[daltore]

ausTIN CANs just used cheap little 5" Lazy Susans (something in the range of $5, I think). Due to the low friction this year, we only used one on each module, and we did end up with a little bit of jamming, but for our summer project we're planning to do something very similar, but with 2 Lazy Susans, one on top and one on bottom. Lazy Susans are very nice because they can support a surprising amount of load, and have large plates with mounting holes on them. They require a bit of setup maintenance (bending the plates a bit to align the bearings better and crimping the inner flange that holds the two halves together tighter so it doesn't wobble), but if you have the side loads distributed between two of them, you shouldn't have to align them ever again. And for that price, if you screw one up, it's not a big deal, you don't have to machine another one.