Para poder imprimir un modelo en una impresora 3D es necesario generar antes el formato STL correspondiente. STL (de estereolitografía) es un formato de fichero que prácticamente todos los programas de control de impresoras 3D aceptan.

Muchos, sin embargo, hemos tenido problemas a la hora de generar estos ficheros partiendo de nuestro diseño y luego, al imprimirlos en 3D, el resultado no ha sido el deseado.

La siguiente guía debería ayudaros a resolver estos problemas y obtener ficheros STL perfectos, listos para enviar a vuestra impresora 3D.

  • File > Save As

  • Set Save As Type to STL

  • Options > Fine > OK

  • Save

  • STL settings: How to change STL settings

  • File > Save As

  • STL > Options

  • For a smoother STL file, change the Resolution to Custom

  • Change the deviation to 0.0005in (0.004 mm)

  • Change the angle to 5 (Smaller deviations and angles will produce a smoother file, but the file size will get larger)


  • File > Export > Model

  • STL

  • Set chord height to 0. The field will be replaced by minimum acceptable value.

  • Set Angle Control to 1

  • OK

  • Richt Click on the part

  • Part properties > Rendering

  • Set Facet Surface smoothing to 150

  • File > Export

  • Choose .STL

  • File > Export > Rapid Prototyping

  • Output type : Binary

  • Triangle & Adjacency Tolerance: 0.015 mm

  • Set Auto normal Gen to ON

  • Set Normal Display to ON

  • Set Triangle Display to ON

  • File Header Information: Press OK

  • In case a error messages “Negative coordinates found” appears, it can be ignored

Solid Edge
  • Open Model & select File > Save As

  • Select File type as STL

  • Options > conversion tolerance to 0.015 mm

  • Surface Plane Angle > 45°

  • Select Binary type and OK

  • Name & Save STL file

AutoDesk Inventor
  • Go to the File menu, then select the ‘Save Copy As’ option

  • Select STL from the Types drop-down

  • Click the Options button, and choose the High detail level

  • Click the Save Button

3D Studio MAX 3D
  • File > Export>

  • Select “StereoLitho [*.STL]” in

  • Select location

  • Enter a name

  • Save

  • OK

  • Export To STL dialog

  • Object Name: Enter a name for the object you want to save in STL format.

  • Binary/ASCII: Choose whether the STL output file will be binary or ASCII (character) data. ASCII STL files are much larger than binary STL files.

  • Selected Only: Exports only objects that you selected in the 3D Studio scene.

  • File > Export…

  • Save As > STL…

  • Enter File Name

  • Save

  • Set DISPSILH to 1

  • Set ISOLINES to 0

  • Set FACETRES to 10

  • Relocate the object to the positive X-Y-Z octant

  • Use the STLOUT command to export a .stl file. (AMSTLOUT for AutoCAD Desktop files)

  • File> Export > STL

  • Enter Filename

  • Select Location

  • Click button Export STL

  • File > Export > STL

  • Type in a filename and select OK

  • Change Format to Binary

  • Use default Facet Tolerance

  • Additional export tolerance options are in the Solids99 Configuration window accessed from the Tolerance section of Configuration.


To export a complete assembly as a single .stl files, you will have to convert the assembly in the Assembly Design environment to a CATPart as follows

  • Select the entire product tree

  • Tools >Generate CATPart from product

  • Enter a new part number or name

  • Do NOT check: merge all bodies of each part in one body

  • OKYou will now be able to export the CATPart in the Part Design EnvironmentThe accuracy of the .stl file is a fuction of the Display accuracy.

  • Tools > Options…

  • In the tree select General > Display

  • Select the Performance tab

  • Under 3D accuracy, select Fixed

  • Set to .02mm (.0008in)

  • Adjust Curve accuracy ration to .2

  • OK

  • File > Save As

  • Enter filename

  • Select type STL

  • Save

Google Sketchup

Google Sketchup cannot currently export .STL files without installing additional plug-ins. A simple Google search will find some. Alternatively, you can export the files to .dae format and use an open source software such as Blender to export that file to .stl format.

  • File > Export > Rapid Prototype File > OK

  • Select the part to be prototyped

  • Select prototype device > SLA500.dat > OK

  • Set absolute facet deviation to 0.000395

  • Select Binary > OK

  • File > Save as > Save Copy as…

  • Select STL

  • Enter Filename

  • Click the Options button

  • Format Binary

  • Select units

  • Resolution > medium or high

  • Click the Save button

Iron CAD
  • Select Part Properties then Rendering

  • Set Facet Surface Smoothing to 150

  • Select File then Export

  • Select .STL

Mechanical Desktop
  • Use the AMSTLOUT command to export your STL file.

  • The following command line options affect the quality of the STL and should be adjusted to produce an acceptable file.

  • Angular Tolerance – This command limits the angle between the normals of adjacent triangles. The default setting is 15 degrees. Reducing the angle will increase the resolution of the STL file.

  • Aspect Ratio – This setting controls the Height/Width ratio of the facets. A setting of 1 would mean the height of a facet is no greater than its width. The default setting is 0, ignored.

  • Surface Tolerance – This setting controls the greatest distance between the edge of a facet and the actual geometry. A setting of 0.0000 causes this option to be ignored.

  • Vertex Spacing – This option controls the length of the edge of a facet. The

  • Default setting is 0.0000, ignored

Pro Engineer
  • File > Export > Model

  • STL

  • Set chord height to 0. The field will be replaced by minimum acceptable value.

  • Set Angle Control to 1

  • OK


Revit does not allow direct export to STL files but does allow to first save as .dwg file and open in AutoCAD to create .stl files.

  • 3D view

  • File menu > Export CAD format > select 3D polymesh

  • Save as Type > AutoCAD 2004 DWG

Now open the saved file AUTO CAD

  • Command menu > Explode

  • Select the object(s)

  • All the objects are converted into 3D solid

  • Select a single solid for STL output

  • Command menu > STOUT or Export

  • Select objects

  • Create a binary STL file

Alternatively, download the .stl Exporter from Autodesk Labs and follow the steps below.

  • Unzip and install it

  • Load a 3D model

  • External tool > export

  • Adjust the scale of the model appropriatelyHow to export a .stl from Rhino 3D CAD software

  • File > Save As

  • Select File Type > STL

  • Enter a name for the STL file

  • Save

  • Select Binary STL Files

Think 3
  • File > Save As

  • Set Save As Type to STL

  • Save

Unigraphics (now called NX)
  • File > Export > Rapid Prototyping or STL

  • Set Output type to Binary

  • Set Triangle Tolerance to 0.025mm or .001 in

  • Set Adjacency Tolerance to 0.1mm or .04 in

  • Set Auto Normal Gen to On

  • Set Normal Display to Off

  • Set Triangle Display to On