Is the new kickbackstop actually safer than a riving knife?

[gniuts]

Hello,

I recently started woodworking as a hobby and I am considering buying a track saw from Festool. I plan on using it on plywood and solid wood. Since I am a big fan of safety features, I was very interested in the new TSC55K when I saw it was equipped with a sensor that stops the blade in case of kickback. It appears that the sensor (that is triggered when the saw lifts up during a cut) is located where the riving knife normally is.
Since there are no more riving knife preventing pinching of the blade when cutting solid wood, the operator safety relies only on that electronic technology to stop the kickback when it occurs rather than preventing it from happening in the first place. This is why I am wondering whether a real riving knife would not actually be safer and maybe I should consider the TS 55 instead. For inside plunge cuts, however, I think it is a very nice feature.

What are your thoughts on this? Am I missing something?

 

[ChuckM]

Without a riving knife, you run the risk of binding when ripping a long hardwood board. In the picture, the riving knife on the table saw allowed me to finish the cut on the 6' long oak board (1-1/2" thick?) with no binding.

Before I sold my TS75, I had not had one single incident of kickback while using it. So between a track saw with a riving knife and without, I'd still choose the former if I had to rebuy a tracksaw.

Doesn't Mafell have a tracksaw with both the electronic kickback safety and riving knife?

 

[Rob Z]

Same as with Chuck, my older model  track saws (two 55s and one 75) never had a kickback. If I were buying a  new track saw now, I would opt for one with a riving knife vs the electronic sensor dealio.  The reason I say this is if something ever goes wrong with the sensor, I have no hope of fixing that on my own and know it will have to go back in for a repair. If something glitches with a riving knife, I figure I have a chance of figuring it out on my own because it's a mechanical device.

With that said, I am sure that the electronic sensor-equipped track saw has been thoroughly tested and works well and will be reliable for a long time for most users.

 

[Crazyraceguy]

It might just be old-school thinking, but I would rather prevent the kickback potential with the riving knife than to have the tool just stop the motor. Presumably you still need the cut to be made, right? The riving knife holds the kerf open and allows that to happen. The braking device is purely about making the saw blade stop to prevent any further incident. Then what? You still need to finish. So what do you do? wedge some kind of shim in the kerf and start again? Wouldn't the original system have just done that in the first place?
This may just be case of doing this because they can, rather than because it is necessary?

 

[tallgrass]

Why not add the feature to the saw? It does not have to be one or the other. Give me both. Riving knife, and digital wizardry.

 

[slavi.yordanov]

As far as safety is concerned, I think the sensor is better in scenarios where you are just starting a cut, and a mechanical riving knife would not protect you from a kickback. But as others have pointed out, when ripping hardwood, mechanical riving knife is better.

The thin blade of the new TSC55 is the biggest benefit in my opinion. I'm pretty sure those new blades would work with the older models, but the riving knife will not work in that case.

 

[usernumber1]

maybe if you grind down the riving knife?
or TSO makes a replacement 1.8mm? 

 

[Stone Message]

I did not realise that the riving knife had been removed from the anti kickback models.

The riving knife is essential in my view as any cut made where the anti kickback feature clicks in will be uneven. The kickback happens when the stresses in the wood cause the kerf line to close behind the saw trapping the blade. When the saw is removed and restarted the final kerf line will have the whole history of the event.

The only time I ever experienced kickback was in the first few days of using my brand new TS55 - over 11 years ago and the first time I had ever used a plunge saw.

Peter

 

[AlexThePalex]

I like my saw with a riving knife. The physical riving knife in place is much better than any electronic measure can simulate.

Those new thin blades of 2.2 and 1.8 mm have an advantage while cutting, but, they create a problem for the riving knife, because a thin piece of metal of 2.2 or 1.8 mm is not that strong and will bend easily.

It was not a problem with the old blades that were 3 mm thick, solid is heck, but hit a 1.8 mm thin piece of metal from the side and it's bend out of place. And that's hard to fix without replacing it entirely.

 

[gniuts]

Looks like everyone agree on this one  [big grin]

It is a shame indeed they did not add the kickback stop on top of the riving knife. Probably they could not fit everything in the saw.

 

[usernumber1]

I like my saw with a riving knife. The physical riving knife in place is much better than any electronic measure can simulate.

Those new thin blades of 2.2 and 1.8 mm have an advantage while cutting, but, they create a problem for the riving knife, because a thin piece of metal of 2.2 or 1.8 mm is not that strong and will bend easily.

It was not a problem with the old blades that were 3 mm thick, solid is heck, but hit a 1.8 mm thin piece of metal from the side and it's bend out of place. And that's hard to fix without replacing it entirely.

cut the riving knife out of an old 1.8 blade should be pretty strong

 

[AlexThePalex]

cut the riving knife out of an old 1.8 blade should be pretty strong

No.

 

[Crazyraceguy]

As far as safety is concerned, I think the sensor is better in scenarios where you are just starting a cut, and a mechanical riving knife would not protect you from a kickback.

I just don't see that? Every "rookie" I have seen who starts the plunge too close to the end of the material gets to feel the saw jerk down onto the depth stop. It is startling, but not a kickback and not particularly dangerous, probably not so good for the saw though.
With the saw on the track, the only time you could potentially get a kickback is from the blade being pinched by a ripping cut in solid wood. This is not going to happen before the riving knife could get in place.

 

[pixelated]

It’s a different design, but the riving knife of the HK saw seems sturdy enough.

 

[Cheese]

It is a shame indeed they did not add the kickback stop on top of the riving knife. Probably they could not fit everything in the saw.

I think you're right.  [smile]  The way the REB/REQ & KEB are presently configured, the riving knife and the kick-back foot occupy the same area. Maybe if the original marching orders were "redesign the saw to incorporate both" some clever repackaging of the 2 safety systems would have happened.

I've had the REB kick back when I've absent mindedly plunged too close to the starting end. That was on me... [embarassed]

Having said that, I traded in the REB for the KEB and am very happy with it.

 

[Coen]

Kick or no kickback... if the wood pinches the blade, it will still ruin the cut.

So riving knife it is for me.

I've never had a kickback either, but I've had cases where I very much appreciated the riving knife.

 

[Lincoln]

Anti kickback on the Mafell is fantastic, not surprised that Festool have added it to their saws. Makes actual plunge cuts so much easier and safer.

 

[Crazyraceguy]

Anti kickback on the Mafell is fantastic, not surprised that Festool have added it to their saws. Makes actual plunge cuts so much easier and safer.

I always use the stop attached to the track when doing plunge cuts. Not only is it far safer, but you can use it to guarantee the stopping point of the cut.
I do this on inside corners of solid surface counter tops quite often.

 

[Lincoln]

Anti kickback on the Mafell is fantastic, not surprised that Festool have added it to their saws. Makes actual plunge cuts so much easier and safer.

I always use the stop attached to the track when doing plunge cuts. Not only is it far safer, but you can use it to guarantee the stopping point of the cut.
I do this on inside corners of solid surface counter tops quite often.

Yep, I use the same thing on the mafell tracks.

 

[Cheese]

Anti kickback on the Mafell is fantastic, not surprised that Festool have added it to their saws. Makes actual plunge cuts so much easier and safer.

The truth be told...it was because of my experience with the Mafell anti kickback feature over the last 2 years that persuaded me to turn in the REB for the KEB. My initial reaction to the riving knife-less system was one of disbelief, however the Mafell system has been faultless and consequently I assumed the Festool version would be as faultless as well. I've not been disappointed.