22MIL2DAY,
Typically I print with a layer thickness of 0.2 mm, a lot of people use 0.15 or 0.1 mm. MakerGear has done some experimental prints down to 0.02 mm layer thickness (20 microns) with some amazing detail.
Search the MakerGear forum for answers like this. Lots of this sort of stuff has been covered there. Go to
http://www.makergear.com/ and in the "Instructions" pull-down menu, select "MakerGear Google Group".
Dale