[HN Gopher] CT Scans of New vs. Used SawStop
___________________________________________________________________
CT Scans of New vs. Used SawStop
Author : saltypal
Score : 160 points
Date : 2024-12-08 23:56 UTC (23 hours ago)
(HTM) web link (www.lumafield.com)
(TXT) w3m dump (www.lumafield.com)
| WillAdams wrote:
| Does making tools more expensive really benefit anyone other than
| the companies which own the patents which make them more
| expensive?
|
| Of these 30,000 injuries per year, how many happen when the blade
| guards are removed? How many happen when a push stick is not
| used? How many happen when a person stands in the direction that
| a piece of wood will be thrown by kickback? Once all those are
| subtracted are there enough injuries to count?
|
| What if all tablesaw injury cases were tried by a jury of shop
| teachers?
|
| The best advice I got in shop class was to slowly and quietly
| count to 10 on my fingers before throwing a power switch and in
| doing so to envision the operation from beginning to end and all
| the forces which would be involved, and to remind myself, that I
| wanted to be able to repeat that cut when the power was turned
| off.
|
| SawStop goes on about how they will license their patent, but the
| licensing being offered is a very narrow one and doesn't seem to
| include the entirety of their patent portfolio, and they have
| fought very hard to keep tools with similar capabilities out of
| the U.S. market claiming patent infringement.
| unsnap_biceps wrote:
| You're not required to purchase them if you don't want to.
| Personally, I have a stopsaw. It has never triggered, so beyond
| initial purchase price, it hasn't cost me a cent extra, but in
| the unlikely case where I do something dumb or have an
| accident, I feel better knowing it won't be life altering and
| all I'll need to do is replace a blade and a $99 cartridge.
| That's worth it to me.
| abakker wrote:
| likewise, but also worth noting that the saw stop saw is just
| a...nice saw. Better than the old delta I used to have,
| better than the powermatic 66 that I grew up using. Probably
| not as nice as my buddy's $20k sliding Felder saw, but...for
| the price, a Sawstop is a nice tool and highly competitive in
| build quality.
| Blackthorn wrote:
| To be fair, other companies haven't been trying very hard. I
| hate Felder for this. They have their own tech to drop the
| sawblade when they sense fingers. And they use it as a form of
| market segmentation, only offering it on their $30k+ tablesaws
| and not on their less expensive ones.
|
| > The best advice I got in shop class was to slowly and quietly
| count to 10 on my fingers before throwing a power switch and in
| doing so to envision the operation from beginning to end and
| all the forces which would be involved, and to remind myself,
| that I wanted to be able to repeat that cut when the power was
| turned off.
|
| It's great advice, but injuries tend to happen when people
| become complacent with the operations.
| mlyle wrote:
| > Of these 30,000 injuries per year, how many happen when the
| blade guards are removed? How many happen when a push stick is
| not used?
|
| Seems like you don't buy into the swiss cheese model of
| accidents. Because other safety mechanisms and good practices
| exist, it doesn't mean that there's not reasons to add
| additional safety. In aviation, we always blamed the pilots for
| a long time, and it wasn't entirely wrong. However, no matter
| how much we told pilots "stop crashing and dying!!" they didn't
| seem to want to stop.
|
| This is there for the day when other things go wrong-- when a
| tired operator reaches for something he obviously shouldn't;
| when a blade guard is out of place and someone slips; when
| someone who isn't sufficiently trained doesn't realize he
| shouldn't use the table saw.
| bigstrat2003 wrote:
| > Seems like you don't buy into the swiss cheese model of
| accidents. Because other safety mechanisms and good practices
| exist, it doesn't mean that there's not reasons to add
| additional safety.
|
| I think it's reasonable to say "we have done enough" at some
| point though. We can debate where the point is, but safety is
| not an unalloyed good. It has a cost, and reasonable people
| can disagree over whether a particular safety invention has
| enough ROI to justify its existence.
|
| For example, we wouldn't countenance banning all motor
| vehicles even though we could eliminate all car related
| deaths with that one simple trick. We would get a fair bit of
| payoff, but the cost would just be too high to justify it.
| Similarly, if we could inflict a very minor cost on everyone
| in the world to prevent one death per year, that would be too
| low of a payoff even though the cost is very low.
|
| So yes, we can always add more layers of defense against
| accidents (or security incidents). But eventually, the juice
| isn't worth the squeeze and you stop. So I don't think the
| Swiss cheese model really can justify any particular
| intervention by itself; you have to evaluate the specifics of
| whether the particular intervention is worth it.
| toast0 wrote:
| > I think it's reasonable to say "we have done enough" at
| some point though. We can debate where the point is, but
| safety is not an unalloyed good. It has a cost, and
| reasonable people can disagree over whether a particular
| safety invention has enough ROI to justify its existence.
|
| That has to be a point in time decision though. Closed
| circuit TV backup cameras in cars have been possible since
| I dunno, probably the 70s, certainly 80s technology _could
| have_ done it; but they weren 't a reasonable intervention
| (outside of say armored cars for currency transports) until
| more recently as cameras and displays have gotten less
| expensive and quality has improved. Also helpful as modern
| vehicle design has resulted in significantly reduced
| visibility compared to the past, but that's a rant for a
| car article :P
| bsder wrote:
| The saw manufacturers all blew off SawStop because they were
| worried that they would now be liable for any injuries which
| still occurred.
|
| Simply make table saw manufacturers liable for _any_ injury
| from the saw and this kind of mechanism will instantly become
| default.
| Animats wrote:
| Yes, they did. They even tried to legislate against SawStop.
| See "H.R. 8181: Preserving Woodworking Traditions and
| Blocking Government-Mandated Monopolies Act"[1] Didn't go
| anywhere.
|
| There is supposedly woodworker opposition.[2] "Many
| woodworkers argue that the implementation of SawStop
| technology has disrupted traditional woodworking practices.
| Some feel that it has altered the craft in a negative way by
| making it less reliant on skill and attentiveness, instead
| placing an emphasis on technology to prevent accidents. This
| shift in focus is seen as a departure from the fundamental
| principles and values of woodworking." However, no actual
| woodworkers are quoted, and the author has a tool store, so
| this is probably astroturf PR. That web site is addressed to
| people with a semi-religious attitude towards woodworking,
| not to working carpenters or cabinetmakers.
|
| (Having used circular wood saws, I am all in favor of blade-
| stop devices.)
|
| [1] https://www.govtrack.us/congress/bills/118/hr8181/text
|
| [2] https://www.woodworkcenter.com/why-do-woodworkers-hate-
| the-i...
| bawolff wrote:
| > "Many woodworkers argue that the implementation of
| SawStop technology has disrupted traditional woodworking
| practices. Some feel that it has altered the craft in a
| negative way by making it less reliant on skill and
| attentiveness, instead placing an emphasis on technology to
| prevent accidents. This shift in focus is seen as a
| departure from the fundamental principles and values of
| woodworking."
|
| Wow. This is basically: real men enjoy getting their
| fingers cut off.
| duskwuff wrote:
| Ideologically speaking, it's the same sort of people that
| opposed seat belt laws in the 1980s on the grounds that
| they'd encourage risky behavior by drivers. (They don't.)
| DannyBee wrote:
| #2 is becuase woodworkers as a group are fairly
| conservative.
|
| TTI and friends were very effective at riling them up. I
| belong to a number of significant woodworking forums/etc,
| and have watched the manipulation over the years firsthand.
|
| This was mostly in the form of "big daddy government wants
| to make you pay for more saws because of dumb people", so
| the take they have there around the craft itself is pretty
| funny.
| bagels wrote:
| It's so silly. The saw stop doesn't reduce the amount of
| skill needed to use it, and you're still free to be as
| attentive as you like. If they really followed this to its
| logical conclusion, they'd be using unpowered stone tools
| to do woodworking.
| dyauspitr wrote:
| That's terrible though. You can't make knife manufacturers
| responsible for everything a knife does.
| bawolff wrote:
| I think the idea is that if someone advertizes their saw as
| safe, but it isn't, then there should be some liability.
| Like if you make a fake safety saw or imply its much more
| safe than it actually is you should get in trouble.
|
| But surely there must be some middle ground between a
| company making a fake safety saw, and a good faith effort
| that isn't quite perfect.
| dyauspitr wrote:
| I don't think any saw manufacturer says anything about
| their safety besides warning you about not using the
| riving knife and blade guard.
| krisoft wrote:
| We are getting confused here.
|
| The claim was "The saw manufacturers all blew off SawStop
| because they were worried that they would now be liable
| for any injuries which still occurred."
|
| Meaning that table saw manufacturers were worried if they
| implement SawStop like safety feature, and they advertise
| their saws as safer they become liable for times when the
| technology does not work.
|
| So yes, you appear to be correct what saw manufacturers
| say about their safety now, but that's not the point we
| are discussing. The point is that if they add a SawStop
| like feature and advertise it then they would be talking
| about the safety of their saws.
| lazide wrote:
| People still try, and depending on the public's mood
| sometimes it sticks.
| bsder wrote:
| The difference between the accidental damage a knife can do
| versus what a circular saw can do is night and day. And I
| say this as someone who needed surgery after cutting
| through a tendon with a knife. :(
|
| Old school radial saws, for example, basically don't exist
| anymore at the consumer level. They were simply too
| dangerous. Slider-type miter saws have almost completely
| replaced them.
|
| Personally, I would even go so far as to suggest that
| weekend woodworkers should avoid even having a table saw,
| period.
|
| The main problem with table saws is that they become a "do
| all" machine even for those kinds of actions that really
| shouldn't be done on it. You're already at the table saw,
| and it's often _really_ convenient to just "sorta kinda"
| bodge something up on the table saw rather than doing the
| safe thing and changing the blade, putting together a real
| jig or using a completely different tool.
|
| If you have a track saw or a cheap CNC instead, the danger
| level is way, way lower, and the result is probably a lot
| better.
| WillAdams wrote:
| Have you checked recent legal cases against gun
| manufacturers? Some are not too far removed from suing a
| battery manufacturer because someone took the acid from a
| battery and used it in an attack?
|
| Traveled to New York City or the U.K. recently? Check your
| pocket for a locking blade, or an assisted opening knife
| before-hand.
| Spooky23 wrote:
| The difference there is they funneled a lot of marketing
| dollars into pseudo education and astroturfing campaigns
| to create a sense of hysteria that the boogeyman was
| coming for the guns, specifically the now dizzying array
| of AR-15 derivatives and pistols.
|
| That essentially contributed to a gun buying bubble and
| solider cosplay.
|
| This
| RajT88 wrote:
| > Does making tools more expensive really benefit anyone other
| than the companies which own the patents which make them more
| expensive?
|
| I would pay thousands to avoid losing part of my hand. The
| increased price is a very good value, tens of dollars.
|
| Look at rearview cameras. Cheap tech. Used to be a 1000+ USD
| option. Now that they are government mandated the manufacturers
| figured out how to include them for a couple hundred dollars.
|
| Price goes up, but just a little. Money well spent.
| PaulDavisThe1st wrote:
| > I would pay thousands to avoid losing part of my hand.
|
| I cut off the distal segment of my right thumb on a table saw
| in 1995. The initial bill, before I disputed it and received
| a "professional courtesy discount", was $25k.
|
| So, you can pay a relatively small price to avoid losing part
| of your hand, or you can gamble that it will never happen,
| and then pay a high price for losing part of your hand.
|
| Pretty simple choice to me.
|
| ps.
|
| Doctor: what do want to do with the rest of your life?
|
| Me: well, I'm a programmer right now, but I'd rather be
| farmer
|
| Doctor: I know a lot of farmers with less digits than you
| still have, and you'll still be able to hit the space bar as-
| is.
| atmavatar wrote:
| In effect, a SawStop system is like a one-time health
| insurance payment that prevents you from getting injured in
| the first place, only without jacking up the price because
| you used the tool in someone else's garage.
| numbsafari wrote:
| Good thing you and the doc weren't on opposite sides of the
| tabs v spaces discussion.
|
| Ed: The fact that you can hit the space bar with either
| hand, whereas the tab would require changing your keyboard
| layout is not a consideration I had previously considered
| in this debate.
| PaulDavisThe1st wrote:
| You might say that the doc and I were _aligned_ over the
| tabs vs spaces discussion. That is: tabs to indent,
| spaces to align.
| wat10000 wrote:
| Are you suggesting that injuries don't count if the operator's
| actions contributed to them and they're not worth preventing?
| WillAdams wrote:
| I'm suggesting that people should have a sense of personal
| responsibility when operating potentially dangerous
| equipment, and that a person should not be required to pay
| extra for a business or hobby just because some well-to-do
| patent lawyer has come up with a business model which has an
| end-game of requiring that patents from his company be
| required in products.
| Spooky23 wrote:
| Your way of thinking is why things like safety glass,
| headrests, and seatbelts were kept of of cars for so long.
|
| It's a fine principled argument, but stay the hell away
| from product management.
| lazide wrote:
| Just wait until you hear about building codes requiring
| mandatory AFCI and GCFI breakers.
| wat10000 wrote:
| You can't control what sense of personal responsibility
| people will or will not have. So saying that they "should"
| have it means absolutely fuck all.
|
| A requirement for this safety feature would be enacted in
| order to prevent a large number of accidental mutilations.
| It might make money for certain people and they might push
| it for that reason, but that's not the main purpose for
| enacting it.
|
| I look forward to your complaint that you're forced to
| spend money on seat belts you don't need.
| danparsonson wrote:
| > personal responsibility
|
| Ah personal responsibility! The magic bullet that mitigates
| all accidents.
|
| All of your personal responsibility will vanish the instant
| you injure yourself horribly - then you'll be wholly
| reliant upon numerous other people who will have to deal
| with the horror of what you've done to yourself, or else be
| delayed in receiving their own care because of it.
| Slyfox33 wrote:
| "Just don't make mistakes!"
| onlypassingthru wrote:
| > Does making tools more expensive really benefit anyone other
| than the companies which own the patents which make them more
| expensive?
|
| When it comes to table saws, you only have to make a mistake
| once to find out. Almost perfect doesn't cut it. (ba dum bum,
| tss)
| bagels wrote:
| Why have airbags in your car? All you have to do is not crash.
| ckozlowski wrote:
| This is Stumpy Nubs argument (YouTube:
| https://www.youtube.com/watch?v=nxKkuDduYLk); that patience,
| forethought, and use of a blade guard and other tools would
| prevent most injuries. I'm in agreement.
|
| But I don't think that companies are trying to make the tools
| more expensive. In fact, it was the opposite. SawStop sold
| high-end saws, other manufacturers did not want to adopt the
| technology because of the cost it added.
|
| The issue of proper saw safety and use of sawstop technology
| are two different issues, I believe. And while I agree, the
| proper safety procedures you cite should be used by everyone,
| they aren't. In fact, they often aren't. And we can sit here
| and shake our fingers, but it won't change the overall culture
| around them. And I think that's the conclusion that regulators
| have come to as well: They're not going to get people to always
| use their blade guards or count to 10, so they'll mandate
| adoption of a technology that mitigates the risk due to people
| not following directions.
|
| Regarding the licensing, I think that's been addressed by
| others elsewhere. But in short, SawStop defended their patents
| in order to license the tech. When the government moved to
| mandate it, SawStop said they wouldn't enforce their patent,
| but they're not handing the tech over either. Other companies
| are free to develop their own method without running afoul of
| SawStop's patents, or they can license SawStop's tech. To me,
| it seems like a fair approach that both protects their
| investment while not putting themselves in a morally
| questionable position in taking advantage of the upcoming
| regulation.
| andrewflnr wrote:
| Usually those fancy 3D displays are miserable on my phone, but
| the ones on this page pretty much just work. Lovely surprise.
| zo1 wrote:
| Ironically, previous ones worked beautifully for me but this
| one fails on my desktop Firefox. Couldn't even select text on
| the page to copy paste, utter failure.
| andrewflnr wrote:
| Just checked. It was indeed a lot worse on my more powerful
| linux desktop than my android phone. Firefox in both cases.
| Computers are stupid. :D
| chewbacha wrote:
| Wait, so is it a one time function? Can the wire be reset?
| GiorgioG wrote:
| IIRC you need to replace the brake cartridge and the blade.
| isatty wrote:
| AFAIK all sawstop catridges are one time use only and also
| destroys the disk. This is not really a bug.
| lazide wrote:
| Yeah, reliably stopping a heavy very fast spinning object in
| just a few degrees of rotation is necessarily violent.
| DannyBee wrote:
| Actually not. My handguard saw will do as well as the
| sawstop non-destructively (independently tested and
| verified, so you don't have to take their word for it).
|
| They do it (basically) by predicting whether your hand will
| touch the blade, rather than waiting until it _does_ touch
| the blade.
|
| If you wait until someone actually touches the blade, then
| yes, you have to operate very very fast. That is
| unavoidable due to physics, as you say.
|
| But if you can gain 100ms or 250ms by proving a 100%
| probability that the hand will touch the blade before the
| person can stop it, you now have a lot more time to stop
| the blade.
| lazide wrote:
| How is that going to work reliably with sawdust and the
| like everywhere? Some kind of radar?
| Snoozus wrote:
| two cameras
| DannyBee wrote:
| also, the saws do not produce dust everywhere. these are
| European saws. Dust extraction is not only required on
| the saw, It's required by law in the workplace. This saw
| will not operate unless the safety + extraction hood is
| in the proper position and dust extraction is hooked up
|
| I can show you a video of an air quality meter sitting
| between the cameras and the saw hood if you want. The
| amount of particle change is minimal
| Fraterkes wrote:
| Ive looked at the saw you mention in another comment, and
| in all honesty Id much rather have a safety precaution
| that works based on very simple physics (like sawstop)
| than some black-box ai hand detection algorithm.
| DannyBee wrote:
| To each their own. Computer vision of this kind is not
| like cutting edge ai. This is pretty standard fare and
| has been for decades
| kevin_thibedeau wrote:
| Optical mice fail with too much dust on the lens. It's
| risky to depend on a vision system in a machine that is
| generating dust.
| DannyBee wrote:
| Have you considered that they've thought of this?
| Seriously.
|
| This is company producing high end sliding table saws
| that cost tens of thousands. They've been at it for over
| half a century.
|
| This is not someone producing a 299 saw as cheaply as
| possible.
|
| They are a German company (ie regulated heavily) and have
| a ridiculous number of safety standard certifications
| that test things like "what happens when there is dust"
|
| do you really think they haven't thought of the obvious
| basic issues and figure out what to do about them?
|
| if so, what evidence do you have that this is true?
|
| (Also I think you don't understand European requirements
| on dust extraction and allowed exposure to wood dust.
| This saw does not produce a meaningful anount of dust)
| beepboopboop wrote:
| I've seen more bugs in software rather than hardware,
| I'll tell you that.
| stavros wrote:
| But what can happen that will mean that your finger will
| touch the blade in a quarter of a second?
|
| I can't think of anything, short of dropping a person on
| the saw.
| danielheath wrote:
| Holding a piece of wood and sliding it along a table saw
| (to cut it) is the canonical method for losing a finger,
| and you could definitely pick that out with a relatively
| simple bit of computer vision.
| stavros wrote:
| Yes but there's no way for me to not be able to pull my
| hand back in a quarter of a second for that.
| DannyBee wrote:
| Are you saying you tink you will notice and react?
|
| Because that's what doesn't happen and people lose
| fingers.
| rcxdude wrote:
| Finger movements are generally on the order of 1-2Hz, a
| hand holding a large piece of wood will generally be much
| lower than that, which means that at the hundreds of
| millisecond level most of the movement can be predicted
| from momentum alone. Something which identifies and
| tracks hands in a view and fits a second order model to
| the movement can likely predict accurately enough at that
| timescale to make for a meaningful safety improvement
| (especially because if it's non-destructive you can tune
| it to err more on the side of caution than a destructive
| option)
| stavros wrote:
| Hm yeah, I guess you're right, if it's non-destructive it
| doesn't matter much if it's wrong.
| bradly wrote:
| The blade doesn't have to stop. Some saws have the entire
| blade assembly lower. If you walk the table saws at AWFS
| you'll see all types of different safety systems.
| smoyer wrote:
| It's sacrificial ... So that your finger is not.
| shrubble wrote:
| There is a removable cartridge that stops the blade. It ruins
| the blade. The cartridge gets swapped out with a new one in a
| few minutes (the table top of the saw can be partially opened)
| and costs about $150 .
| beacon294 wrote:
| > When the brake is activated, the most recent data is stored
| into memory and SawStop can download the data from the
| activated cartridge. This data is very important to our
| continuing research and development program. If SawStop's
| engineers verify the activation was due to contact with skin,
| you will receive a free replacement cartridge. If you are
| unsure why the cartridge activated, you can also ship the
| cartridge for analysis to SawStop's service engineers. When
| the cartridge data is downloaded, we then can determine what
| specifically caused the brake to activate so that further
| unintended activations can be prevented. The brake cartridge
| evaluation is free of charge the shipping of the brake
| cartridge is paid for by the customer.
|
| https://www.sawstop.com/service-tips/what-to-do-if-the-
| sawst...
| davesmylie wrote:
| It _may_ destroy the blade. I've had mine for about 10 years,
| and have had two false triggers in that time (both times, dumb
| mistakes on my part). Neither time has the blade been
| destroyed.
|
| One of them did require a resharpen though.
| op00to wrote:
| What did you do that caused it to false trigger?
| davesmylie wrote:
| I sometimes mill my own lumber from windfall on my property
| - in the first instance somehow I managed to put a single
| piece of near green lumber (~40% moisture) in the same rack
| as some lumber I knew was dry.
|
| A few weeks later I needed some scrap for something,
| grabbed the piece closest on hand, pushed it into the blade
| and immediately triggered the wet wood alert and the blade
| spun down slowly. I knew that the wood wasn't wet, so
| started the saw up again and pushed it straight back into
| the blade only with more force, triggering it straight
| away.
|
| Second time was due to cutting a lot of pitch heavy pine
| over an extended period of time - it built up on the
| cartridge and after a blade change that I didn't check the
| clearance on, it bridged the brake with the blade (i
| assume) and triggered on start up. (It comes with a tool to
| check this clearance after a blade change - I of course did
| not follow the instructions).
| dyauspitr wrote:
| How does it distinguish between wet wood and a finger?
| Also does this mean you can't use the saw stop on fresh
| pressure treated lumber?
| lazide wrote:
| 1) it can't really tell reliably.
|
| And
|
| 2) correct.
|
| You can manually disable the auto--trigger mode in those
| situations though (bypass mode).
|
| It also doesn't like anything conductive - so anything
| coated with Mylar, any kind of conductive dust or debris,
| etc. is also a crapshoot.
|
| Very much edge cases though, unless you're dealing with a
| lot of randos. A workshop I used to share had a wall
| covered with sawstop 'trophies', due to people doing
| weird stuff.
| davesmylie wrote:
| You can use wet wood or pressure treated lumber or even
| foil coated acrylic - but the key is that you need to be
| expecting this, and you put the saw in to by-pass mode.
|
| At that point, it's just another dumb saw that will chop
| your finger off, but it won't trigger the cartridge, and
| you can make what ever cuts you need.
|
| The way it tries to determine if it's wet wood / a body
| part is the capacitance change. Slightly different
| profile which they can use to make an educated guess
| (obviously erring on the side of caution).
|
| This is why for some time they would give you a free
| cartridge if yours triggered on flesh - they wanted the
| data on there from real-life flesh contact to improve
| their calculations.
| morcheeba wrote:
| Ah, that explains why there is so much electronics in the
| cartridge! It seemed a bit like overkill, but returning
| the cartridge will get them their data.
| cyberax wrote:
| > This is why for some time they would give you a free
| cartridge if yours triggered on flesh - they wanted the
| data on there from real-life flesh contact to improve
| their calculations.
|
| The automatic defibrillators manufacturers also will
| often send you a unit for free if you used your unit for
| an actual defibrillation. Same idea.
| bradly wrote:
| I've triggered one by touching the blade too soon after it
| has stopped. There is a short delay between when the blade
| stops and when the brake is disabled. I've also had one
| trigger on a heavy miter through some gnarled 8/4 walnut.
| fasthands9 wrote:
| Mostly unrelated, but I don't think SawStop is releasing its
| patent anytime soon like the article states. That SawStop press
| release was the CEO saying they would do so if the CPSC rule was
| passed, but the rule wasn't voted on. And even then they were
| only releasing one of their hundreds of patents.
| voisin wrote:
| I recall reading that the majority of their patents were
| expiring in the next few years and the one that they've offered
| to not enforce (rather than release) is the important one that
| doesn't expire until the 2030s.
| dpkirchner wrote:
| Yup -- Planet Money did a podcast about the sawstop and
| talked about the patents and controversy:
| https://www.npr.org/2024/09/20/1200551215/sawstop-steve-
| gass...
| fastball wrote:
| It says that at the end of the article.
|
| > Despite previous litigation against would-be imitators of
| their safety brake, SawStop has committed to dedicating its
| original patent to the public when these new regulations go
| into effect.
| fasthands9 wrote:
| My comment is pointing out that the regulations will never go
| into effect.
|
| The scheduled vote on the regulations was postponed this
| year, and it seems unlikely it would pass once it becomes
| Republican majority next year.
| DannyBee wrote:
| They've pretty explicitly been willing to release all of the
| relevant patents. The truth is it was always a red herring for
| their competitors. The major players all have systems that
| don't rely on these patents.
|
| Lawsuit discovery showed all of them had developed their own
| technology that was fine, patent wise. But it would have eaten
| into their profit.
|
| Personally, I have an altendorf handguard sliding table saw,
| which will stop as fast as the sawstop, but not destroy the
| blade.
| fasthands9 wrote:
| That table saw looks very nice, but also $7,000? That's not
| the same market that people are talking about.
|
| I'm not so sure if other companies have the ability at a sub
| $2000 price point! Bosch came out with their own system that
| they thought was different. The product was on shelves for a
| year and then SawStop successfully sued. If a major company
| like that is unable to do it even after their lawyers gave
| them the clearance, I'm a bit dubious it's that easy.
| DannyBee wrote:
| Sure it's a pro saw.
|
| Evidence from the lawsuits says they could do it at the 299
| or 399 price point. Cost per saw was like 50 bucks.
| david38 wrote:
| Damn. I've wanted one of those for years. What model and what
| did it set you back?
| close04 wrote:
| I think free access to use the patented tech is only a part
| of the answer to building such a mechanism, and definitely a
| good first step. Looks to me like the build quality would
| make an even larger difference to the success of the device.
| For example:
|
| > The fuse wire is designed to be stable enough to resist
| stretching or thinning over time despite the intense repeated
| vibrations from the saw use, ensuring it doesn't prematurely
| release the spring.
|
| "Just" some bad QA and the wire releasing the mechanism
| breaks too early needlessly destroying the saw, or too late
| needlessly destroying the hand. A patent won't fix that for
| the manufacturer.
| DannyBee wrote:
| I agree on all of this. But the others had already done the
| r&d. Take a look at the documents in the Massachusetts
| table saw injury lawsuit, from 2006, an example.
| jchw wrote:
| I would be glad to see better table saw safety mechanisms, though
| I'm skeptical that 1. This will actually happen 2. That patent is
| the only one that will wind up mattering.
|
| I can't help but wonder if a big part of the reason the number of
| incidents is so high is because we're intentionally hyperbolic
| about risks when it comes to warning labels, for liability
| reasons. As an example, many appliances will warn that you can
| never operate them with the covers off and doing so can cause
| death or serious injury. Okay fine, sure, it's not necessarily
| safe, and perhaps you could indeed kill yourself by accident
| doing so. However, in practice it's bullshit. People do this all
| the time, and you pretty much have to sometimes. How the hell are
| you even supposed to troubleshoot without being able to see
| what's wrong? Just guess?
|
| So sometimes when it comes to warnings it's easy to empathize
| with the person who didn't take them very seriously, as we're
| pretty much conditioned to take warnings like this with a grain
| of salt.
|
| Though honestly, when it comes to using a table saw, the thing
| I'm actually afraid of is kickback. Amputation risk is still very
| serious of course, but I feel safe enough with the many layers of
| mitigations I already use. I don't want to fall into complacency,
| but I also don't think I'm going to lose sleep over not having a
| SawStop table saw either. (I am not using my table saw often
| enough for it to be a terrible concern anyways.)
| GuB-42 wrote:
| My grandfather is 90, he was a woodworker, he lost two fingers
| to a table saw. Few woodworkers of his age have 10 fingers.
| Workshops are much safer today and woodworkers can expect to
| end their career with all their fingers. That SawStop thing is
| one of the many things that can contribute to it.
|
| The idea that safety features cause complacency has been
| debunked several times. Statistically, well designed safety
| features or equipment reduce accidents, even if it may cause
| some people to get complacent.
|
| And you are right to be afraid of kickback, and one of the
| risks associated with kickbacks is inadvertently touching the
| blade, that is the issue SawStop is designed to address. The
| blade guard helps too, but AFAIK, there are many instances
| where you can't use it.
| bamboozled wrote:
| Because as much as we know saw stop works. No one wants to
| actually find out if works.
|
| Disclaimer: cabinet builder.
| bradly wrote:
| > The blade guard helps too, but AFAIK, there are many
| instances where you can't use it.
|
| Blade guards are rarely used in shops I've worked in. I've
| even worked in a shop that removed the riving knifes on their
| saws as they got in the way of certain cuts and they didn't
| want to spend time taking them on and off.
| Implicated wrote:
| What sort of cuts would cause you to need to remove the
| riving knife?
| mym1990 wrote:
| Very beginner woodworker here, but dados(or any kind of
| groove are the ones that immediately come to mind.
| Essentially anything that has the work piece going over
| the blade, but not cutting through completely.
| lukaslalinsky wrote:
| You can keep the riving knife for those cuts, it causes
| no issue. just can't use the blade guard. I honestly
| can't imagine a cut that would require the riving knife
| off.
| 1-more wrote:
| Dado stack. It's a smaller diameter than the blade. You'd
| have to be pretty lazy to not just reinstall the riving
| knife when you put a normal blade back on, but I could
| see that happening.
| mym1990 wrote:
| I think people get complacent and if it a cut that one
| does fairly regularly, I could see someone saying on the
| 1000th cut "eh lets keep it off for this one time" and
| then it just becomes a thing.
| rocqua wrote:
| Plunging cuts, and 'cove' cuts. Also smaller blades like
| dado stacks.
|
| With a cove cut you move the fence to about a 30 degree
| angle to the blade, to get an elliptical cove along the
| length of a board. It's a rare thing to need. But if you
| really need a wide cove, it might be hard to get a router
| bit to do that.
| ckozlowski wrote:
| Stumpy Nubs over on YT gave some testimony where he
| believes that a well-made blade guard could prevent most
| injuries. He believes that it's a culture around not using
| them (or poorly-made ones) that is the source of most
| injuries.
|
| Timestamped for convenience:
| https://www.youtube.com/watch?v=nxKkuDduYLk
| AlotOfReading wrote:
| Every tradesman knows people that actively refuse to use
| PPE and other safety equipment. There's are huge social
| stigmas against it in most crews.
| antihero wrote:
| Does that mean decorating helmets with union stuff is
| actually a great marketing win for safety?
| Spooky23 wrote:
| Totally. It's also evidence that the control has been
| accepted and incorporated into the workers
| identity/image.
|
| You see it in utilities. Gas workers will helmet up
| swapping out a meter head.
| bluGill wrote:
| The blade guards on the cheap tablesaws are awful and
| everyone removes them. The good table saws come with
| guards that work much better (but still not perfect
| sometimes you have to remove them but most of the time
| they work well). You can buy a new table saw for under
| $100, a good blade guard can be bought separately for
| $300 so you see why a lot of saws have cheap guards.
| (note that the cheap tablesaw too light duty to support
| the good guard)
| bradly wrote:
| > I can't help but wonder if a big part of the reason the
| number of incidents is so high is because we're intentionally
| hyperbolic about risks
|
| I've work in multiple production furniture shops and that has
| not been my experience. People are just moving fast, trying to
| get stuff done and things happen. Also, training safety in a
| non-educational setting is tough.
| jchw wrote:
| Yeah, see, I actually just simply don't know what the
| breakdown of the 30,000 incidents per year is. I would've
| guessed a large number of those incidents were from hobbyists
| and not professionals, and I would guess that the mistakes
| hobbyists make are different in origin from the mistakes
| professionals make, even if they have common threads. If it
| so happens that it's actually mostly professionals losing
| fingers, then I'm barking up the wrong tree with this.
| inferiorhuman wrote:
| I'd wager the opposite. A hobbyist will typically have a
| healthy fear of a table saw because one of the first things
| someone learns about a table saw is that it will fuck you
| up without a moment's notice.
|
| A pro in a hurry? Not so much. It's the pro that's gonna
| remove the safety guard and riving knife, be invested in
| expensive blades they don't want to replace if the
| cartridge goes off accidentally, etc., etc.
| harrall wrote:
| I've also seen many hobbyists do cuts on table saws that
| seem to encourage danger and then they stand right in the
| way too. Then they complain that "no one could have
| predicted this."
|
| The worst one I've seen is someone cutting circles on a
| table saw (already normally a no) with their hand behind
| the blade on the side that pulls you in instead of
| cutting (the kickback side). And it pulls his fingers
| right into the blade. (Saved by SawStop though.)
|
| Heathy fear does not mean they know how the saw works at
| all. So I'd say both sides are apt to lose fingers.
| bluGill wrote:
| The pro knows the safety stuff too, but they get into a
| groove (we call it the zone in programming) and start to
| take shortcuts to go faster without noticing their
| fingers are getting closer and closer to the blade.
|
| The hobbyist doesn't enough to get into a groove and so
| won't have that happen. However the hobbyist is doing
| many different cuts and so doesn't always remember how to
| do each safely.
| Hilift wrote:
| > I can't help but wonder if a big part of the reason the
| number of incidents is so high is because we're intentionally
| hyperbolic about risks when it comes to warning labels
|
| Chainsaws have about the same number of annual ER visits as
| table saws. It's common to see someone using a chainsaw without
| most of the recommended safety gear. In those cases, it's
| probably money.
| jdprgm wrote:
| Off topic but I wonder how broadly the idea of very expensive
| failure scenarios but human damage is avoided could be applied to
| industry at large...
| bluGill wrote:
| Depends on the system. This would be my second to last choice
| as an engineer. First choice should always be design the system
| so you can't get hurt in the first place - but nobody has any
| ideas on how to do that to a table say (or we have ideas but it
| no longer can do the job of a table saw and so must reject
| them). Second is to put guards in places - we have been doing
| that since at least the 1980s (probably before, but I'm not old
| enough to remember), but guards are not perfect and so people
| still can lose a finger even with guards used correctly (cheap
| guards often limit the functionality of the table saw by enough
| that everyone just removes them, but even good guards are not
| perfect). Only after the above would I look at stopping the
| system when a problem is detected. Last, but only if all of the
| above fails - is you put warning stickers on.
|
| Let me emphasize: you should run the above list in order. If
| you can design a problem out then you are not allowed to put
| guards, brakes, or warning stickers on./
|
| Most industrial machinery is designed with the above process.
| there is a lot of machinery from early days still around with
| out safety, but most industry has been adding guards and brakes
| to those were possible and replacing (machines from the 1950s
| are probably worn out anyway) the old stuff. Industry also has
| extensive safety training for the dangers they they cannot
| prevent other ways. The safety results for industry is much
| better than it was 100 years ago. Not perfect by any means, but
| much better and getting better [I was going to write every
| year, but random chance means some years there are more
| accidents than others despite the safety situation overall
| improving yearly]
| mikey_p wrote:
| An example might be railroads putting a derailer at the bottom
| of a hill to protect industry or businesses. The derailer is
| removed when servicing the line, but put back to protect the
| end of the line industry from run-away cars. Conclusion: they'd
| rather have run-away cars de-rail and have to recover them,
| then letting them damage a factory or business.
| bawolff wrote:
| What's the story on the patents? If it was invented in 1999,
| shouldn't they have expired in 2021?
| bluGill wrote:
| They refined the invention over the years. Some of the
| additions are very useful and those patents won't expire for a
| few more years.
| thebigman433 wrote:
| Not really related to the actual content of the post, but I use a
| Lumafield at work constantly and love it! The scan quality and
| software is amazing. Scanning electronics is so much fun, and so
| helpful!
| hettygreen wrote:
| I bought my sawstop shortly after my partner started working in
| the medical field, where they'd see saw related injuries or
| amputations come in weekly.
|
| Saw was expensive, yeah.. but they hold their value on the second
| hand market, if you ever even see them for sale.
|
| I had a cabinet maker over last week, after he noticed my sawstop
| he showed me his 2 partially missing fingers.
|
| The company also isn't playing games, the saw is beautiful and a
| lifetime purchase.
| stavros wrote:
| > they hold their value on the second hand market
|
| With the topic under discussion, this is an amazing pun.
| xattt wrote:
| No way of getting a five-finger discount on these.
| weinzierl wrote:
| Thanks to the author for not burying the lede. This is how an
| informative article should look like and it was a joy to read.
| beAbU wrote:
| It's Ironic that this is basically an ad. Lumafield is an
| industrial CT scan provider, and these articles serve as an
| advertisement of their capabilities.
|
| I think this is marketing done right. I am not in the CT scan
| industry, nor do I think I'll ever have the need for these
| services, yet I came out slightly more knowledgeable about the
| world around me after reading their article. Maybe one day I
| will have the need for commercial CT services, and Lumafield
| will be the first one to come to mind.
| orbital-decay wrote:
| Is it feasible to stop the blade in comparable time by reversing
| the motor?
| MaxikCZ wrote:
| My guess the stopping will happen in comparable time it takes
| to start it. So, no?
| orbital-decay wrote:
| Much faster if you send the peak current, though.
| beAbU wrote:
| The start-up current of large table saws are truly massive.
| As in multiples of it's nominal "peak" operating current.
|
| So to bring the blade to a complete standstill, in
| significantly less time than start-up, is probably not
| feasible, unless you have a massive bank of capacitors with
| stored energy so that you can dump all that current in the
| motor without burning your building's wiring. But that will
| probably vaporize the motor.
| raverbashing wrote:
| No, these motors usually have a very slow spin-up time
| (probably an induction or a DC brushed motor)
|
| So even if you send peak current it won't (this is for the DC
| brushed, for the induction it can't be reversed unless you have
| a speed controller - also called an inverter)
| rocqua wrote:
| Generally you want to oull the blade down, more than you want
| to stop it. Get it away from the finger, rather than stop it so
| a finger can push into it safely.
| grues-dinner wrote:
| A basic consideration of the energy involved should tell you.
|
| 355mm radius disc, mass 1kg, moment of inertia is 1/2 mr2, so
| 0.06 kg.m2 [1]. This ignores all inertia of the arbor and motor
| rotor, mind, which is possibly significant (smaller radius but
| dense, depends on the transmission whether the motor is part of
| the blade system - if there's a clutch or belt to let go, then
| the motor isn't really part of the problem, but it's also not
| going to be part of the solution), Say it spins at 4000rpm, or
| 420 rad/s (some saws go to 6000 plus and this is quadratic).
|
| So kinetic energy in the blade alone is 1/2Iw2, or 0.5 * 0.06 *
| 4202, or 5.2kJ. For comparison, a rifle bullet is about half
| that, which seems right ballpark on the face of it.
|
| So to remove that energy in 5ms (SawStop's claim) is 1MW, or a
| current of 4000A at 240V, or 8000A at 120V. I don't know if any
| big saws run on that voltage in the US (may small ones?), but
| let's take the lower rest-of-world figure anyway. That's
| roughly 1300HP or 4 top-spec Tesla Model Y's at full throttle
| (320kW each).
|
| This is not completely technically impossible to deliver - you
| need about 400 0.1 farad capacitors charged to 250V, which are
| 100mm in diameter and 250mm tall and around $150 each, so a
| fridge-sized box, maybe two[2]. Some very large and pricy solid
| state switches will be needed too, and some nice copper busbars
| to get the current where you need it. Actually pushing 4000A
| into a motor winding for 5ms isn't that easy either as it's a
| canonical example of an inductive load, so you need even more
| current, plus hopefully a way to stop the current when done
| before turning the inside of the motor into a plasma ball.
| Evaporating the motor winding before you've stopped the blade
| is no good, and it'll be nice to use the saw again, so you'll
| need to uprate the coils _massively_ , which will make the
| motor very heavy, very large and very expensive.
|
| There are probably other issues like induced voltages far
| higher than main voltage the will need management. As mentioned
| earlier, you will also not be able to use, say, a belt drive -
| the motor needs a _very_ stiff physical connection to the
| blade.
|
| So, you won't break physics to do this, but it will be large,
| heavy and incredibly expensive. $50k in caps alone.
|
| Flipping the blade physically away from the obstacle is a much
| better bet. Which is actually SawStop's real trick - all that
| kinetic energy in the spinning blade system is grabbed and
| harvested to move those kilos of steel down and away in a few
| milliseconds. Stopping the blade is just a handy side effect of
| stealing all the energy. You could possibly do the same with an
| electrical system, but it would still be very large and very
| heavy compared to using the exact same huge kinetic battery
| that will always be there (or it's not a table saw) and which
| is actually the threat to safety in the first place.
|
| It's actually quite interesting to see the relative weakness of
| electrical forces illustrated this way. Even quite prosaic
| mechanical objects can develop powers that require electrical
| systems the sizes of small rooms to rival. And again, chemical
| systems contain more power still: all that spinning mass is the
| energy contained in a few grams of gunpowder.
|
| [1] Edit: I double counted a factor of 1/2 in the MoI - it's
| actually more then I first estimated!
|
| [2] Another underestimate as you really need a lot more as you
| have to get that energy out fast and you can't wait for the
| slow tail of the discharge curve to finish. Plus at least
| Nichicon only seem to go to 160V for 0.1uF!
| rewsiffer wrote:
| Meta comment: I really appreciate comments like this that
| breakdown problems to the first-principles physics and show
| their works. Thanks!
| grues-dinner wrote:
| Full disclosure, I now think I badly messed up the
| capacitor energy calculation perhaps while recasting it
| from a battery system to a capacitor system. You probably
| don't need _nearly_ that many just to store the energy
| usefully. But I estimate the other factors, like the
| discharge curves needing you to over build to get enough
| energy into the first 5ms, balance it out at to something
| vaguely fridge-sized anyway.
| scrumper wrote:
| Great comment, which incidentally serves to illustrate just
| how much energy you can store in a flywheel.
| Freak_NL wrote:
| The question that bothers me whenever SawStop comes up: why does
| it appears as if this isn't much of a thing outside of the US?
|
| Or is it and I'm just not seeing it from my Dutch viewpoint?
|
| Does anyone know of anyone who has written about this discrepancy
| with some numbers (emergency room admissions, SawStop sales)
| backing it?
| moooo99 wrote:
| > why does it appears as if this isn't much of a thing outside
| of the US?
|
| Patents. SawStop does not sell outside the US/NA to my
| knowledge and they hold all the patents required.
|
| In 2015 Bosch introduced a system that did essentially the same
| thing as SawStop, but with a slightly different mechanism.
| SawStop sued in the US and won against Bosch.
|
| Since 2017 SawStop is part of Festool, which explains why their
| tech is slowly making their way into Festool products. For
| example, the TKS 80 has the SawStop functionality built in. But
| at an MSRP of ~2.500EUR it's not really a hobbyist machine.
| rusteh1 wrote:
| Not true. They are widely available and used in Australia.
| zitsarethecure wrote:
| Bosch REAXX has a significant advantage, that being it is
| non-destructive to the saw blade when it activates. All you
| have to do is press a reset button and you are back to work.
| Not having the option of buying this tech instead of
| SawStop's in the US was a net negative for consumers, IMO.
| Blackthorn wrote:
| > Patents. SawStop does not sell outside the US/NA to my
| knowledge and they hold all the patents required.
|
| I think it's more regulatory. There are regulations in the EU
| around things like blade stop time that products designed for
| the USA do not meet.
| jwr wrote:
| One reason could also be that the US woodworking culture treats
| a table saw as an essential tool (especially the basic table
| saw, without a sliding table), while elsewhere track saws are
| used more, it seems.
|
| If you run commercial production, then you do need a table saw
| (but one with a sliding table!), but for hobby work you might
| as well spend some time for track saw setups and be much safer.
| ragingroosevelt wrote:
| I think you're probably right.
|
| I have an older Delta table saw and recently decided to sell
| it because a miter saw + track saw + some other tools you
| need anyhow does nearly everything a table saw would do, but
| uses space way more efficiently.
| delichon wrote:
| My table saw is space efficient because I also use it
| (covered) as a table in the middle of my small shop,
| sometimes to support work I cut with a track saw. And I
| added a router table to the extension, which just
| disappears as part of the table. It's a space dense with
| utility.
| miunau wrote:
| Table saws are very common in Europe in hobby circles as
| well. If you take woodworking in school you'll learn to use
| it along with other tools. Also, you usually build the
| sliding table and other jigs yourself using the tracks on
| every table saw. They're called T-tracks, there's a couple
| different common widths.
| Arainach wrote:
| They're very different tools, and neither is inherently safe.
| You can absolutely have kickback-like issues with a track saw
| if you're not careful when making plunge cuts, for instance.
|
| A track saw is more convenient and arguably safer when
| breaking down a huge piece of plywood. After that it's no
| table saw replacement. You can't easily do repeated cuts of
| identical stuff width, you can't work on small parts, you
| can't make most of the common jigs, you can't do dadoes or
| box joints, etc.
| miunau wrote:
| Sawstop wasn't available for purchase in the EU until last
| month. The only version that was available was the very
| expensive Festool table saw, though they are both from the same
| company. I'm currently waiting on my compact Sawstop to be
| shipped from the first batch.
| michaelt wrote:
| _> why does it appears as if this isn 't much of a thing
| outside of the US?_
|
| American hobby woodworkers all have huge two- or three-car
| garages giving them the room needed to store and use gigantic
| machines like table saws. Such large homes are unusual in
| Europe, and mostly owned by people who don't work with their
| hands.
|
| European hobby woodworkers don't lose their fingers to table
| saws because they're using circular saws instead.
|
| I suspect America also has a lot more woodworkers; many of
| their buildings have wood frames, wood siding, and bitumen-
| over-wood roofs.
| bluGill wrote:
| Homes as large exist all over Europe. Get into the cities
| where most people live and apartments don't have enough
| space, but just outside there are plenty of people with large
| houses. (they often have tiny garages though which doesn't
| leave enough space for a saw like this) In the US people live
| in apartments without enough space for a table saw as well,
| but houses with large garages are common (apartments often
| have garages, but they are too small for these saws and
| usually lack power). In my experience apartments in Europe
| are bigger than in the US but I've haven't seen enough
| apartments in Europe to be confident in that.
| nothercastle wrote:
| How is availability and cost is raw lumber in Europe?
| Freak_NL wrote:
| Good and fairly high, respectively. That doesn't stop
| people from woodworking though.
| dynm wrote:
| Americans on average have much more living space than
| Europeans: https://www.researchgate.net/figure/Average-
| floor-area-per-c...
| bluGill wrote:
| Average is not a good measure - more people in the US
| live in larger single family houses than in Europe.
| However those in Europe who live in single family houses
| have about as much space.
| michaelt wrote:
| I'm not talking about apartments, I'm talking about single
| family homes.
|
| If you look at the Google Maps marker for New York and go
| 90 minutes drive north, you get this:
| https://maps.app.goo.gl/RY9ebS6vcD5w8cQA6
|
| San Francisco and go 90 minutes north:
| https://maps.app.goo.gl/wJQx9BV5C2d7C6iR9
|
| You look up Berlin and go 90 minutes north:
| https://maps.app.goo.gl/7javF29PE1p6F4rb9
|
| Look up Paris and go 90 minutes north:
| https://maps.app.goo.gl/nyHut9xD4eAZnhdn9
|
| You look up London and go 90 minutes north:
| https://maps.app.goo.gl/VnEWsmNHSC5pc9H98
|
| Europe's higher population density gives them has great,
| walkable cities, practical public transport, good cycle-
| ability and plentiful bus stops.
|
| The trade-off is smaller homes and less parking. There's a
| reason nobody over there drives an F-150 truck.
| bluGill wrote:
| The space between houses is smaller, and the houses have
| much smaller garages. However the house themselves are
| similar size.
| michaelt wrote:
| _> the houses have much smaller garages_
|
| Yes, this is what I mean when I say few Europeans have
| the two- or three-car garages needed for a table saw to
| be practical.
| Macha wrote:
| They really aren't. My house is a 1250 sq ft 4 bedroom
| house. It gets comments from friends and family for being
| relatively large for a 4 br here, since the norm is 1000
| sq ft for a 4 bedroom. Similar style houses in the US
| seem to be about 2000 sq ft from a property search.
| elzbardico wrote:
| Yes, even in a lot of south american countries, for a
| upper middle class perspective, 1000 sq ft for a four
| bedroom house is a bit on the small side.
| kube-system wrote:
| In the US, a 1200 sq ft or smaller home would be a post
| ww2 "starter home", usually 2 or 3 bedroom. Homes of this
| size are pretty much not being built anymore, the average
| size of a new home in the US has been around 2500 sq ft
| for decades now. The median size of all existing homes in
| the US sits just north of 2000 sq ft.
| bobsyourbuncle wrote:
| Why are circular saws less prone to injury?
| jonstewart wrote:
| At least one hand is operating a circular saw and there's
| often a spring loaded guard that snaps into place when the
| saw isn't sawing. I'm sure plenty of people hurt themselves
| with circular saws, but as more of a hands-on tool you are
| very aware when using it. It is not nearly as precise or
| easy to use with large jobs as a table saw, however.
| michaelt wrote:
| I don't claim they are (or aren't, I don't know either way)
|
| I'm just saying you don't have tablesaw injuries if you
| don't have tablesaws.
| sowbug wrote:
| On a circular saw, the hand in motion maneuvers the cutting
| tool. On a table saw, it pushes the thing being cut. Either
| saw's blade sometimes grabs the material and kicks it back.
| If your hand is on that material, it can also be sent in an
| unexpected direction.
|
| (This is just one scenario. Both tools are capable of
| unwanted removal of body parts.)
| Blackthorn wrote:
| Lot of replies here but none of them have really hit the mark.
| European table saws are fundamentally different than American
| table saws, where the entire section left of the blade slides
| forward. Culturally it seems Europeans believe this is "safer"
| than the American style and therefore they don't need the blade
| safety mechanism. Personally I think that's nonsense, and
| apparently so do some of the companies because they've
| developed their own mechanism that they only use on their
| priciest saws.
|
| Woodworking YouTube has changed this a bit. Since American
| creators are so widespread, everyone has gotten exposed to
| SawStop and I know at least a couple years back people were
| trying to import American-style table saws instead of the local
| European-style because that's what YTers have. I don't know if
| it was regulatory or what that has prevented the former from
| being more available in Europe.
| rtkwe wrote:
| Interesting seems like the European version is essentially an
| integral sled? That does seem much safer and inherently keeps
| hands away from the blade when used properly so a saw stop
| mechanism might not actually add a huge amount of safety real
| safety but is still a nice final safety measure. A lot of US
| literature and videos I've seen are heavily suggests using a
| sled whenever practical.
| f1shy wrote:
| Also dados are prohibited (more or less) in the EU. So yes,
| there are regulatory issues. And btw, I just cannot find a
| sawstop to buy here (at a human price)
| rhinoceraptor wrote:
| I'm not sure if they still make it, but Festool and Sawstop
| are owned by the same parent company, Festool sells the
| TKS-80 saw in Europe that has the Sawstop tech.
| Freak_NL wrote:
| Right, dados are one of the things that baffle a lot of
| European woodworkers, myself included. Not that they don't
| seem useful; just a little on the iffy side of safety.
| mikey_p wrote:
| I believe they just don't market them there, probably not
| interested in confirming to all the different regulations for
| different markets, etc. I know some folks have imported them,
| but I don't think they are sold directly. I think Laura Kampf
| claims to have one of the first SawStops in Europe.
| RobotToaster wrote:
| Table saws are less common in Europe for hobbyists, also things
| like dado blades are effectively banned, which means we
| actually use the blade guards that come with saws. We tend to
| use routers for a lot of the things Americans will use a table
| saw for.
| jasode wrote:
| _> , I have an altendorf handguard sliding table saw, which will
| stop as fast as the sawstop, _
|
| The alternative approaches from other _industrial_ saw
| manufacturers that are "non-contact non-destructive" are
| interesting:
|
| - cameras and machine learning used by Altendorf "Hand Guard":
| https://www.altendorfgroup.com/en-us/machines/altendorf-hand...
|
| - inductive proximity (same science as Theremin[1]) used by
| Felder "PCS Preventative Contact System" : https://www.felder-
| group.com/en-us/pcs
|
| - SCM "Blade Off" (not sure of detection method ... looks like
| inductive proximity) :
| https://www.scmgroup.com/en_US/scmwood/products/joinery-mach...
|
| But I've heard reports from 3rd-parties that Altendorf's camera
| detection method is unreliable/glitchy and doesn't work as well
| as Felder's system. Maybe Altendorf fixed the bugs.
|
| Also, Altendorf's philosophy of using cameras & ML instead of
| inductive proximity reminds me of Tesla's philosophy using
| cameras instead of LIDAR (Waymo).
|
| [1] https://en.wikipedia.org/wiki/Theremin
|
| EDIT ADD: _> I'm not sure how comparable these alternatives are
| when two of them are "request a quote" kind of pricing, and the
| Altendorf is $7000+_
|
| My comment was about "industrial saws" so they're definitely not
| realistic alternatives to buying a jobsite SawStop for
| homeowners. I added italics to the adjective "industrial" to
| clarify this.
| miunau wrote:
| I'm not sure how comparable these alternatives are when two of
| them are "request a quote" kind of pricing, and the Altendorf
| is $7000+, unless you're considering an entire cabinet. None of
| them will go on a job site with you, for example. I would love
| to test the Felder system though.
| Blackthorn wrote:
| Yeah, they aren't comparable in the least. These companies
| use it for market segmentation. You'll only get this on the
| ridiculously expensive table saws. Whereas a Sawstop _cabinet
| saw_ (the industrial one!), still expensive for an American-
| style table saw, is a fraction of the price. In the case of
| Felder, 10% the price!
| kurthr wrote:
| Totally agree, and wouldn't really comment on it except to
| say that the cheapest Sawstop is $1-3k even on blackfriday.
| That's not really in the same league as other jobsite saws
| that are $100-300.
|
| Each one really is a ~10x step in cost above the other. Of
| course quality and safety/reliability are higher too, and I
| know which I'd buy. But, comparable only sort-of.
| andrewaylett wrote:
| Sub-$1k list price now, with
| https://www.sawstop.com/product/compact-table-saw/ being
| $899.
|
| Still a pretty fair assessment, though.
| horsawlarway wrote:
| Sawstop is really only about 2-3x the price of an
| equivalent saw. It's not 10x more.
|
| The 100/200 dollar table saws are not really comparable
| (at a basic spec level, they're just not the same thing -
| 8" blades, smaller table, no fence)
|
| Most reasonable products you would actually buy for a
| jobsite are in the $500 range. The same Sawstop is 1500.
| The cheap no-stand versions are $300. The same Sawstop is
| 900. Pretty sure they're targeting 3x as the price.
| dylan604 wrote:
| There's no way I'm trusting the safety of my fingers to
| today's ML abilities reading a live camera feed.
| rahkiin wrote:
| If you don't have this extra feature, all your safety
| depends on you. That still is the case.
| kube-system wrote:
| People exhibit different behaviors of risk taking when
| they know there are safety systems in place to protect
| them.
| dylan604 wrote:
| Never mind the extra money spent on a "safe" saw vs the
| one without.
| zdragnar wrote:
| That depends on how they fail. If they trigger on false
| positives, that's money wasted on lost time and damaged
| equipment.
|
| On the flip side, if they fail a real case, it may well
| be because they engendered a false sense of safety, a bit
| like a sharp knife being safer than a dull one.
| dylan604 wrote:
| Do you work for Tesla FSD? That's exactly their stance.
| If I'm still dependent, then it doesn't do what it says
| on the tin. I want my money back.
| FridgeSeal wrote:
| "Pay money for this feature"
|
| "Ok, here's your money"
|
| "By the way, to use the feature, you actually just do it
| yourself and then pretend the product did it"
| formerly_proven wrote:
| I don't see the point of a Sawstop-type system for an
| Altendorf-style panel saw. The whole point of that saw design
| is that your hands are nowhere near the blade!
| lupusreal wrote:
| > _Also, Altendorf 's philosophy of using cameras & ML instead
| of inductive proximity reminds me of Tesla's philosophy using
| cameras instead of LIDAR (Waymo)._
|
| Kind of seems like the opposite. I could be wrong, but _in the
| case of the saw_ the cameras /AI are probably more expensive to
| develop and deploy than the inductive sensing. With the cars
| though, it's the cheaper option for sure.
| ejs wrote:
| I love my sawstop, it's a great machine.
|
| Often times when a product has some patent-protected feature, the
| product itself is substandard, but I have not found that case
| with sawstop. It's one of my highest quality tools.
|
| It would be nice if the mechanism wasn't so destructive. I
| accidentally had an aluminum fence just a fraction of a mm too
| close, and it touched the blade. I was using a dado stack, and it
| did a number on the carbide teeth of the blades. Good dado sets
| are not cheap, nor is the sawstop cartridge.
| hyperbovine wrote:
| I'm struggling to imagine a scenario where dadoing <1mm from
| the fence was a good idea in the first place. I'm assuming
| you're talking about a miter/crosscut fence but still...
| icey wrote:
| Cutting a rabbet? Probably should have used a sacrificial
| fence, but it's easy to see how this could happen.
| mikey_p wrote:
| Could be an aluminum extrusion or something in a miter gauge
| or cross-cut sled.
| mturmon wrote:
| I've stopped myself just in time from triggering my Sawstop
| while using an aluminum miter gauge.
|
| The scenario is that the gauge was set with reasonable (1cm)
| clearance at one angle, and then I changed the angle without
| re-checking the clearance, and the back side of the fence
| swiveled into the blade path. Pythagorean fail.
|
| Or, perhaps with GP comment, used a setup with reasonable
| clearance for a regular blade, and then put in a wider dado,
| which ate into the clearance.
| ejs wrote:
| I had a sacrificial fence (wood) on the aluminum fence to
| reduce blowout. I had the aluminum extend to near the blade
| to reduce the deflection of the whole thing. It was too
| close.
|
| Really, I should have sacrificed a crosscut sled for dado
| usage, but it really chews them up.
| efsavage wrote:
| +1, I've had mine for 5+ years and it is still genuinely a joy
| to use. I went with the "buy your last tool first" approach and
| splurged on a 5HP ICS and don't regret a single penny spent on
| it.
| thedman9052 wrote:
| We had a saw with a mechanism that was non destructive and
| SawStop sued them out of the country (Bosch REAXX). It's why my
| feelings on SawStop are complicated, they say they're all about
| safety and willing to work with others but stomped out the only
| one that tried.
| hajile wrote:
| Bosch REAX used compressed air cylinders to drop the blade
| without damaging it. They got sued into oblivion by SawStop
| because SawStop was somehow granted a patent on the idea of
| stopping a blade quickly. As a side fact, the Bosch sensor
| electronics weren't done properly and could sometimes be
| affected by BlueTooth.
|
| The whole "releasing our patent" is simply SawStop's way of
| trying to lock out the competition. All their competitors
| (including Bosch) have said that it will take several years
| before they could develop an alternative product leaving them
| in violation.
|
| Finally, the regulation SawStop is trying to force doesn't even
| solve the injury problems for a few reasons.
|
| The biggest is that CPSC does NOT affect commercial saws. As it
| turns out, hobbyists don't have as many injuries as you might
| think because they don't use their saws all the time and they
| have a very healthy respect for them (there are exceptions of
| course). Most serious injuries happen because the guy at the
| commercial shop has become too complacent and made a mistake
| after a long day at work. This ruling does nothing to change
| that situation.
|
| You also can't fix stupid. If blade guards and riving knives
| are left on saws, the chances of injury are incredibly low, but
| people choose to remove one or both of these. They'll also turn
| off the safety features and do something they shouldn't.
| SawStop safety is over-represented because the people who spend
| the extra money for one are already predisposed to take safety
| seriously.
|
| This leads to the price issue. Table saw prices will go up from
| $220 up to a minimum of $600 or more. This increases the risk
| of someone not having that much money and then turning their
| circular saw upside down making an incredibly dangerous table
| saw without a blade guard, riving knife, or even a parallel
| fence massively increasing the baseline risk for injury.
|
| I love the idea of SawStop and I think it's an amazing safety
| device, but after reading the arguments on all sides, I think
| we should leave the current saws situation alone and instead
| simply require each saw manufacturer to offer at least one AIM
| model in their product lineup by 2032 or so (while maybe
| getting the courts to fix up the colossal screwups they made
| with the SawStop patents). This will give them time to develop
| alternatives and maybe drive down prices over time until it
| finally (hopefully) makes economic sense to only sell AIM
| devices.
| aidenn0 wrote:
| My shop teacher seemed to think the band saw was more dangerous
| than the table saw. Was he wrong, or is it just that table saws
| are used so much more than band saws that they dominate the
| injuries?
| tstrimple wrote:
| Table saws are dramatically more dangerous than band saws. When
| a band saw blade makes contact with whatever it's cutting, the
| force is in a single direction. Down at the table which
| provides material support. Table saws use a rotating blade and
| often a fence system. Lots of things can go wrong there, but it
| typically involves binding between the fence and the blade
| which can lead to kickback which can send chunks of wood
| through a wall or potentially more dangerous is it can cause
| the wood to twist violently into the blade risking bringing
| your hand towards the blade.
|
| Here's a saw stop in action, so it's not gory. But look at how
| FAST things go wrong here and how violent the interaction was.
|
| https://www.reddit.com/r/Whatcouldgowrong/comments/11s53ew/w...
|
| Compare that to a band saw in use, and you can see fingers
| quite close to the to the cutting edge and still have good
| control over the work.
|
| https://www.youtube.com/watch?v=JlHe9gOphBw
| oplav wrote:
| I haven't used a bandsaw a lot, but I have seen some photos of
| gnarly lost fingers.
|
| I use a table saw quite a bit and think there are more ways
| things can go wrong, most of which stem from kickback which
| happens in a split second. The wood will either fly back and
| hit you, or your hand will be pulled into the blade and you
| will likely lose a finger.
|
| Both machines can be safe with the proper precautions. That
| said, I still enjoy my SawStop as insurance for my fingers
| since I still write software for my day job.
| tonyarkles wrote:
| > I use a table saw quite a bit and think there are more ways
| things can go wrong, most of which stem from kickback which
| happens in a split second. The wood will either fly back and
| hit you, or your hand will be pulled into the blade and you
| will likely lose a finger.
|
| One of the more horrifying things I've witnessed second-hand
| with kickback was a lucky third scenario. It was high school
| woodshop and one morning the teacher pulls us all over to the
| miter saw bench and points at a huge chunk that's missing
| from it. The bench surface was two or three layers of MDF
| glued and screwed together. He explained that someone had
| been cutting something on the table saw 8 feet away from it,
| had a kickback, the kickback missed but the piece of wood
| shot into the miter bench and that was the result. Thinking
| about what that same piece of wood would have done if it had
| hit a human... yeesh, I definitely treated kickback with a
| lot more respect after that day.
| dylan604 wrote:
| Ever seen someone bind the material in the table saw where the
| material kicks back into the operator? Here's just the first
| example from a quick search:
|
| https://www.youtube.com/watch?v=yuWNEAlC2-0
|
| Not something a band saw will do. So a band saw will just cut
| you while the table saw will cut you but also hurl material at
| you.
| efsavage wrote:
| They can both be dangerous but one difference is that the band
| saw _seems_ much less dangerous and people would take it less
| seriously. In a shop full of adolescent novices I could see
| this causing more injuries whereas the tablesaw is probably
| more closely supervised and people will respect it more.
|
| I'd say overall a tablesaw is more dangerous compared to a band
| saw because it has the additional failure mode of kickback
| which happens occasionally even to very experienced operators.
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