# Riving knife modification



## Karl

One thing which has always bugged me about my saw's riving knife is the way it stands proud of the blade, like this







The guard itself removes within seconds, by simply unlocking a bristol lever. But the riving knife design prevents enclosed cuts from being made - ie shoulder cuts etc.

So I decided to modify the riving knife thus






Having the top of the riving knife below the level of the blade means that I can now cut shoulders, tenons etc. 

Here is the finished shot, with the guard back in place - and my Metabo blade. Freud blade on its way to e-bay shortly :x 






There was one final benefit to this excercise - with the guards removed and the blade lowered, the riving knife is now below the surface of the table, meaning that I can pop an MDF cover over it and use it as an assembly table






Cheers

Karl


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## wizer

Nice one Karl. This is exactly what I was planning for the Jet Supersaw before I sold it. For exactly the 2 reasons you point out. Tho on the Jet you only needed to lop about 10mm off.

How are you finding that saw? Does it have a standard size mitre slot?


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## mailee

My riving knife is very similar to that one Karl. I made the slot it mounts on longer so I could lower it more. Mine also sits just below the blade and the top remains untouched to attach the crown guard. Naughty but nice. :wink:


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## Niki

Hi Karl

It's very interesting...it looks like the saw is the Metabo 200...

I have the Metabo (Electra Beckum) PK-255. The riving knife and the blade guard looks the same.
The riving knife sits normally some 3mm below the blade...maybe, your riving knife is designed for the 255mm blade but when used with 200mm blade it stays above the blade.

I changed the "Bristol lever" with a wing nut...

Anyway, nice modification...

Regards
niki


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## Digit

What I understand may simply be an urban myth, but I have always understood the reason for the 'L' shape slot is to stop the crown guard being sent flying if the wood lifts for any reason.

Roy.


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## Karl

Tom

I think the saw is great, if a little noisy. I only paid £330ish, when the alternatives I looked at were closer (or over) £500. It is also useful for me to be able to put it in the back of the car and take it on site if needs be. It seems to be about £330 everywhere now - they must be phasing it out.

Having said that, I haven't used a "proper" table saw. I don't know how it would compare to your old Jet. Not very well, I suspect. 

It takes a standard mitre bar - I use an Incra mitre gauge with it.

Alan

Didn't think about making the slots longer - good idea.

Niki

The saw is the Metabo TS250, and uses a 250mm blade. The riving knife just would not sink below the top level of the blade.

Funny you should mention about changing the bristol lever for another locking nut - I was hunting round the 'shop for one tonight. The bristol lever is a bit cumbersome for removing the blade - the lever section can catch on the table if the blade is low. I'm going to change it as soon as I find a suitable nut.

Cheers

Karl


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## OPJ

Good work, Karl, but, I do share Roy's concern and would advise you to look at extending that slot for mounting the crown guard securely... :? There appears to be plenty of room for the guard to sit lower so, that shouldn't be a problem.


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## Karl

Roy/Olly

Bloody hell - you guys don't miss anything do you.... :lol: 

The only reason I didn't extend the hole was because I had left all my drill bits (with the exception of my auger bits) on site. So I only had a large hacksaw and a round file to do the job.

Once I get my drill bits back next week, i'll be extending the hole.

Having said that - do you really think there is any chance of it being knocked off? The guard is secure to the extraction pipe via epoxy glue. Also, there is plenty of clamping force provided by the locking lever. And I doubt that timber would rise at a sufficient speed to knock the guard off anyway. 

Nonetheless - it will be done.

Cheers

Karl


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## Digit

To be honest Karl I've never known a piece of timber lift enough to be a risk, frankly I think it's a belt and braces idea.

Roy.


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## Steve Maskery

Can I ask why your Freud is on its way out? Brad said something less than comp about his Freud recently, and I've just put someone to a great deal of trouble to get me a particular Freud blade back from USA (it's installed this very day but still virgin). I've had a Freud blade for nigh on 20 years and can't fault it, hence my recent replacement, and I'm surprised and slightly concerned that people are less than delighted with their Freud purchases. I have no connection, but I'll be disappointed if my new Freud is not every bit as excellent as my old one.

S


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## Karl

Steve Maskery":119lwyp2 said:


> Can I ask why your Freud is on its way out? Brad said something less than comp about his Freud recently, and I've just put someone to a great deal of trouble to get me a particular Freud blade back from USA (it's installed this very day but still virgin). I've had a Freud blade for nigh on 20 years and can't fault it, hence my recent replacement, and I'm surprised and slightly concerned that people are less than delighted with their Freud purchases. I have no connection, but I'll be disappointed if my new Freud is not every bit as excellent as my old one.
> 
> S



Hi Steve

I purchased the Freud, really on the back of recommendations on this forum. 

It wasn't that there was anything particularly wrong with the blade supplied with the Metabo, but I thought I might be missing out on something better by not "upgrading" the blade. So I bought a combination blade, which stated that it was ideal for both ripping and crosscutting hardwood and softwood. As I have a project on the go at the moment, and a few more lined up as well, I thought i'd upgrade the blade.

As soon as I did my first cut with the Freud, I knew it was a mistake to change the blade. Rip cutting was much less comfortable than with the Metabo blade, and crosscutting wasn't as clean. Also, don't ask me why, but the dust extraction didn't seem nearly as good. Perhaps this last point was in my mind - but i'll find out tomorrow when I do some more cutting with the original blade.

I'm not dismissing all Freud blades, but this one definitely didn't do it for me.

HTH

Cheers

Karl


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## Jake

Karl":1ryvnisx said:


> As soon as I did my first cut with the Freud, I knew it was a mistake to change the blade. Rip cutting was much less comfortable than with the Metabo blade, and crosscutting wasn't as clean. Also, don't ask me why, but the dust extraction didn't seem nearly as good. Perhaps this last point was in my mind - but i'll find out tomorrow when I do some more cutting with the original blade.
> 
> I'm not dismissing all Freud blades, but this one definitely didn't do it for me.l



I've never used a Freud saw-blade, but their reputation (outside this forum) isn't all that - yes, good quality but not top-notch. Trade, rather than industrial, let's say. It is possible, Metabo being based where they are, that they purchase their stock blade from one of the true industrial makers and you were actually downgrading.

All surmise, but given Freud's place in the pecking order, it is entirely possible.


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## paulm

As Mailee says, the best way to mod the knife, if possible, is by leaving it intact but elongating the slot used to bolt it in position, allowing the knife to sit lower.

Did this on my sip for the same reasons Karl mentions and it does make a big difference being able to cover the top with a couple of pieces of thin mdf when the saw's not in use as well as cutting shoulders etc, but otherwise the guard is always refitted for safety of course.

Cheers, Paul


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## newt

I have tried different blades in my electra bekcum PK200 and nothing matches the blades that came with the saw. Perhaps I have been spoilt but my knife can be adjusted over a range of heights and there is also a scale on the knife to facilitate this adjustment. To be honest I thought most saws had this feature. Karl I see you have a curved slot (just visable) don't understand why you cannot lower yours, unless you are using a smaller diameter blade ( a bit risky as each blade is designed to operate at a certain speed) as has been suggested.


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## Karl

newt":1oq8gi6v said:


> Karl I see you have a curved slot (just visable) don't understand why you cannot lower yours, unless you are using a smaller diameter blade ( a bit risky as each blade is designed to operate at a certain speed) as has been suggested.



Hi Pete

The blade is 10", the maximum the saw can take.

The riving knife does have the curved slots in it, and you can just see one of them (there are two slots) in the second picture - I chopped a bit too much off, and had to raise the riving knife a touch. They are not visible in the first shot of the unmodified knife - because the knife was lowered as far as it would go. As you can see from that first shot, the knife was still considerably higher than the blade.

Hope that makes sense.

Cheers

Karl


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## Gower

Regarding Steve Maskery's point about Freud blades, I bought a thin kerf Freud Pro Dual Purpose blade last week replacing a CMT. I've only used it for ripping so far (100mm mahogany) and I'm delighted with it's performance. Can't wait to get out to the workshop and try out it's cross cutting abilities now!


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## Digit

I now use a similar blade in conjunction with a sled on my TS Jim and my shooting boards are no more!

Roy.


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## Benchwayze

Hmmm. I have a Freud blade for my 9" Portable saw. 

Maybe I'll send the old blade for resharpening! I was going to change it, because somehow I managed to cut part-way through the ribs on the underside of my Triton table. I don't think the blade (An Elu) even noticed it was cutting mild steel! 

Not that I shall be using any tools for a good while! 

regards
John


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## chippy1970

Karl":laiup67w said:


> One thing which has always bugged me about my saw's riving knife is the way it stands proud of the blade, like this
> 
> 
> 
> 
> 
> 
> The guard itself removes within seconds, by simply unlocking a bristol lever. But the riving knife design prevents enclosed cuts from being made - ie shoulder cuts etc.
> 
> So I decided to modify the riving knife thus
> 
> 
> 
> 
> 
> 
> Having the top of the riving knife below the level of the blade means that I can now cut shoulders, tenons etc.
> 
> Here is the finished shot, with the guard back in place - and my Metabo blade. Freud blade on its way to e-bay shortly :x
> 
> 
> 
> 
> 
> 
> There was one final benefit to this excercise - with the guards removed and the blade lowered, the riving knife is now below the surface of the table, meaning that I can pop an MDF cover over it and use it as an assembly table
> 
> 
> 
> 
> 
> 
> Cheers
> Karl



They must have changed these riving knives as my 3 yr old Elektra Bekum version of your saw has a knife that can go lower than the blade.


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## chippy1970

heres a pic of my one


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## Karl

Interesting -they may have changed the riving knife, or mine may have just been a dud. Whichever, mine definitely would not slip further down over the fixing bolts. 

Cheers

Karl


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## devonwoody

I've made the slot longer on my riving knife (axminster aw10) so the knife is usually below the top of the blade. ( I have to raise it when I want to get maximum cut depth occasionally.

However can anyone say that this modification ruins the effectiveness of a riving knife and some circumstances you will get a kickback because of the lower height of knife?


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## Krysstel

chippy1970":1am56833 said:


> They must have changed these riving knives as my 3 yr old Elektra Bekum version of your saw has a knife that can go lower than the blade.



My 2 week old TS250 also has a riving knife that, after I adjusted it slightly, goes just lower than the blade.

Karl - what do you think of the TS250 ?
I've had some problems setting up mine as I mentioned in this post
I eventially tracked the problem down to a combination of the fence rails being out of line with the blade and the sub-fence not being 90 degrees.
The rails are attached to the right hand table extension and it appears to me that if the table extension is not pushed completely to the left after use then the rip fence will not be in line with the blade. Or am I wrong ?
The sub-fence I've decided to dump and make my own accurate and better version. How was yours ?
The rest of the factory settings; blade angle, adjustment stops etc were also way off from the factory - but perhaps that's just normal.


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## Niki

devonwoody":2d55i7kx said:


> However can anyone say that this modification ruins the effectiveness of a riving knife and some circumstances you will get a kickback because of the lower height of knife?


Hi John

I think that the RK is still effective in minimizing the kickback risk (even the riving knife cannot eliminate the kickback totally...according to the Metabo engineers)...

My RK is set 3 mm below the blade level but, when I set the blade height, it's always so that at least the gulls are above the workpiece thickness - some 10~12mm (actually, I usually set the blade to "full height" but, as you know, I'm crazy  )...So, the RK is never below the workpiece level...

If you'll have a look at this PDF file
http://www.hse.gov.uk/pubns/wis16.pdf

You'll see on "Figure 5 - Riving knife fixing"
"For blades greater that 600 mm diameter, E (i.e. the RK) should be at least 225 mm above the table"....that tells me, that the RK might be below the workpiece level when cutting wood thicker than 225 mm and, if it's OK for the guys from the HSE, it's good enough for me 

Regards
niki


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## devonwoody

Thank you Niki for your comments, its a comfort to have your input.


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## chippy1970

Karl":29rd2w3p said:


> Tom
> 
> I think the saw is great, if a little noisy. I only paid £330ish, when the alternatives I looked at were closer (or over) £500. It is also useful for me to be able to put it in the back of the car and take it on site if needs be. It seems to be about £330 everywhere now - they must be phasing it out.
> 
> Having said that, I haven't used a "proper" table saw. I don't know how it would compare to your old Jet. Not very well, I suspect.
> 
> It takes a standard mitre bar - I use an Incra mitre gauge with it.
> 
> Alan
> 
> Didn't think about making the slots longer - good idea.
> 
> Niki
> 
> The saw is the Metabo TS250, and uses a 250mm blade. The riving knife just would not sink below the top level of the blade.
> 
> Funny you should mention about changing the bristol lever for another locking nut - I was hunting round the 'shop for one tonight. The bristol lever is a bit cumbersome for removing the blade - the lever section can catch on the table if the blade is low. I'm going to change it as soon as I find a suitable nut.
> 
> Cheers
> 
> Karl



I dont think they are phasing them out. I payed £499 for my EB TS250 but that did come with a stand and dust extract pipes, the price has just dropped by a mile which makes a change for a tool price to come down :lol:


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## Tim Nott

I did a similar thing with my Robland combi

The original knife had a hole, rather than a slot at the top, which made it a PITA to remove the guard, so I filed this to a slot - it isn't L-shaped, just straight, but I've never had it come off in 4 1/2 years. I later filed the lower slot so the RK could be lowered beneath the blade for those naughty but nice 'not-all-the-way-through' cuts.


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## Steve (Correze)

Hmm... interesting, the riving knife on my SICAR combi has both a L-slot and a hole to attach the guard. The guard has a fixed pin which goes in the slot and a Bristol lever which screws through the hole. The whole assembly is mounted on a parallelogram so that it follows the blade as the height is adjusted (the blade pivots about it's front edge rather than the arbour) and always remains level with the top of the blade regardless of height. To use the full height of the blade, you need to remove the guard, but I'm considering converting to a SUVA type, using the support arm for the planer guard which is perfectly placed.

The riving knife on the works Casadei saw also runs to the full height of the blade (500mm blade), though in this case there is no guard attached as it has a SUVA type guard.


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## FatFreddysCat

Niki":1hkddmxc said:


> "For blades greater that 600 mm diameter, E (i.e. the RK) should be at least 225 mm above the table"....that tells me, that the RK might be below the workpiece level when cutting wood thicker than 225 mm and, if it's OK for the guys from the HSE, it's good enough for me


Niki, just bear in mind that a 600mm blade generally has something like a 4.5 to 5mm kerf and that a 26in rip saw often has a depth of cut of around 8 to 9 inches (i.e. 200 to 225mm), so the riving knife will be almost as high as the blade in most cases. You don't often see saws bigger than 26 inches these days.


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## liam8223

I have a wadkin 12" AGS and my riving knife is massive- all to fit the crown guard.

I have been pondering chopping it, after a lot of advice from fellow woodworkers, but now i have seen yours, i will be removing and chopping forthwith!

Also if anyone requires a truly 'multipurpose' blade I cannot recommend my GOMEX blades enough!

I bought my latest one and was dubious at first as to wether it would rip large stock easily -- It does!

And the finish whilst ripping is fantastic, very smooth.

The blade that came with my saw was a 30 tooth rough looking thing, but on its return from the sharpeners, it also is a Gomex, and i had been using that for ages with no complaints.

I have a good supplier of these blades, if anyone wants the name/number, pm me.


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## devonwoody

liam8223":3oxav469 said:


> I have a wadkin 12" AGS and my riving knife is massive- all to fit the crown guard.
> 
> I have been pondering chopping it, after a lot of advice from fellow woodworkers, but now i have seen yours, i will be removing and chopping forthwith!
> 
> Also if anyone requires a truly 'multipurpose' blade I cannot recommend my GOMEX blades.
> 
> I bought my latest one and was dubious at first as to wether it would rip large stock easily -- It does!
> 
> And the finish whilst ripping is fantastic, very smooth.
> 
> The blade that came with my saw was a 30 tooth rough looking thing, but on its return from the sharpeners, it also is a Gomex, and i had been using that for ages with no complaints.
> 
> I have a good supplier of these blades, if anyone wants the name/number, pm me.




http://www.applegate.co.uk/all-industry ... 082525.htm


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