Hi Ryan,
Meshing STL based files is possible but more difficult with Cubit. If you want nodes that match you need to be able to “merge” the surfaces in Cubit. This requires that the topology (the curves and vertices of the surfaces) match up exactly. With CAD based geometry we have an imprint tool that helps with this process. That automatic capability is not available for facet based models, like STL.
You can use the “Geometry/Surface/Modify/Partition” to add a curve onto a surface manually. This may work if you don’t have too many merged surfaces that you need to create.
Areas that are not merged will create duplicate nodes at adjacent surfaces and may be used to define contact or other physics between the adjacent surfaces.
While Cubit can be used to cleanup STL geometry, there are better tools out there. See the beginning this post Sculpt Workflow Suggestion - Coreform Cubit - Coreform LLC for some suggestions.
The sculpt mesher may also be an option if you don’t need to retain sharp features. That post also describes sculpt.
Thanks,
Karl