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William Addison
11-15-2006, 8:49 PM
I recently read a post, possibly here, in which a man was hit by a kickback because his dust collectior caused a quarter inch piece of plywood to lift and contact the blade.

Yesterday afternoon a close friend who has many years of accident free experience with a table saw had an accident that may cost him his middle finger, and had his ring and little fingers seriousy cut. He was ripping a piece of Walnut about three inches wide and thirty six inches long and was using a push stick when the offcut side of the stock flew back and struck him in the lower stomach causing him to flinch and lean forward, the hand holding the push stick dropped and contacted the blade.

I have had a few kickbacks but never on the offcut side and he has mentioned having several in spite of his being very safety conscious.

It doesn't seem plausible but does anyone think it's at all possible the vacuum from the DC may be involved in this?

Jim Becker
11-15-2006, 8:55 PM
I can't comment on the DC situation...never had that problem with my overarm guard, but ALL of the kickbacks I have ever experienced were on the off-cut side of things.

Ben Grunow
11-15-2006, 9:02 PM
Offcut kick back? Never even imagined it. The only kicks I have ever had are form bowed stock getting stuck between the blade and fence (sent a few throught the drywall on the job). How does an off cut get caught by the blade and thrown?

Phil Pritchard
11-18-2006, 7:25 AM
This only serves to underline the need for a riving knife and crown guard on saws. Was your friend using either of these?

William Addison
11-18-2006, 8:16 AM
He was using a Bisemeyer splitter, the antikickback pawls obviously didn't work.

Mark Singer
11-18-2006, 9:44 AM
Something does not seem accurate....he didn't push all the way through , probably. The cut of side next to the blade will just sit there or move very slowly back...the larger the cutoff the less chance of it going anywhere.

Frank Fusco
11-18-2006, 9:54 AM
Offcut kick back? Never even imagined it. The only kicks I have ever had are form bowed stock getting stuck between the blade and fence (sent a few throught the drywall on the job). How does an off cut get caught by the blade and thrown?

I had a an offcut kick-back with my table saw that taught me important lessons. Actually, others on a discussion forum told me what I did wrong and how it happened.
I was cross-cutting a 2x4 using the fence as a guide and standing in direct line with the blade.
Keep in mind, I was a beginners-beginner. About all I knew was to keep my hands away from the blade.
The off-cut section came back and hit me in the solar plexus like a cannon shot. It put me down on the floor for about fifteen minutes. I don't know if I passed out, but came very close.
No more cross-cut with fence and now always stand to the side, not in line with blade.

William Addison
11-18-2006, 11:23 AM
My understanding is that the kickback happened after the stock was ripped all the way through and he was completeing the cut by pushing the piece between the blade and fence through.

He has used a table saw for over thirty years and is one of the most safety conscious people I know. He's tall and while the kickback didn't injure him he says that he has a bruise in a most unfortunate location.

Bob Dodge
11-18-2006, 12:08 PM
I recently read a post, possibly here, in which a man was hit by a kickback because his dust collectior caused a quarter inch piece of plywood to lift and contact the blade.

Yesterday afternoon a close friend who has many years of accident free experience with a table saw had an accident that may cost him his middle finger, and had his ring and little fingers seriousy cut. He was ripping a piece of Walnut about three inches wide and thirty six inches long and was using a push stick when the offcut side of the stock flew back and struck him in the lower stomach causing him to flinch and lean forward, the hand holding the push stick dropped and contacted the blade.

I have had a few kickbacks but never on the offcut side and he has mentioned having several in spite of his being very safety conscious.

It doesn't seem plausible but does anyone think it's at all possible the vacuum from the DC may be involved in this?

Hi William,

That's an interesting situation. If your friend cut his fingers, then there was no overarm blade-cover on his saw; correct?. The dc would only be collected to his saw-base, right? I'd also have to assume he wasn't using a zero-clearance insert; do you know if that is the case?

In order for the dc to draw the off-cut sideways into the blade, there would have to be a lot of airflow between the blade and the off-cut, or, possibly at the gap behind the blade. This could cause the off-cut to twist slightly, disengaging the off-cut from the kick-back pawls on the splitter. With a 24 tooth rip-blade, I can see where a tooth may have caught the off-cut, and started propelling the off-cut forward. Was he handling the off-cut when it happened? Was he clearing it away with his left hand? Could that motion have caused the off-cut to rotate slightly?

From what I gather, the impact from the off-cut startled him more than anything else, so that wasn't a violent impact; correct? I'm just trying to understand if , or how, the dc could have been involved in this incident.

I have seen a pic posted where the operator uses an Excalibur overarm blade-guard, and a piece of wood is drawn upward into the guard's hood. Fortunately for him, that piece was quite short and narrow, and stayed wedged inside the overarm blade-cover's hood. The tail-end of that piece had lifted toward the oa-bc's 3" port. That piece was shorter than the diameter of the blade.

I have had incidents where a very thin off-cut from a rip operation, get's thrust forward, but that's usually a very gradual acceleration forward, not a sudden impact. When that occurs, I have noticed that there is a gradual but steady increase in that acceleration. There's really nothing to cause the piece to bind and get thrust forward violently; just a light "brushing' against the side of the blade. Could a similar event have happened to your friend, causing his first instinct to tell him "kick-back", and he over-reacted, and his focus was not on his right hand? A very thin off-cut would not necessarily be engaged by the splitter-pawls, and the dc's suction, may have kept that piece over the insert-slot,against the blade, propelling it forward quite rapidly. That would be very doubtful though, if he had a ZCI. Perhaps you fellows should re-examine that off-cut, and the throat-plate.

Bob

Gail O'Rourke
11-18-2006, 12:52 PM
Such terrible news...my question would be what was there for an outfeed table? If the offcut dipped down when exiting the back end of the table, I could see where it would turn and come to rest on top of the blade - then kicking back - or if it got hung up somewhere on the outfeed table - and made a slight turn into the blade.

William Addison
11-18-2006, 4:50 PM
He was using a WWII blade and the standard Unisaw insert for improved dust pickup from an Oneida DC. His outfeed table is the one made for a Unisaw and is level to the saw table. His left hand was no where near the saw and he was using a commercail pushstick. The offcut was thrown hard enough to bruise his "parts." I think saying it startled him is an understatement and the resulting flinch is what caused the downward movement of his right hand into the blade. I don't know what all the causes could be but a DC of that sort produces so little air pressure I can't imagine that as a factor but I can't think of anything else.

Tom Jones III
11-20-2006, 10:27 AM
It sounds like if he was using a blade guard it would have absorbed most or all of the force of the kickback. I know my excalibur would have done so.