This is a little spinning toy I made for my nephew. It consists of three very different kinds of fish: Sawfish, Starfish and Shellfish. When it is turned upside down, the starfish doubles as a spinning top. Put it in the scallop and use the nose of the sawfish to spin the starfish in the shellfish. See the instructions and the video for more information.
How to spin the starfish:
Check out the the video for how it's done: http://youtu.be/OXPx3ca7Yj0
Tips & Tricks:
Playing with this thing will send hard plastic parts spinning through your room, so be careful! It will take a bit of practice until you get it spinning properly. Try holding the rack parallel to the gear and pull in a straight line. I also added a puller that should be a bit more effective. Use it instead of the sawfish if you want a bit more spinning action and less of the fish.
How this thing was made:
The body of the sawfish and the scallop were both created in Sculptris. It was the first time I tried this program so I'm quite happy with the results. The starfish, the sawfish-nose and the puller were made in OpenSCAD. I used Leemon Baird's public domain gear library for the gear and racks. The final composition was done in Blender.
The models printed well for me in the provided orientation, some support structures will be necessary. The gear is faced down and may need a bit more cleaning, depending on your support structures.