Ok, I now understand what Simplify3D is and isn't. That's helpful.

It's a bit tough getting used to the 3D controls in FreeCAD, but I *WAS* able to do it. Thanks!

My main problem with the various programs I have (Autodesk Meshmixer, Blender, DesignSpark Mechanical, FreeCAD, SolidWorks) was that I was having a real difficulty figuring out how to create a simple box to mesh with the existing gear. Once I figured it out, then the problem was modifying the box to be the unusual shape I wanted. I have the two melded together, but in DesignSpark & FreeCAD, you can see that they're two different "materials," and I can't figure out how to change that. Also, the bars have LOTS of polygons on them (visible in DS), which make them difficult (if not impossible) to manipulate in that program. That's why I went back to Maya - that was a program I knew how to use, at least.

So, I've downloaded Fusion360, and I'm going to start taking a look at that. The Motion Study Analysis feature is one I will DEFINITELY need.