Watch a fidget spinner spin at 50,000 RPMs... and then break


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I wonder how fast those pieces were going. I hope he was wearing a cup.


“Fidget spinners - idle distraction? Or deadly shrapnel? We’ll show you how your child could be in serious danger from these innocent-looking toys, right after the weather with Bob Burpmore. Bob?”


My friend bought a spinner in NYC a couple weeks ago, and one of my coworkers has one. One thing I can’t quite figure out is what the point of these things is?



“Safety squints engaged.”


Spinners, or friends and coworkers?


Spinning a ball bearing with compressed air = deadly.

Quite a few people were either injured or killed that way.
If it the bearing comes apart… you can take a ball bearing through the heart… or head.

Somebody should point that out !!!


Everyone’s favorite Finnish suicidal maniac puts the failure speed at around 20.000 RPM:


I was just hoping he had eye protection, but sure, that too.


That was my first thought, but I went with the crude joke, alas.

I still want to know how they figured the RPM. Strobe light, maybe?


To me it looked more like 50 bajillion RPM.


Vice (n): moral depravity or corruption, also a pretty good culture print/e-zine, formerly out of Montreal.
Vise (n): any of various tools with two jaws for holding work that close usually by a screw, lever, or cam

(with thanks to Merriam-Webster)


I’m trying to figure out whether you could do it algebraically. Presumably you know exactly what the pressure output is at the compressor nozzle. You could figure out the air resistance, but you would have to empirically measure the coefficient of friction of the central bearing.

The fact that I’m thinking about it this much is a clear sign that I should step away from the keyboard and go be more productive. Like make dinner.


I guess that’s about as accurate.


I was thinking you could figure it out from the geometry and ultimate tensile strength of the plastic fidget, and radius of the break – but that assumes no surface flaws. I’m definitely overthinking this just to demonstrate macho engineering prowess.


Materials or mech eng?


Biomaterials with a little biomechanics. More the intersection than the union. :rolling_eyes:


Great. Someone is gonna show this to 45 and we are going to have a political “war on fidget spinners”.


Couldn’t you determine rpm from the mass & speed at which part of the spinner struck the wall or something? And the speed could maybe be calculated from the depth the piece was embedded in said wall? Maybe you’d also need the relative density and …

Or just say “over 50000” and hope nobody questions it… :slight_smile: