This will help free gears on the gear bearing from The Awesaversal Spool Gear, provided you use the default lip size. (http://www.thingiverse.com/thing:77163)

I had to free a lot of gears testing. It warranted a quick little design, also I don't like whacking on my sockets and they did the trick well.

Print with sufficient fill to hit with a rubber mallet. %80 2 shells worked for me.