Fidget craze

[Uncle Fester]

Today I heard a kid crying in the pet shop, wanting a fidget spinner.
So it is not mice, budgies and guppies any more, like in my days.

What makes me feel really bad is why I did not try to market this toy myself years ago.
I was working with a group of entrepreneurs 15 years ago and did not see the obvious.

All my life I have been fidgeting usually with rotating objects, like ball bearings and propellers from model aircraft.
I always had to have something like that on my desk, at school, at work, although other things like ballpoint pens too usually fell victim
of my fidget disorder when they ended up as projectiles.
The issue here is that I was often not aware of my fidgeting until the front part of my pen (loaded with multiple springs)
accidentally ended up in front of the class room, which usually led to some form of punishment, although I was proud when it got so far as I
ALWAYS sat at the back of the room until I was punished by being forced to sit in the front(I would have rather had the cane).
Some also got stuck in the ceiling panels.
So I put it down to some kind of disorder and now it appears that every kid today has this disorder and wants something like this.
Well perhaps these toys will stop them at least from making projectiles.

My 10y/o wants of course a propper alloy one in brushed aluminium deep blue metallic with 4 steel ball bearings, not the plastic rubbish they sell in the local
stores... and now the Ebay order got LOST IN THE AUSTRALIAN POST Two weeks now from Victoria.

It had come to my mind to design a fidget cube that actually has real functions but I scrapped that because it would make you focus on the item rather
than what you are doing.

Anybody else care to share if they have this 'disorder'

[DB44]

My 13 year old nephew visited today. He had a plastic spinner, which I must admit is the first I have heard of this craze. His father was giving him a terrible time about it until I reminded him of some of the silly toys he had as a kid.

[VroomVroom]

yeah they seem trendy at present , ive even seen youtube vids on how to make one yourself

[lsemmens]

I found one on our kitchen bench a couple of days ago, and had no idea what it was, I thought it might have been some tool. At least my wife had an idea,she said it belonged to one of our grandchildren who had just left it there. What is the point?

[freakee1]

what's the point of yoyo's, collecting cards, beer cans, art, photos.........


cause you can

[irritant]

What is the point?

Helps for people like me with ADHD.

[David071]

Fidget spinners!

I work at two High Schools and we are all trieng to work out what to do with the craze and the kids which number dozens that have them in class and are disrupting classes!

Concensus of opinion is going to probably be - CONFISCATION of the item!!!

[trash]

and now the Ebay order got LOST IN THE AUSTRALIAN POST Two weeks now from Victoria.

Lodge an complaint with ebay now. I suspect a scam. Imagine if they hit 1000 people with a missing $5 item.
Nobody complains because they just think it got lost in the post. It's nice money for nothing.

I don't understand the fascination with some pointless spinning thing? Well not unless it's spinning at 30,000rpm.

[Uncle Fester]

Lodge an complaint with ebay now. I suspect a scam. Imagine if they hit 1000 people with a missing $5 item.
Nobody complains because they just think it got lost in the post. It's nice money for nothing.

I don't understand the fascination with some pointless spinning thing? Well not unless it's spinning at 30,000rpm.

Gyroscopes didn't fascinate you as a kid the way they seem to defy gravity?


The one we ordered finally arrived. It was not $5 but set me back $13 and these full metal types with the 4 propper ballbearings average ATM at $20-25 on Ebay from Aussie sellers.
My wife even saw them in London shops for £50.
You feel the gyroscopic precession when you twist your wrist and I find that relaxing.
This one will run for 3 and a half minutes with a single flick opposed to 30 seconds from the cheapest plastic ones.
While the target customers are kids, I never grew up, so of course I have spun it up to 30,000rpm with my air compressor.

[lsemmens]

I have spun it up to 30,000rpm with my air compressor

How do you know? Did you count as it was spinning?

[Uncle Fester]

How do you know? Did you count as it was spinning?

Awww... come on thats easy.
The spinner has three arms so if I hold the compressor nozzle so it blows against the top to make it to spin it makes a distinctive sound with a frequency that an app on my ipad called signalscope measures. It was actually only about 1.2kHz divided by 3arms = 400 rps or 24,000 rpm but that was still quite impressive.

[irritant]

I have a big ball of press-stick putty that I squeeze, stretch out long and thin, then roll it up into a ball again, and start again.

[irritant]

...1.2kHz divided by 3 arms = 400 rps or 24,000 rpm...

Why does one have to divide by 3 in this case? Do the 3 arms increase the frequency of the sound 3-fold?

[Uncle Fester]

Why does one have to divide by 3 in this case? Do the 3 arms increase the frequency of the sound 3-fold?

The three arms produce the sound as they interfere with the flow of the air from the nozzle. So this happens three times per revolution.

[Uncle Fester]

I have a big ball of press-stick putty that I squeeze, stretch out long and thin, then roll it up into a ball again, and start again.

Have you tried the cube?
I use it when I have to sit or stand around with people and talk in areas where I can not be productive like building something or using the input devices of a computer.
It stops me from pulling bits of skin off my fingers and destroying pens.

[irritant]

The three arms produce the sound as they interfere with the flow of the air from the nozzle. So this happens three times per revolution.

Ah OK. But, wouldn't different shapes of the arms, etc. have an effect on the frequency tone? Like another one with 3 arms but different shape arms making a different sound?

Maybe another way to "check/confirm" it, is to use the relationships in physics. So, if you can somehow determine the force in N with which the air is hitting one of the arms and get from there to angular velocity, then you can get the rpm.

Or somehow determine the torque - use radius, get to force, then angular velocity, divide by 2*pi*r, then get rpm.

[irritant]

Have you tried the cube?

The one with the switches and buttons and stuff? No, not yet.

[Uncle Fester]

Ah OK. But, wouldn't different shapes of the arms, etc. have an effect on the frequency tone? Like another one with 3 arms but different shape arms making a different sound?

The sound might change but not the base frequency.
The scope app can be switched to FFT so you can see the harmonics that create the sound.
The so called fundamental is the lowest frequency in the spectrum. It also has the highest amplitute and that represents the revolutions per second similar to the vibrations of a string on a guitar.
The musical reference tone A4 will sound totally different played on a guitar, violin, flute or piano but their fundamental will always be 440Hz, while the harmonics that make the instrument sound rich and good will be all over the place, especially when the three strings per piano key intermodulate because they ae rarely 100% in tune.

[Uncle Fester]

Maybe another way to "check/confirm" it, is to use the relationships in physics. So, if you can somehow determine the force in N with which the air is hitting one of the arms and get from there to angular velocity, then you can get the rpm.

Or somehow determine the torque - use radius, get to force, then angular velocity, divide by 2*pi*r, then get rpm.

Way too many variables here and how would you measure the force.?
The force is dynamic and goes towards zero when the velocity of the air from the nozzle reaches towards the rotational speed at the circumference of the spinner.
Very hard to grasp here is the friction of the device at that speed, both from the bearing and the area not exposed to the flow from the air nozzle.
A very rough estimate would be the velocity of the air coming out of the nozzle which could be derived from the pressure inside the nozzle and the surface area of it's opening.
Trash might have a method to determine the speed simply based on the physical properties but he thinks these spinners are boring.
Then again anybody who designs a steam turbine would have to calculate that.

...but as long as I have all the gadgets, my method is easy and is quite accurate.
You could of course also use a simle photo diode circuit connected to a multimeter with a frequency range.

[trash]

Gyroscopes didn't fascinate you as a kid the way they seem to defy gravity?

No, not really. Unfortunately Newton's laws of motion take the mystery out of it.
My son however likes the magic. I saw some spinners for $3 each in a shop a couple of months ago.
I couldn't work out wtf they were or what they were for. It was only that some woman said to me, kids are going nuts for them and they all want one.
So I bought a couple once each or the kids an one for me, just in case I needed to experiment on one.
I spun it up with a rubber wheel on an electric motor to about 2000 rpm.

The only thought in my head was.... how do I weaponise this?

Awww... come on thats easy.

Beat me to it. The audio sound is good for high revs. In my case.. just holding up to the AC light is enough.
I also have a nice strobe which could be used if I wanted some kind of precision.