Since posting my smooth motion modification to the Dragon Dance set, I’ve been doing some more experimenting with the mechanism for it. Instead of continuing to modify that set, I thought it would be more interesting to build my own dragon, and for inspiration I turned to Falkor, the luck dragon from The Neverending Story.
The updated mechanism features an even smoother wave motion with an increased amplitude. I was able to achieve a cam offset of 30 degrees between adjacent cams (instead of the 45 degrees used in the Dragon Dance modification), and increase the travel height of each segment from 1 stud to 2 studs.
In addition, I was able to make each segment of the dragon tilt as it traveled, to stay at a tangent to the wave that is traveling through the body. You can see the model in action in the video, along with an explanation of the mechanics.
The stand is decorated with some imagery from the story, including the Ivory Tower and the Southern Oracle. The black pieces on the right side of the stand represent the Nothing, which is slowly taking over the world.
You can find building instructions below, along with some notes to help make it operate smoothly.
As with any Technic model, it is important to ensure the mechanics operate smoothly while being assembled. Once the cam shaft is assembled and inserted into the base, ensure it can rotate freely, without catching on any parts of the base. You may have to slightly adjust the positions of some of the liftarms or pulley wheels.
Similarly, once the body supports are attached to the top of the base, ensure they can travel up and down freely. If any seem particularly tight, you can wiggle them a bit, to slightly adjust the bricks in the frame and increase the available space. You may notice they will catch on the top of the frame if you lift them up too much, but they never travel that high during normal operation.
Over time, you may find that some of the supports will start to intermittently stick. I have found that adjusting them again usually fixes this. Dust accumulation can also cause problems, so keeping the model clean will help. Applying a PTFE based lubrication on the moving parts can also help keep the model running smoothly.