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New Safety Feature Detects Flesh

nmb3000 writes "SawStop has introduced a new safety feature for dangerous power tools such as table and band saws which, if accurate and reliable, could result in a lot fewer people visiting the emergency room due to deadly accidents. Using the difference in electrical capacitance between various substances, the system can stop a blade rotating at 4000 RPM in less than 5 milliseconds after detecting contact with flesh. It's hard to understand just how effective this is until you see the demonstration videos where a hotdog is used in place of a potential victim's finger. The site also gives a brief explanation of how the system works as well as some high-speed videos showing just how quickly the blade stops rotating. I wonder if this same technology might be used to protect you neighbor's cat from your robotic lawnmower?"

38 of 124 comments (clear)

  1. They can't do this to me by DeadSea · · Score: 5, Funny

    I don't see how this is going to work for me. I use my power tools to prepare my BBQ. I use the saw to split the hot dogs and shape the hamburger patties.

    It is "features" like this that kill the hobbist market for power tools.

  2. Chain Saw Killers Unite! by ericspinder · · Score: 4, Funny
    ...could result in a lot fewer people visiting the emergency room due to deadly accidents.
    wouldn't a visit to the morgue be a more likely visit with a deadly accident? Can't anyone think of the chain saw killers, I mean what are they supposed to do? Most kidding aside, this would be great for chain saws, right now it looks like it's only available for table saws, perhaps the system is quite large.
    --
    The grass is only greener, if you don't take care of your own lawn.
  3. Bond by Tomahawk · · Score: 4, Funny

    "Now, Mr. Bond, since you won't talk, you will loose your..."

    CHUG.

    "...eh? Damn you SawStop"

    T.

    1. Re:Bond by cjpez · · Score: 3, Informative

      lose . One "o." Say it with me: "lose."

  4. New? by xyzzy · · Score: 3, Informative

    If by "new" you mean "3 or 4 years ago"... This has shot around the internet for ever.

  5. Nope, this isn't new by andawyr · · Score: 5, Informative

    Sorry, this type of safety feature has been available for a few years. I have seen it demonstrated, and it is impressive. 3hp cabinet saw meets hotdog. The blade stopped instantly, with only a small nick taken out of the hot dog.

    The unit I saw demonstrated was a one-use unit. Once the brake was used, it had to be replaced. The system had to be professionally installed, which is very inconvienient unless you have an installer in your city. It was also expensive, relative to the tool. However, when compared to your fingers, how expensive is it really?

    Personally, I would never use one of these things. If you use your tools properly, and avoid running 'bad' wood through your tools, you will never have a problem. Avoid distractions, pay attention, and use push sticks.

    1. Re:Nope, this isn't new by rtaylor · · Score: 5, Insightful

      Personally, I would never use one of these things. If you use your tools properly, and avoid running 'bad' wood through your tools, you will never have a problem. Avoid distractions, pay attention, and use push sticks.

      Since normal people will never trigger the device, they will, of course, never need to replace the device either.

      But it sounds like a great system for the one time the dog manages sneak in and it trips you. Or for schools where a kid, every few years, seems to manage to injure themselves.

      --
      Rod Taylor
    2. Re:Nope, this isn't new by andawyr · · Score: 2, Interesting

      Don't you think that for some people, knowning that they have a safety device installed, might be a bit more careless?

      If you have a safety net, you may be more prone to need it.

      I can certainly see a requirement for such a safety device in school workshops, but as I said before, there is no substitute for proper education.

    3. Re:Nope, this isn't new by andawyr · · Score: 2, Insightful

      I've been using powertools of all shapes and sizes for close to 25 years, and I've never had an accident, nor I have ever come close to injuring myself.

      Why? Because I know how to use my tools, I work in a safe environment, and I make sure my tools are in good working condition. If you don't know what you're doing, or are careless, or, or or, then sure, purchase a safety device to protect yourself. What I'm saying is that if you DO know what you're doing, you won't need it.

      For places like schools and public wood shops, sure, the device could be installed. In those situation you're working with unknown quantities - people are just learning, or are too immature to really understand what they're dealing with.

      Safety devices are great, but they are no substitute for brains. We can't pad every sharp corner in the world either...

    4. Re:Nope, this isn't new by gl4ss · · Score: 3, Insightful

      uhh.. but by default you won't know if you know or don't know what you're doing. or if the cat got in and jumps on your back, or whatever unforeseeable.

      accidents aren't planned, they just 'happen', usually because something that you didn't expect happens. then it's quite good to have a failsafe.

      besides, it looks like it still would hurt enough to not joke with the thing.

      there's plenty of people in the world who have operated some devices for 20-30 years and then had an accident, why would you be different from them? People that think that they know what they're doing have accidents all the time.

      --
      world was created 5 seconds before this post as it is.
    5. Re:Nope, this isn't new by Hungus · · Score: 3, Insightful

      The cars are inherently safer. What you should have said is the DRIVERS of cars with antilock brakes are inherently more dangerous.

      --
      Bad Panda! No Bamboo for you! In matters of importance ACs will not be responded to. Want to say something critical,OK
  6. How does the brake by PhysicsGenius · · Score: 3, Interesting
    "absorb the energy" that quickly? The only way I can think of that wouldn't involve having to change brakepads (or install a new device) every time is magnetic braking. And that's going to cause a big EMP which, if it doesn't fry the tool's electronics, will at least any nearby pacemakers to go haywire.

    I can just see it now: A retired carpenter is doing a little sawing, accidentally puts his finger in the way but SawStop saves it....at the cost of his life.

    1. Re:How does the brake by HyPeR_aCtIvE · · Score: 4, Informative

      That's simple ... you DO have to install a new device every time, at fairly high cost. One of the reasons most folks don't like this device.

      Of course, they also don't like it because the inventor has been trying to get legal action to FORCE all manufacturers to license and install his device, because otherwise they are 'being negligent'.

    2. Re:How does the brake by Electrum · · Score: 4, Insightful

      That's simple ... you DO have to install a new device every time, at fairly high cost. One of the reasons most folks don't like this device.

      That's silly. The cost of losing a finger or an arm is greater.

  7. Taking Bets... by Dozix007 · · Score: 3, Funny

    Who will be the first to "Hack" the saw so you can vary the delay time. Survival of the Fittest may still succeed !

  8. So what happens if... by lunarscape · · Score: 5, Funny
    So what happens if your arm gets pinned under a fallen beam in a fiery explosion and your only hope of escape is to use the nearby power saw to amputate your own limb? This happens:

    "Yes! I am saved by this power saw that is still miraculously working despite the fiery explosion!"

    ::Turns on power saw and moves it toward arm::

    ::Power saw clicks off::

    "NOOOOOOOOOOOOOOOOOOOOO!!! Damn you science!!!"

  9. Re:Why a Hot Dog? by Tomahawk · · Score: 4, Funny

    Honestly, would you like to donate a finger to nick for a video?

    Imagine it - 'Ok, cut.', and everyone fall around laughing.

    'BandAid him, take 2'

    'no no no - another bandaid - take 3'.

    I think the hot dog serves the purpose.

    T.

  10. The really amazing thing is... by wanerious · · Score: 2, Funny

    I suppose this is finally evidence that hot dogs are made out of the same kind of stuff as flesh.

  11. Re:5 ms eh? by Tomahawk · · Score: 4, Informative

    (4000 / 60) = 66.66666 rps

    50 teeth => 50x66.6666 = 3333.3333 tps (teeth/sec)

    5 milliseconds is 5/1000 seconds, so...

    3333.33333 / 1000 = 3.33333
    *5 = 16.6666

    So, that's 16-17 cuts, max. The blade is slowing down, and retracting, in that 5ms, so it would be even less than that.

    T.

  12. The joys of severed limbs by rit · · Score: 4, Interesting

    I thought people might appreciate the humour of this story...

    Several years ago, I went through training as an EMT in the great state of Pennsylvania. We were fortunate to have our main training classes held in a Vocational Technology college - which meant we had all sorts of great rooms and setups for running scenarios.

    As part of our final exam, we were dispatched to the woodshop room - a room full of hundreds of bandsaws, etc. - for a report of a possible bandsaw accident.

    Now there are two things we were trained to keep in mind with possible amputations:
    1) Find the limb immediately and pack it in ice - it is very likely it can be saved and reattached.
    2) The patient/victim rarely realises, due to the shock of things, that they've actually lost the limb. So for godsake, don't let them notice.

    We arrive on 'scene' in this gigantic shop room, which had row upon row of bandsaw, and the actor is sitting there, fully done up complete with fake severed hand gushing blood, which she has a towel pressed against. She informs us that she was working on the bandsaw and cut herself, and she thinks it's pretty deep. My partner carefully approaches, lifts the towel - and it's quite clear [thanks to the instructors insistence on proper special effects to simulate the injury] that the hand is completely severed.

    Taking the initiative on action point #1, I scan the nearest bandsaws for any sign of the severed limb, and see nothing. My brain takes control before I can think, insistent upon finding this limb, and of course states to the patient "Ma'am, Where is the rest of your hand?"

    And as if on cue, the actor flips out and starts wailing and shrieking and flailing, and then descends into shock...

    And all I wanted to do was help her find her hand!

    [We ended up passing the exam, with a minor downcheck for not being more delicate about the severed limb with the patient - the hand was in the very back of the room. Apparently none of the other groups even thought to find the limb, and took the patient to the hospital immediately].

    1. Re:The joys of severed limbs by bradkittenbrink · · Score: 5, Funny

      [We ended up passing the exam, with a minor downcheck for not being more delicate about the severed limb with the patient - the hand was in the very back of the room. Apparently none of the other groups even thought to find the limb, and took the patient to the hospital immediately].

      How many of the other groups passed? Should I move out of Pennsylvania?

  13. Automatic hunter? by mst · · Score: 2, Interesting

    > I wonder if this same technology might be used to protect you neighbor's cat from your robotic lawnmower?

    I wonder if this same technology might be used to create an automatic, mechanical, cat replacement that uses the meat detector to find mice. (But then again, how would you keep it from eating your neighbor's kitten too?... :-)

  14. victimless ? by DrSkwid · · Score: 3, Funny

    I know Apu might sell soy-dogs but making one from cows is not a victimless crime.

    Time to send some of these saws to the abattoir.

    Now, if it's a victimless breakfast you want ......

    bring it on

    --
    There are places where the networks are not touching,and there are places where they are-Boeing's Lori Gunter
  15. Having removed part of a finger myself... by clintp · · Score: 4, Informative

    March 2003 I took a good chunk out of my left index finger on the table saw. Ouch.

    And I'm normally a very, very careful person on the saw. But between a little kickback, hands in the wrong place, an odd shaped piece I wound up with an avulsion laceration (ripped the skin off the fleshy part of my fingertip about 1/8" wide and bone deep). Quick trip to the ER. Nothing really to stitch up, the doctor left it open but dressed and packed for a couple of weeks. The skin grew back, and I've got a rather odd fingerprint there now.

    I'd trade what happened to my finger for the damage done to the hot dog any day.

    This needs to be expanded to routers and hand tools. Kickback from circular saws is very frightening.

    --
    Get off my lawn.
    1. Re:Having removed part of a finger myself... by Carbonite · · Score: 4, Funny

      This needs to be expanded to routers and hand tools.

      No kidding! My friggin Linksys took off three fingers.

      --
      ich muß mehr Kuhglocke haben
    2. Re:Having removed part of a finger myself... by himself · · Score: 4, Funny

      clintp wrote:
      >
      > The skin grew back, and I've got a rather odd fingerprint there now.
      >
      I took off a "plate" of flesh from the end of my left thumb while slicing potatoes two Thanksgivings ago. Not only do I now have a puckered blank in the center of my thumbprint, but some touch-sensitive controls (like my iPod's!) ignore the thumb.
      On a more positive note, I am no longer asked to help prepare food when visiting my in-laws' house.

  16. Catsense by WWWAvenger · · Score: 3, Funny
    "I wonder if this same technology might be used to protect you neighbor's cat from your robotic lawnmower?"

    I've developed a heat-sensing technology for robotic lawnmowers in this vein... but it isn't meant to PROTECT the neighbor's cat.

  17. Re:False Positives by chriso11 · · Score: 2, Informative

    The FAQ on the website says that green wood and wet wood will not trip the stop.

    Of course, I don't know what other circumstances could produce a false negative - perhaps touching the side of the blade while spinning, but not the teeth?

    --
    No, I don't trust in god. He'll have to pay up front, like everybody else.
  18. Re:False Positives by confused+one · · Score: 2, Informative

    They said in the FAQ that wet wood would not cause it to misfire.

  19. Left-handed people by acceber · · Score: 4, Interesting
    Considering that most, if not all machinery is catered for right-handed people, I can see how SawStop would be extremely appealing to left-handed people who have to work their brains around tools that would be potentially dangerous if used in a left-handed fashion.
    Research shows that left-handers are 51% more likely than right handers to suffer accidental injury using tools machinery or other implements

    If you're right-handed, imagine having to use all your machinery and tools the "wrong" way (ie left-handed). Even though there are more left-handed people today, the fact stands that the majority of the world's population is right-handed so left-handed products will become nothing more than the niche market it is today.

  20. Great news ... by polyp2000 · · Score: 2, Funny

    For a moment their I thought there was a new browser feature that bypasses all those annoying flash adverts... Unfortunately I read the title wrong.

    "New Safety Feature Detects Flash"

    Nick

    --
    Electronic Music Made Using Linux http://soundcloud.com/polyp
  21. Seriously... by hlh_nospam · · Score: 4, Insightful

    A bandsaw is commonly used to cut meat in butcher shops. I'm guessing that this device would not work on that application.

    Also, gotta wonder if this sort of thing might actually *increase* the number of injuries from power cutting equipment -- by reducing the level of respect for the destruction power of the equipment. Sorta like some of the safety features of automobiles has led to some folks driving more agressively...

  22. Re:5 ms eh? by BillyBlaze · · Score: 2, Informative

    The site has several high speed videos, like this one, and from the looks of it, only one or two teeth hit the hot dog.

  23. In other news... by msouth · · Score: 2, Funny

    ...John Wayne Bobbit had all of his kitchen knives replaced with electric knives sporting the new technology.

    --
    Liberty uber alles.
  24. Re:False Positives by jerde · · Score: 2, Informative

    Man, if you were working on something and your wood got a little too wet or something, and this thing went off incorrectly, it would be both problematic and expensive. A false negative would be pretty bad too.

    The features page (which has javascript rollover junk that Safari won't Grok) lists a "Metal Bypass" for cutting metalic or metal-clad stuff, that WOULD conduct enough to trigger the device.

    As far as false-positive expense: I'm guessing if the total system cost is only $50-$150, then the replacement breaking cartridge couldn't be THAT expensive.

    False negative would be unfortunate... I wonder how they protect themselves legally? Freak accidents could still happen, and if their magic "safety system" didn't prevent it, would people want to sue them?

    - Peter

    --
    INsigNIFICANT
  25. Re:False Positives by clarkcox3 · · Score: 2, Informative
    --
    There are no tiger attacks in my area and it's all because this rock I'm holding keeps the tigers away.
  26. Too bad more safety professionals don't read /. by Bahumat · · Score: 5, Insightful

    I work in the Loss Control industry, which is a fancy way of saying I try to make jobs safer for people so that A) you still have your limbs at the end of the day, and B) your employer doesn't have to pay through the nose for injuries/casualties.

    I showed the videos to the Director of the company and immediately it's been making it's rounds through the office. This is exciting technology, this is *important* technology. Ask the thousands of labourers, carpenters, shop workers, around north america who've lost digits to cutting accidents what they think of this technology. No, you won't hear a goddamn negative thing.

    Some people have complained about the inventor of the technology trying to make the device mandatory on cutting tools. Is this self-serving for him? Hell yes. Is he still in the right? Undoubtedly. Hard hats, steel toe boots, rebar covers, flagmen, confined space entry, are all areas of industry that are strongly regulated by governments, and made mandatory by law. This should, without a doubt, join it.

    One significant aspect of the technology that needs to be addressed however, and raised by a fellow /.'er, is that the cartridge must be re-useable. Not infinitely, but it should be able to hold at least 6 good stops to itself before needing a cartridge change. (By law, and good safety policy, such systems should be regularly tested.)

    I look forward to this technology becoming industry standard. The man who invented it is going to be filthy, stinking rich, and definetly deserves to be. That's what innovation leads to; success.

    And for the rest of you going on about "You don't need this if you're careful.", I call bullshit. You need a hardhat, you need safety goggles, you need steel-toe boots. *YOU* can be careful, but you can't control all variables around you. That's why they're called 'Accidents' when they happen.

    --
    "To pass through the jungle; silence, courtesy, ferocity, as the occasion demands." -- Kamau, "Proper Passage"
  27. Re:The problem with science... by cmowire · · Score: 2, Funny

    Nope, the problem is that cutting yourself with the blade is only one of the *many* ways you can hurt or kill yourself with power tools.

    I'm mostly thinking about the fun tendancy of a table saw to fling wood at you if you aren't careful.