Wow, well over 3,000 views and going on 90 replies. This thread is a hit! :)
Guys, I may have a new spin (no pun intended) on how to set you gears on a shaft and with a little TLC, have the least resistance possible and no slop going on. This here little gizmo should be familiar to most router heads. It's a "roller bearing":
http://i50.photobucket.com/albums/f3...lerBearing.jpg
This particular little puppy came off of a 1/2" shank router bit, so naturally the inner hole is exactly 1/2" diameter, which should fit very snugly over 1/2" dowel rod with maybe a little persuasion. The outer diameter is 1 1/4", easy enough to cut your center hole to fit with maybe a little glue. The bearing is about 1/4" thick.
The inner and outer rings spin independently of one another on sealed greased bearings. Smooth as silk. Similar to shoulder bolts, this set-up would allow you to securely fasten your rod (axle) to your base (you DON'T want your rods to spin!), while allowing your gears to spin freely and securely.
Make sense? hmmm.... http://www.ebay.com/itm/UNIDENTIFIED...item5d2e7bc1c8
p.s. Never mind those harmonicas in the background of the pic. I can't play. :(