sammypants

Hi yall, I'm working on making a mobile crane and am trying to design a turntable using the 15 tooth banana gears (part no 78442) and 1x1 round tiles but I cannot for the life of me figure out how to constrain the upper gear. After all my searching, the best I've found is either this joint using the same idea of banana gears and 1x1 tiles, or this turntable that doesn't appear to do anything about the gap made by using the 1x1 tiles as bearings Both of those are also for the larger banana gears instead of the smaller ones and likely wouldn't work as well in a more space constrained space. Any ideas?

if I do want to get some of those, what part number are the wheels? edit: they're part number 50254

problem is, I don't have train wheels otherwise i probably would have tried that