What's The Big Deal About A Riving Knife?

[Bill Space]

OK...

I think the big deal is the fact that, on my saw that has a riving knife, the blade guard splitter moves with the saw blade and keeps equally close to the blade at all elevations of the blade.

The riving knife is normally only used for non through cuts, and would not be used in through cut applications.

If one wanted to operate the saw with the blade guard off, the splitter offers (on my saw anyway) anti kickback fingers that the riving knife does not have.

So...it seems to me the fact that the blade guard splitter remains close to the blade is of more value than a riving knife that is only used with non-through cuts.

I bring this up because the Grizzly catalog adds tout "...With Riving Knife" and this led me to believe that I wanted/needed the safety feature the riving knife offered.

But what I really wanted, and did not realize it, was the splitter that does the same thing as the riving knife!

Am I on target, or missing something?

[David Helm]

I'm confused about your assertion that the riving knife is not used on through cuts. On my saw, it is used on all cuts.

[Ken Fitzgerald]

I use a Ridgid TS-3650. My saw has a splitter and not a riving knife.

It's my understanding that a riving knife raises and lowers with the saw blade and keeps the distance between the blade and the riving knife the same regardless of blade height. Thus, it would be safer than a splitter when ripping thinner woods that might have a lot of movement.

A splitter's physical position is set so the distance between the splitter and the rear edge of the blade varies with blade height adjustments.

Is it important? It could be. Depends on the tension be released on the particular piece of wood you are ripping. I have seen some wood that closed up almost as fast as the blade opened it. It was closing very close to the rear edge of the blade as it protruded up through the table top. I was astounded the first time I witnessed this.

I am one of those who never removes my blade guard unless I am doing non-through cuts. My blade guard has spring-loaded anti-kickback pawls and a splitter.

So is a riving knife safer than a splitter? Maybe. It could be.......depending on the wood being ripped.

JMHO.

[glenn bradley]

I believe there is a misunderstanding. The riving knife can be used for non-thru cuts and the blade guard is used for everything else (theoretically). For those not wanting the interference of the blade guard, the riving knife can be used for all cuts. Different makers offer different version of this; tall and short RK's, short RK and guard, fingers, fingers that lock out of the way to prevent surface damage, etc, etc. The big deal for the RK is as Bill begins his post; it stays the same distance from the blade regardless of height or angle which of course, the splitter does not. I do understand the preference for pawls but, your guard should have those built in (of course, some don't). I think in a nutshell the "big deal" is that the RK disallows most forms of kickback by disallowing material from getting behind the blade and therefor, launched ;-)

[Bill Space]

Hi again,

My saw is the Grizzly G1023RLWX... The splitter which is used with the blade guard is inserted in the same slot as the riving knife. The splitter also has the same profile as the riving knife, from what I can see. I will verify this and if this is not the case, will report back, for sure.

The splitter will move up and down just like the riving knife does, keeping the same distance from the blade. (about 1/4 inch or so, maybe less)

I did not realize that other saws with riving knives had splitters that somehow attached to the saw differently than the riving knife does. If this is the case, the Grizzly design appears superior.

I was surprised that Grizzly stresses " with riving knife" when in fact "with riving knife capable splitter AND riving knife" would be a claim that carried an even stronger safety message.

This is the point I was trying to make, I think...

So I expect I will remove the riving knife and insert the splitter in its place. By doing so I will have the anti kickback fingers in place as well. And I will have the blade guard too, if I elect to use it, which I plan to as it seems to be a nice one and still allows good visibility of the workpiece and the blade...The blade guard is easily attached and removed from the splitter/finger piece.

Naturally, the riving knife will go back in place for non through cuts...

[Ken Fitzgerald]

Bill.....It sounds like the best of both worlds!

[Mikail Khan]

Hi again,

My saw is the Grizzly G1023RLWX... The splitter which is used with the blade guard is inserted in the same slot as the riving knife. The splitter also has the same profile as the riving knife, from what I can see. I will verify this and if this is not the case, will report back, for sure.

The splitter will move up and down just like the riving knife does, keeping the same distance from the blade. (about 1/4 inch or so, maybe less)

I did not realize that other saws with riving knives had splitters that somehow attached to the saw differently than the riving knife does. If this is the case, the Grizzly design appears superior.

I was surprised that Grizzly stresses " with riving knife" when in fact "with riving knife capable splitter AND riving knife" would be a claim that carried an even stronger safety message.

This is the point I was trying to make, I think...

So I expect I will remove the riving knife and insert the splitter in its place. By doing so I will have the anti kickback fingers in place as well. And I will have the blade guard too, if I elect to use it, which I plan to as it seems to be a nice one and still allows good visibility of the workpiece and the blade...The blade guard is easily attached and removed from the splitter/finger piece.

Naturally, the riving knife will go back in place for non through cuts...

I have a Grizzly 691 with a similar design. I believe what you are refering to as a splitter is actually a riving knife on which the guard mounts. This design is similar to the Bosch TS4000/TS4100 design where the guard cannot be easily removed without removing the riving knife.

20 years ago I read a British Standard for table saws. IIRC it specified a maximum distance for the riving knife from the blade.

MK

[Jim O'Dell]

Yes, the Grizzly saw has both a true riving knife, and a riving knife with a guard that also goes up and down with the blade. To me that is different than a splitter. My Ridgid 3612 has a splitter with a guard attached that also pivots with the blade, but does not go up and down with the blade. Most splitters sit behind the blade on the insert and do not move at all.
I've contemplated taking my knife with the guard, cutting it down to match the riving knife height, and having it ground to work with a thin kerf blade (I have a 30 tooth Forrest WWII that has been used once in my Ridgid 3612.) I imagine getting the dedicated ripping blade I want would be cheaper.:D Jim.

[Bill Space]

Yes, the Grizzly saw has both a true riving knife, and a riving knife with a guard that also goes up and down with the blade. To me that is different than a splitter.

I finally get it! I was thinking the riving knife was the "knife looking" piece, without the guard. But in fact, the riving knife refers to the piece that moves with the blade, and stays close to it, regardless whether the piece that moves with the blade has a guard attached or not.

Soooo... Grizzly supplies two riving knives with their saws, one to use with the blade guard, and one to use without the blade guard when making non-through cuts.

I am surprised I did not realize that to begin with!

Thanks to all for helping me see the obvious!