Hypocycloid

My children were excited to see the illusion where an object could make lines move in straight lines but when added with the other points could appear that there is rotation happening.  Reference the link below for a great explanation and visual concept.

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=video&cd=&cad=rja&uact=8&ved=2ahUKEwiU86Do8KL-AhV-m2oFHYv5BgUQtwJ6BAgGEAI&url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3D0Vs_dq323_I&usg=AOvVaw20ssv9-VHpzbXuGk3wGSzd

Here's another video showing all of the different patterns that can be achieved

https://www.youtube.com/watch?v=gTsdoR2rqwk

I had to redesign the crank as I was not able to get the threads correct, I used M3 hardware to secure the handles together.  If printing CrankStyle2, you will not need any supports.  The top lid is intended to be loose to allow for play, I may make this tighter in the future.

Used organic supports on Crank 1 and was easily removed, when importing the cycloid, this will appear fully assembled but ensure when prompted about Multi-part object, select “No” so it will separate each component