If you don't have a riving knife on your old table saw

[tvrgeek]

Best option is to make a set of ZCIs for each common blade height. One with the blade set for 1/4 stock, 3/4 etc. That way you can glue in a splitter right behind the blade with no more than 1/8 clearence. You can make them for thin and thick kerf blades. If the splitter is wood, easy to trim just raising the blade. I went the expensive route upgrading from old contractor saw to newer cabinet saw. Not an option for everyone I know. I use a feather board to hold stock against the fence when I can that reduces the tendency for a push stick to skew the stock.

Please, never do a through cut without a riving knife or a splitter no more than 1/8 inch behind the blade. All that "been doing it for years" are exactly the largest group of folks with serious accidents.

Of course, a few horror stories can often convince the house "boss" that a nice new PCS is cheaper than the inevitable accident and a real necessity. They are called accident's after all. Excluding the Darwin Principal as there is no known prevention for that other than letting nature take it's course.

 

[Tarhead]

...or you could get/make different height splitters and install the hardware from Sharkguard to create a quick change bracket. This one is for thin stock. Takes about 15 seconds to change out to a different height splitter and replace the insert:

 

[tvrgeek]

WAY to far back. Maybe better than nothing but but does not solve the short piece danger. This is exactly what I was talking about to make the splitter within 1/8 inch of the blade. Not the height, the distance to the back of the blade. Matching height is of course good too. If I was going to make one for the mound as above, it would be aluminum or maybe FG sheet. Something that if you made a height mistake would not destroy the blade. Hitting steel will send carbide shrapnel your way.

Sharkguard mount was only for some older Delta's I think.

 

[Tarhead]

Sharkguard mount was only for some older Delta's I think.

That version is called the Shorty. Newer versions have a long slot milled into them to allow the height adjustment.

Riving Knives and Splitters – Shark Guard

Custom built riving knives and splitters designed for compatibility with the SharkGuard table saw blade guard and dust collection system.

www.thesharkguard.com

 

[tvrgeek]

Again, it is closeness to the blade that matters. Height only needs to be enough to engage the work. That does look like an improved version.

 

[golfdad]

I have the Shark Guard. Installed it after a severe kickback in 2008

 

[Rwe2156]

Many older saws don't have a way to install one. I got by with the Micro Jig system on my old Jet.

In addition to a riving knife, board guides are also a safety feature. I've never used one in my life but got the Jessem set for Christmas. I wish I had them all these years mainly for sheet goods.

 

[tvrgeek]

Micro Jigs work, but are a pain to install. Much easier just to stick a thin slab of engrain in the slot of a ZCI. Perfect alignment. Slightly taper and sand. My suggestion is to make multiple ZCIs with the splitter closer to the blade for each common blade height. If you set up a splitter for full height, as in the Micro-Jig instructions, then for cuts with the blade much lower, the splitter is far enough back a small piece can still skew and kick back. This I know the hard way! After all, one usually has a bunch of ZCIs anyway. I never did but I bet you could do one for 45s as well.

Been thinking about the Jessem set. Probably should. I have it where I can add and remove things to my fence quickly. I had Rip-Straits on my RAS and they helped a lot. Similar function.

For those who think the pawls on blade guards prevent kick back, think again. They can just get mangled.

 

[iclark]

Lots of good info. Thanks.

To this, I would add a reminder to never do what one manufacturer says in their ads with TSs: "We stand behind our work."

 

[areevesnc]

I’m reminded of a possibly apocryphal marketing slogan I heard years ago: John Deere stands behind every piece of equipment they ever built… except their manure spreaders.

 

[Rwe2156]

Brings up a point I‘ve thought about. I used a table saw with no splitter for well over 10 years and I can’t remember any board pinching enough to cause an issue, or at least one that caused a close call, certainly not an injury. Don’t get me wrong, I‘m not saying they aren’t necessary, b/c today I wouldn't buy a saw without a riving knife.

What I’m saying is I always felt the main purpose of the MJ splitter was to keep the wood past the blade in contact with the fence, not keep a board from binding. That just rarely if ever happens, at least within 6“ of the blade it would have to be a board with unbelievable internal tension.

Or maybe that’s the same thing a riving knife does? I dunno, a riving knife has a little flex doesn’t it? I think that’s where the guides come in.

 

[tvrgeek]

If you have soooo much tension, it will probably bind. I have only had that with a too green 2 x 4. I used to keep a couple shims handy so if I see the gap closing, I can back out a fraction and stop, stuff in the shims and then power back up. The easiest way to never have that problem is as I have done: Rip any sketchy work on the band saw. A proper knife or splitter close enough to the blade should prevent the back side of the blade teeth catching the wood and kickback. Knives are usually pretty stout. Way more than a MJ splitter. Most kickback is not pinching but the work getting skew from the blade so a back tooth catches it. We really should never be running sketchy wood through a table saw to begin with. Flat, stable, and dry. A cupped or twisted board is just begging for an accident. It takes so little time with a scrub plane to prevent problems even if you don't have a jointer and planer.

The MJ splitter does keep you to the fence, but that is exactly how you prevent kickback. Of course, proper push block bias or Jessem guides will also help keep against the fence. I use a feather board before the blade on most rips which helps as well. Just changed from an old orange plastic feather to the funky green foam fingers and am quite impressed.

As I have to keep saying, BOTH my close calls were with a rear over the table splitter and a thin short piece that either did not reach the splitter or went under it. So, real riving knife that retains it's relationship to the blade at all heights and angles I consider mandatory.

The other common kickback causes is stupidity, clearing the work while the blade is still spinning or cutting the cheek of a tenon without a clamp in place fence jig.

 

[tvrgeek]

How is this for irony:

From the Katz-Moses mail list is his video on kickback, but then a "safety kit" that includes what I think is the most dangerous push stick ever, the hard plastic ones. If it slips, instead of being cut with no effort like my standard 2 x 4 blocks, it grabs and shatters.

 

[bowman]

We really should never be running sketchy wood through a table saw to begin with.

I've had a couple of instances where kiln dried white oak bound on the riving knife. It's hard to know if wood is sketchy beforehand.

 

[bowman]

How is this for irony:

From the Katz-Moses mail list is his video on kickback, but then a "safety kit" that includes what I think is the most dangerous push stick ever, the hard plastic ones. If it slips, instead of being cut with no effort like my standard 2 x 4 blocks, it grabs and shatters.

Agreed. The plastic one from SS shattered on me, it was almost a pants changing event.

 

[Keye]

I have been waiting for someone to ask and it has not happened so what is a ZCI?

 

[bowman]

Zero clearance insert

 

[JMcanoe]

Another endorsement for the Shark Guard. Used a blade alignment tool to make sure it was properly installed. It can be set below the blade height so it can remain in place when cutting dadoes.

 

[Canuck]

Another endorsement for the Shark Guard. Used a blade alignment tool to make sure it was properly installed. It can be set below the blade height so it can remain in place when cutting dadoes.

Jim
What saw are you running it on? (I have the a Craftsman zipcode saw - 22124 and seriously thinking about it. )

 

[JMcanoe]

Jim
What saw are you running it on? (I have the a Craftsman zipcode saw - 22124 and seriously thinking about it. )

It's on a 3 hp Delta left tilt Unisaw with Biesmeyer fence - not that old, but one of the last ones made in the US. Purchased the Shark Guard splitter around 2007. Didn't get the full guard - just the splitter - because I am using a Brett over-arm guard