Thread: Tablesaw technique - ripping long timber at 45 °

I have not had a driving riving knife on my saw for about a decade. I don't advocate it and don't let others use my saw.

That said
1) hand saws don't have a riving knife

2) extremely few hand held circular saws have a riving knife

3) my jig saw does not have a riving knife

4) my reciprocating saw does not have a riving knife etc etc

I removed my knife originally because it did not lower enough to run a groove in a board without fouling.

Due to the speed of the spinning blade you might be more inclined to get kick back though ive never had that issue. The greatest risk IMHO is if there is much internal tension in your timber and it closes up on the blade as you cut. Even then i personally have not had kick back but have had the timber close up on the blade and stop the saw.

Like said ... new blade

Also double check the blade remains true to the fence when laid over. Some saws drop to the fence at the far end under their own weight

On another another note i might ask if you need 35 mm for French cleats? Would 19 do the job.

Like others i would keep the fence on the right.

Dave TTC
Turning Wood Into Art

Thanks for all the advice and suggestions, i feel more confident in proceeding.

I'll keep the saw guide/splitter on - I'm too old to learn base 9 arithmetic.
I'll need to make up an additional fence so I can keep the splitter but looking at the current fence, I'd need to do that anyway as the casting on the front part of the fence prevents a board from sitting either flat on the table or square to the fence. It's the white/scratched area just above the indicator pointer.

hi Dave to respond to your observations

Originally Posted by DaveTTC

That said
1) hand saws don't have a riving knife -- not relevant

2) extremely few hand held circular saws have a riving knife -- True, but not really relevant as most circular saws are designed for cross cutting.

TRACK saws are specifically designed for ripping and nearly every one -- Festool (yes), Makita (not sure), Triton (yes), Mafell (yes), DeWalt (yes), Grizzly (yes) -- has a riving knife. Tells you something ??

3) my jig saw does not have a riving knife -- not relevant. A jig saw has an up and down cutting action, if the blade jams, it will bend and/or break DAMHIKT

4) my reciprocating saw does not have a riving knife etc etc -- not relevant, see Jig saw

Why do you use riving knives, splitters & blade guards??


In industry these days with the focus on safety and compliance there are a number of guides on machinery guarding and equipment safety and codes of practice available. The codes of practice are to be considered mandatory in most jurisdictions, so in industry you would have to have a very good explanation on why your method is safer than those recommended in the code of practice, especially if there is an injury or compo claim.


Why is this relevant to hobbyists? Industry gains knowledge and experience faster than a collective of hobbyists with best intentions - so why not leverage off the commonly available industry knowledge!


Most codes of practice will have words similar to these "All table saws must have a hood guard, splitter, and anti-kickback device installed. One or more of these devices may be removed ONLY if absolutely necessary to perform a specific cut (e.g. dado or rabbit) and only with the approval of a shop supervisor. These safety devices must be re-installed immediately after completing the cut(s)."


GORE Warning ! If you aren't too squeamish go have a look at this site Table Saw Accident Pictures - That's why you should follow recommended codes of practice as a hobbyist!

Edit - not sure what is happening to this post as it does not display as intended - missing some text for some unknown reason - should read "All table saws must have a hood guard, splitter, and anti-kickback device installed. One or more of these devices may be removed ONLY if absolutely necessary to perform a specific cut (e.g. dado or rabbit) and only with the approval of a shop supervisor. These safety devices must be re-installed immediately after completing the cut(s)."

Originally Posted by ian

hi Dave to respond to your observations

Would i be right in assuming from this that the riving knife, used in ripping situations, is there primarily for potentional tension in the timber which may cause it to bind on the saw?

Dave TTC
Turning Wood Into Art

Originally Posted by DaveTTC

Would i be right in assuming from this that the riving knife, used in ripping situations, is there primarily for potentional tension in the timber which may cause it to bind on the saw?

Dave TTC
Turning Wood Into Art

Dave the riving knife performs a couple of functions - to help prevent a cut closing up (released tension) and binding / jaming on the rear of the blade - causing a kick back; and when used with a correctly set up fence prevents contact with the rear of the blade from wandering fingers at least on the fence side of the cut; but its most important function imo is to prevent rotation of the rip or the stock onto the rear of the blade, causing the work piece to climb up over the blade which is the primary cause of saw kick back.

Rotation of the work piece can occur with ripping and crosscut operation on the table saw.

I rip a lot of small square sections using a Microjig GRR Ripper which requires the removal of the blade guard - not something I generally approve of - but it is a case of weighing up the hazards, risk, options and making an informed choice on risk / probability. Riving knives / splitters have a proven track record in minimizing kick back events. Unfortunately the combined splitter g/ blade guard support is fixed on my saw however it allows the GRR Ripper to pass with sufficient clearance so it always remains in place on my saw except for the few dado style cuts I occasionall perform.

To minimize risk of injury and to improve certainty of product I also use a lot of sleds with appropriately placed toggle clamps - purely to eliminate any movement of the often small stock I use. Lots of options available for cutting small stuff on a table saw, not so many good ones for thin or bevel ripping though.

Ive never had kick back in over 25 years of trade use as a carpenter and Joiner either on the job or at home using a tabke saw.

As stated in my op i neither advocate or promote use without a riving kife though it has been my casr for abiut the last 10 years on my portable table saw.

Again I would not be comfortable letting anyone else use this saw as I am aeare of potential danger for someone partucularly if they are not proficient in using a tabke saw

The only issues ive ever had is with short stock or thin stock where a zero clearance insert has not been used

A firm believer 'if you dont feel safe ... dont do it' there are few second chances

Dave TTC
Turning Wood Into Art

Originally Posted by DaveTTC

Ive never had kick back in over 25 years of trade use as a carpenter and Joiner either on the job or at home using a tabke saw.

Dad was a general / house builder and I spent a lot of my youth and early 20's working along side Dad, virtually completing an extended apprenticeship, using mostly a large DeWalt radial arm docking saw and the general run of the mill power tools. A lot of that time in the 1970's & 80's was spent using a 2" trenching head on the DeWalt to cut housing in top & bottom plates for wall frames in one pass. Serious stuff!

So I gained a healthy respect for power tools & machinery from an early age and to this day I have never received an injury from a power tool, other than a minor scrape here or there & mostly on the wood lathe or belt sanders. I aim to keep it that way. Plenty of near misses though, and a number of minor injuries from hand tool slips.

I think we are the lucky ones because we have that background. However a lot of others don't so we have to be very mindful about how all the little tips we have picked up along the way and how we sense when to back off on a cut etc keeps us safe.

Unfortunately I have seen or have had people close to me suffer some very nasty injuries though, like all digits on one hand taken off while ripping with a RADS; plenty of meat taken off a thigh with an electric planer & countless injuries from angle grinders, electric drills - even an embedment deeply into the skull, of a drill bit with drill still attached - from a corded electric drill left on top of a 2 m step ladder. Bad things happen to people who are casual about safety.

Well put Moby

Dave TTC
Turning Wood Into Art

Originally Posted by DaveTTC

Ive never had kick back in over 25 years of trade use as a carpenter and Joiner either on the job or at home using a tabke saw.

What timbers are you working with?

We go through a lot of American Oak at work; that stuff does NOT behave well when ripped and you definitely know about it when it binds on a 10hp rip saw. There's a big, flat-head screwdriver permanently sitting on the outfeed end for whoever is tailing out to wedge the back end of the cut open.

Have not worked with any american oak since the late 80ies.

Other than various composite materials my work has been mostly with Aussie hard woods, pine and Oregon.

Worst piece of wood full of internal tension was a bit of 90 x 70 pine. Was steaigh as before it was quartered.

Some hard woods have stopped the blade but did not get kick back.

Dave TTC
Turning Wood Into Art

Originally Posted by DaveTTC

Some hard woods have stopped the blade but did not get kick back.

I guess that's a built-in safety feature of portable saws; when they run into trouble they just stop

I've also had some grief with 2" pine on occasion, but Oak is by far the worst.

Does your 10hp have a riving knife? I've seen some with and some without and if it does, do you still wedge?

Originally Posted by Lappa

Does your 10hp have a riving knife? I've seen some with and some without and if it does, do you still wedge?

It absolutely does have one and yes we do still wedge to make life easier for whoever is feeding.