SawStop, stops on contact with skin is coming to Europe soon!

[Eshmiel]

Most of the comments around this seem to be looking only from the pov of a home-hobbyist set up. In some professional environments, the arguments may be quite different. At present, I work on my own, but until recently had an apprentice and often at least one other guy working for me. There's times you have to run the saw without the guard or riving knife, its just a fact, and anyone who says not doesn't know what they are at.
But even with a guard, accidents still seem to happen, and HSE is going to find some way of it being the employer's fault. Doesn't matter if it was operator negligence or what, building work intrinsically carries risk of accident. I've known enough tradesmen who are carrying the effects of an injury, guys cleverer than me, but one day, something happened that had a consequence.
If one of my guys was injured, he's out the rest of the day, probably me too if I have to drive him to casualty. Two half days pay is going to cost me a few hundred quid- far more than the cost of a saw-stop crash.
Never mind the guilt and responsibility that someone is injured working for you, the mental cost of which cannot be calculated, there's a simple economic argument for this system- a saw-stop activation is less expensive than an injury.
And if a hobby guy wants the same peace of mind, why not? Those who are using wood machinery every day ought to be working safely through good habits. The occasional user is maybe more likely to have an issue due to lack of familiarity.

Good arguments, not to be refuted really. Well, perhaps except for that thing about it being necessary to remove the riving knife sometimes. An overcut not right through the workpiece justifies taking a guard off but why the riving knife? Although a hobbyist I've performed a large variety of TS operations, probably thousands by now. I've never had to remove the riving knife.

Incidentally, the Sawstop mech does nothing to prevent kickback. That requires the riving knife, a properly set up fence and all of the other tech and procedures to avoid kickbacks. But you must know this better than me, eh?

 

[Eshmiel]

I guess you could argue that the destructive way SawStop works could be looked at as a positive thing.

Trigger the SawStop and it could potentially cost £200 for a new blade and brake cartridge and maybe even a couple of days without a saw if you don't have a spare cartridge on stock.

Trigger the Altendorf and you are back working within a few seconds and zero cost.

I'm pretty sure I know which one will encourage safer working practice.

On a video I watched recently a furniture maker said he covers the cameras on the Altendorf with masking tape when he needs to put his fingers close to the blade..........

The Altendorf traffic light system will surely act as an educator of users about safe, near-dangerous and dangerous hand positions. The Sawstop has to be triggered for the user to notice that lesson.

The Altendorf has a built-in facility for switching the safety device off, although there's a lot of surrounding info about when this is justified and when its not. No need to tape up cameras.

 

[Bingy man]

Do you see criticism of a saw tech as somehow sneering at those who buy one? This is not the case and only suggests that the notion that "I am what I own" is valid. This will please the sellers, of course, but its is never true.

Did I say ".... all drivers...."? No, just some drivers. Risk compensation is a very well documented effect of all safety tech. It doesn't apply to everyone who uses it but it can be very seductive to the notion that, "This makes me safe so I can take as many risks as I like". Not everyone is susceptible but an awful lot are, including me in past times. Nor is it the only cause of taking far too great a risk when using any tech. There are numerous other causes too. Nor are such safety devices useless, as they are successfully used within their limits by many to actually reduce risks.

**********
In this day and age it’s not uncommon to witness a fanboy mentality in operation (part of the "I am what I own" syndrome). Criticism of a device is taken as an insult by owners. This is silly.

All im saying is not everyone who has had a serious injury from a powertool is ignoring the usual and necessary safety precautions and performing dangerous practices. If you are unfortunate to have a car accident it does not necessarily mean your an unsafe driver , likewise buying a saw stop does not mean you are going to suddenly start to perform death defying practices with your table saw , your initial post seamed to suggest that saw stop was for such people and that if you use push sticks, feather boards etc that you don’t need one . Others here have made similar statements implying if you need such a device you should not be using a tablesaw in the 1st place. but there is always the ( “ what if “ ) moment .. I’ve personally been using powertools since I was 12/13 . I’ve had 1 accident in all these years and that was with a 9” angle grinder - I broke all the safety rules as I just wanted to confirm it was working-it was but it kicked out of my hands and landed on my foot while still running. Fairly minor injury but it could of easily so much worse .That was over 20 years ago and I’m 60 this year .. back to s/s I don’t like the fact it destroys the blade and the cartridge but a couple of hundred ££s compared to my hands and no one else’s is in my own opinion a worthy cost . It would not change my normal safe way of working . Unfortunately there are always going to be these type of people eg i don’t need to drive at the speed limit ( not a target ) because im protected by my air bags , my abs brakes , seatbelts etc , I won’t get hurt using my table saw as it has flesh sensing technology, this rattlesnake can’t kill me because there is anti venom , I can leap of this 600 ft high bridge because this bit of elastic rope will keep me safe ….. thankfully like yourself and the vast majority of ukw members I’m not one of these types but I would definitely consider a saw stop. It’s just another level of safety to be used with all the other methods and practices of safe working ..

 

[Ross Buchanan]

Good arguments, not to be refuted really. Well, perhaps except for that thing about it being necessary to remove the riving knife sometimes. An overcut not right through the workpiece justifies taking a guard off but why the riving knife? Although a hobbyist I've performed a large variety of TS operations, probably thousands by now. I've never had to remove the riving knife.

Incidentally, the Sawstop mech does nothing to prevent kickback. That requires the riving knife, a properly set up fence and all of the other tech and procedures to avoid kickbacks. But you must know this better than me, eh?

Most riving knives sit above the top of the blade in order to hold the crown guard. In such a case, and that is the case on the 3 site saws I have owned and on my slider, I would rather remove the riving knife and crown guard, and know I must replace them, than run with a modified riving knife that could not hold a crown guard.
If you need to cut a chamfer on the edge of a piece, and the blade tilts toward the fence- most cabinet saws/sliders are like this- you either pull the fence right back so it ends before the blade, or you remove the riving knife, clamp a sacrificial piece to the fence which goes past the rear edge of the blade. Then set the angle and raise the blade so it cuts a slot into the sacrificial fence. Then you can run your workpieces with the whole of the blade safely covered.
My justification, anyway. YMMV

 

[Mike Fletcher]

Perhaps my explanation of “imagine the cut” needs some clarification. I have been using tables saws of various configurations for close to 50 years and still have both hands and all ten fingers. “Imagine the cut” is one of many practices that I adhere to whether I’m performing rip cuts or crosscuts. Simply imagine where your fingers / hands will go if they slip off the timber. I won’t go into all the other things that I do, but one that is intended to prevent kickback is throw away the push sticks and make / use a push shoe. This allows you to apply downward pressure on the timber while pushing it through the blade and keeps your hands well away from the blade. If we are all aware of keeping both your hands one hand width away from the blade (when possible) then the unexpected slip is where keeping a finger or two over the top of the rip fence (if not using a push shoe) is a good idea. If your fingers / hand slips off the timber your hand will travel along the rip fence and not into the blade.

 

[Bingy man]

going off topic but I believe the point is relevant to my previous posts in this and other threads on the same subject ( safe working practices) including dynamic risk assessment )
Subject - b. Gas engineers asbestos awareness and relevant actions
During this mandatory course we were asked what we should do if we disturbed suspected asbestos in a customers property… answers followed by the engineers as a group included hoover it up ,,,phone the fire brigade , call your manager ,, call your t u union rep ,,, nothing as it’s probably not asbestos,,, spray it with water ,, etc etc . The manager hosting the session said spray it with water or cover it with damp newspaper and leave the property immediately. I had several issues with this . How much time will elapse while I search for a spray bottle fill it with water and spray the affected area ,,same with the wet paper,, also the spraying of the water could actually spread the suspected asbestos fibres as they are not easily visible. Then I questioned the ( leave the property immediately ) as finding the above paper / spray bottle was likely to take several minutes and I’m now potentially contaminated with asbestos fibres should this be now a full evacuation snd remove the customer and family members including pets ?? The answer given was just the engineer !!
I said that this can’t be correct as ive now left the customer and family in a suspected asbestos contaminated environment. The discussion that followed was a worse than the worst sharpening thread on ukw . So I left and went for a smoke and returned to the course . I went onto the stage and loudly announced that 15 mins ago I hypothetically accidentally disturbed suspected asbestos and did what the manager said and left the property immediately and as such everyone on this room is now potentially contaminated. Silence followed . I was told not to delay the course as it was not helpful. 60 mins later the advice was amended to include all the occupants of the property ( management had been frantically phoning their regional managers and were in mass panic )
So my point is I take my safety and the safety of those around seriously and if I’ve mis understood anyone’s point or comments then my apologies but I will always work safely and to the best of my knowledge and ability. I’ve personally used far more dangerous equipment than a t/saw or router as I imagine many of the ukw members have . A large backpack containing several litres of gramaxone ( paraquat ) is far more dangerous to life than power tools or machines ..

 

[Eshmiel]

So my point is I take my safety and the safety of those around seriously.....

Just so - but the difficulty is that its a very complex matter in many scenarios involving a danger and associated risks.

As your tale illustrates, any invention involving the use of a complex procedure to deal with a complex issue falls foul of The Law of Unintended Consequences. Every action generates not just desirable consequences (being safer from asbestos by yourself getting away from it) but also unintended and often deleterious consequences (leaving so fast there's no time to warn others).

Our modern trend is to take The Rationalist approach to such issues. We sit down and with our immaculate modern logic and up-to-the-minute reasoning we work out a policy and process to implement it. We concentrate on addressing the danger. We ignore previous practice as old-hat. We often fail to think about the additional effects of our new gleaming policy and procedure besides those in our focus. Sometimes the policy and process generate more dangers, sometimes worse dangers ..... and their effects.

Consider any political policy and the consequent processes. They're often disastrous in their unintended consequences.

The alternative mode used to be "tradition" - the slow and evolutionary process that develops practices that tend to achieve the desirable whilst evolving to avoid the undesirable. This takes a long time, often decades or even centuries, especially as surrounding conditions change and require adaptation of traditional practices to meet new factors. Traditions can also become ossified, since they often lack any rationalisation-manual in favour of a , "That's just how we always do it" approach.

*************

One of the ways that The Law of Unintended Consequences manifests is that risk compensation effect I keep going on about. Folk assume that a particular policy and process have solved a danger as they obviously have - but they fail to notice that the solution has not solved associated dangers; and may even have introduced new ones.

When we get a bit wiser about this, often via hard experiences and their savage lessons upon our person, we become more wary of the "At Last, The Final Solution" claims. So often, the Final Solution to danger A makes some new dangers B, C --- Z.

 

[Bingy man]

Just so - but the difficulty is that its a very complex matter in many scenarios involving a danger and associated risks.

As your tale illustrates, any invention involving the use of a complex procedure to deal with a complex issue falls foul of The Law of Unintended Consequences. Every action generates not just desirable consequences (being safer from asbestos by yourself getting away from it) but also unintended and often deleterious consequences (leaving so fast there's no time to warn others).

Our modern trend is to take The Rationalist approach to such issues. We sit down and with our immaculate modern logic and up-to-the-minute reasoning we work out a policy and process to implement it. We concentrate on addressing the danger. We ignore previous practice as old-hat. We often fail to think about the additional effects of our new gleaming policy and procedure besides those in our focus. Sometimes the policy and process generate more dangers, sometimes worse dangers ..... and their effects.

Consider any political policy and the consequent processes. They're often disastrous in their unintended consequences.

The alternative mode used to be "tradition" - the slow and evolutionary process that develops practices that tend to achieve the desirable whilst evolving to avoid the undesirable. This takes a long time, often decades or even centuries, especially as surrounding conditions change and require adaptation of traditional practices to meet new factors. Traditions can also become ossified, since they often lack any rationalisation-manual in favour of a , "That's just how we always do it" approach.

*************

One of the ways that The Law of Unintended Consequences manifests is that risk compensation effect I keep going on about. Folk assume that a particular policy and process have solved a danger as they obviously have - but they fail to notice that the solution has not solved associated dangers; and may even have introduced new ones.

When we get a bit wiser about this, often via hard experiences and their savage lessons upon our person, we become more wary of the "At Last, The Final Solution" claims. So often, the Final Solution to danger A makes some new dangers B, C --- Z.

What amazed me about safety awareness courses was that whoever designed it was only thinking of the engineer or to be more accurate the company . If I had not questioned it then it would have been implemented as standard procedure and that would have been integrated into what they called standard operating procedures. The whole point of it was to make engineers aware of asbestos and d what to do if it was disturbed accidentally but the scope of the course had completely missed the fact that this could potentially happen in a customer’s home or even a business or public building. No surprise it was scrapped and replaced with - asbestos awareness- the customer and you ( the engineer ) yet no credit was ever given to myself for raising this potentially dangerous approach to safety .. ironically 1 of my first ever ( unofficial jobs was working on a demolition of an old factory we here we went underground in old inspection/ access rooms cutting out the old steel heating pipes . The first job was to remove old insulation and bag it up . It was never tested so could well of been or contained asbestos

 

[Sideways]

Welcome back Jacob !

 

[Jacob]

Perhaps my explanation of “imagine the cut” needs some clarification. I have been using tables saws of various configurations for close to 50 years and still have both hands and all ten fingers. “Imagine the cut” is one of many practices that I adhere to whether I’m performing rip cuts or crosscuts. Simply imagine where your fingers / hands will go if they slip off the timber. I won’t go into all the other things that I do, but one that is intended to prevent kickback is throw away the push sticks and make / use a push shoe.

Push shoes (depending on the design) have two major disadvantages; you have reach over the workpiece to use it which shortens your reach overall, at the end of a pass your hand/arm passes directly over the exposed cutters. Push stick extends your reach and doesn't get as far as passing over the cutter.
I'm slightly mystified by kick-back, never seeming to have experienced it. Kick up on the other hand is prevented by a crown guard, or feather board on the fence, or by a push stick if you are holding it down

This allows you to apply downward pressure on the timber

I do this with push stick in left hand, and/or pressing in towards the fence

while pushing it through the blade

I do this with push stick in my right hand

and keeps your hands well away from the blade. If we are all aware of keeping both your hands one hand width away

I'd rather be the length of a push stick away

from the blade (when possible) then the unexpected slip is where keeping a finger or two over the top of the rip fence (if not using a push shoe) is a good idea. If your fingers / hand slips off the timber your hand will travel along the rip fence and not into the blade.

hmm, sounds like a prime case for the Sawstop!

 

[Sideways]

When you are cutting something thin, you have the choice of setting your blade so that it just breaks through the top of the material, raising the blade full height or anything in between.
My personal habit is to set the blade not more than 5-10mm higher than what I'm cutting. It's the safety thing that I could be cut, absolutely, but it might reduce the risk just a little if something unexpected happened despite all the proper precautions.
With the blade set low like that, I think there is more push back toward the operator so more risk of kick back than if the blade is set high so that the direction of the teeth at the front and back edges is much nearer vertical - up or down.

I once hired some contractors to modify a thick concrete slab. It involved diamond sawing and removing part of it. Completely unknown to me, anyone else, or the site drawings there turned out to be a cable conduit crossing diagonally under the slab. It's only because the saw operator also made his cut using theminimum projection below the slab that we avoided a very expensive mistake. This experience reinforced my bias to keep the blade set as low as works reliably. I do the same when I use the tracksaw.

That's my own bias and why. I can imagine situations where you might want to do it the other way.

 

[Inspector]

Re: The use of push pads.

There was a Youboob video where the US demonstrator was using a pad (might have been a Gripper) to push a piece of plywood through the blade. Pad was between the fence and blade and the blade was about a foot from the fence. The cut piece under the pad was almost clear of the blade when it was grabbed by the blade and spun back and to the left. The presenter never realized how close he came to loosing a bunch of fingers until he looked at the video frame by frame. As the plywood spun and kicked back to the left, the push pad followed, rolling 90º, placing the knuckles over the blade, barely clearing it. He was very lucky not to have ended up in the hospital. He was not using a saw with a riving knife, splitter or guard which would have likely prevented the kick back but thought the push pad would/could control the wood being cut. The pad design puts a hand too close to the blade as do some of the push sticks shaped like a hand plane or wedge. You can shoot me for saying this but Jacob's longer push sticks are better than a pad. I use push sticks, riving knife, guards, etc as appropriate but still appreciate having the extra level of protection a blade brake provides.

Pete

 

[Bingy man]

When you are cutting something thin, you have the choice of setting your blade so that it just breaks through the top of the material, raising the blade full height or anything in between.
My personal habit is to set the blade not more than 5-10mm higher than what I'm cutting. It's the safety thing that I could be cut, absolutely, but it might reduce the risk just a little if something unexpected happened despite all the proper precautions.
With the blade set low like that, I think there is more push back toward the operator so more risk of kick back than if the blade is set high so that the direction of the teeth at the front and back edges is much nearer vertical - up or down.

I once hired some contractors to modify a thick concrete slab. It involved diamond sawing and removing part of it. Completely unknown to me, anyone else, or the site drawings there turned out to be a cable conduit crossing diagonally under the slab. It's only because the saw operator also made his cut using theminimum projection below the slab that we avoided a very expensive mistake. This experience reinforced my bias to keep the blade set as low as works reliably. I do the same when I use the tracksaw.

That's my own bias and why. I can imagine situations where you might want to do it the other way.

Re : the concrete slab . Whenever I have to cut into a floor I try to remove a short piece of floorboard or two and get the lead lamp under the floor to spot any pipework or cables . If I have to cut blind I’ll then set blade a fraction less than the thickness eg 22mm board I set blade depth to 21.5 mm . Using a bolster chisel or similar I force it into the kerf and lever it out , much better to cause a few splinters than cut through a pipe or cable. I use the same method with t/ groove osb / and chipboard..

 

[Jacob]

Re: The use of push pads.

There was a Youboob video where the US demonstrator was using a pad (might have been a Gripper) to push a piece of plywood through the blade. Pad was between the fence and blade and the blade was about a foot from the fence. The cut piece under the pad was almost clear of the blade when it was grabbed by the blade and spun back and to the left. The presenter never realized how close he came to loosing a bunch of fingers until he looked at the video frame by frame. As the plywood spun and kicked back to the left, the push pad followed, rolling 90º, placing the knuckles over the blade, barely clearing it. He was very lucky not to have ended up in the hospital. He was not using a saw with a riving knife, splitter or guard which would have likely prevented the kick back but thought the push pad would/could control the wood being cut. The pad design puts a hand too close to the blade as do some of the push sticks shaped like a hand plane or wedge. You can shoot me for saying this but Jacob's longer push sticks are better than a pad. I use push sticks, riving knife, guards, etc as appropriate but still appreciate having the extra level of protection a blade brake provides.

Pete

He revisited it here. The daft sod is still using grippers on his router table with his hands inches from the cutter.

 

[Inspector]

Believe it or not Jacob but that wasn't the video. Same principles with a different twit! Hopefully they don't get together and mate. Hate to see a family of them.

Pete

 

[Ed Weber]

I don't/won't watch videos like these, other than situation like this. (someone making a point)
These do nothing to entertain me or to educate me in any way.
The moron trying to film kick-back, doing it in a way he has a high probability of injuring himself, seriously. How is this helpful to anyone, except the judges at the Darwin awards?

 

[Inspector]

To get a Darwin Award you need to take yourself out of the gene pool before you reproduce. So the silly gitts that get their junk ripped off or they die while young are great candidates. Oldies like most of us have already passed on their intelligence or lack of it don't count no matter how dumb. Besides being one handed doesn't slow down the wigglers other than maybe putting off potential mates.

Pete

 

[Mike Fletcher]

Push shoes (depending on the design) have two major disadvantages; you have reach over the workpiece to use it which shortens your reach overall, at the end of a pass your hand/arm passes directly over the exposed cutters. Push stick extends your reach and doesn't get as far as passing over the cutter.
I'm slightly mystified by kick-back, never seeming to have experienced it. Kick up on the other hand is prevented by a crown guard, or feather board on the fence, or by a push stick if you are holding it down

I do this with push stick in left hand, and/or pressing in towards the fence

I do this with push stick in my right hand

I'd rather be the length of a push stick away

hmm, sounds like a prime case for the Sawstop!

This will be my last post on this subject as it is getting a bit carried away.
My push shoe is made from an old handsaw handle with a long-ish piece of plywood attached and a hook on the end. My hand only reaches the blade area when the cut is almost complete, and my hand is more than one hand width up and to the right of the blade. My hand never goes over the blade. I always use a crown guard and riving knife. Kick-up occurs first then kickback follows in a manosecond (or shorter).

To me, keeping solid downward pressure on the work piece is essential. Whenever possible I use a featherboard or a push stick to apply lateral pressure against the rip fence, but never opposite the blade.

I addition, I modified my crown guard by adding an adjustable perspex "fence" on the guard on the side of the blade opposite the rip fence. I also have an adjustable angled piece that covers the area in front of the blade. This also comes in handy when jointing a board, when I can lower the perspex fence close to the table keeping all sawdust under the crown guard where it gets sucked into the extractor.

And finally, I see the Microjig Gripper adverts with someone with his hand directly over the blade, with no crown guard an no riving knife. Brave man.

 

[Jake]

My hand only reaches the blade area when the cut is almost complete, and my hand is more than one hand width up and to the right of the blade.

Far too close to the blade for my comfort, whenever in the cut.

To me, keeping solid downward pressure on the work piece is essential. Whenever possible I use a featherboard or a push stick to apply lateral pressure against the rip fence, but never opposite the blade.

Some downward pressure is needed but realistically you are unlikely to be able to it hold down if the blade really catches - hand pressure isn't going to be enough or at least not reliably so. Sitting on the wood might work to stall the blade but would otherwise be counterproductive.

In any case, the notch in the pointy end of the pushsticks lets you exert pressure in two or more dimensions (on the corner of a board, three, down, sideways and forwards). With a pair of pushsticks, that gives as good control as you can expect to have of vertical movement while keeping your hands 300mm or so away from the blade.

I stand to the left of the cut. Left hand push-stick is used throughout, pushing downwards and sideways into the fence as soon as the timber gets about half-way between the table edge and blade - that then stays still as the timber slides under it. Right hand pushes the timber through until the end reaches the table, switch then to using a second push-stick in that hand too pushing forwards and downwards on the end of the wood. When the end of the timber gets to the left hand push-stick, change its angle and catch the corner of what will the offcut, with the pressure increasingly forwards rather sideways until it is just forwards at the very end.