It's just a big ring!
This is just the beginning of the column. We put it together to get an idea of how big to make things so that we could open it up and roller skate through it. I'm not really sure if it's too big or not. The outside diameter is 7 feet. It's really a challenge to make curved stuff and figure out how big it will be and also to get everything to meet at the end.
I hope we have enough K'nex to at least get this first section done, but seeing how big that is I think we're going to run out right away. There's definitely no way we can extend the column up to 24 feet and keep it that big, but I was never planning to anyway. I just hope I can get this one tall enough to skate under.