# How important is a riving knife on plunge saws?



## s-cup (Oct 21, 2018)

Hi


I'm in the process of buying a plunge saw and it has basically been boiled down to a choice between the Bosch GKT55 and the Dewalt DWS520, mainly due to the fact that they are slightly cheaper than the competition while still getting very good reviews.


I'm mainly thinking about getting the Bosch because I already have a Bosch router and it's my understanding that I can buy a router guide that fits the router to the guide rail. On top of that it seems to be easier to find stores that sell the Bosch as well as finding reviews.
A small positive thing is that you can use guide rails from other manufacturers on the Bosch, not that I plan to do it but still.







The only drawback I can see with the Bosch is that it's less safe since it lacks a riving knife or anything like it, which the Dewalt has.


But... there are so many manufacturers, including some of the most well known, out there that don't put a riving knife on their plunge saws and I'm guessing (hoping) there's a reason for it, maybe it's not needed. 


What's you opinion, is it needed or not?







_Disclaimer: I'm a total beginner when it comes to power saws so maybe_ I'm asking something obvious but I tried to google without any luck.


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## canarywood1 (Jun 9, 2016)

I think if you called it a track saw as what it's usually called as opposed to a plunge saw, you would get some answers.


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## GeorgeC (Jul 30, 2008)

canarywood1 said:


> I think if you called it a track saw as what it's usually called as opposed to a plunge saw, you would get some answers.



Thanks. I was wondering just what was a plunge saw. 



Is that not just a circular saw on a track? Why would it have a riving knife?



George


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## John Smith_inFL (Jul 4, 2018)

you are talking about the track saw.
a table saw has a riving knife (splitter).
a circular saw does not.


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## _Ogre (Feb 1, 2013)

i'd think a riving knife on a hand held saw would be more of a pain to use the saw


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## Terry Q (Jul 28, 2016)

I have a grizzly tracksaw that has a riving knife. It’s never been an issue one way or the other. I use my track saw for cutting up sheets of plywood where the wood isn’t under tension and the riving knife would be of questionable benefit, but if I were to rip lumber with a track saw then I could see where there might be a benefit to a riving knife.


In woodworking there is always more then one way to accomplish something.


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## s-cup (Oct 21, 2018)

canarywood1 said:


> I think if you called it a track saw as what it's usually called as opposed to a plunge saw, you would get some answers.


Well... I did say I was a total beginner . But in my defense people do call them plunge saws, >30,000,000 hits on google is your proof. But I guess track saw is the correct term.



GeorgeC said:


> Is that not just a circular saw on a track? Why would it have a riving knife?
> George


Since I've already made my (lack of) knowledge clear in the matter I guess I could make it worse and ask why shouldn't they have one? I can imagine that a track saw is less likely to cause a kickback or whatever, but do they really eliminate the risk completely?

After all, there are some track saws that has a riving knife.



John Smith_inFL said:


> you are talking about the track saw.
> a table saw has a riving knife (splitter).
> a circular saw does not.


Like I said, the Dewalt has a riving knife as well as another mechanism to prevent the saw shooting backwards. The Festool (which seems to be the god among track saws according to some) also has a riving knife. Some others have as well but it seems like it's a minority.


Picture of the Dewalt:
 http://tic.wpengine.netdna-cdn.com/wp-content/uploads/2010/01/IMG_3016.jpg
Picture of the Festool
 https://i.ytimg.com/vi/LQQ4Bfsv2o8/maxresdefault.jpg




_Ogre said:


> i'd think a riving knife on a hand held saw would be more of a pain to use the saw


From my understanding they are barely noticeable since they are not fixed in place but that they only lowers once there's space to do so.


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## Terry Q (Jul 28, 2016)

As far as plunge cutting, that is one thing you can do safely with a track-saw, not so controllable and comfortable to do with a circular saw.

By the way, I’ve done that with my grizzly track saw, which has a riving knife, without difficulty.

This is in no way a recommendation to buy a grizzly saw over something else, just an observation for those unfamiliar with the term plunge saw and riving knives on track saws.


In woodworking there is always more then one way to accomplish something.


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## sunnybob (Sep 3, 2016)

In the beginning of power tools, there was a circular saw. You had to adjust the depth of cut before you started and that was that.
Then it developed into a plunge saw, where you could push the saw down.
Then someone invented a track for the plunge saw to be used on site as a portable table saw.


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## hawkeye10 (Feb 18, 2015)

I have a Triton track saw and really like it. If I were a pro I would buy a Festool or Bosch, but I don't break down plywood every day all day long. I don't need to spend the extra money for a top of the line saw. As far as kickback I think you might be worrying about it too much. Track Saws have an anti-kickback built into them and that will stop any kickback. On my saw I have it disconnected. A track saw has a lot less chance of kicking back than a regular circular saw because it's setting on a track. It's like a train it is going where the tracks take it. Don't forget Christmas is coming and there will be big sales. :smile2:


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## s-cup (Oct 21, 2018)

Thanks for the replies.

A funny thing to mention is that I also asked almost the same question on a swedish forum and from the ten or so answers everyone said it would be stupid to buy a saw with no riving knife.

Wonder if we swedes are more concerned about safety than others or if it's a coincidence.


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## NoThankyou (Mar 21, 2018)

I've seen a few demonstrations of track saws. They are very impressive for what they can do. The Festool system has incredible dust control. I'm going to use the word almost, please take it at that.

The Festool is so clean that it almost could be set up in a client's living room to do the job. 

Track saws in general are contractor job site tools. Generally they are a lighter and easier to set up tool that replaces a very small table saw. 

Which brings up a question that you need to answer. 'Why would you get a track saw rather than a table saw if you are just starting out?'


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## s-cup (Oct 21, 2018)

NoThankyou said:


> Which brings up a question that you need to answer. 'Why would you get a track saw rather than a table saw if you are just starting out?'


The simple answer is a lack of space. I do have a small outhouse where I in theory could set up a table saw but it’s so narrow that it would be almost impossible to use it in reality.

I have plans to renovate a bigger outhouse so it can be used as a woodshop but that’s not until a couple of years in the future.


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## ORBlackFZ1 (Dec 25, 2013)

s-cup said:


> Thanks for the replies.
> 
> A funny thing to mention is that I also asked almost the same question on a swedish forum and from the ten or so answers everyone said it would be stupid to buy a saw with no riving knife.
> 
> Wonder if we swedes are more concerned about safety than others or if it's a coincidence.


Interesting comment....be very careful with making decisions based on information from internet forums. The term "with a grain of salt" is common in the US? Is there a Swedish translation?

Again as someone else has hinted at, it really depends on what you are going to cut with the "plunge" aka "track" saw. 

I have a Makita Plunge Circular saw (https://www.makitatools.com/products/details/SP6000J). I have used it since 2014 for cutting sheet goods (plywood & MDF). I have a large table saw in my wood shop. As I get older, it gets harder to handle a 4'x8' sheet (especially 3/4" thick MDF) on my table saw. The Makita allows me to make cuts on sheet goods. I have both the short (55") and long (110") tracks. The Makita dust port works very well with my shop vac. I use a sheet of 4'x8' foam insulation (https://www.homedepot.com/p/Owens-C...ared-Edge-Insulation-Sheathing-52DD/202085962) under the sheet goods. The combination of both the dust port with my shop vac and the sheet foam insulation allows me to use the Mikata for many cuts without adding particles to the shop air.

Your question about the riving knife is an interesting one. I can NOT recall any time with the Makita that the riving knife would have made a safer or better cut with any of the sheet goods that I cut. I can think of two instances that a riving knife might help. 1) If I was ripping real wood materials, a riving knife may make the cut safer. 2) If I was using the Makita WITHOUT the track saw, but why would I do that?

Real wood may have stresses that are released when a board is ripped. Not so often when cross-cutting the wood, but it can happen. The stress may make a straight board have a curve to it. This curve is what can cause the board to "pinch" the back (non-cutting) side of the blade. (Sheet goods don't have these stresses by design. If you find they do, then my recommendation is to take the sheet goods back to your retailer and complain loudly!)

The purpose of a riving knife is to keep the material being cut from closing in on the non-cutting (back) edge of the blade. With a table saw, if the material closes in on the back of the blade, the blade would move the material back at the operator at a very high speed. This is important on the table saw, because the operator would be standing right in the path of the material. Many table saw users have experienced this movement which is commonly referred to as "kickback".

A track (plunge) saw has a completely different design from a table saw. It usually does not have "kickback". When the blade gets trapped it will usually stall on smaller models. On large models, you may experience a sharp "jumping" movement of the circular saw, but the material being cut should not move. If the material is moving, then you are cutting too small of a piece of wood OR/AND you don't have it held down properly!

Notice the difference between the two operations. With the table saw, the material being cut is moving and is NOT clamped down. It is usually hand held or push stick held. With the track saw, the material is clamped down and the track saw is firmly held by the operator with nice easily held hand grips on the track saw. There is a BIG difference!

So, I would recommend that you consider other important factors in selecting your track saw to purchase. Other factors that you may consider are:

1. How does the saw feel in my hands? Can I have a strong comfortable grip on the saw while in use?

2. If I am using the plunge saw indoors, how is the dust collection port? Does it work? Does my shop vac work with the plunge saw port?

3. Is the saw too heavy to be used for the length of time I want to use it for?

4. What is the warranty like?

5. Will the saw run on my voltage (110 vs 220 VAC)?

6. Is the power cord long enough for my work area?

7. What is the cost of the track saw?

8. What are the cost of the accessories? Short track, long track

9. Can I get blades for the saw? Are they a standard size? 

10. If I decide to do rip cuts on real wood, is there a ripping blade available?

Etc, etc, etc, .....

The last point is the first one in this post...match the tool to the task at hand. Plunge (track) saws were designed for cutting sheet goods. I am sure that you can use them for cutting other materials, but you have to ask yourself is it a safe operation for you and your environment. Yes, I have seen tradespeople use a hammer to put in a screw. But you have to ask yourself, was it safe and how effective is the screw going to be?

Keep us posted on which Plunge (track) saw you decide to purchase. 

Please post a review of the tool in the Tool Review forum after you have had some experience with the tool. Share your experience with others that have shared with you.

Eric

Full disclosure...My shop is filled with Bosch tools. When I purchased my Makita Plunge saw, Bosch did NOT have an equivalent version. The only manufacturers that I found with Plunge (track) saws were DeWalt, Makita, Festool and Grizzly. If I was purchasing a track saw today, I would include the Bosch in my selection.


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## ORBlackFZ1 (Dec 25, 2013)

*Bosch GKT 55 GCE NOT Available in USA*

Interesting, but it doesn't look like the Bosch GKT 55 GCE is available in the USA. So, I guess I wouldn't include it in my selection list.

Eric


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## FrankC (Aug 24, 2012)

In brief:

Depends on what will you be using it for, sheet goods or solid wood.

Not necessary for sheet goods, the kerf on solid wood may close up so it could be a benefit.


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