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CT Scans of New vs. Used SawStop

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Re: CT Scans of New vs. Used SawStop

#191

Post by scrumper »

grues-dinner wrote: post #82
orbital-decay wrote: post #71

Is it feasible to stop the blade in comparable time by reversing the motor?

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…

Great comment, which incidentally serves to illustrate just how much energy you can store in a flywheel.

Re: CT Scans of New vs. Used SawStop

#192

Post by Slyfox33 »

WillAdams wrote: post #101
wat10000 wrote: post #9

Earlier quoted context omitted.

Are you suggesting that injuries don’t count if the operator’s actions contributed to them and they’re not worth preventing?

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.

"Just don't make mistakes!"

Re: CT Scans of New vs. Used SawStop

#193

Post by horsawlarway »

kurthr wrote: post #167
Blackthorn wrote: post #141

Earlier quoted context omitted.

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!

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.

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.

Re: CT Scans of New vs. Used SawStop

#194

Post by kiney »

Blackthorn wrote: post #142
Freak_NL wrote: post #83

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?

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 t…

the "american" style was literally imvented by a german company

Re: CT Scans of New vs. Used SawStop

#195

Post by dsunds »

bsder wrote: post #60
dyauspitr wrote: post #31

Earlier quoted context omitted.

That’s terrible though. You can’t make knife manufacturers responsible for everything a knife does.

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 f…

Radial arm saws vanished because they were a compromise solution that slider miters made inferior. They are pretty safe as the blade is constrained to travel along the arm for cross cuts and for rips is locked in place. The usual problem is simply stalling the saw. Rip cuts can definitely kick back if you don’t take the time to set them up right including the guard and anti kickback device. They can do it all, cross cut, compound miter, rip, dado. There were some sketchy shaping attachments I’d be hesitant to use. But the main problem is they are large as a big table saw and the changeover time. A table saw and sliding miter is the way to go now. But I still own a radial and if I had the space in my shop would set it up Norm Abram style.

Re: CT Scans of New vs. Used SawStop

#196

Post by mlyle »

bigstrat2003 wrote: post #152
mlyle wrote: post #6

Earlier quoted context omitted.

> 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. Howev…

> 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 safe…

> 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.

You don't need to prevent too many maimings to pay for a whole lot of these and their occasional consumables.

Sure, risk homeostasis will claw some of the benefit back, too.

Re: CT Scans of New vs. Used SawStop

#197

Post by danielheath »

stavros wrote: post #110
danielheath wrote: post #109

Earlier quoted context omitted.

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.

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.

The world has a _lot_ of guys with seven fingers who used to believe they would never be so careless.

Re: CT Scans of New vs. Used SawStop

#198

Post by aidenn0 »

efsavage wrote: post #173
aidenn0 wrote: post #163

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?

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 kick…

I think that's probably it. The band-saw didn't really look different or more intimidating than the jigsaws we had previously been using. The table-saw looks like it wants to kill you.

Re: CT Scans of New vs. Used SawStop

#199

Post by inferiorhuman »

harrall wrote: post #76
inferiorhuman wrote: post #61

Earlier quoted context omitted.

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.

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 bla…

Perhaps it's a bathtub curve, but dollars to donuts you'll have an easier time convincing a newbie to not do dangerous shit than someone more experienced. Beyond just doing stupid shit (plunge cuts, circles, arguably dados, whatever) there's professional pressure. Take a look at the whole stone countertop industry (very) slowly coming to terms with silicosis.

Either way I think Sawstop is great. As a hobbyist I wish it were cheaper. Although to be fair a big part of the cost is that Sawstop doesn't sell low end saws — that's nothing to do with the safety tech.

Re: CT Scans of New vs. Used SawStop

#200

Post by jwr »

Arainach wrote: post #119
jwr wrote: post #89

Earlier quoted context omitted.

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.

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'…

I regularly do repeated cuts of identical stuff width with my tracksaw, so I'm not sure why you'd think you can't easily do that.

About the only thing the tracksaw is not good for are long cuts of narrow stock. And yes, dadoes, but I do those with a router and arguably you should not even try to do them with a table saw, unless you are trying to hurt yourself.

Implying that because of the possibility of kickback a tracksaw is comparably dangerous to a track saw makes no sense.

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