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SAWSTOP, riving knife, new blade guard - Is history repeating itself?

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Forum topic by ChuckM posted 1114 days ago 3221 views 0 times favorited 22 replies Add to Favorites Watch
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ChuckM

497 posts in 2293 days


1114 days ago

Topic tags/keywords: sawstop tablesaw safety riving knife

Robert Lang of PWM wrote this in his latest blog titled “Where Do Table Saw Safety Rules Come From?”

“The Consumer Product Safety Commission, which is a government agency became interested in table saw injuries in the late 1990s, just before the introduction of the SawStop. CPSC looked to UL to re-examine and possibly improve the standards. In December of 1999 CPSC called for a meeting with representatives of the Power Tool Institute. The summary from PTI is typical of the manufacturers view of guards “The splitter/spreader guard is the most appropriate for common wood cutting and is the industry standard.” “PTI believes the current spreader guard is the best possible guard for most thru (sic) cuts. Education is the only way to affect the injury hazard patterns seen. Education, not redesigning the guard, is needed to convince the operators to use the blade guard.”

He concluded: Experienced woodworkers knew the guards were junk, and those of us who had seen European guarding systems began to ask why did they have such good guards on that side of the ocean. One of these woodworkers, Kelly Mehler became involved in working with UL to improve our guarding systems. If you like the new guards better than the old ones, Mehler is the guy to thank. So where do we go from here? PTI says give the new guards a chance, but CPSC appears to be leaning in the direction of requiring something more. I’ve worked in shops that had signs posted that said “Safety First”, and I wish that everyone involved in this mess would work on that principle. That’s what we should be talking about, not corporate profits, winning and losing lawsuits, or how to write the rules to favor one business over another.

Read the whole blog here: http://www.popularwoodworking.com/woodworking-blogs/editors-blog/where-do-table-saw-safety-rules-come-from?et_mid=513331&rid=3333165

-- The time I enjoy wasting is not time wasted


22 replies so far

View Steven H's profile

Steven H

1113 posts in 1686 days


#1 posted 1114 days ago

No matter how the riving knife is improved or engineered We will still get morons who put their fingers near the blade. Or do stupid things where kickback can occur.

They should be teaching common sense.

View NathanAllen's profile

NathanAllen

376 posts in 1770 days


#2 posted 1113 days ago

Riving knives help you avoid kickback
Kickback is every bit as dangerous as sticking your finger into the blade
Kickback risk can be reduced by following basic safety; but not eliminated due to wood pressure being released
More hobby users have brought home 220v cabinet saws as incomes have increased

While I’m not a SawStop user (next saw will be one) I only remove my low profile riving knife when using my dado blade. Anyone who has seen kickback shouldn’t think twice about removing your plate and dropping in your riving knife.

View mtenterprises's profile

mtenterprises

817 posts in 1319 days


#3 posted 1113 days ago

cr1 – yes, Yes, YES!!!!!! AND YES!!!!!!

MIKE
PS – YES!!!!

-- See pictures on Flickr - http://www.flickr.com/photos/44216106@N07/ And visit my Facebook page - facebook.com/MTEnterprises

View Rob_G's profile

Rob_G

13 posts in 1245 days


#4 posted 1113 days ago

The owner of Sawstop is a patent attorney,and he was lobbying the CSC to make his technology a requirement on all saws. He didn’t get it passed.

View dbhost's profile

dbhost

5378 posts in 1858 days


#5 posted 1113 days ago

While I do agree, something needs to be done to prevent injury. The riving knife is an excellent, common sense example of how to solve the problem of the wood pinching behind the blade and causing kickback.

SawStop is a good technology, but to even begin to view it as a panacea is foolhardy at best. Users that get used to the idea that a blade will stop if my flesh touches it, will tend to make that assumption elsewhere, where the technology has not been adapted to say the miter saw, band saw, or router. And what about those times when the safety feature is turned off for cutting say PT lumber?

If you don’t believe me that people make stupid assumptions about technologies and where they are applied, do you recall hearing about computer users breaking their “cup holders” off? Need I say more?

Problems are not always best solved by technology, or restriction, but rather by processes and education.

-- My workshop blog can be found at http://daves-workshop.blogspot.com

View EvilNuff's profile

EvilNuff

59 posts in 1254 days


#6 posted 1113 days ago

It is one thing to want to avoid a saw stop. There are, after all, political and even usage reasons. However, IMO, it’s nothing short of crazy to avoid using a riving knife. When you cut wood and expose fresh parts to air it can move on you. No amount of preparation or good practice can prevent this. Riving Knives can…why on earth wouldn’t you use it?

View ChuckM's profile

ChuckM

497 posts in 2293 days


#7 posted 1113 days ago

As I see it, removing the riving knife brings no benefits but serious risks to a woodworker. Even with the use of a riving knife, kickbacks can happen, let alone without one. Some smokers lived beyond 80 or even 90 before they died but that doesn’t mean smoking has no effects on a person’s life expectancy. The late Sam Maloof used his bandsaw without the guard and neither does that mean we should remove the blade guard from our bandsaws.

Kickbacks can cause serious injuries. The following kickback happened when the woodworker ripped a piece with the blade tilted towards the fence.

Warning: Do not check out this injury incident recently posted by a woodworker on another woodworking forum if seeing blood or wound may cause discomfort to you. You have been warned.

http://www.sawmillcreek.org/showthread.php?170208-Kickback-Hurts!-%28WARNING!-GORY-PICTURES!!%29&s=da9c3aa6d4e9ff9c3456db41420fc7fe

(No matter what, do not tilt the blade towards the rip fence!)

-- The time I enjoy wasting is not time wasted

View Manitario's profile

Manitario

2300 posts in 1509 days


#8 posted 1113 days ago

my wife’s grandfather worked 50+ years without any safety guards on any of his tools. He is alive and still has all his fingers, and only suffered one serious chainsaw injury (he had removed all the safety guards off the chainsaw too). Therefore, because he was safe, it means we all should be ok removing all safety features that the big bad government mandates, we just need more common sense. This argument reminds me of the people that swear smoking is safe because they had someone in their family that smoked and lived to age 100…if only we all could be so lucky…

-- Sometimes the creative process requires foul language. -- Charles Neil

View Greedo's profile

Greedo

465 posts in 1587 days


#9 posted 1113 days ago

one thing about any safety features is that they increase the perception of risk when they are removed, my first saw had no riving knife. i used it that way and it seemed normal to me, kickbacks were frequent so you just learn not to stand directly behind.
my next saw had a riving knife and it felt so much safer, though as i could still see the blade i was tempted to go very close with my fingers
and my current tablesaw is a modern slider with riving knife and dust collection hood mounted on it, the riving knives in europe must extend above the blade so that you cannot make non- through cuts, a forbidden operation.
i always have all these safety features mounted as they make work safer and for most operations they do not form any hindrance. the blade is almost completely hidden by the hood witch makes accidental contact very unlikely, and you do not see the blade so you don’t put your fingers anywhere near.
but for other operations i need to dismount the riving knife or dust hood, like when cutting tenons.
and because i am not used to seeing a “naked” blade spinning like that, i become super cautious.

so yes the number one cause of accidents are user faults because of distraction or inattention etc… but no matter what type of saw you work on, with witch safety features or not. you will always get used to it, and your fear of danger will diminish evenly over time. up to a point where the only thing that can save you from your own mistakes are the saws safety features.

i would have gotten sawstop technology if it was offered by the manufacturer of my saw, not the sawstop itself because first, nobody uses old style cabinet saws like that in europe anymore. and second i don’t like their fear mongering attitude to make money out of fear, where safety is just a pretext.

View Mark Shymanski's profile

Mark Shymanski

5078 posts in 2339 days


#10 posted 1112 days ago

A while back one of the fellows from work wanted me to help him with a desk project he was working on (keep in mind this fellow carries more pips on his shoulder than I do). He arrived at my shop we unloaded the wood and I handed him safety glasses, ear plugs and explained basic rules of my shop. He looked at me with that ‘Really? look and asked if I was serious….I told him if he wanted the wood cut he’d put the gear on and follow the rules. He did, we cut the wood everyone was happy and in one piece. I think you need both safety features of the tool and respectful understanding of the tool’s operation and safety procedures.

I have adopted one safety practice that had not occurred to me before, one that I picked up at the wood working classes I took last winter. Do not walk away from a tool with the blade still moving. This really was driven home for me this summer when Jenn and I were reflooring our son’s bedroom. I noticed that the moving bandsaw blade looks very much like a static blade, so I now stay beside it until it stops, that way I know that Jenn won’t put her work down on the table and accidently come in contact with a slowing but still dangerous blade.

-- "Checking for square? What madness is this! The cabinet is square because I will it to be so!" Jeremy Greiner LJ Topic#20953 2011 Feb 2

View EvilNuff's profile

EvilNuff

59 posts in 1254 days


#11 posted 1111 days ago

“In all but the worst of conditions the riving knife does nothing that can’t also be accomplished by holding the work down against the table. “

I’m sorry but this is just factually incorrect. If you don’t want to use one then I fully support your choice to do so. I will disagree vehemently with anything said that will lead others into unsafe practices.

View Letorix's profile

Letorix

119 posts in 1129 days


#12 posted 1108 days ago

I woke with numb hands today, guess I shouldn’t have tinkered in the garage after work.

Big Sigh….

View Greg..the Cajun  Box Sculptor's profile

Greg..the Cajun Box Sculptor

4990 posts in 1935 days


#13 posted 1108 days ago

-

-- If retiring is having the time to be able to do what you enjoy then I have always been retired.

View Chris Camp's profile

Chris Camp

14 posts in 1502 days


#14 posted 1107 days ago

I can’t think of a single situation, other than making cove cuts or plunge cuts, in which a riving knife would get in the way. Aside from those two operations, I have never had a reason to remove the riving knife.
While it is true that on it’s own, a riving knife does not totally eliminate kick backs, it does significantly reduce the occurrence of them, and it makes it much easier to control or stop kickback if it begins.
I don’t see any reason NOT to use a riving knife.

-- I'm always thinking one step ahead, like a carpenter building stairs...

View Bertha's profile

Bertha

12951 posts in 1319 days


#15 posted 1107 days ago

comment deleted. I now understand kickback. Thanks to the posters below.

If I were going to spend a bunch of money on safety features, I’d go with the better DESIGN incorporated into European sliders (which are older than Gass, last time I checked).

They have appropriate safety features available for even my vintage saw. They range from common safety sense to an overtable guard/boom. I don’t possess much of either, to be quite honest. They don’t yet make a SharkGuard for my machine but that’s generally a pretty respectable sub-$200 safety feature. I just don’t think the situation is that “broken” that we need a governmental white knight galloping into my shop to rescue me from myself. There’s enough “rescuing” going on already, arguably.

-- My dad and I built a 65 chev pick up.I killed trannys in that thing for some reason-Hog

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