I needed some smooth round parts recently for some models I was building and chose to take an unconventional approach by building a mini lathe on which to turn them.
The parts were designed in Draftsight and cut from 3mm ply on Nottingham Hackspace's laser cutter. The lathe is built from two finger jointed boxes on a base plate. One of the two boxes has plates screwed inside and outside of the faces to hold a pair of bearings that support a free spinning motor shaft. The second box has an old GWS brushless motor mounted inside. The friction fit seems sturdy enough but two rails of beech engine bearer stock are screwed to the sides for extra rigidity and the base is clamped to a worktop to reduce vibration.
A suitable electronic speed controller and lithium polymer battery provide power to the motor. Control signals for the ESC are provided by a cheap servo tester.
The work piece is drilled out slightly smaller than the two shafts and threaded on. The friction fit acts as a clutch helping to prevent damage to the motor or drawing excess current and puffing the battery if it stalls.
For tooling I used various forms of sandpaper and a craft knife. Anything that will cut or erode the workpiece without stalling the motor should work okay. I've found it takes a delicate touch but it is easy to shape the workpiece with some practice.
There are a few downsides to the simple construction: the rails need to be unscrewed and the boxes removed to insert or remove the work piece, and the lathe is only suitable for turning very soft wood such as balsa dowel. Regardless of this the very low cost and simple task required of it it did an excellent job, though I won't take responsibility for any fingers lost attempting to replicate it.