There must be tri-stable mechanisms out there, too.? Btw. Brucelee's one-inch punch uses the same over center movement in the moment of impact to create an force spike.:)
I don't know anyone else who could make it almost 27 minute video about what's basically a fancy hinge and still manage to make it so incredibly entertaining that I was sitting on the edge of my seat waiting to see the next mechanism.
I work in injection molding factory, matter of fact, making fliptop caps. I trust your story of how the bi-stable hinge was discovered. Actually, we had one cap which, if you opened it from another angle than it was intended to, the spring of the hinge snaped. One day, the mold flashed around the hinge and we discovered it made it more resistent. You could open the fliptop cap in a 45 degree angle from the front and the hinge didn't snap. That "failure" was success, and since then we made all cavities with that intentional flash. PS: I truly thank you for explaining the by-stable mechanism, specially the triangle principles. I work with these for more than 2 years and NOW I GET IT. Thank you ♥
they probably came from evolutions to compliant mechanisms one of the first compliant mechanisms was basically vicegrips, all of the early designs seem to play with this over center mechanism design, now more complex compliant mechanisms are made like the titanium hinge that don't require a binary mode of operation
I simply love knowing that there is a big enough community out there willing to hear a guy nerd out about over center mechanisms for almost 30 minutes. 😍
I've been machining for 93 years. This is how I always done it. It's how my daddy did it. It's how my daddy's daddy dit it. Great to see that technique memorialized here on the world wide web video machine.
@@dustysrandom5079 Ill be honest, the only reason i made the comment is because its likely really easy to miss and I was super early haha. Jokes too good to sit idle haha
@@jaredknapp8886 I mean, in all earnest, theres no reason a forstner bit couldnt be used in aluminum. You route aluminum with HSS bits all the time; and drill it all the same. The issue would be torque and it "Grabbing" or potentially work hardening the aluminum, but I think thats purely a feed and speed thing.
IKR? I don't care if it's cliched. As the youngest of my family, recently watching another one of my nieces graduate high school while memories hit me of my brother bringing her older cousin with him weeks after her birth to pick me up from the same school couldn't be more surreal. It's like, no, you're supposed to stay adorable and small forever. Stop it. And now I've turned into my mom 😂
This is the absolute best over-center video I have ever seen! OK, it is the only over-center video I have seen, but it is still the best. Thanks, Tony, for another gem!
Love the video - information, insight, humor - everything. The plastic cap hinges are called “living hinges”- (I’m sure Tony will have some fun with this term.) A factoid I learned in industrial design school is that some plastic living hinges must be flexed (cycled) shortly after being injection molded in order to preserve the flex of the hinge. If this is not done, the hinge becomes brittle, reducing the number of cycles/life. This was accomplished by ejecting the part against a baffle which caused the part to close. But, this was 40 years ago, so this process might not be current. Absolutely LOVE all of Tony’s work! Thank you!
26:12 "I don't know who this video is for..." Me. "...who needed to see it..." Also me. "...or what they might do with it..." Absolutely nothing, except enjoy it, obviously.
First two spot on but for the third it will come in useful to me sometime probably; if for nothing else then sitting around drinking wine explaining bi-stable states, because of some tangent the conversation has gone off on, and being able to grab the ketchup to explain it.
The crazy thing is that I was I middle of making a TV mount for the roof of my truck and I wanted it to go up and down by itself basilly with a gas shock to assist it. I was not even looking for designs or anything like that on UA-cam when I got the notification of this video and I didn't even understand the title either just hit play because it's Tony!! Watching this has made me think of a perfect layout to build now!! Talk about perfect timming!! I am that person this video was made for!! Thanks Tony!!
You know, watching this video made me realize that Tony probably has a side gig where he makes video's for science and shop teachers that are too hung over to teach class that day. All they have to do is take attendance, turn off the lights, play the video, and sleep until the bell.
I thought he was trying to break it to us that he was leaving us to go teach grade school. This was an impressively comprehensive and understandable breakdown.
I'm 50 years old but watching that video made me wish we saw stuff like this in school. Thorough explanations, accurate nomenclature, excellent video work, a few jokes to keep you paying attention... TOT is GOAT! (That stands for "greatest of all time", for those of you who are my age or older.)😅
25:52 I feel personally attacked. btw Tony, I started watching your videos as a sophomore in college and I'm 3 years in the industry now. Things I learned from your videos allowed me to effectively lead my senior design project because almost all the other kids had no hands on experience. I really appreciate that you have the interest in doing this. It's probably more valuable than we all realize.
A machinist named Tony's so neat, His videos are always a treat. When he posts something new, I can't help but woohoo! His return makes my joy quite complete!
I always go looking for the limerick in the comment section. I don't even know if you're the one that always does it, or if it's just a ToT Community thing that limerick-capable people take turns, depending on who shows up first.
Excellent. If my father had this conversation with me when I was at the age of asking difficult questions, my life would have been different. Thanks Old Tony.
The "sorta-stable" state is known as an "unstable equilibrium" state. Meaning, it is a condition where no net force exists (therefore no motion initiated) but not stable, since a small force will upset the arrangement. Just like how you can balance a rod on its end but it will inevitably fall over and assume a stable equilibrium eventually.
I _knew_ it - ToT showers with tomato sauce! These videos are now not just machining, entertainment… they are Art! Library of Congress, you got to add these!
Awesome timing; the other day I was watching a tow truck operator hooking up an F-150 that had dropped its differential in front of my building. When he came to install the pair of tandem trailering wheels around the immobile back wheels of the pickup, I watched him use a long rod to lever the cradle up and over centre and leave the truck locked by gravity into place four inches above the ground and I was struck by just how utterly brilliant yet gloriously simple that invention was. And now here you are, teaching me all about the concept in yet another amazingly well scripted, filmed, edited and executed video. This is exactly the kind of stuff for which UA-cam was invented!
Being a plastics process technician, I believe you are absolutely correct with your first theory of invention. Great video Tony, nice to have lunch with you!
I taught theory of machines and mechanisms and this is just perfect! It is the type of videos that get students interested in the subject. It brings the semantic gravity of it all to real-life level where they can observe these mechanisms and learn in and around their own homes. Thank you so much for the passion and effort you put into your videos!
It just occurred to me that I haven’t experienced this same cocktail of wonder/awe/laughter since watching James Burke’s Connections series on PBS back in 1978. Thank you, I’ve been missing it
Just to mention the effort that videos of this quality must take to make... the wits, the attention to detail, the script... the little silly things on the side. I am always amazed.
26 minutes and I'm still glued to this concept - I'm a maple producer, I make maple syrup in a saphouse in my backyard - and the windows in the cupola up on the roof have to be opened and closed when in use - they are 14ft off the ground, and it took a bit of figuring, but I was able to use an over center mechanism to help them start to move from vertical to nearly horizontal. Great video!
24:48 His name was Ed Furst. He worked for Black Clawson. Also brought you the iconic plastic Ivory Snow bottle and the hole through the neck detergent (and other liquids) bottle handle. The man was a genius.
I mean this with all my heart and soul. My eyes light up like its chirstmas when i see a new video uploaded. Your sense of humor super smartness is one of a kind. I would love to meet you one day. Just to sit down and talk shop. Thank you for everything. Tony, you are seriously my hero.
@@gwcstudio I know how exactly how to use the bit to achieve concentric convex radius around the pivot hole, as seen. Seriously It's just that he edited out the boring manual stages to get there. Makes the video snappy.
Next time you watch a video of aircraft mechanics "swinging the gear" on a large airplane while it is suspended on jacks, look closely at all the struts, links, hooks and springs that come into view. You will see many over center mechanisms, and they are the devices that securely lock the gear into either the retracted or extended position. Once moved into the over center lock position, the gear will stay in that position even if hydraulic pressure is lost. If hydraulic pressure is lost in flight while the gear is retracted, simple mechanical or pneumatic devices can be actuated to move the up locks over center and allow gravity to do the job of lowering the gear and locking it down with spring-loaded over center mechanisms for a safe landing.
@@GordieGii Yes and yes. The most common device is two struts, or links, one hinged to some part of the gear or gear door, and the other hinged to structure. The two struts are hinged together at the free ends such that they can fold In one gear position, but form a straight line in the other (either gear extended or gear retracted). One of the struts will have some extension on the end that contacts the other strut just as the joint goes slightly over center, preventing any further movement, while springs prevent any movement back toward center. On several aircraft types, the nose landing gear has struts arranged so that they over center and lock in both the extended and retracted position. Main landing gear usually has an over centering hook mounted on structure that catches a roller bearing attached to the shock strut to hold the gear in the retracted position, while the end-to-end side strut arrangement locks it in the down position.
@@Hopeless_and_Forlorn So for the nose gear the short strut rotates around 182 degrees (relative to the medium strut) acting like a toolbox catch in the retracted position and the toggle clamp in the extended position. (1 deg over center at each end) Very cool.
I just discovered TOT last week. Watching him explain a pivot is like witnessing the dawn of pre history as humanity learns about the pivot for the first time. From a mysterious monolith of course. This channel is the best and funniest thing I have watched in ages... Toby’s love of spring pistons is inspirational.
Not going to lie here, I've used Forstner bits on aluminum. Why? I was installing a lock on an aluminum faced, wood core door. The circumferential cutters made very clean edges on the aluminum. Then the remaining wood was easily removed. Door had aluminum on both faces, a small pilot hole aligned for both sides.
Excellent video! I am a mechanical engineer and am very familiar with over center mechanisms but I thoroughly enjoyed this video. You did such a great job explaining the concept I made both my boys watch it so they would understand the concept being aspiring engineers themselves. Great job. Always love when you drop a new video.
Hard to articulate why in a UA-cam comment, but this video just made a project idea I had not only easy and possible, but it will cost me at least $1000 less. Genuinely thank you SO MUCH educated-hands-with-disembodied-voice-man.
As a truck driver; my favorite over-center-mechanism is a lever action chain binder. Outlawed in a few states due to how much force it can pack, but sure can make a chain tight in seconds with some mechanical advantage help from a cheater bar!
Yeah those things are awesome. Hook one up snug, pull down hard and "PWIIING!" snaps in. I had no idea those would be illegal, what was happening that convinced the states to outlaw them?
@@wellscampbell9858 They have a tendency to come loose on rough roads, let alone the "knock your teeth out" factor when taking them off, or putting them on when you have too much tension to get them to over center.
Working in the north Atlantic as a deck hand we would tie the handles to the rest of the binder with tarred marlin. Never had one come loose. Had chains break though. Cheater bars were outlawed though.
Too many people aren't smart enough to know you shouldn't stand in front of it and pull it towards yourself. Especially with a cheater it will punch right through your ribs, teeth, eye socket. You have to push it from behind and try not to let it drag you off the trailer when it goes😂
I’m native Spanish speaker and the name of this system has been eluding me for years. I once watched how this is achieved when I was first learning English but forgot the name of that particular system until today. Thank you very much.
Perfect timing. I'm replacing the horrific spring mechanism on my 4x6 Harbor Fright bandsaw with a gas spring. I feel like I'm grabbing a porcupine every time I try to tighten or loosen it. It's like an engineer said "How can we make this saw worse? I know, let's add a bunch of tiny little needles to the spring handle." Now I'll better understand what the heck I'm doing, how the over center mechanism works. And I won't draw blood every time I need to use the saw. Thanks Tony!
Damn man, I don't think you realize how amazing your videos are. Your skills in mechanics, humor, storytelling, videomaking and all other stuff that goes into these videos are AMAZING.
I gotta agree. That video was 30 minutes. And only about what we all learned in high school physics. But he made it "fun" and "interesting". And I will probably watch it again cuz I'm gonna show my dad. Well done.
The only maker that makes me stop whatever I’m doing and watch as soon as I see the notification. It’s like a surprise present from a friend! Keep it up Tony!
I've been watching these videos for so long, that I've gone from being mystified and excited about concepts, to intuiting mechanics naturally, to being able to calculate them in linear algebra. I don't just see the mechanism anymore, I see state vectors of material strengths, stress graphs, dynamic free body force diagrams. When I see mechanisms like this I think about how I want to implement them as trajectoid rolling cam capstan tension joints, milled on compound differential machines, blah blah blah. I naturally jump to calculus solutions even when algebra is sufficient. I'm working on moving back towards simplicity, I want to find the gauge symmetry solution to every problem I encounter, instead of the convoluted, eclectic, un-implementable nonsense I come up with at first blush. Wherever I end up in the future, I just wanted to say you've been a major part of my journey. Textbooks seem to put absolutely no effort into motivating the problem solving processes. So in my opinion, these videos are uniquely valuable. I am deeply grateful for the incredible amount of effort it must have taken to make them over these long years.
Thanks TOT, your clear explanation of over centre locking systems has allowed me to undo the nipple clamps I’ve had stuck to me for the last 3 days. Phew!
Tony if you read this, I just want to thank you so much for sharing these videos with us, they are always such a joy. The work you put into them really shines through. I’m no good with words so I can’t properly articulate my appreciation for you. You have truly mastered the art of the creative, humorous, educational video for the nerds like me who like working with their hands.
The "The engineering guy" orientation mixed with your style is fantastic. How a simple common mechanism works explained in a very very simple way. Fantastic.
I knew a guy called TOT . Used to make some pretty good UA-cam videos ... not seen him for a while now but they say , on cold dark nights when the wind blows from the west , you can still hear the faint sounds of informative light hearted educational videos wafting through the trees .. :)
I live for your videos. I don't understand the things you talk about but I learn new things every time! As a lowly HVAC guy these are amazing. The presentation and humor make every single one of these special and for that, I thank you Good Sir!
I'm thinking that after the video ended, he hit the stop button on the camera, TOT leaned back in his chair, kicked his metal shaving laden shoes up on the bench, and told his headless son with a rasp - blowing a blue shop-smoke ring through lips aged by wisdom and honed with wit, "That's how it's done, son. You'll have to do better than, 'yeah'".
Good job you put that 'un-pause now' hint in there otherwise I'd still be sat here staring.... what am I talking about, we're only a quarter of the way in so I'm still staring. 🤣
When I added this to my watch later list, I wasn't sure why I needed to see it or exactly what I would learn. Cut to me actually watching a video on my watch later and you filled in a mystery blank area of knowledge I didn't know I had. Thanks!
Glad you're back TOT. You're videos are perfect - practical, informative, educational and humorous - no matter what the subject matter is. If someone asked me if I'd like to watch a video on over center mechanisms, I would think he /she had lost their minds. Now, mention that the video was done by TOT and I'll sell my Taylor Swift tickets to get a better seat watching TOT's video.
Super cool to hear Tony talk about bi-stability after having taken a college course on compliant mechanisms. A fun fact about the snap-caps is that the industry standard has basically been trial and error since their inception to get the right amount of "snap" since we didn't have a way to nicely model the situation. In the past 20 years or so some new methods have come out to actually design that sort of stuff mathematically which is what my course was on.
Yea its crazy how far tech has come. Like I still feel very young, but i did my undergrad in nuclear engineering and material sciences in the early 00s. Modeling and simulation are just... far beyond anything i studied o.O I remember modeling a fluid boundary layer back then and it took literally all night to render a few seconds. My PHONE could do it exponentially faster these days lol
I learned about bi-stability when I was learning electronics, the venerable 555 can be configured to be bi-stable. I most often used the 555 as a metastable multivibrator tho.
A great class on simple mechanisms, with a lot of engineering involved. All with the magic of a master in examples and joy in explanations. Thank you very much.
OUTSTANDING!!! I love this kind of videos! The history and all the stories behind some of what we consider to be basic mechanical principles that helps us all in everyday! This was quite a treat! THank you and greetings from Portugal.
"Some might even argue they create force because they change length" is a very interesting shower thought :) i guess i am someone who this video was for
i fixed a lot of spring loaded hinges, never given it a second thought that they were loaded with different springs or that the mechanism had a name, thanks Tony for filling up that gap in my knowledge.
Give a raise to the mysterious guy yelling from the other side of the room, he knew all the answers 😮
He's just there because of the lathe. He watched it next week but realized that yelling at the screen doesn't actually work.
He wasn’t on the other side of the room, he was over-centre. Weren’t you paying attention ??
That's the guy who keeps stealing the script. That's also why he seems to know all the answers.
There must be tri-stable mechanisms out there, too.?
Btw. Brucelee's one-inch punch uses the same over center movement in the moment of impact to create an force spike.:)
@@GodzillaGoesGaga Best comment award winner
I'm glad you used a Sharp calculator. Statistically, Blunt calculators cause far more injuries.
that was a good one
That WAS a good one!
Look up the statistics on lefties using right-handed calculators it'll send chills down your spine!
That's %100 grade A, Tony certified jokeage right there, buddy. I _really_ hope he sees this.
Real engineers use an HP calculator with RPN (Reverse Polish Notation).
I don't know anyone else who could make it almost 27 minute video about what's basically a fancy hinge and still manage to make it so incredibly entertaining that I was sitting on the edge of my seat waiting to see the next mechanism.
So true, and well put.
@@grumpyone5963 take my upvote sir!
I've said before, I would watch him if he were talking about knitting
Didn't realize I spent 27 minutes enthralled in this until I scrolled down here
Isn't it just an acute triangle with longest side a compression or tension spring?
I work in injection molding factory, matter of fact, making fliptop caps. I trust your story of how the bi-stable hinge was discovered. Actually, we had one cap which, if you opened it from another angle than it was intended to, the spring of the hinge snaped. One day, the mold flashed around the hinge and we discovered it made it more resistent. You could open the fliptop cap in a 45 degree angle from the front and the hinge didn't snap. That "failure" was success, and since then we made all cavities with that intentional flash.
PS: I truly thank you for explaining the by-stable mechanism, specially the triangle principles. I work with these for more than 2 years and NOW I GET IT. Thank you ♥
There, you see:
another one sucked into the vortex that is Tony's mind.
We've been waiting....
bi-stable
they probably came from evolutions to compliant mechanisms one of the first compliant mechanisms was basically vicegrips, all of the early designs seem to play with this over center mechanism design, now more complex compliant mechanisms are made like the titanium hinge that don't require a binary mode of operation
@@MrMetricSystem binary mode? vs ASCI or text?
its a hinge, not computer programming...
Poly tops ?
I simply love knowing that there is a big enough community out there willing to hear a guy nerd out about over center mechanisms for almost 30 minutes. 😍
Wait! Didn't you read the user agreement?
he is just entertaining the masses with the ideas that rattle most of our brains if you look at things close enough
Its all a ploy by ToT to flesh out the 5mins of explaining the uber cool one piece flip top caps 😜
Drop everything, it’s this old Tony!
YESS!!!
Done and done
And I mean DONE!
I did immediately!😂
Work can wait!
the forstner bit making the ends round is pretty funny lol
I had to run that back to make sure I wasn’t missing something. 😆
I've been machining for 93 years. This is how I always done it. It's how my daddy did it. It's how my daddy's daddy dit it.
Great to see that technique memorialized here on the world wide web video machine.
@@dustysrandom5079 Ill be honest, the only reason i made the comment is because its likely really easy to miss and I was super early haha. Jokes too good to sit idle haha
I thought that was a bit made for wood. Tony is up to his tricks.
@@jaredknapp8886 I mean, in all earnest, theres no reason a forstner bit couldnt be used in aluminum. You route aluminum with HSS bits all the time; and drill it all the same. The issue would be torque and it "Grabbing" or potentially work hardening the aluminum, but I think thats purely a feed and speed thing.
Hearing your boy is a preteen has given me another dozen gray hairs. Seems like yesterday he was 3 years old and "helping" build your CNC router.
thats because thats the last time he made a video.
IKR? I don't care if it's cliched. As the youngest of my family, recently watching another one of my nieces graduate high school while memories hit me of my brother bringing her older cousin with him weeks after her birth to pick me up from the same school couldn't be more surreal. It's like, no, you're supposed to stay adorable and small forever. Stop it. And now I've turned into my mom 😂
I know right? I was like 'shit she's a teenager?'
"Building my son his first car"
@@custos3249 IKR? Oh wait... you use emojis. Not the brightest knife in the drawer.
"Jars feel that same exact pain every time you close them"
Tony really keeping up on that mild psychological horror. Never change.
As a student civil engineer this has been quite a revelation! Thanks Tony, what a lesson :D
This is the pinnacle of UA-cam content and formatting. It will never get better than this.
That's what they said about the Zeppelin...
@@GordieGii and how did that go over? Like a, well, Le(a)d Zeppelin.
yeah youtube just peaked
@@ken481959
The lead zeppelin never got off the ground.
But the Hindenburg was really popular. You could say it was on fire.
@@GordieGiiand did it? I can't think of anyone who did what zeplin did better...
I chickened out when my kids asked about over-centre mechanisms, and I just gave them the book "Where did over-centre mechanisms come from?".
That must've been a hard decision to make 😅😅😅
You see son, when mama part and daddy part love each other very much, they get... snappy
Followed by the page turner Compliant Mechanisms, by Larry Howell
This is the absolute best over-center video I have ever seen!
OK, it is the only over-center video I have seen, but it is still the best.
Thanks, Tony, for another gem!
Steve Mould has one that's mostly about him not knowing what they're called or how widely used they are. The comments took care of that, at least.
And it would still be the best, even if there were a thousand other videos about the topic!
There is no one else on Gods green earth that could have made over-center explanation this entertaining. Well done, young man.
Technology connections might’ve been able to, but not to the same extent as Tony
Love the video - information, insight, humor - everything.
The plastic cap hinges are called “living hinges”- (I’m sure Tony will have some fun with this term.)
A factoid I learned in industrial design school is that some plastic living hinges must be flexed (cycled) shortly after being injection molded in order to preserve the flex of the hinge. If this is not done, the hinge becomes brittle, reducing the number of cycles/life.
This was accomplished by ejecting the part against a baffle which caused the part to close.
But, this was 40 years ago, so this process might not be current.
Absolutely LOVE all of Tony’s work!
Thank you!
This video has changed my life and I cant explain it to anyone without sounding like a crazy person.
Congratulations; your "spring" is set, and you are now ready to proceed Over Center...
26:12
"I don't know who this video is for..." Me.
"...who needed to see it..." Also me.
"...or what they might do with it..." Absolutely nothing, except enjoy it, obviously.
First two spot on but for the third it will come in useful to me sometime probably; if for nothing else then sitting around drinking wine explaining bi-stable states, because of some tangent the conversation has gone off on, and being able to grab the ketchup to explain it.
"And now, we're well on our way to hurting ourselves." 🤣
The crazy thing is that I was I middle of making a TV mount for the roof of my truck and I wanted it to go up and down by itself basilly with a gas shock to assist it. I was not even looking for designs or anything like that on UA-cam when I got the notification of this video and I didn't even understand the title either just hit play because it's Tony!! Watching this has made me think of a perfect layout to build now!! Talk about perfect timming!! I am that person this video was made for!! Thanks Tony!!
I've dated a couple bistable mechanisms... You're a great dad keeping your kids and all the other kids in the world informed 🙌
You know, watching this video made me realize that Tony probably has a side gig where he makes video's for science and shop teachers that are too hung over to teach class that day. All they have to do is take attendance, turn off the lights, play the video, and sleep until the bell.
Isn’t that just his normal channel
There's a reason he never gives us face time.
I thought he was trying to break it to us that he was leaving us to go teach grade school. This was an impressively comprehensive and understandable breakdown.
I'm 50 years old but watching that video made me wish we saw stuff like this in school. Thorough explanations, accurate nomenclature, excellent video work, a few jokes to keep you paying attention... TOT is GOAT! (That stands for "greatest of all time", for those of you who are my age or older.)😅
@@rm3141593I would buy a DVD set of all basic and intermediate mechanical mechanisms described like this.
You just held our attention, volunteeraly, for 26:40... explaining over center...👏👏👏
Finally. Like the first sip of refreshing water after a long dry spell
25:52 I feel personally attacked.
btw Tony, I started watching your videos as a sophomore in college and I'm 3 years in the industry now. Things I learned from your videos allowed me to effectively lead my senior design project because almost all the other kids had no hands on experience. I really appreciate that you have the interest in doing this. It's probably more valuable than we all realize.
Trying to figure out how it works on your own in the shower is difficult. You're a good Dad Tony.
A machinist named Tony's so neat,
His videos are always a treat.
When he posts something new,
I can't help but woohoo!
His return makes my joy quite complete!
Now a update on project binky and my year is good 😊
Burma Shave
ehhh.....8.5 👍
I always go looking for the limerick in the comment section. I don't even know if you're the one that always does it, or if it's just a ToT Community thing that limerick-capable people take turns, depending on who shows up first.
That didn’t sound gay at all.
Excellent. If my father had this conversation with me when I was at the age of asking difficult questions, my life would have been different. Thanks Old Tony.
lol, thanks pete!
The spring hitting the center screw actually benefits the mechanism. It makes the "sorta-stable" position in the middle virtually impossible.
Also an awesome sound.
Better with a button headed cap screw though :-)
The "sorta-stable" state is known as an "unstable equilibrium" state. Meaning, it is a condition where no net force exists (therefore no motion initiated) but not stable, since a small force will upset the arrangement. Just like how you can balance a rod on its end but it will inevitably fall over and assume a stable equilibrium eventually.
The writing is on a level with the science. Good hands! GOOD BOYS!
I _knew_ it - ToT showers with tomato sauce!
These videos are now not just machining, entertainment… they are Art! Library of Congress, you got to add these!
Great to see you back 👍
I heard that it was chamfers that separate us from the animals 🙂
That’s what Quinn tells us.
and sometimes fences as well :D
As is tradition
When it comes to chamfers you don’t want to cut corners 😀
@@kenharper5755 That's a bit edgy, don't ya think?
Awesome timing; the other day I was watching a tow truck operator hooking up an F-150 that had dropped its differential in front of my building. When he came to install the pair of tandem trailering wheels around the immobile back wheels of the pickup, I watched him use a long rod to lever the cradle up and over centre and leave the truck locked by gravity into place four inches above the ground and I was struck by just how utterly brilliant yet gloriously simple that invention was. And now here you are, teaching me all about the concept in yet another amazingly well scripted, filmed, edited and executed video. This is exactly the kind of stuff for which UA-cam was invented!
100%!
Being a plastics process technician, I believe you are absolutely correct with your first theory of invention.
Great video Tony, nice to have lunch with you!
I taught theory of machines and mechanisms and this is just perfect! It is the type of videos that get students interested in the subject. It brings the semantic gravity of it all to real-life level where they can observe these mechanisms and learn in and around their own homes. Thank you so much for the passion and effort you put into your videos!
It just occurred to me that I haven’t experienced this same cocktail of wonder/awe/laughter since watching James Burke’s Connections series on PBS back in 1978. Thank you, I’ve been missing it
Just to mention the effort that videos of this quality must take to make... the wits, the attention to detail, the script... the little silly things on the side. I am always amazed.
ToT is just over center, into one of a kind.
26 minutes and I'm still glued to this concept - I'm a maple producer, I make maple syrup in a saphouse in my backyard - and the windows in the cupola up on the roof have to be opened and closed when in use - they are 14ft off the ground, and it took a bit of figuring, but I was able to use an over center mechanism to help them start to move from vertical to nearly horizontal. Great video!
I didnt know they had a name, now I can talk about them properly, excellent.
You Rock ToT! I would love to see a collaboration between you and The Engineer Guy.
24:48 His name was Ed Furst. He worked for Black Clawson. Also brought you the iconic plastic Ivory Snow bottle and the hole through the neck detergent (and other liquids) bottle handle. The man was a genius.
I mean this with all my heart and soul. My eyes light up like its chirstmas when i see a new video uploaded. Your sense of humor super smartness is one of a kind. I would love to meet you one day. Just to sit down and talk shop. Thank you for everything.
Tony, you are seriously my hero.
thanks rob!!
You know it's going to be a great weekend when TOT posts! Don't turn that contraption upside down because all of the gravity will fall out.
The Forstner bit gag at the beginning is easily missed but brilliant. I wish making an external radius was that simple. 😊
Whats the joke please whats a forstner ?
The round cutter, which normally makes clean holes, not radius cuts
I had to go back and watch it again. A "UA-cam double-take."
Also how the toggle lock in a lever action rifle works.
@@gwcstudio I know how exactly how to use the bit to achieve concentric convex radius around the pivot hole, as seen. Seriously
It's just that he edited out the boring manual stages to get there. Makes the video snappy.
On the opening, The dial tone automatically triggered my brain to the lyrics “I need your arms around me I need to feel your touch”
Probably my favorite video on the internet.
These educational videos are 10/10. Even if it's a concept you already know, you always pick up something new. 10/10, LOVE THESE.
Next time you watch a video of aircraft mechanics "swinging the gear" on a large airplane while it is suspended on jacks, look closely at all the struts, links, hooks and springs that come into view. You will see many over center mechanisms, and they are the devices that securely lock the gear into either the retracted or extended position. Once moved into the over center lock position, the gear will stay in that position even if hydraulic pressure is lost. If hydraulic pressure is lost in flight while the gear is retracted, simple mechanical or pneumatic devices can be actuated to move the up locks over center and allow gravity to do the job of lowering the gear and locking it down with spring-loaded over center mechanisms for a safe landing.
Is it two separate over-center devices, or did some genius come up with an arrangement that had two centers?
@@GordieGii Yes and yes. The most common device is two struts, or links, one hinged to some part of the gear or gear door, and the other hinged to structure. The two struts are hinged together at the free ends such that they can fold In one gear position, but form a straight line in the other (either gear extended or gear retracted). One of the struts will have some extension on the end that contacts the other strut just as the joint goes slightly over center, preventing any further movement, while springs prevent any movement back toward center. On several aircraft types, the nose landing gear has struts arranged so that they over center and lock in both the extended and retracted position. Main landing gear usually has an over centering hook mounted on structure that catches a roller bearing attached to the shock strut to hold the gear in the retracted position, while the end-to-end side strut arrangement locks it in the down position.
@@Hopeless_and_Forlorn So for the nose gear the short strut rotates around 182 degrees (relative to the medium strut) acting like a toolbox catch in the retracted position and the toggle clamp in the extended position. (1 deg over center at each end) Very cool.
Supposedly 😂. Unless it doesn’t 😮 😢
I'm so thrilled about that upcoming video about poop jar!
I just discovered TOT last week. Watching him explain a pivot is like witnessing the dawn of pre history as humanity learns about the pivot for the first time.
From a mysterious monolith of course.
This channel is the best and funniest thing I have watched in ages...
Toby’s love of spring pistons is inspirational.
Tony, I know I don't say this as much as I should, but you're THEE BEST!!!
For the last 63 years I never thought of 'over center ' now thanks to you I see it every where THANKS tot!
Thats Comedic sarcasm
@@311Bob Just because you're not paranoid, doesn't meant he over-centers aren't watching!
that forstner bit gag cracked me up
As a carpenter guy, that definitely threw me off, “is that aluminum? Do they even make metal forstner bits?!”😂
@@theothersergethe thing that threw me off was that it didn't look centered. 😂
@@Jehty_ right?! 😂
Not going to lie here, I've used Forstner bits on aluminum. Why? I was installing a lock on an aluminum faced, wood core door. The circumferential cutters made very clean edges on the aluminum. Then the remaining wood was easily removed. Door had aluminum on both faces, a small pilot hole aligned for both sides.
@@keithjurena9319 Are you sure it was aluminum and not steel? Aluminum that thin would dent very easily.
Really holds your attention, keeps you locked in
Excellent video! I am a mechanical engineer and am very familiar with over center mechanisms but I thoroughly enjoyed this video. You did such a great job explaining the concept I made both my boys watch it so they would understand the concept being aspiring engineers themselves. Great job. Always love when you drop a new video.
I don’t know why YT suggested this. But I am glad it did. Nice one, thank you👍
Hard to articulate why in a UA-cam comment, but this video just made a project idea I had not only easy and possible, but it will cost me at least $1000 less.
Genuinely thank you SO MUCH educated-hands-with-disembodied-voice-man.
As a truck driver; my favorite over-center-mechanism is a lever action chain binder. Outlawed in a few states due to how much force it can pack, but sure can make a chain tight in seconds with some mechanical advantage help from a cheater bar!
Yeah those things are awesome. Hook one up snug, pull down hard and "PWIIING!" snaps in. I had no idea those would be illegal, what was happening that convinced the states to outlaw them?
@@wellscampbell9858 They have a tendency to come loose on rough roads, let alone the "knock your teeth out" factor when taking them off, or putting them on when you have too much tension to get them to over center.
Working in the north Atlantic as a deck hand we would tie the handles to the rest of the binder with tarred marlin. Never had one come loose. Had chains break though. Cheater bars were outlawed though.
I've seen cheater bars thrown 50 feet in the air with those things!😬😲
Too many people aren't smart enough to know you shouldn't stand in front of it and pull it towards yourself. Especially with a cheater it will punch right through your ribs, teeth, eye socket.
You have to push it from behind and try not to let it drag you off the trailer when it goes😂
Looking at the light switch thinking "what's your over-center secrets" 😂
Probably some sort of cam pushing on some sort of a leaf spring.
Don't let your wife hear you talk like that. She's gonna be jealous, and all...
Technology Connections has a great video on exactly this (and explains why switches are designed to click)
I’m native Spanish speaker and the name of this system has been eluding me for years. I once watched how this is achieved when I was first learning English but forgot the name of that particular system until today. Thank you very much.
Perfect timing. I'm replacing the horrific spring mechanism on my 4x6 Harbor Fright bandsaw with a gas spring. I feel like I'm grabbing a porcupine every time I try to tighten or loosen it. It's like an engineer said "How can we make this saw worse? I know, let's add a bunch of tiny little needles to the spring handle." Now I'll better understand what the heck I'm doing, how the over center mechanism works. And I won't draw blood every time I need to use the saw. Thanks Tony!
Nothing better than laughing while learning something new. Thanks.
I like that subtle throw back to the goof who suggested the chuck could be locked by unlocking it.
I knew this comment would be here. Thank you
Damn man, I don't think you realize how amazing your videos are. Your skills in mechanics, humor, storytelling, videomaking and all other stuff that goes into these videos are AMAZING.
1.16M subs. He knows.
I gotta agree. That video was 30 minutes. And only about what we all learned in high school physics. But he made it "fun" and "interesting". And I will probably watch it again cuz I'm gonna show my dad. Well done.
This is the video I need. These mechanisms kept me awake at night and now I finally understand them
Hands down, you’re most interesting video ever. I’m gonna watch it again.
The only maker that makes me stop whatever I’m doing and watch as soon as I see the notification. It’s like a surprise present from a friend! Keep it up Tony!
I've been watching these videos for so long, that I've gone from being mystified and excited about concepts, to intuiting mechanics naturally, to being able to calculate them in linear algebra. I don't just see the mechanism anymore, I see state vectors of material strengths, stress graphs, dynamic free body force diagrams. When I see mechanisms like this I think about how I want to implement them as trajectoid rolling cam capstan tension joints, milled on compound differential machines, blah blah blah. I naturally jump to calculus solutions even when algebra is sufficient.
I'm working on moving back towards simplicity, I want to find the gauge symmetry solution to every problem I encounter, instead of the convoluted, eclectic, un-implementable nonsense I come up with at first blush.
Wherever I end up in the future, I just wanted to say you've been a major part of my journey.
Textbooks seem to put absolutely no effort into motivating the problem solving processes. So in my opinion, these videos are uniquely valuable.
I am deeply grateful for the incredible amount of effort it must have taken to make them over these long years.
Thanks TOT, your clear explanation of over centre locking systems has allowed me to undo the nipple clamps I’ve had stuck to me for the last 3 days. Phew!
Tony if you read this, I just want to thank you so much for sharing these videos with us, they are always such a joy. The work you put into them really shines through. I’m no good with words so I can’t properly articulate my appreciation for you. You have truly mastered the art of the creative, humorous, educational video for the nerds like me who like working with their hands.
Yes, thank you for in-depth explanation of this almost mythical mechanism!
7:28 a Welsh man once told me a sheep is like a spring. I never did get this, but now I know. Thank you 😆
That's why they bring them to the edge of a cliff.
...no... ...NO... 😅
The "The engineering guy" orientation mixed with your style is fantastic. How a simple common mechanism works explained in a very very simple way. Fantastic.
I can’t believe there was so much here that I didn’t even know that I didn’t need to know, but I am definitely a better person now that I do.
Are you sure? ;-)
Thank you for your service.
You Sir are a Great Teacher!
How can 26 minutes go by so quickly? Entertained, educated and greatly amused, it's a true wonderment for which I humbly thank you.
I remember in past episodes hearing him apologize for making a long episode, and thinking "Long? that wasn't... oh."
I'm honored to hear that you place our edification above and beyond your children's. Thank you.
Bound up like too much Olive Garden! Brilliant & worth every second. Highlight of my day.
This is exactly what I needed! Now I can install a rear hatch for the camper build. Thanks TOT!!!
never change Tony! this was great!
It was just yesterday I was thinking, man I miss a good ToT video, my prayers have been answered.
Same - maybe two - three days ago
Keep doing these...it's like Shop class for adults Very informational in a fun way...
I knew a guy called TOT . Used to make some pretty good UA-cam videos ... not seen him for a while now but they say , on cold dark nights when the wind blows from the west , you can still hear the faint sounds of informative light hearted educational videos wafting through the trees .. :)
Oh, I'm sorry, I had beans for lunch. Just crack the window open and it'll waft right out. 💨😊
I've had my fair share of education. You are one of the best teachers I've had. Thanks TOT!
I live for your videos. I don't understand the things you talk about but I learn new things every time! As a lowly HVAC guy these are amazing. The presentation and humor make every single one of these special and for that, I thank you Good Sir!
Same wonderful editing as always, same excellent humor, top notch narration and -- fascinatingly educational. Again!
Thank you, Tony!
And there I was thinking that TOT had snapped over his personal center... Thanks for coming back with such silky smooth content and hair.
I'm thinking that after the video ended, he hit the stop button on the camera, TOT leaned back in his chair, kicked his metal shaving laden shoes up on the bench, and told his headless son with a rasp - blowing a blue shop-smoke ring through lips aged by wisdom and honed with wit, "That's how it's done, son. You'll have to do better than, 'yeah'".
Good job you put that 'un-pause now' hint in there otherwise I'd still be sat here staring.... what am I talking about, we're only a quarter of the way in so I'm still staring. 🤣
When I added this to my watch later list, I wasn't sure why I needed to see it or exactly what I would learn. Cut to me actually watching a video on my watch later and you filled in a mystery blank area of knowledge I didn't know I had. Thanks!
Glad you're back TOT. You're videos are perfect - practical, informative, educational and humorous - no matter what the subject matter is. If someone asked me if I'd like to watch a video on over center mechanisms, I would think he /she had lost their minds. Now, mention that the video was done by TOT and I'll sell my Taylor Swift tickets to get a better seat watching TOT's video.
Super cool to hear Tony talk about bi-stability after having taken a college course on compliant mechanisms. A fun fact about the snap-caps is that the industry standard has basically been trial and error since their inception to get the right amount of "snap" since we didn't have a way to nicely model the situation. In the past 20 years or so some new methods have come out to actually design that sort of stuff mathematically which is what my course was on.
Yea its crazy how far tech has come. Like I still feel very young, but i did my undergrad in nuclear engineering and material sciences in the early 00s. Modeling and simulation are just... far beyond anything i studied o.O I remember modeling a fluid boundary layer back then and it took literally all night to render a few seconds. My PHONE could do it exponentially faster these days lol
I learned about bi-stability when I was learning electronics, the venerable 555 can be configured to be bi-stable. I most often used the 555 as a metastable multivibrator tho.
How dare you teach me so much about this interesting subject? I came to be entertained, not to Learn AND be entertained!
A great class on simple mechanisms, with a lot of engineering involved.
All with the magic of a master in examples and joy in explanations.
Thank you very much.
OUTSTANDING!!!
I love this kind of videos! The history and all the stories behind some of what we consider to be basic mechanical principles that helps us all in everyday!
This was quite a treat!
THank you and greetings from Portugal.
"Some might even argue they create force because they change length" is a very interesting shower thought :) i guess i am someone who this video was for
I would say they create force because they CAN change length but don't want to.
Commenting because engagement and everybody loves a tot video
Aircraft landing gear rely on "over-center" mechanisms to "lock" down and into place. Yet another amazing application of this mechanical concept.
are you a pilot?
@@jaredstoll2169 That would be a yes!
A transport Chain Binder is a simple example of an over center mechanism .
Very Well Done Explanation !
i fixed a lot of spring loaded hinges, never given it a second thought that they were loaded with different springs or that the mechanism had a name, thanks Tony for filling up that gap in my knowledge.
LMAO at the peanut gallery responses in the background. Perfection.