Rattleback

The Magic Rattleback (Physics-Defying Top) "More stubborn than your best friend: It strictly refuses to spin the way you want!" "Spin it wrong, watch it fight back, and question your existence!"Why This Top Is Broken (In a Good Way)Self-Reversing Mechanism: Spin it counter-clockwise, and it will literally shake, stop, and reverse direction all by itself!Pure Physics: No batteries, no magnets, and no electronic tricks. Just geometry and friction at work.Ultimate Desk Companion: More stubborn than your daily deadlines! Perfect fidget toy to confuse your coworkers and showcase your 3D printing skills.Print Settings for Maximum Reversal PerformanceInfill / Shells: Set to 100% Infill or 8+ Wall Loops. It requires adequate mass to build up proper momentum!Bottom Surface: Lightly sand the curved bottom with fine sandpaper (1000+ grit) so it rocks and spins smoothly without layer friction. "Reverses harder than your ex: Even Newton's laws would be confused!"Drop a like if it breaks your brain, and share your spin videos in the comments below!