Circular Saw Kickback Killer (We used science to make tools safer) - Smarter Every Day 209

  • Published on Feb 17, 2019
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Comments • 6 167

  • Chad Green
    Chad Green 5 months ago +1842

    Also, #gonadularregion is safe!

    • Brian Landers
      Brian Landers Month ago

      ramzekeleviathan : You're right about using a wedge, but I would never use metal near a spinning circular saw blade, because that metal will go through safety glasses like a hot knife through butter. I really enjoy my eyes. Since you're working with wood, use a wooden wedge or plastic, since it's so abundant. I'm just saying.

    • Antonio Claudio Michael
      Antonio Claudio Michael 2 months ago

      @ramzekeleviathan knots in wood can cause kickback

    • jay dellinger
      jay dellinger 2 months ago

      @Schwurbel kickback is the result of the saw flinging wood or the saw it's self back or forward. 🤦

    • John Doe
      John Doe 3 months ago +2

      a riving knife or wedges are far simpler solutions. likely safer too as they wotn fail

    • Photon
      Photon 4 months ago

      This is a neat idea! If I may ask, what does the hardware look like on the inside of the saw? Does it somehow transmit the data from the sensors or does it run the algorithm locally? Does this massively increase the price of the saw? Finally, how would you prevent it from learning about jostling during shipping? Does it just wait for power to start, and then stay on for some amount of time after the trigger is let go?
      Sorry, it's a lot of questions. But again this is a really neat example of how ML can be applied to devices we've had for decades. Cool stuff!

  • Seth Barby
    Seth Barby 5 hours ago

    You two are about to be loaded! Lol

  • Robert Schuster
    Robert Schuster 12 hours ago

    Has nobody ever thought of putting a riving blade on a hand saw?

  • Glenn Mead
    Glenn Mead 15 hours ago

    Confused, where's the spring safety guard?

  • Vern Black
    Vern Black Day ago

    Most professional carpenters use the Makita brand and there is also the problem with the guard sticking and then you set the saw down it try’s to “run” across your foot,yeah it’s definitely a an eye opener

  • Quazie Wabbit
    Quazie Wabbit 3 days ago

    This is serious stuff, folks. Back in the day, I watched a 19-year-old kid, who was “bucking“ two by fours by standing on the end and holding the other end with his left hand while using his Skil saw in his right hand. The saw bucked back and rode up over his inner thigh cutting both his femur and his femoral artery. Long story short, we got him to the hospital before he bled to death.

    GONE LONG 3 days ago

    In All of my years using hand tools Never ever once have I had Circ. Saw kick back on me. That usually happens when someone is exerting to much forward pressure, rather than gliding the saw with finesse. If anyone does experience Circ. Saw kickback they dont need a patent, they need several hand tools familurization and safety classes.
    Even mildly skilled saw users know instinctively when they feel something wrong, to either back the saw up, or release the power trigger which then applies the blade brake.

  • John Aguilera
    John Aguilera 4 days ago

    It’s called hold the saw like a man !!!!!!

  • Nicolai Syvertsen
    Nicolai Syvertsen 4 days ago +1

    The day I have to calibrate the gyro before cutting some wood...

  • Joshua Nelson
    Joshua Nelson 4 days ago +2

    I cut marble and granite with my saw, and I get that kick back 20 times a day..... I hold it tight to my chest so my whole body moves with it Lol...😐 I would like this to be real!

  • Andrew K
    Andrew K 5 days ago +4

    Not pinning your blade guard wide open would go a long way toward safety ;) ;)

  • Ken M
    Ken M 5 days ago

    The biggest problem with safety devices like these is they usually hinder regular usage so are disabled or they will usually not last as long as the tool itself.
    Users need to learn how to safely operate their tools rather than to rely on the device to save them.
    This problem is easily solved by just keeping a firm grip on the tool incase it does kickback, these saws dont have enough power to actually kick out of a firm grip and are only dangerous if you dont expect it.
    Dont get me wrong though, certain tools are better with safety devices like a table saw which can kickback without human error and cannot be stopped.

  • Gary Foster
    Gary Foster 5 days ago

    This test does not make allowance for usage beyond horizontal which makes it useless.

    • Ken M
      Ken M 5 days ago

      Device could easily be programmed to work in other orientations

  • Gary Foster
    Gary Foster 5 days ago +3

    There is no substitute for proper technique. As someone who has operated a circular saw for 50+ years, I have never had a kickback that lasted more than an inch or so. It has only happened over those years when I was extending my arm too far and lost full vertical control so the conditions would allow it. No pro would use your invention. It would actually hinder it's full use. If you hold the saw properly it can't go far. Nor is it difficult to release the trigger in a timely manner. Kickback is only a problem for seriously inexperienced users who probably should not even be using a circular saw.

    • davide bortolami
      davide bortolami 2 days ago

      Ever experienced user has been inexperienced at some point, and thus a potential customer

  • Trav Clement
    Trav Clement 6 days ago

    How about kick back on a chainsaw?

  • Dave and Faith Haverkamp

    I just shared this with a Milwaukee sales rep related to me.

  • superhoov
    superhoov 6 days ago

    I nicked my knee with a chainsaw a few weeks ago, and I mean barely touched it, more of a graze, and had to get 8 stitches. This technology needs to be in all power tools as soon as possible

  • TwistedDDT Gaming
    TwistedDDT Gaming 6 days ago

    can i asked why you dont have a guard , on that saw , that is the safety for the saw

  • steve culley
    steve culley 6 days ago

    that 1st view of that kickback sent my testicles into my armpits.

  • Adrian Valdez
    Adrian Valdez 7 days ago

    Reaction time is worse when you're high somebody I know cut their thumb off

  • Ian9toes
    Ian9toes 7 days ago

    No one gets kickback they can’t handle.
    -20 years in construction

  • 888HUSKERS
    888HUSKERS 8 days ago

    Did you guys do this with a chainsaw yet?

  • Swift
    Swift 8 days ago +1

    That is what a riving knife is for... to stop the timber gripping the blade. They normally also have a spring loaded guard that would cover the blade as it lifts

  • Kevin Button
    Kevin Button 9 days ago

    I mean if you actually stand right and hold it right...the kick back will never happen

  • Lynn
    Lynn 9 days ago

    This is awesome! Why has this not existed before??

  • Roberto Jorge
    Roberto Jorge 11 days ago

    A microswitch in the flat base would do the same at 50 c cost.. I have a pattent on this...

    • acebasespace
      acebasespace 11 days ago

      you mean like if the switch is touching the wood its good and as soon as circuit is broken (lifted sled) the switch is cut off? smart.

  • john doe
    john doe 12 days ago

    pack it and sell it boyyyyyyyyyyyyyyyyy

  • jthrasher47
    jthrasher47 12 days ago +2

    Isn't that why there is a guard on it? The guard is spring loaded and automatically closes so it cannot cut you.. nonetheless it's a very good idea you guys have

  • Daniel Ruiz
    Daniel Ruiz 14 days ago

    He use python for machine learning?

  • James4wd
    James4wd 15 days ago +2

    I've never had a kickback on a circular saw and I've been using saws for years. If your holding it firmly and your strong the blade will just stop when it gets bound up.

    • TwistedDDT Gaming
      TwistedDDT Gaming 6 days ago +1

      thank you , for addressing the fact that if you dont know how to use a power tool dont touch , i too , have never had a saw kick back to the point i would get hurt ,

  • Calvin Robinson
    Calvin Robinson 19 days ago

    1700 people love danger.

  • Brandon Schilling
    Brandon Schilling 20 days ago

    Have you reached out to SawStop? This seems like a perfect fit for them.
    Now figure out how to make routers, planers and jointers safer!

  • TheChunky2010
    TheChunky2010 20 days ago

    Do you not have blade guards on power tools in 'merica?

  • billy19461
    billy19461 20 days ago

    The smart guy is a jock too. Some jocks are smart. Would love to have this on my saw!

  • Keroy
    Keroy 22 days ago


  • Hans Dampfer
    Hans Dampfer 22 days ago +4

    My 30 years old Elu solves that problem mechanicaly. Behind the sawblade is a metal, formed like a sickle/crescent, which is appox. is as thick as the sawblade. In the late 80th of the last century Black&Decker took over Elu, which now is Stanley Black & Decker Corporation. So I think in the US you can also get save circular saws with less electronic.
    I'm to poor to buy cheap tools ;-)

  • אור סוויסה
    אור סוויסה 22 days ago +1

    Why don't just change the direction of the spin to go away from you?

    • Mr. Little
      Mr. Little 19 days ago

      No prob, happy to help!
      The saw blade digging into the woods is what cuts through it, so it needs something on the other side of the wood to hold it and provide something for the saw teeth to push against. Hence the teeth spinning away from your body and up into the front of the saw.
      In the other direction, down from the front of the saw and into the wood, there isn't enough support under the wood for the saw to cut properly and keep the workpiece from moving and bouncing around.
      I hope that explanation makes sense. :)

    • אור סוויסה
      אור סוויסה 20 days ago

      @Mr. Little first of all thanks :) second why?

    • Mr. Little
      Mr. Little 20 days ago

      Then it doesn't cut as well. Less clean and greater chance of vibration.

  • Mike Friend
    Mike Friend 22 days ago

    There’s enough blood on the ceiling at 8:19 to suggest some humans were harmed perfecting this! Haha

  • Jordan Ezell
    Jordan Ezell 23 days ago

    Can you make Da Vinci’s diving suit.

  • Mark Rutte
    Mark Rutte 26 days ago

    what about a riving knife?

  • John Doe
    John Doe 27 days ago

    Many saws have electric brakes and anti-kickback features.

  • Isaac Lewan
    Isaac Lewan 27 days ago

    It's a good idea but it seems like it might cause more problems when making certain cuts. I guess I tend to use circular saws for more than just easy, straight cuts..

  • JopesTV
    JopesTV 27 days ago +1

    2:35 - "It's headed up to your gonadular region." LMFAO

  • Lil' Koolaid
    Lil' Koolaid 27 days ago

    8:00 looks like there's blood all over the ceiling lol

  • Randomodbuild
    Randomodbuild 27 days ago +1

    Make an AI kitchen knife for Rich Rebuilds

  • 45shfifty
    45shfifty 29 days ago

    @milwaukeetools I would give up an extra Grant to see this on a saw.

  • Weston Pullen
    Weston Pullen 29 days ago

    I took a skill saw right in the groin, about 50 stitches when it kicked back. Very scary. Don't stand right behind it.

  • Juan Escobar
    Juan Escobar Month ago

    There is a thing called a blade guard on almost all circular saws that opens and closes over the blade. If there is a kick back the guard closes so you can't cut yourself. Super simple, effective, and cheap.

  • Magic Smoke FPV
    Magic Smoke FPV Month ago

    Rocket saw!

  • Hufla
    Hufla Month ago

    I used to cut aluminum with saws all the time and kickback is actually scary. completely destroys the metal your cutting and sometimes breaks the teeth of the blade

  • Richard Hall
    Richard Hall Month ago

    OK, Both of you guys get off my job right now-drop your tool belts and get OFF MY JOBSITE for ONE HOUR- I’m docking your pay. Why? Where were you at the 7:00am Safety Meeting? NOBODY IS ALLOWED TO CHOCK OPEN YOUR SAW GUARD! EVER.For any reason. OK, after an hour outside the fence, then come back to work. And tomorrow morning you guys better bring coffee and donuts for everyone on the crew for being late. Thems the rules boys.

  • Richard Hall
    Richard Hall Month ago

    In about 30 years of work out in the field,starting as a laborer, then about 25 plus years as a carpenter, working on every type of job-new home building, underground (water catchment basins), large commercial projects, commercial T.I., and finally residential remodeling, this saw kickback-especially with a little old sidewinder(I use mine every day) has never, NEVER EVER happened to me. Thank you very much. Maybe it’s because I always have a really good two handed hold on the little old thing. Heck I don’t know Justin. Go on with your video son, I like what you do.

  • Frugal Fruginni
    Frugal Fruginni Month ago

    I'm really confused with this. I don't work with wood at all, but why not just turn the saw around? That way the blade will pull away from you instead of try to come back towards you?

  • Micro
    Micro Month ago

    this needs to be done for chainsaws as well as they are a lot more dangerous

  • Doomsday Tuther™
    Doomsday Tuther™ Month ago

    omg I can't believe how primitive and far behind you guys are. for a start there alternative ways to cut wood fast without all those nerdy sensors.
    Plus you are using the wrong tool for the job you are doing.

  • John Doogan
    John Doogan Month ago

    Hi, this technology will definitely save lives, I speak as someone who lost his father to such an accident over 30 years ago resulting from the saw cutting his femoral artery. It takes just nine seconds to lose a fatal amount of blood from there. Please keep up the good work and help make these changes throughout the industry with standards of conformity. PS, I never thought that one day I would be writing this and I thank you all for reading this, J D.

  • Joel
    Joel Month ago

    This is amazing! And I would love to see it in chainsaws as well.

  • Delivery McGee
    Delivery McGee Month ago

    "Wait until you see the chainsaw version." Indeed, though the inertial anti-kickback brakes they already have seem to work well enough. Too bad you can't really implement it to table saws (I guess you could, put all the sensors in the psuh block and have it wirelessly talk to the computer ... )

  • haddoxboi
    haddoxboi Month ago

    Why dont you just reverse direction to prevent push/kick back and have the blade pull the saw forward like a wheel. Since the saw blade is spinning backwards or reverse in a car. But if is spun the other way forwards or like drive in a car it would pull the saw forward.

  • Drives The Car
    Drives The Car Month ago

    Very cool!
    Next explain how the table saw stops when you stick a hot dog in it!

  • Adonis Gotflocka
    Adonis Gotflocka Month ago

    Put that in a grinder have you seen grinder accidents

  • Kerry Banks
    Kerry Banks Month ago

    The new phrase that I will continually find a reason to use for the rest of my life "gonadular region". Thank you for truly making me "SmarterEveryDay"

  • Elliot Bywater
    Elliot Bywater Month ago

    or you could just learn how to cut properly

  • PussyPounder420
    PussyPounder420 Month ago

    Another good safety feature would be a multi-stage trigger where you have to pull it a little bit for the saw to cut but if it were to kick back and you were to tense up and press the trigger more it'd shut off the saw

  • MB3Drift
    MB3Drift Month ago

    That’s a game changer! I want it on my angle grinder, and on my dremel too, to keep it from flying away when I put to much pressure. I already made my knees, hands et crotch sweat because of that^^

  • Troll 1122
    Troll 1122 Month ago

    You could make a lot of Money by selling this

  • Marcus Russell
    Marcus Russell Month ago +1

    Such a great idea. I had a large chain saw bind on me and flip me off a ladder. I was using it correctly so that as the limb cut the gap would open not bind. Apparently there was a knot in the wood. I fell profoundly dislocated my should and after several surgeries I wound up with a failed total shoulder replacement. That was over twenty years ago and with the severed nerves I am disabled RetiredLtCol.

  • Addictive_LiquoriCe

    Neural ne... LOL Germans would be proud and jealous of this amount of over-engineering. Safety is good though. No high fours! haha

  • Jimmy Shot
    Jimmy Shot Month ago

    The fake blood on the ceiling is awesome!

  • Beefy Boy
    Beefy Boy Month ago

    And this is why I use pendular saws

  • chrisJongil
    chrisJongil Month ago

    what would happen if the saw spins the other direction?

  • William Downing
    William Downing Month ago

    Americans: make it more complicated
    Русские: комрад, сделай это задом наперед

  • Pierre Martin
    Pierre Martin Month ago +2

    why not have the blade spin the other way though?

  • Bill McCaffrey
    Bill McCaffrey Month ago

    This is an absolutely fantastic invention! I'm a retired engineer that has been a serious hobby woodworker all of my life. This tech would have made radial-arm saws safe (I had one for years and sold it after it chunked a piece of plywood through my garage door just barely missing me. Great work guys.

  • Manabender
    Manabender Month ago

    "Gonadular region"

  • Javier Morande
    Javier Morande Month ago

    We could all tell it was a dewalt 😂

  • woodrabbit7575
    woodrabbit7575 Month ago

    Lol... high five and not high four :)

  • Parada Wigbert
    Parada Wigbert Month ago

    I hate it when I can't understand such things... I wanna learn tho... I just can't put all information together while understanding mechanical/mathematical words in other language

  • Kim Land
    Kim Land Month ago

    This is nothing to a common handheld chainsaw with kickback.
    IF you accidentally get kickback on a chainsaw, the entire saw can jump over your head.
    I know this is true because an instructor was showing us young guys what 'not to do' once, and he said the kickback (of it flying over his head) was so bad that he said he will never show what not to do, again.
    Your bench saw 'kickback' definitely did not show the full intensity of kickback on the angle of a cutting blade. I found this video to be therefore lacking in its concern. It sometimes cuts the other part of the timber? Who cares, as 'kickback' actually KICKS the chainsaw so far BACK it seems to even defy gravity itself!

  • Genesha Irzan
    Genesha Irzan Month ago

    Just waiting for reasonable price..

  • SaltwaterRook
    SaltwaterRook Month ago

    Love your videos and thin book this is ingenious. However, in all my years using a circular saw, I've never had one get away from me. They aren't powerful enough to be unmanageable unless you're really doing something wrong. Table saws are the things kickback nightmares are made of and Sawstop cornered that market.

  • Brian Skupien
    Brian Skupien Month ago

    Awesome! Great job guys! The only thing I see as a downside is no matter how good of a tool or safety mechanism you build, someone always builds a better idiot. You can’t really market this as foolproof, or 100% guaranteed, because someone will figure out a way to sue Dewalt , Milwaukee, Skill, etc. There’s no substitute for good work practices, paying attention, letting the blade do the work, not your hands, etc. geez. I sound like my grandfather or shop teacher.
    Seriously, highly impressive. We have 3 table saws at work. The safe variety. What they don’t say in the marketing is every finger saved costs $118 for a brake mechanism and replacement of the blade. Less than losing a finger sure. But nails or moisture in wood can trigger it, so some guys bypass the stop feature. But you’ve figured out how to do that without buying perishables!

  • George Walker
    George Walker Month ago

    I have been cutting with circular. Saws for 40 years and never had this problem this is a fix to a non p

  • Cookinitmax
    Cookinitmax Month ago

    Had kick back happen the other day kinda.
    My blade guard didn't close when setting saw down the cut it made in the 2x6 not plywood when setting it down made me think what if that was my knee cap it be gone.

  • Tobias B. Broager
    Tobias B. Broager Month ago

    HI @SmarterEveryDay
    Why is it that when yuo close a refrigerator it becomes very hard to open it again after you've closed it?
    hope you understand!

  • El Guapo
    El Guapo Month ago

    Neal Stephenson is amazing! Still can't stand audible though

  • rendzis
    rendzis Month ago

    You need to hold the device tight...

  • Leland Holton
    Leland Holton Month ago

    I welcome safety but this seems like it could be annoying. Thermal overloads in the first generations of lithium battery tools annoyed me because they would shut off randomly.

  • Blue or Red ?
    Blue or Red ? Month ago

    Great vid guys and good idea WE want chainsaw experiment !!

  • Jsweizston
    Jsweizston Month ago

    Yeah.. been there and can confirm that it is terrifying. This is an awesome simple but well though out idea and I"m surprised it wasn't already a thing. With a patent.. you're golden.

  • Gabriel Divine
    Gabriel Divine Month ago

    1/10th of a second? When I trained martial arts, my best response time was about under 3/10th of a second .. when i watched best martial artist, they had about 2/10 .. imagine ugly lazy beer drinking worker .. when we were compared to normal people, we were faster like 10-70 times .. depends on the person .. s from 2 to 6 seconds you can say ..

  • Luca L
    Luca L Month ago

    As a computer engineer I am not exactly sure if machine learning is neccessary, in many cases as a human you can really easily find certain logics and thresholds by looking at test data. However in more complex cases where you cannot really derive a logic by yourself machine learning can really be an effective way of doing it. But in general it usually it is better to come up with your own logic, since machine learning has its own set of quirks. Especially for safety applications it is preferably since you can never really know whiche logic was learned by the machine. Btw a good training of e.g. given a neural network will be really costly too.
    E.g. if you use a machine learning algorithm for this and you only record kickbacks at 0 degree cutting it could not at all work at 45 degree cutting. Or if you cutting on a non even surface it could either behave radically or not at all. Of course those things can happen also with a selfmade logic however you at least can deduct where the error in your logic was and how to improve that. You mostly cannot deduct the origin of the problem with a trained algorithm, you might be able to improve it by adding the problematic scenario to your training data, but still you cannot know if this will fix this problem for all kinds of angles, materials and blades.
    Taking this all together it seems to me that a machine learning algorithm will bring more problems with it than it solves for this particular (relatively simple) case. I am also pretty sure, that detecting a harsh acceleration backwards plus some other minor factors like the saws body rotation could be pretty good in recognizing a real kickback and even differentiate it from man made shaking. But even if the logic could not differentiate kickbacks and shaking, would it be a problem if someone is prevented from running around with a running saw and shaking it? You even might get simular or slightly better results via ML but it would be a bigger hassle and you just cannot be sure about that, so the classic approach would definitely win for me. I mean in the end you obviously have to test this, but I am pretty sure on this one.

  • Luca L
    Luca L Month ago

    I was really confused why this is even a problem, since the blade of my saw turns the other way around so if it would go wild it would travel away from you. However after some research I found out that most (not all) circular saws spin the blade in the direction shown in the video. Btw I am from Germany so I am not sure if saws as mine are existing in the US too.

  • TJamas
    TJamas Month ago +17

    "we're cutting plywood here"
    I laughed hard!

    • rustusandroid
      rustusandroid 27 days ago +1

      I liked the "High Five instead of High Four"... too funny.

  • Zaky-Bear
    Zaky-Bear Month ago

    It's always a great thing when people make safety technology because they want it to be used by EVERYONE and not just because they have an idea that can make them rich.

  • Casey Arrandale
    Casey Arrandale Month ago

    that usually only happens when the blade is Tightened too much if you Tighten the blade to the right spec the blade will spin if it gets caught

    • Casey Arrandale
      Casey Arrandale Month ago

      @SaltwaterRook um yes they are reverse threaded so the bolt doesn't back out during use but if you over Tighten it will cause kick back my dad has been building house's for 40 years I've been using a skill saw since I was 5

    • SaltwaterRook
      SaltwaterRook Month ago

      Uhm no. The arbor nuts are reverse threaded. They tighten during use.

  • Ryan Rose
    Ryan Rose Month ago


  • Matthew Groza
    Matthew Groza Month ago

    Whenever I rip plywood with a circular saw, I do it on the ground with the plywood placed on top of hard foam. Never had a problem.

  • Tom O'Donnell
    Tom O'Donnell Month ago +2

    how about chainsaw kickbacks ? use a manikin, almost 1/2 mithbuster gore. great ideas keep it up.

  • Chadd Chevrolet
    Chadd Chevrolet Month ago

    That is the greatest