I was having a load of problems getting GUI based tools to scale down a large STL file for printing. If you’re a fan of command line tools to you might want to check out AdMesh.
- Read and write binary and ASCII STL files
- Check STL files for flaws (i.e. unconnected facets, bad normals)
- Repair facets by connecting nearby facets that are within a given tolerance
- Fill holes in the mesh by adding facets.
- Repair normal directions (i.e. facets should be CCW)
- Repair normal values (i.e. should be perpendicular to facet with length=1)
- Remove degenerate facets (i.e. facets with 2 or more vertices equal)
- Translate in x, y, and z directions
- Rotate about the x, y, and z axes
- Mirror about the xy, yz, and xz planes
- Scale the part by a factor
- Merge 2 STL files into one
- Write an OFF file
- Write a VRML file
- Write a DXF file
- Calculate the volume of a part
https://github.com/admesh/admesh