Jack-O’-Spin Tippie Top – The Physics Behind a Flipping Pumpkin

This is my Halloween take on the Tippie Top, a fascinating physics toy that spins upright after being launched on its side. At first glance, it looks like magic — but it’s pure dynamics.

The inversion happens because of a shift in the center of mass relative to the symmetry axis. When the top spins, frictional torque between the surface and the contact point produces a precession that gradually reorients the top’s angular momentum.

As energy dissipates, the center of mass rises, and the top flips — continuing to spin stably upside down. I modeled mine as a Jack-O’-Lantern version: printed in two parts (body + textured handle for grip) so it’s both fun and a practical classroom demo of rotational dynamics, friction, and stability transitions.

🔗 Download the STL or the 3MF for free: https://makerworld.com/es/models/1886309-jack-o-spin-invertible-halloween-spiner-tippe-top#profileId-2020297 If you’ve ever wanted to see conservation of angular momentum and frictional torque at work, this little pumpkin shows it perfectly. 🎃⚙️