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CT Scans of New vs. Used SawStop

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Re: CT Scans of New vs. Used SawStop

#171

Post by dylan604 »

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?

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.

Re: CT Scans of New vs. Used SawStop

#172

Post by grues-dinner »

rewsiffer wrote: post #166
grues-dinner wrote: post #82

Earlier quoted context omitted.

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…

Meta comment: I really appreciate comments like this that breakdown problems to the first-principles physics and show their works. Thanks!

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.

Re: CT Scans of New vs. Used SawStop

#173

Post by efsavage »

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 kickback which happens occasionally even to very experienced operators.

Re: CT Scans of New vs. Used SawStop

#174

Post by tonyarkles »

oplav wrote: post #170
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?

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…

> 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.

Re: CT Scans of New vs. Used SawStop

#175

Post by efsavage »

ejs wrote: post #90

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 numbe…

+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.

Re: CT Scans of New vs. Used SawStop

#176

Post by thedman9052 »

ejs wrote: post #90

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 numbe…

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.

Re: CT Scans of New vs. Used SawStop

#177

Post by rahkiin »

dylan604 wrote: post #169
miunau wrote: post #98

Earlier quoted context omitted.

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.

There's no way I'm trusting the safety of my fingers to today's ML abilities reading a live camera feed.

If you don’t have this extra feature, all your safety depends on you. That still is the case.

Re: CT Scans of New vs. Used SawStop

#178

Post by rhinoceraptor »

f1shy wrote: post #150
Blackthorn wrote: post #142

Earlier quoted context omitted.

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…

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)

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.

Re: CT Scans of New vs. Used SawStop

#179

Post by kube-system »

rahkiin wrote: post #177
dylan604 wrote: post #169

Earlier quoted context omitted.

There's no way I'm trusting the safety of my fingers to today's ML abilities reading a live camera feed.

If you don’t have this extra feature, all your safety depends on you. That still is the case.

People exhibit different behaviors of risk taking when they know there are safety systems in place to protect them.

Re: CT Scans of New vs. Used SawStop

#180

Post by zdragnar »

rahkiin wrote: post #177
dylan604 wrote: post #169

Earlier quoted context omitted.

There's no way I'm trusting the safety of my fingers to today's ML abilities reading a live camera feed.

If you don’t have this extra feature, all your safety depends on you. That still is the case.

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.

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