# How do you stop miter saw kickback?



## Microscopes (Jan 3, 2016)

And maybe "kickback" isn't really the right word.

I am an amateur woodworker, and ever since I can remember, my miter saw will throw wood (mostly backwards - not at me) every once in a while. It usually makes a chip in the wood/cut too.

I can't figure out what I'm doing wrong that causes this to happen sometimes.

It especially happens when I'm making very small end pieces for crown molding - but it happens on longer pieces too sometimes.


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## gmercer_48083 (Apr 9, 2016)

A miter saw blade uses a negative hook angle tooth grind. If someone changed the blade, that could be the problem. The most obvious reason is that the material moves during the cut. Here is a video worth absorbing...


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## subroc (Jan 3, 2015)

What do you have for a saw? Brand and model will be helpful.

I had an incident where a small cutoff piece got wedged in the insert and launched, it traveled over 10 feet and went through a panel in the garage door and ended about 15 feet down the driveway. I am thankful it didn't hit me. A miter saw is a powerful tool.

As far as cutting and the saw launching the pieces you need good habits and proper blades. If there is a need for a zero clearance insert buy or make one. Make sure the is enough cut-off. Having a tiny piece of material as a cut-off that can get wedged in an insert, or back fence or material that isn't supported by the fence on both sides of the blades might not be safe. Be willing to have enough cut-off to create a safe cut.


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## hawkeye10 (Feb 18, 2015)

subroc said:


> What do you have for a saw? Brand and model will be helpful.
> 
> I had an incident where a small cutoff piece got wedged in the insert and launched, it traveled over 10 feet and went through a panel in the garage door and ended about 15 feet down the driveway. I am thankful it didn't hit me. A miter saw is a powerful tool.
> 
> As far as cutting and the saw launching the pieces you need good habits and proper blades. If there is a need for a zero clearance insert buy or make one. Make sure the is enough cut-off. Having a tiny piece of material as a cut-off that can get wedged in an insert, or back fence or material that isn't supported by the fence on both sides of the blades might not be safe. Be willing to have enough cut-off to create a safe cut.



That is the reason I made a zero clearance plate for my saw.


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## Toolman50 (Mar 22, 2015)

This video is so slooooow it becomes torture to watch it. 
This guy must be paid by the hour. Could be shortened by 80% and still get all the points across.


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## shoot summ (Feb 21, 2014)

As stated, let's see a pic of your saw, and fence, something isn't right...


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## Steve Neul (Sep 2, 2011)

It may be you are intimidated by the saw and not holding the wood down firmly against the fence enough.


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## Terry Q (Jul 28, 2016)

Some things that throw pieces are rate of cut, if you cut too quickly you not only get a worse cut with tear out, but can help launch your cutoff piece. Also, you are suppose to wait for the blade to stop before raising it back up.

I get small cut offs launched from time to time, but they are generally harmless. If I was trying to cut small pieces that I wanted to use, I’d use a table saw with a sled.


In woodworking there is always more then one way to accomplish something.


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## Mad (Dec 9, 2017)

Previously made points that resonate and have worked for me:

1. WAIT for the saw blade to STOP spinning before lifting carraige.

2. Zero clearance inserts help. I made a drop in insert that can be removed in one second without tools when bevel cuts are needed... so I have no excuse to use the ZCI for all cuts where the blade is perpendicular to the table.

3. Smaller thinner work benefits from thinner kerf with higher tooth count, smaller gullets, and less deviation from center tooth to tooth.


And another point I'd like to add that hasn't yet been mentioned...

4. Shop vacs or dust collection shrouds that are extended all the way down to the table at the fence line can be beneficial by not only sucking up dust, but also sucking up the small pieces that are cut off when making small cuts. I've seen many a wafer and chunk get sucked up in my shroud extension. Sometimes, the cut off ends up blocking the suction when it gets lodged somewhere inside the factory chute. That's great! Cause that means that little piece didn't launch somewhere else. I just stop cutting, pull the hose, clear the obstruction, get back to cutting.


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## Justin Huisenga (Apr 2, 2011)

To keep from tossing small parts you need to put a sacrificial block behind the piece being cut. Can be as simple as a piece of random scrap or a dedicated fixture. A zero clearance throat plate isn't gonna do much in this application. The problem is at the fence. I have a ZCI plate in my saw but it's purpose is to make lining up cuts marked on the leading edge of the moulding fast and accurate. Pics of a fixture and my insert attached.

Hook matters more than kerf. You want a negative hook. The back angle will tend to push the material down and back to the fence as you cut. Every blade I run in my miter saws is full kerf with a negative hook. Most of the time I do not use a backup block or ZC fixture when cutting small mouldings because of the hook on the teeth. 

When cutting small parts I do not use a vac hooked up to the saw. Depending on the saw the suction can grab the drops or return and suck them into the spinning blade. I've had an off cut get sucked into the blade when running a vac and the resulting kick was enough to bend both the arbor bushing and the blade clamp flange.

The most common causes of a kick is either a fence that's toed in at the blade or warped moulding not being tight to the fence. The toe causes a pinch as the blade cuts through and the warp and the movement allowed by not having the trim tight to the fence allows the blade to grab it.


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## Mad (Dec 9, 2017)

When I was describing point 4 in my post above, I was only thinking of trimming very small amounts off of larger pieces, and discarding the smaller trimmings. My intent is to keep the smaller trimmings from flying. If your intent is to keep the smaller parts for use in the project, then yes, a vacuum (without a screen) would be a problem. I have a piece of 1/4" hardware cloth (foundation vent screen) that I would use in that situation. But unlike the guy in the video, I don't do tiny small small craft woodworking. Thanks Justin, for making your (great) points that made me go back and re-read the original post again to see that the OP is trying to save the smaller pieces.


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## NoThankyou (Mar 21, 2018)

Two basic rules:
Flat on the table
Flat against the fence

On the crown molding. Use 3/4 inch Baltic birch for sleds it is best.

Make two sleds that will hold the crown molding. I prefer, right side up and at the angle it will be on the wall. Make the sleds about 18 inches to start. 

On the first sled cut the right end of the sled at 45° on the left side of the miter saw. Cut the left end of the sled at 45° on the right side of the miter saw. (The sled should look like a trapezoid.) 


On the second sled you'll make the cuts exactly the opposite. One sled will be used for an inside corner and the other for outside corners. 

Your small pieces will be off fall and at least ¾ inch from table or fence. There should be nothing to trap the pieces against the blade. The pieces should not be kicked. 

One other thing. After the cut is made, shut the saw off before raising the blade.


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## woodnthings (Jan 24, 2009)

*The thread is 2 years old ......*

Good tips above, but the question was answered long ago ..... :wink:


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