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Skin Sensing Table Saw 471

killabrew writes "Check out this article from Design News about a new skin sensing table saw technology that is on the verge of becoming a mandatory piece of hardware on every table saw. For years inventor Stephen Gass persevered in the face of legal, corporate and technical foes, he is forcing society to rethink its acceptance of saw blade accidents."
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Skin Sensing Table Saw

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  • Dupe from 30-Jun-04 (Score:2, Informative)

    by Anonymous Coward 0/131241 []

    Which was probably duped again earlier.

    Quick, go steal some +5 comments from that one!
  • "Saw III" (Score:5, Funny)

    by krell ( 896769 ) on Monday August 14, 2006 @10:21AM (#15902413) Journal
    Something tells me the next one will be G rated.
  • by Kranfer ( 620510 ) on Monday August 14, 2006 @10:21AM (#15902415) Homepage Journal
    At first I was very wary of reading the article, thinking how could it possibly sense that? Then I watched the video... very very nifty it barely cut into the hotdog they used as a test. Now, I would think this technology would be VERY welcome in all industries where moving parts like saw blades, robotics etc are used... Why wouldn't they want to embrace safety technology like this?
    • by metasecure ( 946666 ) * on Monday August 14, 2006 @10:23AM (#15902432)
      didn't RTFA, but what if your skin is not made of hotdog ?
    • Why wouldn't they want to embrace safety technology like this?

      The most obvious reason is cost. If a company hasn't been hit by an accident in the past, then if (like a lot of companies) they're purely looking at their bottom line, why would they pay more for this saw than the one they've already got...
      • by UbuntuDupe ( 970646 ) on Monday August 14, 2006 @10:39AM (#15902557) Journal
        That's true, but it's not nearly as malicious as you make it sound. Employers have choices: they can pay to eliminate the hazard, and then have to pay less to get workers to take the less risky job, or they can not eliminate the hazard, and have to pay more to get people to take the more risky job. Economists call this a "compensating differential". It's seen in the difference in pay between regular window washers and high-rise window washers, for example. It can also be negative in jobs that people enjoy doing (i.e., they make less than those of comparable skill and experience because the job is fun, like astronauts).

        There is always going to be some level of safety below which people will say, "forget it, it's not worth it, I'd rather just take the cash than make myself 1 in a million less likely to die". For example, would you take a 20% pay cut to halve your risk of death on the job?
        • Or, option three, outsouce the job completely to a country that wouldn't even consider using a safer saw.

          Although I think your first two are options as well, you forget that not only do employers pay higher cost, if someone does get injured, they pay for the medical expenses related to the injury, likely for the life of the employee.
      • Having worked as RN in a large factory which had Lost Time Injuries approximately every 3 days.... and which could have saved a fortune if modest changes had been made, I have discussed this with management.

        The motivation of the management who makes the decisions is one of control and temper. It really does make sense to make things safer. This factory could have saved about $100,000 a week had it improved safety. They just didn't want to do it. You see a worker was only paid about $50,000 a year and as

        • by Registered Coward v2 ( 447531 ) on Monday August 14, 2006 @10:59AM (#15902737)
          aving worked as RN in a large factory which had Lost Time Injuries approximately every 3 days.... and which could have saved a fortune if modest changes had been made, I have discussed this with management.

          The motivation of the management who makes the decisions is one of control and temper. It really does make sense to make things safer. This factory could have saved about $100,000 a week had it improved safety. They just didn't want to do it. You see a worker was only paid about $50,000 a year and as such these people didn't cost management enough to be worth anything to them.

          I watched the expensive management employees get protected while the workers got nothing. This was a tire factory. They made $1,350,000 a day even with this injury expense. It may be strange to some but actually the workers were too cheap to be worth anything. The loss of a life about every year or so was an acceptable cost to management. So what if you pay off the family with a damage claim of $500,000 or so. Blow it off. These people are worthless in the eyes of management...

          Saving $5,200,000 a year simply didn't enter their mind as worth that much effort. I proposed that we use the medical data to extract which machines should be fixed. I offered to observe the machines and look at what was going on. They had no interest. One major loss to them was hearing losses. The addition of a few minor changes could have nearly silenced the factory. They couldn't care less. Another major loss was loss of hands and fingers and intermittently a person in a machine. Simple design changes in jobs would have improved production and saved lifes. They didn't care because it might "bother" their situation. It was an attitude that the "Free Trade" advocates refuse to recognize. Burried in the true motivations of many rich persons is a hatred of other social classes and a view that they are property not people. This is why they will not embrace safety technology.

          Your numbers don't make sense - $100,00 is about 1% of a weeks take (per your numbers) which is usually enough to get a company take notice; which is why I doubt your numbers. Either they are wrong or the required changes were so expensive as to be unaffordable - so when you say:

          One major loss to them was hearing losses. The addition of a few minor changes could have nearly silenced the factory.

          I have to wonder - silencing an industrial environment is not easy nor cheap - which is why wearing proper hearing protection is generally the best fix (and enforceable as well).

          Then again, your last paragraph shows where you are coming from - I sense you had an agenda that was not well received and probably not realistic nor practical.
        • Yours are good points, but you can go too far.

          When I was working at a storage systems facility owned by a large company, which it later sold to another large company, there was an on-site accident that landed an employee in the hospital.

          Suddenly, we were policed for over-the-top compliance on every perceived OSHA requirement, greatly slowing down our productivity. For example, even though it wasn't policy, we were no longer allowed in the cleanroom without steel-toes shoes, etc.

          Then we finally found out the
    • Why wouldn't they want to embrace safety technology like this?

      Same reason safety is an afterthought in many industries: expense. New technology is always a bit expensive. They need to make this cheap for it to be widely adopted. Otherwise it will only makes its way into the high-end equipment.

      Hopefully they will be able to sell a critical mass quantity to bring the price down and make it available to every tool maker.
    • by M-G ( 44998 ) on Monday August 14, 2006 @10:26AM (#15902457)
      Because safety technology sounds good, but frequently doesn't hold up to heavy use, rough handling, dirt, etc. on the job site. Then the safety device gets in the way of getting work done, and it gets bypassed. And for all of that, you get to pay more for the tool.
      • by shawn(at)fsu ( 447153 ) on Monday August 14, 2006 @10:40AM (#15902567) Homepage
        Then the safety device gets in the way of getting work done, and it gets bypassed
        or it gets by passed because people are lazy and management looks the other way. For example the meat slicer at a restaurant/deli. I heard horror stories from my friends that started part time jobs in HS before me about how dangerous the slicer was they'd show me the cuts and the missing tips of fingers that would end up in tonight's bread pudding. So when I got a job that required me to use the meat slicer I was very careful and I found that if you would just keep your hand on the grip and behind the "shield" you were ok. I never cut myself or came close to it. So my point is even if the safety device is simple and it doesn't get in the way of proper use people will still find ways to hurt themselves in efforts to expedite their tasks.
    • Why wouldn't they want to embrace safety technology like this?

      I would think that it would remove a very painful consequence to carelessness around the machine shop. Unless a saw is defective by design, many of these kinds of accidents are caused by human error. If you rely on a safety mechanism to keep your fingers rather than dilligence and common sense, accidents could increase if bad habits developed by a reliance on these devices are applied to the older machinery in the shop or a faulty safety mechan
    • t barely cut into the hotdog they used as a test.
      But what if I want to use my tablesaw to cut through hotdogs (or body parts...)?
    • Because it will be forced to be implemented in all American manufacturing companies, which will raise prices of American goods even more, and push yet more jobs off-shore where they won't implement these measures.

      Just to make it clear, I'm all for making things safer where theres a way. I think 'fair trade' should include provisions to make products more expensive if they are made in countries that do not have similar safety and workers rights law. Unfortunately we'll likely have to end up giving everythi
    • The article addresses that, but to sum it up - the power tool industry has no financial accountability for table saw accidents. There's a longstanding legal precedent for saw makers not being accountable for table saw accidents, on account of the fact that anyone who would use a saw should be well aware of how dangerous they are and should be taking their own precautions as a result.

      The rather outrageous licensing fees (8%) the guy was wanting for every saw produced with the technology couldn't have helped,
    • I tried to buy one. (Score:5, Interesting)

      by RonTheHurler ( 933160 ) on Monday August 14, 2006 @10:54AM (#15902701)
      I saw this demonstrated once, on the Tonight show, with Johnny Carson (yes, I'm that old and yes, this thing's been around that long!)

      So, when I finally had a reason to go buy a tablesaw for my business, and I saw the horrible cost of insurance, I tried to buy the auto-shut-off table saw. Of course, I searched the web. Then I called the big saw distribution importers and distributors. It took some effort, but I finally got an answer why they were not, and probably would never be available.

      It's not a perfect product. It is still possible to get your fingers cut off, and it is possible to have it "jam" on plain old wood too. When it jams, you have to replace the blade and the whole blade jamming mechanism- it can take most of a day to do that, if you have the parts, and it's expensive. It can cost as much as a whole new table saw each time it goes off.

      All those things are solveable, but I was also told that the insurance companies hate the thing. It sounds counter-intuitive, but you know that a table saw is dangerous. If you believe that it's less dangerous, then you might be more careless too. The car companies had a similar argument against seat belts back in the 1960s.

      There are better solutions in industry. CNC automated machines are used where lots of similar parts need to be made. There are very few, if any, one-off parts in manufacturing environments. So the only real market for this machine is the hobbyist or general contractor and cabinet maker, and the professionals have really good stafety rules anyway (at least the ones where I worked did).

      But, as it stands, nobody has a case if he tries to sue the manufacturer because he cut off his finger. But put an auto-brake on the saw, and every time it fails the manufacturer and insurance company have a dismemberment case to settle.


      Use your table saw today! Get catapult and trebuchet kit plans at []

      • But, as it stands, nobody has a case if he tries to sue the manufacturer because he cut off his finger. But put an auto-brake on the saw, and every time it fails the manufacturer and insurance company have a dismemberment case to settle.

        An well-said, although unfortunate, point.

        It's seemed to me for a while that we need -- if we can't actually accomplish all-over tort reform -- some sort of a "good samaritan" law for corporations as well as individuals.

        There shouldn't be any liability reasons for not putting a safety device like this on your equipment. But the system as it stands doesn't encourage it, for exactly the reasons you mention. Without a safety device, and as long as they're not "expected," when someone takes their finger off, it's just their own damn fault. But with the safety device, they'll be a massive lawsuit whenever it doesn't work perfectly -- even though it might work very well most of the time.

        This reminds me of the situation in many states prior to the introduction of "good samaritan" liability laws. You'd have doctors and off-duty paramedics driving past the scene of an accident and not stopping, because nobody wanted to risk getting sued. It was only after some pretty ridiculous and unfortunate situations, where it became clear that as a society, we shouldn't be encouraging people to leave their fellows bleeding to death in a ditch because of fear of being sued later, that many states have changed the law.

        A company which makes it's products safer than the norm shouldn't be liable for suits when the safety mechanism fails, if the result of the failure is that the product is only as dangerous as the device would normally be expected to be (assuming the manufacturer has not advertised it as being much safer, or that less precautions are necessary).

        Any time you have the law encouraging the creation of more-dangerous products for perceived liability reasons, you have a problem. The goal of the law should be to encourage and reward productive behavior, not discourage and punish it.
        • Great. We will have companies that make cheap "safety" equipment that doesn't work but meets the legal requirement so that they can't be sued. Sounds like a republican dream. Whoopie!
        • It reminds me of the last time I went golfing. Most nerds will realize that metal golf clubs, open spaces and lightning is a really bad combination. Because of this, golf courses are required (at least in my state) to be outfitted with a blaring horn that is supposed to sound when anyone spots lightning. Well, last time I went golfing, we saw lightning off in the distance and ran for the clubhouse. We told them they should sound the horn because a big storm was coming and we saw lightning. His response floo
  • Good product (Score:5, Informative)

    by dave-tx ( 684169 ) * <df19808+slashdot ... m minus math_god> on Monday August 14, 2006 @10:22AM (#15902421)

    Here [] is a writeup of the saw's debut at the International Woodworking Machinery & Furniture Supply Fair (2000). I remember reading this back in 2000 thinking "great idea, but I wonder if it'll ever get adopted". Glad to see it's gaining traction - the table saw is the only piece of equipment in my shop that I'm nervous around.

    Now if they can solve kick-back, I'll be a tablesaw fiend.

    • Re:Good product (Score:3, Informative)

      There was a large table saw comparison review in Fine Woodworking recently. His saw was one of the top rated. It is good that he has built an excellent saw (one that is excellent, even if it didn't have the safety features) that can compete with the best saws in the industry. His was also expensive, but I imagine that having fingers re-attached costs a lot more. The saw blade gets trashed when the safety fires, but again, a saw blade is cheap compared to a trip to the hospital.

      As far as kickback, a s
    • Re:Good product (Score:3, Informative)

      by Anonymous Coward
      They have solved the kickback problem. First, this saw uses a riving knife at the back of the blade. That is, it has a rather sturdy curved blade that stays fixed behind the rotating blade. The riving knife goes up and down with the blade and helps keep the wood from touching the back of the spinning blade, which is the root cause of kickback. Another think you can already do to reduce kickback is to ensure that you fence is exactly parallel to the spinning blade. In the alternative, you can have the b
    • Now if they can solve kick-back...

      Keep your blades sharp and don't allow that cut measure to sit angled on the table, causing blade binding when you use it as a cutting guide.
    • Re:Good product (Score:3, Insightful)

      by jonored ( 862908 )
      In all honesty, you need to be scared around it. Even if you have this system, you still need to be scared of the table saw. Just because the table saw is supposed to notice you and stop doesn't mean that it actually will; what if, say, some fleck of metal gets into the electronics, and shorts the mechanism holding that block back (haven't gotten to the article, but that's how I'd design such a thing - try to fail on the stop side), and when you trip into it moving too quickly it doesn't stop? While you sho
  • by Anonymous Coward on Monday August 14, 2006 @10:22AM (#15902429)
    > For years inventor Stephen Gass persevered in the face of legal,
    > corporate and technical foes, he is forcing society to rethink
    > its acceptance of saw blade accidents."

    Proof of why this technology is needed: the above sentence was horribly, tragically mangled in a comma splicing accident.
  • by suso ( 153703 ) * on Monday August 14, 2006 @10:23AM (#15902439) Homepage Journal
    Bret: "I only got a scratch from the blade, but I broke my foot when the whole table saw flipped over."
  • Whooops... (Score:3, Funny)

    by Mad_Rain ( 674268 ) on Monday August 14, 2006 @10:25AM (#15902450) Journal
    It looks like it couldn't stop the slashdot buzzsaw - it cut straight through their server.
  • by Rob T Firefly ( 844560 ) on Monday August 14, 2006 @10:27AM (#15902464) Homepage Journal
    Gone are the days of charming high school wood-shop teachers who hold up two hands' worth of fingers when counting off their five years' teaching experience. What's next, forcing them to shave their woodsman's beards and stop wearing flannel?
    • One of my tech teachers in high school only had 9 fingers you insensitive clod!

      And scary enough, I'm not kidding (about the fingers)

      • I moved around high schools a lot, and each one had a tech/shop teacher with at least a small bit of a finger missing. I wondered if it was a traditional thing, like in the Yakuza.
      • Umm, I think that was the essence of the OP's joke - the woodshop teacher has too few fingers to count to five on one hand.

    • Even worse, how else are the shop teachers going to keep the lil' barbarians in line if they can't threaten to saw off body parts???
  • by Anonymous Coward on Monday August 14, 2006 @10:27AM (#15902465)
    But what if I'm trying to cut meat on my table saw? I guess I'll be stuck with the band saw and the wood chipper...
    • by JediTrainer ( 314273 ) on Monday August 14, 2006 @11:10AM (#15902821)
      Sigh. That reminds me of the time that my dad and uncle came up with the brilliant idea of cutting frozen salmon on our table saw.

      In the basement.

      The finished basement.

      After all was said and done, walls and ceiling were covered in fine salmon shavings. Gross. Mom was less than thrilled.
      • by maddogsparky ( 202296 ) on Monday August 14, 2006 @12:09PM (#15903346)
        My dad once butchered an animal (beef, I think) and left in the barn to cool. He couldn't get to it for a few days and it froze solid (Minnesota winter). He needed to cut it into smaller chunks to be able to carry it inside for cutting up. So he thinks: chainsaw!

        Much of it had to be thrown out due to all the bone chips. :-(
  • I cant read TFA, probably slashdotted already...

    Does it stop spinning once it tastes human blood?

    Does it stop spinning once it encounters less resistance?

    And what about slasher films? Are Jason, Freddie et al, going to have to look for vintage saws for their work?

    I dont get it, please somebody explain
    • Flesh has certain properties of electrical conductivity and capacitance different from wood. When the metal saw touches flesh, it senses the change in conductivity and sends a stop signal.

    • Well our bodies give off an electical charge (which is very close to a hotdog) and the blade being metal. So when it hits our skin a low level electic charge is shot across the blade into a chip that determins if it is the same electical change as a human hand. If it is then it fires a stopping pin that breaks the saw very fast, and allowing it to only scratch the finger, mind you it will be a deep scratch, and will hurt like hell but it will heal in time and with a banage you can continue with work that d
  • by Anonymous Coward on Monday August 14, 2006 @10:31AM (#15902485)
    As someone who was involved in evaluating this technology for a major US manufacturer of power tools, there are a number of issues which prevented early adoption. First and foremost was the inventor's demands for unreasonable royalties (including a percentage of the gross sales of table saws from preceding years!). I heard the director of the power tools group say that if the royalty had been reduced by 50%, it would have been a no-brainer. As it was, the proposed royalty structure was just unsupportable for a saw that sold for $500.

    The second issue was that the product had great difficulty distinguishing the change in capacitance due to human flesh from that due to very wet lumber. This has undoubtedly been improved over the past few years, but people would have been somewhat unhappy to have false triggers that required them to a) replace the safety cartridge and b) their saw blade, which is consumed when the system triggers. Not to mention having the bejeesus scared out them when the system fires in error.

    To talk about the inventor persevering in the face of corporate pressure is silly. This isn't a David vs. Goliath story. The inventor was a patent attorney that tried to bludgeon power tool companies with a 250+ page patent, and he could have sold his concept on day one if he hadn't been quite as greedy. There was no shortage of companies looking for competitive advantage in the power tool industry, which has been pretty stagnant of late.

    • by radtea ( 464814 ) on Monday August 14, 2006 @11:37AM (#15903066)
      This isn't a David vs. Goliath story.

      Yeah, this is more of a Beavis vs Butthead story, and is fairly typical of the way new technology is introduced.

      Part 1: Clever, arrogant guy gets brilliant idea and develops it to the point where he is convinced it'll change the world. That's the science and tech part. Now it's all done, ok? There is no more science or technology in this story after this point. Only politics and monkey psychology.

      Part 2: Clever, arrogant guy tries to change the course of history in a year or so, and cash in hugely in the process, by selling his idea or some instantiation thereof to established industry players. He pisses off everyone in the industry in the processes, which is easy to do because they are at least as arrogant and far less clever than he is.

      Part 3: A messy, improbably stupid battle of wills ensues as the industry tries to do an end-run around the inventor and the inventor tries to harrass the industry in to buying his tech. This can go on for as long as decades, but if anyone "gave in" it would be a matter of "losing face", and "face" is extremely important to monkeys. If a monkey loses face, he will be demoted in the hierarchy of the troop, and that has all kinds of costs associated with it, including potential mating opportunities. So evolution has pretty much tuned monkeys up to act like arrogant assholes in these situations, because arrogant assholes are what female monkeys are most interested in, because arrogant assholes can command a greater fraction of the troop's resources.

      Epilogue: Many years later, the technology is widely adopted and all concerned are hailed for their forward-looking stance and innovative thinking. Companies that fought the tech tooth and nail now tout themselves as early adopters (which they may well be, relative to other companies.) The original inventor, ignoring all the progress that has been made in making his original prototype a practical, manufacturable device, is hailed as a great innovator.

      The amazing thing about modern social democratic market societies is that we are actually the most efficient innovators in history, and not by a small fraction.

  • by Pontiac ( 135778 ) on Monday August 14, 2006 @10:31AM (#15902488) Homepage
    This guy has been trying to force his invertion on us for years..

    After the saw manufactures refused to pay his unreasonable licensing free (3-8% of the saw sale price)for his patented tchnology he moved on to lobbying for a law to make it mandetory (and still pay his licensing fee)

    I have to agree the idea is cool but I don't like having it forced down my throat.
    He did go on to start his own saw company and makes one of the best saws on the market...
    • Re:Link to web site (Score:3, Informative)

      by Pontiac ( 135778 )
      I forgot the link to the SawStop site []
    • Not only that, but if for some reason the device acidentally trips, you're out a whole lot of cash replacing the blade, brake shoe and no telling what else. For someone who can afford a $2000 cabinet saw, this may not be that large of an expense, but for the average person doing this as a hobby, we tend to pinch every penny. Heck, I've been doing this as a hobby going on 10 years, and I can't justify to SWMBO why I need a dado stack for my saw. If I had to buy a new saw with this technology, I'd have to giv
  • Yes! (Score:3, Funny)

    by Geminii ( 954348 ) on Monday August 14, 2006 @10:34AM (#15902513)
    Finally, I can saw naked!
  • No big deal. (Score:5, Insightful)

    by WhatAmIDoingHere ( 742870 ) * <> on Monday August 14, 2006 @10:34AM (#15902517) Homepage
    Professional carpenters will just find a way of disabling this, like the blade guards on circular saws and the 'safety' on nailguns.

    Honestly, you're not a carpenter unless you have a few battle scars to show off.
    • Re:No big deal. (Score:3, Informative)

      by microcars ( 708223 )
      "Professional carpenters will just find a way of disabling this, like the blade guards on circular saws and the 'safety' on nailguns."

      All they have to do is turn the key on the side of the unit that "disables" the safety feature.
      It comes standard on the saw.

      Some friends of mine own a Scene Shop that makes sets for Stage Productions and they bought a pair of these a couple of years ago.

      Being a Scene Shop, they don't just use the saws to cut wood, they also cut Acrylic and Aluminum.

      They HAVE to disa

  • but alas the technology wasn't around in my 9th grade shop class.
  • Here is the link from NPR Story in 2004 []

    The interesting thing is that the power tool industry refused the technology because it was too safe. They were afraid anybody without the technology would get sued for unsafe products, so they they collectively embargoed the technology.

    From the NPR write up:

    Industry sources say the major manufacturers also worry that adding the safety brake to some table saw models but not others would make them vulnerable to lawsuits.

    • I thought the manufacturers were just relucatant to give 10% of the gross of every saw they sold to the guy who patented it. Basically, they liked the idea, but they'd have to increase the price of their saws by 5% or so to compete, and that's a lot of markup in a relatively competative marketplace.

      Basically, it would have been like the guy who invented seatbelts requiring a licensing fee of $500 for each car they're installed in (back in the 50s).
  • by awing0 ( 545366 ) <<gro.hcetdab> <ta> <mada>> on Monday August 14, 2006 @10:39AM (#15902559) Homepage
    The fact that this may be mandatory bothers me. It's like seatbelt laws, lawnmowers that stop running when you get off the seat, and coffee cups with warnings. I'd say, let the market sort this one out. Yes it's cruel, but feel free to give me a Nelson "ha ha" when I run my hand through a chop saw.
    • by jandersen ( 462034 ) on Monday August 14, 2006 @11:37AM (#15903065)
      I'd say, let the market sort this one out

      This seems to be the new religion - at least in the US. 'The market' isn't some magical cure-all that is going to sort everything out and make the world a better place. Experience shows that free-market capitalism doesn't exist, among other things because every time restrictions are removed from businesses, we get monopolies, kartels and all the other diseases of extreme capitalism; thus, even if there are no restrictions imposed by the state, the free market will quickly be killed off by predatorial companies.

      Instead of this pipe-dream about the holy and divine 'free market' there should be simple and clear restrictions in place that would favour the small to medium sized businesses; the bigger companies are simply extremely inefficient in a number of areas; in a small company each employee often has a big stake in the success of the company and will work harder and not waste resources. A big company will tend to extract money from society into some form af passive storage, possibly overseas, whereas in small companies the money tends to get spent in the local area to the benefit of everybody.

      So let's put this silly, religious free-market mantra to one side; it won't benefit you or me (unless you happen to be a multibillionaire).
  • Table Saw Safety (Score:5, Insightful)

    by clintp ( 5169 ) on Monday August 14, 2006 @10:40AM (#15902572)
    I *have* had a finger get chewed through by a table saw.

    I was cutting a piece of wood that was way too small for a table saw to cut safely and it got my index finger. An avulsion laceration about 1/8" wide, right across the fleshy pad of the finger, down but not quite to the bone.

    My fault, I know. I didn't sue anyone, and wouldn't have thought to even if it took my hand. [For a cut that small and precise, I should have walked out to the workshop and used a band saw or built a jig. But I was lazy...]

    This is a great idea, but like another poster said it has to be cheap, and it has to be non-obtrusive. The safety of the device is a trade off against its utility. If the saw stops working because of a faulty safety switch, the safety switch will get removed. If it's expensive to replace, it will probably not be replaced.

    For example, my table saw has a kick-guard that goes over and behind the blade. It's an incredible pain in the ass because gets in the way, it's hard to see around, and makes some cuts damned-near impossible. It was removed.

    Make it cheap and make it reliable, and then it'll actually save some fingers.
  • by frogstar_robot ( 926792 ) <> on Monday August 14, 2006 @10:41AM (#15902579)
    Boy! Is my face red?!?
  • by RembrandtX ( 240864 ) on Monday August 14, 2006 @10:45AM (#15902617) Homepage Journal
    Its been around for years, and has been shopped to the major power tool manufacturs [one of the largest, I used to work for, so i'm not talking out of my butt here.]

    All of them turned it down due to legal implications, as well as adding to the cost per unit price.

    Leagally, if a power tool manufacturer added this to their existing line of table saws, it *COULD* be taken as an admission of guilt that their previous models were not safe, any accident cases (no matter how stupid) would then have another chance at a successful suit.

    Also, the inventor has been lobbying for *YEARS* to get his invention as a required component of table saws. He hasn't even had success in California - the most liberal state for passing stuff like this - let alone elsewhere.

    I'm not knocking his invention, I've seen it pitched first hand .. the guy whipped a raw hot dog at the blade as fast as he could, and there was only maybe 1-2mm of damage to the hotdog before the blade dropped down into the brakes.

    Destroying the blade of course. which .. at $50+ a pop .. kinda hurts.

    Another reason this hasn't been adopted yet is that pressure treated wood also tends to cause the brakes to fire off ..
  • There are two problems with this invention:

    - The inventor wants to extort 8% of the price of each saw
    - This opens the door for all sorts of product liability lawsuits

    Its interesting that this idea gets universal acclaim, while software inventions covered by patent are almost universally reviled. The reason that you're hearing about this at all is that the inventory is a savvy patent attorney who is going to eventually use government regulation as a club to make a huge amount of money.

    The pro
  • by Chirs ( 87576 ) on Monday August 14, 2006 @10:49AM (#15902652)
    For the non-woodworkers in the audience, this tech has been available for several years, and information on it was available for at least a year before the saw itself.

    The "Sawstop" modifies the electrical potential of the blade, and can thus detect when skin hits the blade. Of course it also triggers if you cut metal, so it has a disable switch. Apparently wet wood doesn't trigger it.

    When it detects flesh, it has an explosive charge that rams a chunk of aluminum into the blade stopping it within ~3ms. I saw it demoed in person at a wood show. The demonstrator slid a hot dog into the blade at a fair speed and there was a large bang. The hot dog had been cut into maybe 1/32" or so (a bit under a millimetre).

    The main problem is that the inventor wanted huge royalties from existing tool companies, and tried to force through legislation making it mandatory to include the device on *all* table saws in the US. As you can imagine, people were less than impressed about having it rammed down their throats. Even now, the saw that incorporates this is a very nice saw, but they still charge about 30% more than for other comparable saws.
  • Fantastic tech, but needs some improvement. It uses a fusible wire to activate the blade brake, which must apparently be replaced when it gets a "false positive" (which is apparently common when cutting wet wood). If this is to be adopted on a consumer scale, it needs an easily-resettable safety system, more like a circuit breaker than a fuse. Depending on the scope of his patent claim, there may be room for a number of competing improved safety mechanisms based on his idea, which could solve some of the
  • Not so great (Score:5, Insightful)

    by MatD ( 895409 ) on Monday August 14, 2006 @11:15AM (#15902876)
    I've been reading about this (and talking to thel company about it long before it ever got produced). This is a good invention, but I wouldn't buy one. Here's why.

    You can't cut green wood (wood that hasn't sat around long enough to get down to 10% water). I've gotten construction grade lumber that would easily have tripped this.

    Most accidents on the TS aren't from people accidentally putting their hand in the path of the blade, it's from them either slipping (in which case they are essentially slapping the blade, and will still get a very serious cut), or from kickback. I believe (though I don't have a source) that most accidents are from kickback.

    Also, many people take the blade guard that is included with their saw off becuase they think it gets in the way (which I've never really understood). If you were to look at the number of accidents on the TS, I would be willing to bet that most accidents involve a TS without a blade guard.

    Most damning though, is that when this unit does go off, your saw blade (that you pay $100 a pop for) is rotated down into a block of aluminum, and gets welded there from the heat. Even if you can extracate the blade from that block, it wouldn't be safe to use it again, so you have to buy a new blade, and a new cartridge.

    Table saws have been around for at least 100 years in their various forms and most woodworkers can still count to 10.

  • by hoggoth ( 414195 ) on Monday August 14, 2006 @11:45AM (#15903130) Journal
    "Do you expect me to talk?"

    "No, Mr. Bond, I expect you to get a 1mm cut and ruin my blade..."

  • by elmartinos ( 228710 ) on Monday August 14, 2006 @12:05PM (#15903320) Homepage
    If you care about safety, you absolutely have to see this great lift truck safety video []. Unfortunately it is in German, but you will definitely get an idea why safety regulations are so important :-)
  • Macho Men (Score:3, Insightful)

    by Detritus ( 11846 ) on Monday August 14, 2006 @01:57PM (#15904216) Homepage
    I'm disappointed to see all the posts from the "macho men" on slashdot, who think safety is for wimps, and if you saw your hand off, you're stupid and it's your fault.

    I hope that every time a worker loses fingers to a traditional table saw, their employer gets hit with a big lawsuit. Endangering yourself in your home workshop is your choice, but you shouldn't be able to impose that decision on your employees. I have an Uncle who was almost killed by a poorly maintained saw at his workplace. He lost part of one hand. It was pure luck that it didn't cut him in half.

    You can't assume that the equipment is in good working condition, and that the operators are properly trained and alert. You have to take active steps to regularly inspect the equipment for problems, perform preventive maintenance, train the operators on how to safely operate it, and make sure that everyone is actually following the safety rules. Any machine that relies solely on operator alertness to prevent an accident is an accident waiting to happen. Real people get distracted and have off days.

  • Safety aside..... (Score:5, Informative)

    by Sergeant Beavis ( 558225 ) on Monday August 14, 2006 @02:14PM (#15904360) Homepage
    Its actually a pretty damn good saw. I've used the SawStop cabinet saw at a couple of demos and I've been impressed with it. Losing a digit is always a concern, but anyone with a healthy respect for their tools will come away with fingers intact. Kickback is a much more dangerous situation because it can happen even when you are being careful. The SawStop has a self adjusting Riving Knife that prevents wood from binding against the rear of the blade and thus being thrown back at the end user. I've been into woodworking since I was 5. I've gone to many church and house rasing to help others and still volunteer my skills to Habitat for Humanity. In that time, I've been fortunate to keep my digits, but I've experienced the pain of kickback once. I was lucky to have gotten away with just a bruise. Kickback can flat out kill a person. Riving knives are very common on European built table saws, but are rare in the American market. We usually get a splitter with kick back cawls that should catch the wood as it gets kicked back. Normally it works well but a Riving knife prevents kickback in the first place. I can't think of one other US manufacturer that offers it on a cabinet or contractor saw. Saw Stop includes it on all of their saws.

    Outside of those items, the SawStop is also very well balanced, it has almost no vibration, even less that most other Cabinet Saws. The trunions are solid and move the blade into position with little effort from the user. It also has a magnetic cutoff switch positioned right above the users knee for quick shutdown. It also includes a Biesemeyer style fence. Its only real drawback is that it is very expensive at $2800 for the basic saw. Options can run well over $5000. While I still like it, that money could be better spent on a European Combination Machine such as the Laguna or a Delta Unisaw with alot of money left over for other tools.

  • by ( 213219 ) on Monday August 14, 2006 @03:31PM (#15905120) Journal
    It can happen so quickly and easily that when it happens you don't even know that it has happened. The cut doesn't hurt as badly as you would imagine, in my case it felt like I was touched with a feather. It was just a very light brushing sensation although my mind knew immediately what had happened.

    I was very lucky, I did not cut any bone and I only lost a strip of tissue about an inch long, maybe 3/8's of an inch deep and 3/32's of an inch wide out of my thumb. Still it was a sobering experience that left a piece of expensive oak ruined (not to mention the blood rushing out of my thumb). What happened is that I was making numerous identical cuts and I got a bit bored and for just a moment I didn't think.

    I try not to be stupid around power tools; I am not a professional, just a hobbyist and am very aware of my relationship to my tools. While I have learned to trust them, I have also learned to distrust them and always try to be as safe as possible. I think that the table saw is probably one of the more dangerous tools in the typical wood shop simply because there are so many times when you have to work with this guard removed or you are tempted to make a fine adjustment with the power on.

    I am frankly a bit offended by the industries lack of enthusiasm for this kind of product (although on the flip side, I also understand that it would make every new saw much more expensive). The power tool industry is very aware that their products can cause serious injury (up to and including the loss of life). When they have an opportunity to make their products cheaper, they are morally obliged to do so. While this high-tech solution my have some shortfalls, it is obviously a step in the right direction. I suspect that the industry can find ways of making similar safety devices that work in different ways if they want to or are "encouraged" to. .

How many NASA managers does it take to screw in a lightbulb? "That's a known problem... don't worry about it."