In Christmas break I made a K'nex/Lego Drop tower, which is nearly 6ft tall! The tower is made out of K'nex and the track, vehicle and the drop releaser are made out of Lego. I use Rubber bands to break the vehicle down. To release the drop I use a remote, but I have to pull the vehicle up by hand.
The facts:
Height: 5.7ft (174cm)
Track height: 4.6ft (140cm)
Top width: 1.6ft (48cm)
Tower width: 0.5ft (16cm)
Base: 1.5ft x 1.5ft (46x46cm)
YouTube Video is comming soon. But I have a short preview Video for you.
Here are some pics and if you have questions, then you can ask me and I'll answer them.
The base
My cat is the construction chief
The topping off
Finished