export to Moray UDO, Rhino creates a .udo file and a .inc file. Exporting the .udo file to &\Moray For Windows\PovScn\ folder seems to help you avoid the hassle of having to move the .inc file before rendering.

  • To import the object into Moray UDO, from the Moray Create menu, click User Defined.

  • The wireframe view in Moray UDO is a line approximation of the wireframe you see in Rhino.

.vda (Verband der Automobileindustrie)

File Exchange Steps

VDA is a neutral file format defined by German association of automobile industries consortium for exchange of CAD data across systems.

VDAFS file supports representation of 3 D geometry and topology information. It does not support representation of drawing information, symbols, views, etc. It does not support assembly and feature information.


Sender data

Sending company

Sender’s name

Telephone number


Part data

Project name

Object code



Date effective

Receiver data

Company name

Receiving department

Export PointDeviation hairs as MDI


.vrml (Virtual Reality Model Language)

File Exchange Steps


  • Rhino imports only VRML 2 files, but it can export both VRML 1 and VRML 2 files.

  • Rhino exports VRML files with the camera looking down the world z-axis toward the x,y-plane. This is the default Top view in Rhino.

  • Render color, shine, and transparency determine the render material properties exported to the VRML file.

  • The render background color exports as a background color to VMRL2.

  • Spotlights, point lights and directional lights import and export.

  • Texture assignments are currently not exported.

  • Assign a material name to an object on the Properties window, Material
    page. Rhino exports this material name.

  • Some VRML
    clients are incompatible with the material shininess (specularity) set to zero. Using Cortona and Cosmo Player, objects with shininess set to zero shade completely white. If the shininess is zero, Rhino sets the shininess to something bigger than zero (we used 1, but the value does not matter) and the specular color to black. The Black specular color results in a matte surface in the VRML viewer.



Choose between version 1.0 and 2.0. Try 2.0 first. If it does not work with your VRML viewer, try 1.0.

Vertex normals

Only the polygon mesh vertex normals calculated from the NURBS surfaces export to the VRML file. This may improve the appearance of the objects in the viewer, and it will make the file much larger.

Texture coordinates

The uv texture mapping coordinates are exported to the VRML file.

.wmf (Windows Metafile)

File Exchange Steps




Output Color

Print Color

Display Color

Black and White


See Print
command for other options.



  • Rhino exports the curves as a 2-D snapshot from the active viewport.

  • Rhino exports surfaces and solids as a polyline wireframe and curves as polylines.

.x (DirectX)

Note: Rhino does not directly support the DirectX file format.

To export a DirectX file:

  1. Export a 3D Studio 3DS file
    from Rhino.

  2. Convert the 3DS file into a DirectX file with conv3ds.exe, a utility that comes with DirectX SDK.


conv3ds -h yourfile.3ds

Note: You must use the -h option with conv3ds, because Rhino does not export key frame information to the 3DS file. Failing to use this option with Rhino 3DS files will crash conv3ds.

.x_t (Parasolid)

File Exchange Steps


  • Parasolid files are always in meters. If Rhino units are set to a real-world unit other than meters, the exported geometry will be scaled by the appropriate factor.

  • In general, your model’s objects should be joined solids that have no naked edges. Use the Properties
    command to ensure your models are closed solids, and the ShowEdges
    command to ensure there are no naked edges.

  • Simple planes are supported as Parasolid primitives. A simple plane is one that is defined in Rhino as four control points arranged in a rectangle. Planes are important primitives. Many feature-based modelers (SolidWorks in particular) only allow sketching on planar surfaces defined by a plane primitive.

  • To import files containing open surfaces, you must make a new part or import into an existing part model. Then choose the Insert > Surface > Imported & command and choose the exported file.

.xgl (Solaris)

File Exchange Steps

The XGL library is the Solaris foundation geometry library that provides the functionality and performance required by applications requiring geometry manipulation and display.

For more information, see: The Wikipedia article on XGL





Other File Formats