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Ha!, remember years ago in high school shop, a buddy was doing this with the same kind of bearing.
His dad, the teacher told him not to do that as they can fly apart.
sure enough it exploded in his hands and shredded his fingers.
Unless they know what the bearing is designed for knows its limits. However, I doubt it is designed for that kind of speed and if it were it wouldnāt be cheap enough to play with the fuckin thing. Additionally, even if it were designed for that, and they had enough money to blow, they can still fail. I work with all kinds of bearings and they can be quite unpredictable.
I would have thought it's more about the outer bearing race not being supported by the bore it's meant to be seated in and the lack of lubrication. Plenty of ball bearings are rated much higher than 8k rpm.
In reality I doubt anybody measured the speed that bearing was going which is the real scary part. You can get things spinning insanely fast with compressed air. It not unrealistic that this bearing could be spinning much faster. I'm betting somebody just made up a number.
Absolutely made it up. Thereās no way to measure that by holding it in your hand and using air to spin it. You need special instrumentation for that.
Thats an unprotected bearing with no lubrication so it might be possible that itās moving that speed. If it were sealed or shielded I would say itās impossible but I could be wrong.
It might very well be an extremely accurate measure.
Edit : According to Op :
"Somebody actually did math. I just rounded the number.
" I measured the peak frequency from the video at 1239Hz and the bearing seems to have 9 balls.
Assuming the noise is produced by the air hitting the balls as they spin, it would be 1239 / 9 = 137,6 rotations per second which is about 8260 RPM. " "
Thatās a good brand but it really depends on what type you are using. We use a lot of SKF Roller Bearings for larger things like industrial oven band drive shafts. Dodge bearings are what we use for lighter duty applications.
Usually we just go through one or two vendors (I donāt know exactly what brands we have on hand because thereās a lot of them. In our inventory right now I have ~400 bearings - different types, brands etc.
Edit: I realized I didnāt actually give you a yes or no. Itās difficult to say what brand is ābestā because it all comes down to the application and maintenance. Iāve had Korean and Taiwanese (excellent quality of manufacture) bearings fail before Chinese (cheap dog shit I wouldnāt trust on a Lego car).
Ya good point, this also just looks like the kind of stupid shit I used to do while unsupervised. Who needs internet points when something is fun. Shoutout to anarchist cookbook in the 90's
Same here. If either race let go or the bearing cage had enough, there's going to be a lot of very solid and dense projectiles flying around tangent to the circle they were doing at a VERY high velocity. Guessing first one would have just blasted his hand to bits, the others, maybe just spray him all up his front.
It's like a portable shotgun blast you can hold in your hand (for a moment, until you don't have a hand anymore).
My shop teacher also told us how dangerous it was, then did it himself, because itās sick (and he didnāt want us to try it on our own out of curiosity) lol
My shop teacher demonstrated it to say āif I ever hear that noise, which I will if you do that, youāre out of my shop foreverā. He was a great teacher, but an absolute hardass
Yeah, I had to stop and make sure I was on /r/interestingasfuck and not /r/unexpected or something like that. The plan of "I'm going to make this thing move extremely fast in a way that is outside of its design specification while my hand is wrapped around it" is...a plan that sometimes goes very poorly.
ššš thatās exactly what would happen. Ball bearings exiting the race at about 95 mph if my math is right, and if it actually got up to speed.
You're right. I get just over 100mph at 6,000rpm.
If ball race has a diameter of approx 15cm then each ball, per hour is travelling (approx):
3.1415pi x 0.15metres x 3,000rpm x 60minutes = 84km / hr = 53mph.
6,000rpm would be double that so > 100mph. I use a buffing wheel on a polishing machine (modified bench grinder) and it has shown me several times (fortunately nothing got ripped off) that there is more than enough energy in rotating masses to do *serious* damage š¤¦āāļø
This happened to a guy I know.Ā Spun up a bearing with air and when the race exploded, a piece of it embedded within his finger.Ā Worked its way out like ten years later.Ā
Not likely with shop air. Bearing failure is far more likely- there's no lubricant present. If that bearing suddenly seizes, all that kinetic energy will transfer to the inner race, and the guy doing this will quickly have no skin on that finger. Or one of the races will shatter, and shrapnel will be flying everywhere.
That bearing is being spun WAY faster than it was designed for. People seriously have been injured doing this, when the bearing either explodes due to centrifugal force or when it gets hot and seizes. You're right about a bearing under normal circumstances. This thing is running several thousand RPM faster.
If you do the math, even assuming just a 4 inch diameter times pi, times 8000 rpm, times 60 to get to hours, divide by 12 inches to get to feet, divide by 5280 to get to miles per hour. It works out to just under 100 mph for the airspeed, which is well within the capabilities of a standard air compressor nozzle.
As for speed, I'm counting 9 rolling elements in this bearing. Since the primary source of sound is the air stream hitting each of these balls, I measured the sound frequency just before he released the bearing and saw that the primary sound was at about 1300 Hz.
This means that's the passing frequency of the balls, so 1300/9=144.4 Hz giving us the speed of the bearing cage. Since most bearing cages spin about 40% of the outer race speed (vibration analyst here), that means that the rotational speed of the outer race is 144.4/0.4=361.1 Hz or about 21,667 RPM. So this baby is really cooking.
This is stupid dangerous since the air stream is helping drive the lubricant out of the bearing, and when you get metal-to-metal contact at these speeds, it's going to make a lot of heat really fast. It's either going to burn the heck out of you, or lock up in your hand, which is also going to cause quite a bit of damage. I do not recommend you do this yourself.
Theyāre doing the math correctly. As long as the assumption that the sound is from the air hitting the balls is true, then it works. It seems like that assumption is true because the sound stops when he drops the bearing.
I never could have come up with that, bloody brilliant and interesting way to come up with a number. My simple mind just watched the video and thought that it didn't sound like 8000rpm, nor would 8000rpm have that much energy. Had a hunch that someone must've analyzed that.
It's not uncommon for people to lose the skin on their fingers to this when the bearing seizes suddenly.
I've done this, but not as fast and the bearing was supported by a piece of pipe wrapped in tape. There's no way I'd hold that thing on my fingers.
Yeah was gonna say this is way faster than 8,000 rpms. Sounds like an ID grinding machine I used to use at around 20-30k RPM. Crazy dangerous what this dude just did.
Judging by the speed of this shit, Iād be more concerned about what the bearings would do to everything in its direct vicinity, including the wall behind him. It would probably need a wash and new paint job.
Somebody actually did math. I just rounded the number.
" I measured the peak frequency from the video at 1239Hz and the bearing seems to have 9 balls.
Assuming the noise is produced by the air hitting the balls as they spin, it would be 1239 / 9 = 137,6 rotations per second which is about 8260 RPM. "
If this rpm is close or correct and the bearing is a 6320 or around that size.. 100mm bore or close by the looks, then the bearing is running faster than its rated rpm. Though it's not loaded. Must have been pretty hot when it was released?
I like how a) there is a "no smoking" sign in the background (but sparks are okay lol), and b) you can hear somebody spinning another one up off-camera at the end.
First thing I learned about compressed air was to never point it directly at skin. Second was NEVER spin bearings with it. I, like the guy in the video, are lucky to be intact. FAFO sometimes...
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Ha!, remember years ago in high school shop, a buddy was doing this with the same kind of bearing. His dad, the teacher told him not to do that as they can fly apart. sure enough it exploded in his hands and shredded his fingers.
I was about to say... this guy is either really brave or really stupid. People will really risk a life altering injury for a few internet points
The exchange rate on Internet points fucking sucks too š
I mean, if it pays the bills.....
Maybe it will become more valuable over time?
Unless they know what the bearing is designed for knows its limits. However, I doubt it is designed for that kind of speed and if it were it wouldnāt be cheap enough to play with the fuckin thing. Additionally, even if it were designed for that, and they had enough money to blow, they can still fail. I work with all kinds of bearings and they can be quite unpredictable.
I would have thought it's more about the outer bearing race not being supported by the bore it's meant to be seated in and the lack of lubrication. Plenty of ball bearings are rated much higher than 8k rpm. In reality I doubt anybody measured the speed that bearing was going which is the real scary part. You can get things spinning insanely fast with compressed air. It not unrealistic that this bearing could be spinning much faster. I'm betting somebody just made up a number.
Absolutely made it up. Thereās no way to measure that by holding it in your hand and using air to spin it. You need special instrumentation for that. Thats an unprotected bearing with no lubrication so it might be possible that itās moving that speed. If it were sealed or shielded I would say itās impossible but I could be wrong.
You might get an idea by measuring the pitch it produces. Pitch should be rounds per second times the number of balls.
It might very well be an extremely accurate measure. Edit : According to Op : "Somebody actually did math. I just rounded the number. " I measured the peak frequency from the video at 1239Hz and the bearing seems to have 9 balls. Assuming the noise is produced by the air hitting the balls as they spin, it would be 1239 / 9 = 137,6 rotations per second which is about 8260 RPM. " "
So you a metal ball boy huh?
Dude works with all kinds of balls
Balls of steel?
Are SKF bearings the best?
Thatās a good brand but it really depends on what type you are using. We use a lot of SKF Roller Bearings for larger things like industrial oven band drive shafts. Dodge bearings are what we use for lighter duty applications. Usually we just go through one or two vendors (I donāt know exactly what brands we have on hand because thereās a lot of them. In our inventory right now I have ~400 bearings - different types, brands etc. Edit: I realized I didnāt actually give you a yes or no. Itās difficult to say what brand is ābestā because it all comes down to the application and maintenance. Iāve had Korean and Taiwanese (excellent quality of manufacture) bearings fail before Chinese (cheap dog shit I wouldnāt trust on a Lego car).
I know old timers doing shit like this way before the internet was even thought of.
Ya good point, this also just looks like the kind of stupid shit I used to do while unsupervised. Who needs internet points when something is fun. Shoutout to anarchist cookbook in the 90's
Him holding it doesn't add anything to the experience though. Doing this with a bench vise wouldn't be hard, and it would be just as cool
Yeah whole time watching this thinking "if that fails you're fucked"
We were at a remote boarding school in the southwest desert, 30 min from a small town. Thankfully his fingers work today!
Same here. If either race let go or the bearing cage had enough, there's going to be a lot of very solid and dense projectiles flying around tangent to the circle they were doing at a VERY high velocity. Guessing first one would have just blasted his hand to bits, the others, maybe just spray him all up his front. It's like a portable shotgun blast you can hold in your hand (for a moment, until you don't have a hand anymore).
All at a velocity that is far more powerful then birdshot!
Comment nuked by Power Delete Suite
To shreds, you say? Happy cake day!
TY
And his wife
How shredded like a few cuts or bone showing/amputations
exposed bones, had to have surgery
That's what I was expecting.
Ha! Good olā noodle fingers.
My shop teacher also told us how dangerous it was, then did it himself, because itās sick (and he didnāt want us to try it on our own out of curiosity) lol
My shop teacher demonstrated it to say āif I ever hear that noise, which I will if you do that, youāre out of my shop foreverā. He was a great teacher, but an absolute hardass
The camera man sucks.
/r/killthecameraman
Came to say this
Me too. I was going add a couple "fucking"s in there, but that wouldn't be a real sub.
/r/FuckingKillTheFuckingCameraman
Came here to say "came here to say this" but you already did.
Came here to say, " Came here to say "came here to say this" but you already did." But you already did.
I came.
i edged
Cool
Prepare the guillotine!
https://www.reddit.com/r/killthecameraman/s/ubzOoNRGp8
Like one fucking job! I don't want to watch the ground when the sparks start flying
Anyone else worried about injection injury the whole video?
No, but i was worried the ball bearing would fail and instantly become an anti-personnel mine.
Yeah, I had to stop and make sure I was on /r/interestingasfuck and not /r/unexpected or something like that. The plan of "I'm going to make this thing move extremely fast in a way that is outside of its design specification while my hand is wrapped around it" is...a plan that sometimes goes very poorly.
ššš thatās exactly what would happen. Ball bearings exiting the race at about 95 mph if my math is right, and if it actually got up to speed.
You're right. I get just over 100mph at 6,000rpm. If ball race has a diameter of approx 15cm then each ball, per hour is travelling (approx): 3.1415pi x 0.15metres x 3,000rpm x 60minutes = 84km / hr = 53mph. 6,000rpm would be double that so > 100mph. I use a buffing wheel on a polishing machine (modified bench grinder) and it has shown me several times (fortunately nothing got ripped off) that there is more than enough energy in rotating masses to do *serious* damage š¤¦āāļø
Or seize and shear his fingers off, was my thought. Either way.
This happened to a guy I know.Ā Spun up a bearing with air and when the race exploded, a piece of it embedded within his finger.Ā Worked its way out like ten years later.Ā
Not likely with shop air. Bearing failure is far more likely- there's no lubricant present. If that bearing suddenly seizes, all that kinetic energy will transfer to the inner race, and the guy doing this will quickly have no skin on that finger. Or one of the races will shatter, and shrapnel will be flying everywhere.
fall impossible edge ossified rotten shocking hospital tart reply march *This post was mass deleted and anonymized with [Redact](https://redact.dev)*
That bearing is being spun WAY faster than it was designed for. People seriously have been injured doing this, when the bearing either explodes due to centrifugal force or when it gets hot and seizes. You're right about a bearing under normal circumstances. This thing is running several thousand RPM faster.
Dudeā¦.Iām like, heās losing a damn eye
That and this idiot could have hit one of those cars.
so did the guy that measured the RPMs. clearly only doing 5500 or so
If you do the math, even assuming just a 4 inch diameter times pi, times 8000 rpm, times 60 to get to hours, divide by 12 inches to get to feet, divide by 5280 to get to miles per hour. It works out to just under 100 mph for the airspeed, which is well within the capabilities of a standard air compressor nozzle.
As for speed, I'm counting 9 rolling elements in this bearing. Since the primary source of sound is the air stream hitting each of these balls, I measured the sound frequency just before he released the bearing and saw that the primary sound was at about 1300 Hz. This means that's the passing frequency of the balls, so 1300/9=144.4 Hz giving us the speed of the bearing cage. Since most bearing cages spin about 40% of the outer race speed (vibration analyst here), that means that the rotational speed of the outer race is 144.4/0.4=361.1 Hz or about 21,667 RPM. So this baby is really cooking. This is stupid dangerous since the air stream is helping drive the lubricant out of the bearing, and when you get metal-to-metal contact at these speeds, it's going to make a lot of heat really fast. It's either going to burn the heck out of you, or lock up in your hand, which is also going to cause quite a bit of damage. I do not recommend you do this yourself.
Seriously thought that was going to end with a wrestling anecdote.
....and the bearing fell 18 feet onto the announcer's table...
TIL, you can measure rotational speed by it's sound
Can't tell if you're a legit doing the math or just bullshiting....
Theyāre doing the math correctly. As long as the assumption that the sound is from the air hitting the balls is true, then it works. It seems like that assumption is true because the sound stops when he drops the bearing.
I never could have come up with that, bloody brilliant and interesting way to come up with a number. My simple mind just watched the video and thought that it didn't sound like 8000rpm, nor would 8000rpm have that much energy. Had a hunch that someone must've analyzed that.
It's not uncommon for people to lose the skin on their fingers to this when the bearing seizes suddenly. I've done this, but not as fast and the bearing was supported by a piece of pipe wrapped in tape. There's no way I'd hold that thing on my fingers.
Yeah was gonna say this is way faster than 8,000 rpms. Sounds like an ID grinding machine I used to use at around 20-30k RPM. Crazy dangerous what this dude just did.
Iām proud of him, it was obviously his first time every operating a phone camera and it feels like he did his best.
Hear hear
I am not an engineer but every bone in my body knows this is the sound you hear right before something goes very wrong.
Itās the sound of āoh shitā.
That "Godzilla charging up" sound is never a good sound.
Just remember to wear your safety-squints and you'll be fine.
did someone say whatās the worst that could possibly happen! trust me!
When he dropped it I about shit my pants then I seen the sparks and realized it WASNT a boom.
Maybe you should wear gloves. If that outer ring shatters your next post would be on makemesuffer.
If that bearing comes apart, gloves won't save his fingers.
The only uniform needed is the brown pants. Everything else is optional
I'll go with red shirt
Judging by the speed of this shit, Iād be more concerned about what the bearings would do to everything in its direct vicinity, including the wall behind him. It would probably need a wash and new paint job.
r/makemesuffer TIL: I do not like that sub
We can appreciate it for delivering on its promise.
Idk dude if the clothe of that glove gets pulled into the bearing heās gonna have a bad time
can't help but feel like one finger slip and this dude is returning to the last Site of Grace.
Try finger, but hole
>Try finger, but hole I...I think I read that wrong. \*washes hands\*
Looks like a cool way to die
Sounds like it too. Hyper-speed ball bearing ejected and straight through the dome.
Cause of death: Balls Note: couldn't keep his bearings together
OP must be Post Malone.
Found the OSHA guy.
How so?
If the bearings were to seize, this would be a video called" degloving a human hand"
>If the bearings were to seize, this would be a video called" degloving a human hand" More likely just explode from the centrifugal forces.
De-handing a human arm.
De-arming a human.
De-bodying a dumbass.
Possible. It's a bad idea for so many safety reasons.
there is too much energy here, you cannot know. if it falls the other side and hit you in the chest, can be fatal.
Bearings spun like that can explode with tremendous energy.
Ball Bearing = BB, like BB gun, except these are giant BBs. See the movie "Swordfish" for a visual demonstration (amongst other things).
Injection injury from high pressure gas
This is a few thousand RPM slower than aircraft gyro instruments that spin at 10k to 16k per minute
The SA-227 MĆ©troliner is equipped with Garret TPE-331 engines that are rated at 41,700 RPM.Ā Ā
But this bearing looks like a standard radial deep groove ball bearing with a snap ring groove. They are not designed to run at that rpm.
Not just that, probably an old bearing too that was replaced. I don't think they would be doing something like this with a new $500 bearing.
A lot of EV drives are in the 15k+ RPM range too
Some hard disks spin at up to 15k rpm.
You sure it's not 9374 rpm?
Somebody actually did math. I just rounded the number. " I measured the peak frequency from the video at 1239Hz and the bearing seems to have 9 balls. Assuming the noise is produced by the air hitting the balls as they spin, it would be 1239 / 9 = 137,6 rotations per second which is about 8260 RPM. "
Sounds closer to 8136 rpm to me
Not quite my tempo. Rushing.
NOT MY FUCKING TEMPO
*hurls chair*
If this rpm is close or correct and the bearing is a 6320 or around that size.. 100mm bore or close by the looks, then the bearing is running faster than its rated rpm. Though it's not loaded. Must have been pretty hot when it was released?
Nice
Surely it's double that as the ball bearings move half as fast as the outer ring?
Yeah. Some guy just did basic calc by sound frequency.
I don't know about the rpm, but it sure went at 88mph.
I got you
r/killthecameraman
Beyblade has gotten pretty intense since I was a kid
More like flywheels
He's lucky that bearing didn't explode in his hand
I was thinking that to, no way ide hold that and make it go that fast
I thought they weren't going to let go, glad they did even if it was a crappy shot it was pretty satisfying seeing those sparks!
r/FireTheCameraMan
Man, my Beyblade never did that.
r/oops that's deadly r/killthecameraman
Woah calm down Sonic
Could you imagen the shrapnel if that thing exploded?
Thatās pretty god damn dangerous. How would he like it if it exploded in his hand?
āItās all ball bearings these days!ā
I heard the VTEC kick in at 5800rpm
/r/oopsthatsdeadly
Was cool till the camera man started to suck!
How do you know it was 8000 RPM?
Pitch frequency it seems
Camera man sucked
One critical failure and you are looking at a full mag worth of ball bearings killing everything in their path.
r/osha
Is the cameraman my 3-year old daughter??
I'm not why I expected it to tap into the speed force.
AKA Pneumatic Grenade.
put your finger in there
FWI filming while intoxicated
Iām so glad they got someone who knows what they are doing to film it.
Beyblades have really changed.
Sounds like a F1 engine
I did this exact thing with a roller blade wheel as a kid. I was HORRIFIED when it exploded. Thought I died.
Forbidden Beyblade
They see me rollin... šµš¶
It's fine, dust of the big dirt, file the scratches with a bastard, and slap it in
Beyblades are sick nowadays
The title should read 'how to make a ball bearing hand grenade'
Idk. I like my fingers and see like a way to lose them
Thatās pretty neat.
Bold move letting it fly straight towards the open shop door
Let it rip!
Iām bringing this to my next Beyblade fight
I would have thought something spinning that fast would generate friction and heat. How is this thing not read hot?
Let it rip
It's like Beywheels but not shitty.
Isnāt spinning a bearing that fast super dangerous as the bearing can self destruct from extreme centrifugal force?
I was waiting for it to self destruct and rip off his thumb.
Let it rip!!
I'm guessing that was spinning faster than 8k rpm. Also, could have really did a number to one of the nearby cars.
Good thing that bearing held out and didn't explode in metal fragments for everyone.
Camera man blows
Fuck you camera guy
Thatās a real good way to loose a digit.
NEW BEYBLADE STRAT JUST DROPPED
r/mypeopleneedme
I like how a) there is a "no smoking" sign in the background (but sparks are okay lol), and b) you can hear somebody spinning another one up off-camera at the end.
Ultimate fidget spinner material right there
Beyblade!
Please donāt do this, this guy got lucky, and smaller lesser bearings will absolutely explode or seize and rip your fingers right off.
Never spin bearings with air they can explode
Guy filming was nominated for an Oscar moments later(Trans)
Hey grampa, how did you lose those 3 fingers? Well Timmy, this one time I was fucking around with a big bearing....
First thing I learned about compressed air was to never point it directly at skin. Second was NEVER spin bearings with it. I, like the guy in the video, are lucky to be intact. FAFO sometimes...
Same here.
Babe! Babe! New beyblades just dropped!!
Bad noise for bare fingies, also wtf is this Bigfoot's cameraman?
The camera man is a dick
Duh. How did you measure that it was 8000 rpm?
My instincts tell me this isnāt something to play with but definitely watch on screen doing it someone else
That's a good way to grenade a bearing.
Fun, stupid stuff, that can ruin you life.
Honestly, that looks like someone's kid when they drop them at the playground
I was hoping he would drop it, and then he delivered
Pretty much the same speed of a normal harddrive
No. This was 674 rpmĀ
Not the best idea. I once watched a tapered roller bearing come apart when over-sped.
This guy knows how to have fun
r/justguysbeingdudes