I took Brady's suggestion and bought the stubby collet chucks. They worked so well I ordered more of them. The stubby goes into a 1/2" collet and allows you to put in almost any size sub chuck for drills or whatever.
If you look at the wooden orrery post, that was all done with a 1/8" downspiral in the stubby. I have 1/4" collets for the stubby also so I can extend the reach of my 1/4" bits down into deep valleys. That has sometimes been just exactly what I have needed.
I highly second Brady's recommendation.
"The best thing about building something new is either you succeed or learn something. Its a win-win situation."
--Greg Westbrook