In the centre of the Clockwork Orange model will be a ratchet drive. The ratchet itself is mounted inside a tube which serves to locate the tiled strips in position. I’ve added a square tube loosely fitted into the main tube. This will hold the ratchet wheel into position so that the main axle can be located later on. A loose fit of the ratchet axle allows for some margin of error in assembly.

I’ve made four small snips in the bottom of the orange to allow the ratchet tube to fit into place.

The assembled unit slips into place in the orange lining up with the holes on either side.

The axle can then be slipped into place through the square tube and out the other side.

The drive ratchet strips will fit in like this. Note that the orange is upside down in this picture.

A double thickness key finishes off the clockwork look.

Next step – fitting the orange to the scotch yoke and connecting up the mechanism.