Who needs a Riving Knife?

[Jalvis]

Does a rail saw really need a riving knife?

After looking at all the information about the Mafell MT55 compared to the Festool TS55 the main difference is the Mafell doesn’t have a riving knife.

Does anyone have experience about the value of a riving knife or not having a riving knife (MT55)?

I understand what it does but I'm looking for actual experience.

Videos of Mafell MT 55:
Mafell MT55 Demonstration.

Other Mafell Products:
http://www.mafell.de/webtv_en/

Mafell North America:
http://www.mafell.com/open.html

 

[semenza]

Hi Jalvis,

Welcome to the FOG!  [smile]

I have not used the Mafell, but I rip a lot of hardwoods with  the TS55. I can definetly say that on a good number of cuts it has kept the blade from being pinched. Sometimes when I am cutting I will see the kerf closing  behind the saw and I am glad the riving knife is doing its job.

Seth

 

[Jalvis]

By the looks of things its not all that clear if a riving knife is needed.  I was hoping for a Mafell and Festool user to give some input?

 

[semenza]

Jalvis,

It depends what you mean by needed. Needed for safety  or cut quality or both. In my case of ripping hardwood I would not want a saw without the knife, after having it.  It certainly helps prevent burning and keeps the saw from working as hard on many of my cuts. If the wood closes up tight on the blade the saw will kick up,  at the very least really  messing up the cut.
 

Seth

 

[Roseland]

I think the riving knife is much less important on a track saw than a table saw and that is why Mafell omitted it. With a track saw, if the blade becomes bound, it will want to pull the saw into the wood as opposed to a table saw which will want to kick the wood forward.

With a track saw therefore, if the blade does get bound, it is more of an inconvenience than a danger.

Surely on a track saw if you don't have a riving knife, and the back of the blade gets pinched, it will tip the back of the saw up fast.  I see it as a safety feature; it may not always been needed, but when it is you'll be glad of it!

Andrew

 

[jmbfestool]

I think the riving knife is much less important on a track saw than a table saw and that is why Mafell omitted it. With a track saw, if the blade becomes bound, it will want to pull the saw into the wood as opposed to a table saw which will want to kick the wood forward.

With a track saw therefore, if the blade does get bound, it is more of an inconvenience than a danger.

I might be wrong!   I have always thought if a track saw binds at the rear of the blade it wont pull into the wood like you suggest  it will actually throw the saw up.

The blade is spinning downwards at the rear so if something pinches it, it will kick the saw up  not pull it down a riving knife will prevent this rear pinch/binding.

JMB

 

[Deansocial]

the saw tends to go backwards. the ts saws are not powerful enough to really throw the saw back or up. im glad my ts75 has 1 but im glad my hitachi saw doesnt

 

[windmill man]

Brett,

Please put the riving knives back in your other saws. Please Trust me , one day they will save you loosing fingers or having a piece thrown back at you and having your face split open. I have unfortunately seen both things happen , not pretty and dealing with the injuries are not fun let allown living with the aftermath. So please put them back . Please.

Best John

 

[woodguy7]

+1 on what Windmill John says.  I too have seen the aftermath of no Riving knives.  I have also seen someone using a Makita rip snort with no knife.  It blinded & jump back & up & he was very lucky the saw did not go across his thigh.

Why take them off, I just don't get it ,,,,,,

 

[Jalvis]

Why would this thread be deleted?

This is a relevant discussion considering its a comparison between Festool TS saws(with a riving knife) and the Mafell MT Saw(without riving knife).

Everyone needs to remember that most hand operated saws don't have a riving knife and are actually a new concept.  The main point of this thread is to talk about its relevance in relation to the Saws in the original post.  Everyone wants to be safer but due to Mafell's current track saw it begs to question the importance of the device.

 

[Jalvis]

REMINDER: This is not a discussion about riving knifes in table saws.

 

[Corwin]

the saw tends to go backwards. the ts saws are not powerful enough to really throw the saw back or up. im glad my ts75 has 1 but im glad my hitachi saw doesnt

Well, then I guess my TS55 is a powerhouse compared to your wimpy little TS75.  [tongue]

And yes, when you do get kickback from a track saw, it will lift up at the rear and get thrown back -- at least that's what my TS55 has done.  

 

[peter halle]

Whereas my TS-55 came with a riving knife I will assume that the engineers felt there was a reason.  It doesn't interfere with anything in operation - I think I'll keep mine.

If some of the previous posts were implying that a plunge saw can't have a violent kick back - that is wrong.  I think that each of my rails has a scar to prove it.

Peter

 

[AlexThePalex]

I don't get why people would be against a riving knife. Every saw I ever used had one and it never bothered me one bit. I am glad they are there. I am also surprised the Mafell doesn't have one, I thought they were mandatory here in Europe. It is the first one I've ever seen here without a riving knife.

 

[spikfot]

That was weird?

Test.

 

[semenza]

Delete the thread ? No reason to do that. The question about comparing the Festool and Mafell saws is perfectly legitmate and valid. It is interesting that the Mafell doesn't have  a knife.

The idea of removing riving knives that were designed into saws of any type is unacceptable.

And no one should be removing   or otherwise altering the riving knife on their Festool plunge saw for any test purposes. It is designed into the saw, and since it auto retracts does not interfere  with any cutting.

Does anyone have the Mafell and want to post their observations of  how it cuts?

Seth

 

[Nigel]

When I was looking for a plunge saw I was tempted by the newly released Makita - until I realised it didn't have a riving knife.I immediately bought the Festool instead.

I wouldn't dream of using any saw without one,doesn't make sense.

 

[Deansocial]

i think it depends what you do with a saw wether it needs a riving knife or not. My hitachi gets use solely for roofing and i only crosscut with it so does not need a riving knife.

 

[JeromeM]

This is a relevant discussion considering its a comparison between Festool TS saws(with a riving knife) and the Mafell MT Saw(without riving knife).

Everyone needs to remember that most hand operated saws don't have a riving knife and are actually a new concept.

Sorry there you are dead wrong. While they may indeed be a new concept to you and in the US they are not new in Europe. My Elu circular saw that I bought almost 40 years ago had one as did the used table saw. I can't tell you that all circular saws had them I just got the best I could find and it did.

I'm happy to find that you are finally catching up [tongue]

Also FWIW the Mafell KSP55F Plunge Saw has a riving knife

 

[Nigel]

i think it depends what you do with a saw wether it needs a riving knife or not. My hitachi gets use solely for roofing and i only crosscut with it so does not need a riving knife.

I suppose if you restrict it to crosscuts you'll be OK but how many folks are gonna do that with a plunge saw?