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CT Scans of New vs. Used SawStop

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Re: CT Scans of New vs. Used SawStop

#61

Post by inferiorhuman »

jchw wrote: post #56
bradly wrote: post #54

Earlier quoted context omitted.

> 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.

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, the…

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.

Re: CT Scans of New vs. Used SawStop

#62

Post by mym1990 »

Implicated wrote: post #58
bradly wrote: post #55

Earlier quoted context omitted.

> 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.

What sort of cuts would cause you to need to remove the riving knife?

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.

Re: CT Scans of New vs. Used SawStop

#63

Post by morcheeba »

davesmylie wrote: post #35
dyauspitr wrote: post #29

Earlier quoted context omitted.

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?

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 di…

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.

Re: CT Scans of New vs. Used SawStop

#64

Post by hettygreen »

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.

Re: CT Scans of New vs. Used SawStop

#65

Post by ckozlowski »

bradly wrote: post #55
GuB-42 wrote: post #34

Earlier quoted context omitted.

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 featur…

> 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.

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

Re: CT Scans of New vs. Used SawStop

#66

Post by cyberax »

davesmylie wrote: post #35
dyauspitr wrote: post #29

Earlier quoted context omitted.

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?

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 di…

> 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.

Re: CT Scans of New vs. Used SawStop

#67

Post by ckozlowski »

WillAdams wrote: post #2

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 inj…

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.

Re: CT Scans of New vs. Used SawStop

#68

Post by lukaslalinsky »

mym1990 wrote: post #62
Implicated wrote: post #58

Earlier quoted context omitted.

What sort of cuts would cause you to need to remove the riving knife?

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.

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.

Re: CT Scans of New vs. Used SawStop

#70

Post by AlotOfReading »

ckozlowski wrote: post #65
bradly wrote: post #55

Earlier quoted context omitted.

> 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.

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

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.
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