This week’s selection is the Cat Door by Thingiverse contributor Cody Jeffries.
This not a complex 3D model, but it is a fascinating design. What is it? It’s a fully-functional cat door that one could install on a household door for cat access. Or, I suppose, any small critter that’s supposed to be in the home.
What’s most surprising about this item is that it is a single piece. I initially thought it might be composed of an outer ring with a flapping door, but no, it’s all connected together.
The second interesting part is the flap itself. This is not a solid door that hinges open and closed. Instead it is more like a curtain, where ten rows of solid pieces are each hinged to neighboring rows. The effect is a flowy curtain, albeit in only one axis.
Here’s a short animation of how it works with an actual cat:
To use this design you’ll have to 3D print the single piece. However, you should orient the print to be flat to ensure that the hinges 3D print correctly. It’s possible that some of the hinges may stick if the 3D printer is not calibrated correctly, but that could be rectified with a slight bit of force.
There’s also the matter of size. While Jeffries clearly sized the 3D print for his own cat, if you happen to have a larger animal you can consider resizing the design. Fortunately, it appears to be designed in such a way that resizing should be trivial to do, and should not compromise flap operation.
Installation is a bit more tricky, as you will have to cut a circular hole in your door to fit the door.
I quite like this design because it is functional, printable and involves moving parts. Boiling the mechanism down into a single piece should be the goal of most 3D print designs.
I don’t currently operate a cat, but perhaps you do.