How do I export a 3D model from Aspire as an STL or OBJ for use in other software or 3D printing?

Export Options at a Glance

Applies to: Aspire 12.5 only. Export as STL is not in the VCarve Pro manual.

• STL: an industry-standard mesh of triangles, a robust way to send your 3D composite model to external applications or rapid prototyping (3D printing) machines
• OBJ: another mesh format that includes the component colors and is mainly used for ray-traced rendering. Saving an OBJ also creates a material (.mtl) file and a texture image (.jpg) file, and all three are needed when opening it in other software
• POV-Ray scene (.POV): a third mesh format offered in the save dialog
• .3DClip: the Model menu's Export as 3D Clipart exports the selected model as a .3DClip file, for reusable component libraries
• Grayscale bitmap: the Model menu also has Export as Grayscale Bitmap

Exporting an STL or OBJ

1. Open the Model menu and choose Export as STL. The triangulation form opens
2. Under Limit Triangles By, choose how the mesh is simplified:

• Approximate tolerance: quality is set by how closely the mesh may approximate the model. A smaller number gives more detail and smoothness but a larger file
• Maximum number of triangles: quality is limited by the number of triangles you enter. A larger number gives more detail but a larger file

3. Choose a Back face of triangulation option (see below)
4. Click Triangulate. The software calculates the mesh and shows it in the 3D view. If it does not look detailed enough, change the options and click Triangulate again
5. Check Num Tri Created (the triangle count) and Maximum Error (the worst deviation of a triangle from the original model), and use Draw shaded triangulation to switch between wireframe and shaded views
6. Click Save Triangulation.... The file saves as STL by default, and the Save as type list also offers Wavefront (.obj) and POV-Ray Scene (.POV)

The export is of the composite model (all visible components combined), so hide anything you do not want in the file before you start.

Back Face Options

The composite model has no back face, because 3-axis CNC machining does not need one. For a closed mesh you can have one created:

• Leave Open (No Back Face): a shell with the 3D shape on its face and an open back
• Close with inverted front: puts a copy of the front on the back, for a solid two-sided model (for example a two-sided fish)
• Close with a flat plane: seals the back with a flat plane. This type of closed model may be required by 3D printing software to prepare the part for printing
• Close with other side (two-sided jobs only): triangulates both sides of a two-sided job into a single closed mesh
• Close sides (rotary jobs only): puts caps on the ends of the mesh

Rotary Models

When exporting a rotary model there is no control over the number of triangles. The mesh is exported at the highest quality, so the file can be very large. Close with inverted front, flat plane and other side are not available for rotary models, and Leave Open gives a mesh without end caps.

For 3D Printing

Aspire builds relief models (height maps). For printing, use Close with a flat plane to get a sealed back, then check the mesh in your 3D printing software before slicing, since each program has its own requirements for a printable mesh.