Do anti-kickback pawls really work???

[Greg Muller]

Fortunately for me, I have never had a serious kickback (no bad juju, no bad juju), but I am shopping for an easy to remove splitter. Are the pawls effective? Any evidence?

[Ben Rafael]

They have been very effective for me.

[Greg Muller]

So, Ben, you have actually had a dangerous kickback stopped by the pawls?

How much damage to the wood did they do? (I know that wood damage is better than damage to me, I'm just trying to get an idea of how deep the pawls imbedded themselves in the wood for a force reference)..

thanks.

[Steve Sawyer]

From what I understand, anti-kickback pawls are better than nothing, but not really the thing on which you want to rely to deal with kickback.

First you want to prevent kickback if possible. The best defense against kickback is a true riving knife, basically a splitter just shy of the width of the blade that curves up and around the back of the blade. This keeps the stock from contacting the teeth on the back of the blade which is what causes kickback.

The next best thing is a splitter, also close to blade-width, and as close to the back of the blade as possible. The thinner the splitter, the less effective it is. The farther back from the rear of the blade, the less effective it is.

Anti-kickback pawls should be the backup to the preceding two options - if you can't, or don't (despite your best efforts) prevent the kickback, the pawls will at least retard the return of the stock in your direction. However, by their very design the pawls may or may not be effective at this - it depends on how the stock is moving (upwards, twisting, parallel to the table, etc.) and dumb luck as to whether the pawls actually engage the wood.

Other solutions are things like board-buddies and featherboards, both of which will retard the movement of the stock in a kickback situation, but again the way the wood reacts to the kickback, as well as the condition of the wood surface and the device (i.e. how much swarf and sawdust is there lubricating that interface) will determine their effectiveness.

[Jim Broestler]

They seem to be good at keeping the cutoffs down, preventing them from being caught by the blade and flying toward me. As far as keeping a workpiece down in the event of a kickback, I have yet to find out because I use a couple different safety measures to prevent it (after nearly losing a finger because I didn't keep the guard/splitter on).

[Glen Blanchard]

Prior to my SawStop purchase, I owned (and loved) a JET cabinet saw - and before that a JET contractor saw. Both of my JET table saws had anti-kickback pawls, so I was accustomed to them being there. I can't say that they ever prevented a serious kickback, as I have never had one of those. When I purchased my SS, I was at first a bit disconcerted with the lack of anti-kickback pawls. I even began a thread here asking about their importance. Bottom line is that if you have a splitter or riving knife, there is not a great need for these things. I do not miss them with my SawStop.

[Ben Rafael]

Mine have left small pin size holes in the lumber.
IMO, you should have both the pawls and a splitter. With narrow stock the pawls can be a bit of a pain, it those cases I just secure them out of the way.
The pawls actually cause more damage to my miter sled than to any wood I've run through my saw.

[Ben Rafael]

I agree with Steve, if you can have a riving knife then that is far better than pawls. Unfortunately riving knives are not commonly available on saws in the US.

[Rick Gifford]

But, all the big manufactuers are putting the riving knives on their new models. Your going to see them alot from now on.

[Greg Cole]

Hey Greg,
The factory guard with pawls on it never made it on the saw.
I used (still do) the MJ snap in splitter. It's OK. I'll give it to you if you want it when I get the new guard installed (have the mounting-spacing template & 2 splitters). Good for 3/4" material or thinner as they splitter part's not too tall, 'tis better than nothing.
I finally got my Shark Guard delivered and am working toward getting that installed, hopefully this weekend.
I too would rather gear up to have things in place to avoid kick back versus rely on some stamped steel pieces as a kick back deterrent. The splitter with the shark guard work much like a riving knife except it's stationary (to there are a couple height splitters for different thickness materials).
Cheers.
Greg

[Lee Koepke]

they also leave small holes in your fingers if they are in the wrong place during re-installation of your guard assembly .... :rolleyes:

[Roland Chung]

Hi Greg,

Try to find a good splitter with the anti kickback pawls. It's not so much that we would remember being saved from a nasty kickback by the pawls - they work more like a finger board, almost passively. Once the board gets past the rear part of the blade and is "held down" by the pawls, the board can't ride up on the rear teeth (coming up from below the table) and get kicked back at you.

A good splitter helps keep some wood boards from closing up around the teeth in the rear of the blade, preventing the board from lifting and getting thrown back at you.

It is the lifting action of the teeth at the rear of the blade that is trying to get you. The two functions of the splitter with the anti-kickback pawls helps resist this.

There are some limitations:

1) My pawls don't grab melamine.
2) There is a danger zone after the board passes the center of the blade and before it reaches the splitter and pawls, where the board could lift off and be thrown at you.
3) The pawls work better if you sharpen them occasionally.
4) The pawls can leave marks, but it has never been a problem for me. I've never seen them on finished work.
5) I've seen solid wood boards try to close up more than plywood or melamine or mdf.
6) Never had a kickback using a splitter and pawls.
7) I've had nasty kickbacks using a jobsite saw without the blade guard/integrated splitter and pawls.

Someday, I will even move up from the splitter and pawls to a table saw with a riving knife. Good luck and get a good one!

[Dan Lee]

When I purchased my SS, I was at first a bit disconcerted with the lack of anti-kickback pawls.

Glen
Didin't you get the second knife that has the plastic blade guard and pawls?
Dan

[Glen Blanchard]

Glen
Didin't you get the second knife that has the plastic blade guard and pawls?
Dan

Ya know Dan, that thing is hanging on my wall and I have never really even looked at it. It went straight from its packaging to being a wall adornment. I have an Excalibur overhead guard, so I went right to the stand-alone splitter.

[Jim Becker]

When I bought the Biesemeyer snap-in splitter for the Jet cabinet saw I used to own, the very first thing I did before installing it was remove the pawls. I don't like them and can't really see their benefit when the splitter is in place to keep material from riding up on the blade in most circumstances. They also can damage thin veneers if they get the least out of adjustment. Additionally they totally get in the way of narrow rips and using a push block. You'll not see pawls on a Euro riving knife, either...

[Nissim Avrahami]

I was reading a thread on the "other" forum that a guy got a kickback that completely broke the anti-kickback pawls away from the saw, throwing them toward him together with the workpiece......

niki

[John Thompson]

About 20 years ago or so, I almost severed a finger with a kick-back pawl. The saw was off and the guard raised to change a blade. The shield and guillotine pawls dropped and did their thing.

I took them off and won't use a saw with them. But.. I do add a crown guard on top to stop upward movement in a kick-back. So... all things considered.

Sarge..

[Bill White]

Guess that I'm just a sissy, but I use the splitter with pawls, Board Buddies, and a GripTite when sawin' whenever possible. So far, so good. I got hit pretty badly several years ago, and I still remember.
Bill

[Steven Wilson]

I couldn't stand the pawls on the Beis splitter I had installed on my PM66. Besides marks, the pawls can actually exacerbate problems especially with thin and narrow stock. A properly adjusted riving knife (following the curve of the blade 2-3mm in back of the blade) does what the pawls were designed to do (keep wood from hitting the back saw teeth) and does it much better without messing with your stock. FYI, if you remove the guard and pawls assembly from the stock PM66 guard/splitter and add an overarm guard you actually have a fairly nice, useable setup that isn't too painful to change. Not as good as the European riving knife assembly, but not too bad.

[Tim Marks]

When I purchased my SS, I was at first a bit disconcerted with the lack of anti-kickback pawls.
The sawstop manual shows that the bladeguard (not the low profile riving knife) has anti-kickback pawls on them.

I think they are required by the CPSC.

Do you just not use your bladeguard, or are you using an earlier version of the saw? Or is their manual wrong?

http://www.sawmillcreek.org/attachment.php?attachmentid=80975&stc=1&d=1202343414

[Glen Blanchard]

Do you just not use your bladeguard, or are you using an earlier version of the saw? Or is their manual wrong?

Okay, I'll repeat the response you will see four or five posts above this one......

------------------------
Ya know Dan, that thing is hanging on my wall and I have never really even looked at it. It went straight from its packaging to being a wall adornment. I have an Excalibur overhead guard, so I went right to the stand-alone splitter. ------------------------

[Peter Quinn]

Hey greg, I got the biesmeyer splitter with pawls insert on my pm66 and it works great. Easy to install, goes on and off quick for setups where its in the way, cheaper than an ambulance ride. I have seen it hold down squirrely African mahogony that I'm sure would have come back on me otherwise. Not good for prefinished plywood, but doesnt seem to scratch things otherwise, plus never really had a problem with the plywood pinching anyway.

Had a run in with some crotch walnut a few days before I bought it that scared me good. Lots of other saftey protocols (ie: powerfeed, featherboards, body position, homemade splitter, knee kick shutoff switch, bandsaw big stuff, etc.) to keep in mind, but those pawls are my last line of defense in the war to keep my teeth in my gums.

[Bob Feeser]

http://inlinethumb64.webshots.com/3711/2866291660100733997S600x600Q85.jpg

I know that there are differing levels of experience on this site. I experienced a kickback on my older Sears 1 hp contractors saw. The piece of wood was about 2 inches wide, and flat on the end, thank goodness. If it was sharp on the end, I would have been impaled. As it was, it caused a blunt imbrasion that brought some blood to the surface, and the pain was there for a couple of weeks.
So for those who would benefit from an understanding of the mechanics of the event, I drew up a little graphic, that you can see in the thumbnail.
As you can see the green block is your workpiece. As the workpiece is exiting the back of the blade, the rearmost part of the spinning blade is spinning upward, so something needs to keep it flat on the table. If the piece gets loose, it can catch on the blade, and be lifted off of the table.
Once the blade starts to lift the workpiece off of the table, it grabs and tilts the workpiece, and the resulting angle binds, and the spinning blade at full speed, with jagged teeth on it, grabs the workpiece, and turns it into a bullet.
I no longer stand behind the workpiece when I cut it. I use a long push stick, with a long nose on it, to keep the back end of the workpiece down. Now back to the safety devices that do this for you.
The reason I bring this up is not to insult those who obviously already know this, but to those, who like myself, never had a kickback problem, and therefore was not really cognizant of the nature of the problem. Never studied, never gave it a thought, then my stomach brought it to my attention.