# Kick back on router table



## SpikeJ (Feb 28, 2011)

Today I had kick back on router table. I am wondering what is the cause of this kick back. 
This is the first time for me to use trim bit(whiteside#2715 which has 1-1/2 cutting length and 7/8 cutting diameter with top and bottom bearings). I cut the work piece by band saw roughly and tried to trim it by using this bit with template.
I slowed down the speed of router to 10,000 rpm because this bit was quite big trim bit.
The thickness of work piece was about 3/4. As soon as the work piece touch to the bit, the kick back happened and
work piece flied to the right side. The difference between the template and the work piece was about 1/8.
I am not sure that I feed the work piece in climb cut direction, because the kick back happened as soon as the bit touched
to the work piece. My assumption to the cause of this kick back is I tried to cut too much at once. ( as I mentioned the amount to be trim was 1/8. ) If my assumption is correct, how much is the ideal(safe) amount of one cut?


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## HerbC (Jul 28, 2010)

Try using a starter pin. This give you a point to steady the workpiece when beginning your cut.

Good Luck!

Be Careful!

Herb


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## Loren (May 30, 2008)

Such trimming cuts require a lot of control. The bit can take too big
a bite and catch on the wood.

I sometimes make a flat jig with the template attached to it and put
two solid handles on the jig. You have to have really positive control
of the workpiece to make trimming cuts with those long pattern bits
on the router table.

Starting pins are also very useful for beginning this type of cut successfully.


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## patron (Apr 2, 2009)

a starter pin can be a bolt in one of the threaded holes for just that purpose
or i have just clamped a block of scrap of wood
(with rounded corner) to the table
on the in-feed side
not to close for more control
the idea being to put the work to the 'pin' first
and slowly feed it over to the cutter with bearing
holding it to the 'pin' till the cutter is doing it's work
and the pattern is snug to the bearing
as you advance the work to the cutter
ease away from the 'pin'
and work the pattern forward against the bearing
being in control
as stated above

don't be shy holding the work solid to the bearing
but hold your hands safely away from the cutter action
and if you remove the work
always use the 'pin' to return to the cut again


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## CharlieM1958 (Nov 7, 2006)

I agree with David and Loren. !/8" is not too much to remove at once…. it's starting the cut that can be tricky. A starting pin is good, as mentioned. You can do this cut successfully without one, but you must approach the bit very slowly, and with a good grip. Once the cut is started, and your pattern is tightly against the bearing, you can increase your feed rate without a problem.


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## greasemonkeyredneck (Aug 14, 2010)

When using this type bit, I am always careful to make sure to have a good hold of the work piece. I make sure to wear gloves, because large chunks of wood in your hand hurt like hell (yes I know this from experience). Then I make sure my body is out of the way that the wood will most likely fly if it decides to do so. I have done what you describe to several boards at a time with no problem. Then all of a sudden for no apparent reason, it'll catch one wrong. I actually had it happen one time and it threw the board across the shop at great speed, right through a window.


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## SpikeJ (Feb 28, 2011)

Thanks for your advises. 
I tried this work again today. I hold the work piece against the starting pin and slowly let the work piece closer to the trim
bit. Fortunately first several cuts were successful. However after several cuts, I had a kick back again. It look like the bit took a bite too big. I used GRR-ripper to hold the work piece, so my fingers were safe.
At this moment this kind of big bit is very scary for me and need a lot of control. I learned that free holding routing on router table is a kind of very tricky and difficult task. I may try smaller size trim bit for my practice or will make the 
well work piece holding fixture.


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## Wiljoy (Jan 13, 2011)

I'm sorry but I have to disagree with William regarding wearing gloves, I was in the woodwork trade for over 50 years and now at 86 I run a woodwork shed in a retirement village and I must say there are VERY FEW OCCASIONS where gloves should be worn when using machinery of ANY description you do not have enough control of your workpiece with gloves on so I would tell ANYONE not to wear gloves in a workshop. NEVER,NEVER,NEVER.


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## MrUnix (May 18, 2012)

I think your speed is too slow - 10,000 RPM is suitable for something like a 3" bit, but way too slow for one under an inch.

Cheers,
Brad


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## Kazooman (Jan 20, 2013)

Are you starting the cut in the middle of one of the edges or are you jamming a corner of the workpiece into the bit? The bit can really catch on a sharp corner with bad results. Ease the bit into the side of the workpiece just short of the leading corner and then feed it along. Depending on just what your work looks like you might need to do a very small climb cut to finish the leading end. If you can continue on around the piece you won't even need to do that.


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## rwe2156 (May 7, 2014)

You might be starting the cut against the grain.
Fluted bites are bad about gouging out a chunk of wood if grain direction is wrong.
I agree with Brad, jack up the RPM's and try again.
Even if the grain direction is fighting the bit, higher RPM's can eliminate the issue.

*However* my recommendation is use the router fence.
I find this works best and is the safest way to go, even with bearing bits.
I rarely ever use a pin anymore.


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## hairy (Sep 23, 2008)

It sounds to me like you went the wrong way with your cut. I move from right to left on a router table.

http://www.newwoodworker.com/rtrfeeddir.html


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## wapakfred (Jul 29, 2011)

I agree with several points made earlier: the starter pin (if it's a curved piece the fence won't help, but it would be better for a straight trim), less bite is always good (though I don't really consider 1/8" on a 3/4" piece too much), check the grain of the wood, and speed the router up to a halfway speed (~15,000 rpm). I do disagree (a lot) with the gloves suggestion….good luck with your effort.


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## rwe2156 (May 7, 2014)

I use gloves all the time when planing rough wood.
I wouldn't use them with a drill press or tablesaw, though.

Perhaps Wiljoy could explain more what the issue is.

I certainly respect the opinion of a 50yr ww'er.


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## Nubsnstubs (Aug 30, 2013)

Spike, it sounds like you started too close to the corner of the wood or bearing center center, and had no control of the cut. In that case, of course it's going to look like a catch, but it all has to do with a proper introduction of your wood to the router.The pins would stop that, even it's a curved piece. The fence would be an issue for curved routing.

Whenever I do any routing, especially raised panels or rectangular pieces, I always start about 1-2" above the lower end of one of the straight grain edges, cut across the end grain to the other side, then across the grain again, and finish the other edge, getting clean cuts all around the work piece. On single edge routing, I always use a fence.

Gloves seem to be gaining in fashion for woodworkers, but not this old fart. Just the other day while turning something, I got a piece of paper towel to wipe off some oil I noticed on my chuck. In less than a blink, it wrapped itself around the piece of spinning wood. When wiping off anything spinning, I always hold the wipee loosely just for the above stated example. No injury, but if gloves were part of the equation, it's a good possibility something unpleasant could have happened. ................ Jerry (in Tucson)


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## drobertson (Nov 13, 2009)

I think you are getting some good advice on the routing issues and I hope things are going well with your project.

My 2 cents is going to be directed at the gloves discussion that has developed. I had always been taught that gloves are never to be used around any machinery and I keep that as a strict rule around my shop.

Yes, I can see how they could protect your hands from flying chips, but I think there are better ways of doing that and the extra risks you create more than negate that benefit.

The main risk when you are wearing gloves around any moving tool is that they can easily catch in the moving blade/bit/tool/whatever. When this happens the flexible material doesn't cut, it grabs on. The next part is very messy. As the glove wraps around the moving part of the power tool it pulls your hand directly into the nasty part of the machine. This quickly turns into a meat grinding session with your hand.

This is the same reason we don't allow hanging loose clothing or, in the case of my wife and daughter, unbound long hair in the shop. Well advanced balding has solved that issue for me. 

Also, I personally think it creates a sense of over confidence with the tools you are working with. You stop thinking of your hand being delicate flesh and start assuming it is protected.

One experience I saw in a machine shop I used to frequent was a younger, impatient (and invincible) machinist reach down with a leather gloved hand to slow down a metal lathe as he shut it off. I guess he thought the glove was armor or something. It caught in the rapidly spinning machine and luckily tore the glove straight off his hand. One of his fingers was badly mangled in the process, but it was an injury he recovered from. The glove was nearly shredded, but most importantly it was still wrapped around the head of the lathe when it finally stopped. If the glove hadn't come off that could have been his arm. This was a large machine designed for machining titanium. It would have barely noticed a little flesh and bone trying to slow it down.

I am not trying to say every machine in the shop has that same risk, but hopefully you get the idea why gloves are so dangerous.

Now, I am also of the libertarian bent and if you still feel like wearing gloves after this then feel free to do so. Just don't expect to be allowed to do it in my shop.


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## KevinL (Sep 14, 2014)

> I think you are getting some good advice on the routing issues and I hope things are going well with your project.
> 
> Yes, I can see how they could protect your hands from flying chips, but I think there are better ways of doing that and the extra risks you create more than negate that benefit.
> 
> ...


Yes I agree with the above totally. 25 years as a Toolmaker and just finishing up my 9th year as an Instructor teaching tool & die and no gloves for running any machinery in either my shop wood shop at home or any of the machine tools at the college. For that matter, I wear no rings or a watch. I remember to put my wedding ring on when my wife and I go out on a date, she understands why I don't wear it everyday.

Several on the accidents that I have had to help with get folks out of, and or patch up to take them to the hospital have included people wearing gloves. Fingers are very much like a chicken leg bone when you are trying to find all the parts to get to the doctor. Many times I have heard, I thought that they would help, now look at me.

My students don't have the chance to wear gloves and that's my 2 cents.


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## FarmerintheWoods (Mar 3, 2017)

I had pretty much the same problem and I have a solution that works for me: a curved router fence.

I am working with curved pieces like the smaller of the two iin the pic below.

But first, the original design of the piece. I have a bench sander and the radius at the end of the belt is 1.65". So, I incorporated that dimension into the design of the piece. The smallest inner radius in the design is 1.65".

So, the outer radius of the curved side of the fence is 1.65". The slot is 1/2", because that's the diameter of the pilot bearing on the router bit, which is a 1/2" radius roundover bit.

You're looking at the underside of the curved fence, so you can see that the roundover bit can move freely through the entire length of the slot.

I have a frame and clamps that I use to re-position and hold the router fence as I make multiple passes with the workpiece, shaving off only maybe 1/8" at a time until the roundover is complete and the workpiece is directly against the pilot bearing. The slot opposite the curved fence is for routing the straight edge of the workpiece, but again, it's moved incrementally after each pass until the roundover is complete.










I searched the web in vain for a solution like this. If it's unique, all I ask is that it be called 'the Farmer fence' for future reference. And of course, say that it was first revealed here at Lumberjocks.


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