Exporting for printing
Shack CAD exports STL and 3MF meshes in millimetres, tessellated from the exact solids at the moment of export. Standard resolution is free. High resolution is a one-time purchase.
Exporting
- Press Export in the tool rail, or choose File ▸ Export for Printing… (⇧⌘E).
- Choose the Format: STL (binary) or 3MF.
- Choose what to Include. By default every visible body is exported; turn on Selected bodies only to export just the selection.
- Choose the Resolution.
- Read the Summary, then press Export… and choose where to save.
The export is complete when the file has been written. Pressing Cancel in the save dialog writes nothing.
Hidden bodies are never exported. A body that last failed to build and is showing its previous shape is never written either: the export is refused until the body builds again.
Formats
| STL (binary) | 3MF | |
|---|---|---|
| Units | None recorded. Coordinates are written in millimetres. | Millimetres, recorded in the file. |
| Bodies | All included bodies in a single mesh | Each body as a separate named object |
| Colours and materials | Not included | Not included |
STL has no unit field. Check that your slicer reads the file as millimetres; if a part arrives 25.4 times too small or too large, the slicer has assumed inches.
Body names are carried into a 3MF file, so it is worth naming bodies before you export.
Resolution
Curved surfaces are approximated by flat triangles. The resolution sets how far a triangle may sit from the true surface, which is called the chord tolerance.
| Resolution | Requested chord tolerance | Price |
|---|---|---|
| Standard | 0.150 mm | Free |
| High resolution | 0.020 mm | One-time purchase |
These values are what the mesher is asked for. They are requests, not independently measured maximum errors in the finished mesh.
Both settings export the same model with the same dimensions. High resolution re-tessellates every curve with finer triangles, which gives smoother curved surfaces and larger files. Standard resolution produces printable geometry; it is not a reduced preview.
A very large radius can reach the limit on how many segments a curve may have. The export sheet then shows the tolerance it can actually achieve, and asks you to accept it with Export at the achievable tolerance rather than exporting silently at a coarser setting.
The summary
Before you export, the sheet shows:
- File units: always millimetres;
- Geometry: exact solids, tessellated for this export;
- Triangles and File size for the file it will write;
- any mesh problem it measured, or a note that none was found.
A closed, correctly wound mesh is necessary for a dependable print, but it is not a guarantee. Slicer settings, material and your printer still decide the result.
High resolution export
High resolution is the only paid feature in Shack CAD. It is a one-time purchase made through the App Store and tied to your Apple Account.
- To buy it, choose Unlock high resolution… in the export sheet, or Help ▸ High-Resolution Export… Your format, scope and resolution choices in the export sheet are kept.
- If you have bought it before, on this Mac or another, use Restore purchases on the same sheet.
Modelling, saving, and Standard resolution STL and 3MF export are always free.