Need some help with my table saw...

[MR H 91]

Hello all,

I need some advice. I'll start by saying woodworking is a hobby and I'm by no means a professional. Yesterday I was ripping some Sapele using my table saw when the offcut suddenly kicked back. This was a pretty scary experience, it all happened quickly and luckily I was using a couple of pushsticks, one to push the stock against the fence and the other to push through the blade. My question is, why did this happen and how do I prevent this from happening again?

My thoughts are the stock wasn't completely flat so it binded on the blade. I know my fence is true to the blade so I doubt its the fence. I was ripping 120mm stock to roughly 30mm. The 30mm piece was to the left of the blade and this is the part that caught the blade and almost hit me. Should I have had more stock to the left of the blade rather than more against the fence? I was using the riving knife, I pushed the stock at a steady speed and at a constant pace. This all happened once the cut had passed right through the wood.

Any advice would be much appreciate, this has really knocked my confidence in my ability to be safe in the workshop.

Thank you

 

[kevinlightfoot]

I think the push stick you were using to keep the stock pushed against the rip fence caused your problem,you inadvertently kept a little pressure on it when the cut was completed.This would let the waste piece move into the upcoming teeth of the blade which would catch Th timber and throw it up violently towards you ,try using just the one push stick.

 

[custard]

Did your fence extend right past the blade?

When ripping solid wood I extend the fence to slightly before the centre of blade, no further. The published advice of the HSE is to extend the fence to the first gullet, but a workshop where I once worked got into a correspondence (which I saw) with the HSE and they accepted in writing that it's okay to extend the fence to any point between the first gullet and the arbour.

 

[MR H 91]

I think the push stick you were using to keep the stock pushed against the rip fence caused your problem,you inadvertently kept a little pressure on it when the cut was completed.This would let the waste piece move into the upcoming teeth of the blade which would catch Th timber and throw it up violently towards you ,try using just the one push stick.

Thank you, looking back, this seems the most probable cause.

 

[skipdiver]

I think the push stick you were using to keep the stock pushed against the rip fence caused your problem,you inadvertently kept a little pressure on it when the cut was completed.This would let the waste piece move into the upcoming teeth of the blade which would catch Th timber and throw it up violently towards you ,try using just the one push stick.

Thank you, looking back, this seems the most probable cause.

Seems the most likely to me too. Worth noting the post by custard as well if you have got your fence full length for ripping as this can cause kickback too.

 

[kevinlightfoot]

If it was the fence causing the problem I think it would have been the piece closest to the fence that picked up and flew back at you.

 

[PAC1]

I agree with Kevin. One question how long was the piece you were cutting?

 

[lurker]

I always stand to the side of the table because no matter how careful you are with doing the right thing sooner or later......

 

[johnnyb]

Hi
I've not posted on here for long time but had to say sorry about your kick. Try and make a long pushstick if you can and use it on its own. When I first started woodwork I used a pushstick like a 350 mm stick with an angled birds mouth in the end. They work OK I then swapped to a pushstick made from a 12 mm price of ply with a handle that sticks up(above the blade) with a flat section that contacts the wood and a a small nib at the back to engage the back of the wood. This allows great control and confidence during cutting and also allows thin stock to be sawn with control. PS only push between blade and fence the offcut must be free to do it's own thing! This is more difficult to achieve with a 1/2 sheet of ply btw.but 1/2 way through the cut the pressure must shift to the piece between the blade and fence is away from the offcut. Real kickbacks(twisting the actual cut piece into the back of the blade) are mostly prevented by a good riving knife.
Jb

 

[Bodgers]

Hello all,

I need some advice. I'll start by saying woodworking is a hobby and I'm by no means a professional. Yesterday I was ripping some Sapele using my table saw when the offcut suddenly kicked back. This was a pretty scary experience, it all happened quickly and luckily I was using a couple of pushsticks, one to push the stock against the fence and the other to push through the blade. My question is, why did this happen and how do I prevent this from happening again?

My thoughts are the stock wasn't completely flat so it binded on the blade. I know my fence is true to the blade so I doubt its the fence. I was ripping 120mm stock to roughly 30mm. The 30mm piece was to the left of the blade and this is the part that caught the blade and almost hit me. Should I have had more stock to the left of the blade rather than more against the fence? I was using the riving knife, I pushed the stock at a steady speed and at a constant pace. This all happened once the cut had passed right through the wood.

Any advice would be much appreciate, this has really knocked my confidence in my ability to be safe in the workshop.

Thank you

I find having the guard on helps to prevent pieces that climb the blade and then kick back. The pieces get held down before they have chance to get thrown up and gain speed.

I would just always keep an eye on what the offcut piece is doing - especially as you have completed the cut and are turning it off - is this when it happened?

If you have thick pieces of timber that have lots of it internal tension I find rough cutting them on the band saw first is much safer (and less wasteful) and then I do the final sizing cuts (that involve less material) on the table saw.

If you were using two punch sticks, I suppose this could be caused by pinching the blade by putting pressure either side of it. I sometimes use two sticks, but the stick on the left side I only use to push down towards the table to prevent the scenario you had.

Scary though, I have had a few pieces that broke off around knots that have flew back at me and it wasn't nice.

 

[andersonec]

How close to the blade was your riving knife?

Andy

 

[Steve Maskery]

I've had two kickback accidents in my TS career, the first was after I'd had my first TS just a couple of days. I had no idea what I was doing, no instruction and there was no internet in those days either. I was doing something stupid without realising it was stupid and I got hit on the arm with the edge of a piece of thin plywood. I though for a moment that I had chopped my arm off. I got a lump on my arm as big as a duck egg and I still have the scar today.

The second time was just a couple of weeks ago. I was ripping some 38mm stock and a length of 38 x 38 x 1200 ended up speared into the wall behind me. I am older and wiser now, and have the temerity to teach others how to use a TS, so what happened? How can a careful bloke like me get kickback?

Short fence for ripping? Check.
Properly guarded? Check.
Correct blade fitted? Check.
Properly adjusted RK? Check.
Using a proper pushstick? Check.
Standing out of the way? Check.

What happened? My phone went off, that's what happened.

I was using a second pushstick to keep the workpiece in to the fence. Usually, just as the cut finishes, I would release the second PS so that the waste can "do its own thing" as Johnny quite rightly puts it. But just at that critical moment my phone went off in my pocket and I was distracted. I think that instead of letting go with the left hand I pushed it into the blade. It is the only explanation I have, it all happened so quickly. It was scary and a reminder that no matter how old you are, and how experienced you think you are, you can still get caught out, even if you think you are doing everything properly.

Ho harm done except for an embarrassing hole in the wall.

 

[Cordy]

Naughty Mr H (hammer) (hammer)
You haven't read your TS manual

A novice myself but I can tell you that you should only use 2nd push stick to get wood up to the blade

......pushsticks, one to push the stock against the fence and the other to push through the blade

This all happened once the cut had passed right through the wood..

There are many good instructional YouTubes etc to study before you start sawing again

:deer :deer Good luck and Happy Christmas :ho2 :ho2

 

[Steve Maskery]

And there are many very dangerous ones, too!

 

[andersonec]

I think this one explains a lot, worth a watch....

http://www.dailymotion.com/video/x7d2vt ... _lifestyle

Andy

 

[Steve Maskery]

I have a lot of time for Kelly Mehler. He is one of the good guys. I agree with the vast majority of what he says there. Not all, but it would be splitting hairs (as well as kerfs) to point out his small and few errors!

A Riving Knife is not the same as an American Splitter, as he acknowledges. And to say that you CAN'T have kickback if you use a RK was disproven by me just a couple of weeks ago.

It's a pity the camera didn't continue to roll, as I would have like to hear his views on short fences for ripping.

His kickback demo, which is the same as the one I filmed for my Tablesaw Safety DVD, is fine for sheet materials (although I used plywood, he's a wuss with polystyrene - though if I ever film it again I shall use polystyrene, it was a scary thing to film).

As he says, narrow ripped pieces flying back are the most dangerous, but it is wrong to suggest it doesn't happen with bigger boards. There was a case a few years ago of a lady working in a sawmill who got hit by a large kickback and was killed. OK, we don't have those sorts of giant saws in our workshops, but the point stands, I think.

That's a good link, Andy.

 

[andersonec]

I have a lot of time for Kelly Mehler. He is one of the good guys. I agree with the vast majority of what he says there. Not all, but it would be splitting hairs (as well as kerfs) to point out his small and few errors!

A Riving Knife is not the same as an American Splitter, as he acknowledges. And to say that you CAN'T have kickback if you use a RK was disproven by me just a couple of weeks ago.

It's a pity the camera didn't continue to roll, as I would have like to hear his views on short fences for ripping.

His kickback demo, which is the same as the one I filmed for my Tablesaw Safety DVD, is fine for sheet materials (although I used plywood, he's a wuss with polystyrene - though if I ever film it again I shall use polystyrene, it was a scary thing to film).

As he says, narrow ripped pieces flying back are the most dangerous, but it is wrong to suggest it doesn't happen with bigger boards. There was a case a few years ago of a lady working in a sawmill who got hit by a large kickback and was killed. OK, we don't have those sorts of giant saws in our workshops, but the point stands, I think.

That's a good link, Andy.

I have put it up a few times now Steve because it's the only sensible video I can find, there are too many "self taught" video's on youtube feeding wrong information, I also think there are a couple of things missing, one is the distance of the riving knife from the blade and as you say the length of the fence protruding past the teeth, you can tell the lack of use of riving knifes over there because one of the audience has to ask what happens if you tilt the blade with a riving knife fitted????
I was taught many years ago (at a school of wood 'machining') that the fence went just past the gullet of the teeth because once past the teeth the wood has been cut and it's the remainder against the fence which needs firm guiding, the work piece must be kept tight to the fence whilst feeding, if you ever get to the College at Newark then you will see the fences are all set at that length.

Andy

 

[transatlantic]

I also think there are a couple of things missing, one is the distance of the riving knife from the blade

Please explain!

 

[transatlantic]

And to say that you CAN'T have kickback if you use a RK was disproven by me just a couple of weeks ago.

He distinguishes between kickback and ejection, ... your case sounded more like ejection?

 

[Steve Maskery]

I would not make the distinction between the two, TBH

Regarding RK distance, he says less than 1/8". HSE standards say between 3mm and 8mm at table level. That's 1/8 to 5/16 of an inch.