Kugel Fountain - Floating Bowling Ball

This attractive hallway demonstration allows one to observe rotational motion with very little friction. A 3D printed base precisely matches the shape of the ball. Water pumped into the space between the ball and the base causes it to sit on a thin layer of water. It is free to spin in any direction with very little friction.

[@Jokervision744]

Gardener here. I did not know that we had one of those fountains, but suddenly someone came to question the basics of it, as they were sad, because the fountain was taken out.
Now I'm looking into it.

[@alec4672]

I've always been fascinated by these ever since I saw the one at Kennedy space center when I was a kid. They have like a 4ft one with a celestial map

[@ValpoPhysics]

Same here. It was so much fun to make one of my own.

[@GlutenEruption]

I have to go spin it every time I'm there. Love it

[@debbie4710]

Love the bowling ball, where did you get it?

[@thesingingfiremanphilipmiu5917]

Paul where did you get or make the two pieces the ball sits on? Please let me know

[@ValpoPhysics]

The 3d print file is linked in the description. It’s one piece.

[@banibon47]

You should make a business and sell these! I would totally buy one

[@c50ge]

Incorrect, you should build and sell these. The best salesman is the salesman who will buy what he sells.

[@Ra-bv6rm]

thx

[@banibon47]

What’s the feed water pressure?

[@ValpoPhysics]

I'm using a 300 GPH pump:
www.grainger.com/product/1P372
I don't know the pressure. This one says that it's capable of supplying water up 12 ft. So maybe a maximum of 7 PSI pressure. The flow is restricted by the ball, so I'm certain that it's running nowhere near 300 gallons per hour.