Most fidget spinners are small discs that fizzle out after a couple of seconds. This project goes the other way entirely: a big handheld spinner with three large curved blades that keep their momentum once the wrist gets them going. The maker describes it as version 1 of a design they think opens up a whole family of spinning fantasy weapon builds, and a refined Demon Wind Shuriken variant is already in progress.
The layout is clever. A yellow ring frame with an inner handle carries an internal gear or bearing drive, and a flexible green clutch arm with ratchet teeth reaches in to catch the blades as they sweep past. The three teardrop-shaped blades use an open latticework pattern, two in bright green and one in yellow, and added weight in them helps sustain the spin. Assembly looks refreshingly simple: four M3 bolts, with the on-screen guidance correcting the length to 20 to 30mm, and nothing more than a printer and those bolts needed to finish it.
Some of the iteration here stands out. Thinner versions of the clutch spring had snapped, so the maker reinforced it. They also trialled a second ratchet on the opposite handle side, but gear play made the outer ring droop when pointing down and miss the teeth, while pointing up the arm barely touched the teeth yet still grabbed reliably. The single ratchet was judged good enough for version 1.
The interesting open thread is the redesign: the ratchet has been scrapped in favour of a locking lever to throw and stop the blades, and the first test pieces were just printing when this was shared. Whether that lever actually works as intended is still unknown, and the maker may fall back to a ratchet if it fails. Given that spinning this thing apparently turns into a full arm exercise after a while, the stakes are real.