No elements in volume error on stl files
I have been trying to make a mesh for finite analysis from a set of CAD components representing a few sections of a spine(https://zenodo.org/record/3715368#.X-kiMDSSmUk under STL files), but have continually run into an error stating "no elements in volume" when I try to generate the 3d mesh.
To make the mesh, I have a python scripts that merges and makes a volume of each component of this model, generating the 3d mesh at the end. I don't think there are issues with the file itself, as it has been successfully used many times for mesh generation in simpleware, but I cannot figure out what I am doing wrong to generate these meshes.
Any tips? Thank you for the help.