Stonewall119

It's possible but a lot of work, and a lot of running around. I would guess and say you'd for sure experience some file degradation. The issue is that its a completely different file type. Again there are a few programs that will do it (especially if you're just looking for some basic function like poking a hole in it), but probably won't work the way you'd expect it to. even crossing solid files into other solid modelling programs is touchy let alone an STL. It would be easier to get the native file if you have them, or use the obj or stl as a base to remodel it in a new program like Alias, Solidworks, Mudbox, Zbrush etc. Most likely it will take a bit longer, but will be less of a headache and will produce better results.