Hi and thanks for visiting,
This model made in Rhino 7 using the new SubD functions. I made a legacy save (Rhino 5) but could not test how it reads the SubD object.The native file contains the reference image, construction curves and the base NURBS object I used to achieve the final result.The other formarts exported from rhino and contains only the final model. ( Still scaleable )
UPDATE:
For request the package have a model without the hook ( circle part on the top for the chain)see Violin key No hook.obj and Violin key No hook.stlRhino file contains the base mesh without the extra part also.
Have a nice day