Turning giant turntables

[EricH]

Try a Colson wheel on a smooth turret base. The Colson gets mounted to a motor/gearbox that gets you the speed you need.

Reference: Behind the Design, 2006: FRC121's turret power source.

[Akash Rastogi]

One of the options I like is using whatever round thing you want in the diameter turret you want and mounting an inside out timing belt to it so the teeth point out. Use a small diameter belt on another sprocket or whatever on the output shaft of your gearbox. Mesh them together and boom! Super easy, Eric's method works as well.

[Electronica1]

So, are you looking for something this big, or smaller?