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).
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.
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.
> 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.
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!
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.
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.
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.
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...
+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.
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.
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.
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.
> 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.
> 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.
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.
> 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 ~2.500€ it’s not really a hobbyist machine.
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.
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.
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.
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.
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.
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.
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.
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?
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.
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.
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.
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:
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!
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)
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.
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!
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 .
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.
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]
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.
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.)
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.
> 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.
> 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.
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.
> 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.
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.
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.
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.
> 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.
jasode|1 year ago
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|1 year ago
lupusreal|1 year ago
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.
formerly_proven|1 year ago
ejs|1 year ago
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.
thedman9052|1 year ago
hajile|1 year ago
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.
hyperbovine|1 year ago
efsavage|1 year ago
thelastparadise|1 year ago
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fasthands9|1 year ago
DannyBee|1 year ago
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.
voisin|1 year ago
fastball|1 year ago
> 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.
Freak_NL|1 year ago
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?
michaelt|1 year ago
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.
Blackthorn|1 year ago
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.
moooo99|1 year ago
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 ~2.500€ it’s not really a hobbyist machine.
jwr|1 year ago
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.
miunau|1 year ago
RobotToaster|1 year ago
mikey_p|1 year ago
unknown|1 year ago
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andrewflnr|1 year ago
zo1|1 year ago
bawolff|1 year ago
bluGill|1 year ago
weinzierl|1 year ago
beAbU|1 year ago
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.
hettygreen|1 year ago
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|1 year ago
With the topic under discussion, this is an amazing pun.
aidenn0|1 year ago
tstrimple|1 year ago
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|1 year ago
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.
efsavage|1 year ago
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.
dylan604|1 year ago
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.
orbital-decay|1 year ago
grues-dinner|1 year ago
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!
MaxikCZ|1 year ago
raverbashing|1 year ago
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|1 year ago
thebigman433|1 year ago
chewbacha|1 year ago
shrubble|1 year ago
davesmylie|1 year ago
One of them did require a resharpen though.
smoyer|1 year ago
isatty|1 year ago
GiorgioG|1 year ago
jdprgm|1 year ago
bluGill|1 year ago
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|1 year ago
jchw|1 year ago
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|1 year ago
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.
bradly|1 year ago
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.
Hilift|1 year ago
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.
WillAdams|1 year ago
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.
RajT88|1 year ago
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.
Blackthorn|1 year ago
> 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.
unsnap_biceps|1 year ago
ckozlowski|1 year ago
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.
bagels|1 year ago
wat10000|1 year ago
onlypassingthru|1 year ago
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)
mlyle|1 year ago
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.
bsder|1 year ago
Simply make table saw manufacturers liable for any injury from the saw and this kind of mechanism will instantly become default.