K'nex Giant Ferris Wheel

This is my first Instructable. It's for a 234 cm(7,68 ft, 92,1 in) tall K'nex Ferris Wheel.

I often had problems with K'nex ferris wheels, because it's hard to keep the towers strong, when they are only connected with one black rod.

This ferris wheel has an open hub, so there is room to connect both towers by a strong bridge.

First you have to build the base which holds both support towers, the 12V engine, and the first reduction gears. It also forms the boarding platform. It looks really small for the size of the wheel, but it did a good job on mine. When you take it outside, it might be an idea to add further support. For indoors, this is good enough.

Next is support tower 1 It's a fairly simple red rod tower. It also has the drive shaft attached to it, which drives the wheel.

Support tower 2 is built up of yellow rods. On the bottom end there is a red rod block, which is attached to the base. It's important to make the connection between the red block and the yellow tower quite strong, if you don't, the tower might break there.

It's important to put a gray connector on one of the vertical rods on the top block. This will be connected to the bridge between the towers.

The top of tower 1 has the final drive on it, which makes the connection between the vertical drive shaft and the chain drive.
The bridge which runs through the hub, from tower 2 is also attached to this part.
It also supports one side of the drive/support shafts.

The top of tower 2 is quite simple, it doesn't have any gears in it. It supports the drive/support shafts, and it has the bridge on it.

These shafts hold the weight of the wheel itself, and also drive the wheel via 2 chain drives. It's important to fill the rods completely with rings, wheels and connectors. If not, there may be too much room at the bearings, so the shafts may fall out.

For the main shaft (right one, from top to bottom) the following parts go on the rod.

1 grey connector
1 ring
1 big wheel, with rubber bands around it, these add grip.
2 beige wheel holders
1 red wheel
2 beige wheel holders
1 red wheel
14 rings
1 beige wheel holder
1 big wheel
2 beige wheel holders
2 red wheels
1 beige wheel holder

The second shaft is the same, exept that it hasn't got the second set of red wheels. Fill up this space with rings and beige wheel holders.

Quite simple really, build all the parts together, to form the towers, whith the drive mechanism.

The wheel is built up out of 31 elements. The elements themselves have 3 parts, the drum part, the wheel part, and the car part.

Building the outer ring is a matter of fine tuning. I found the easiest way to do this was to attach the wheel to the tower, and testing a bit with blue and white rods.

The cars I've built are very simple, but it was all the K'nex I still had left, you can build whatever car you like.

By building the wheel in two halves, they can be mounted around the bridge/drive/support shafts. Each halve will be HUGE by now. I've tied a rope around my ceiling lamp to keep the top halve up, while connecting the bottom halve. Another possibility is to keep the top halve balanced on top of the two drive/support shafts.

I found it easy to keep the car parts(everything outside the outer ring) of until the wheel was mounted on the tower.