Unsafe Cross-Cutting: Avoiding Dangerous Table Saw Kickback
George VondriskaDescription
Table saw safety is a huge part of woodworking, and avoiding table saw kick back is a large part of table saw safety. You may find it tempting to try and use the rip fence on a table saw for cutting multiple pieces to the same size. There are scenarios in which this works, and scenarios in which it doesn’t. You need to understand the dynamic of length versus width, and how this affects the safety of the cut. This video explains how to safely make these cuts, and what to avoid.
The danger in crosscutting
What’s the problem if you use the table saw incorrectly for crosscutting? Two issues; table saw kick back, and possible contact between the saw blade and your hand. If a table saw is used incorrectly it’s relatively easy for the material to climb up onto the back of the saw blade. If this happens, things can go very badly very quickly.
Mastering the table saw
Few woodworkers will argue with the idea that the table saw is the heart of a woodshop, and key to many woodworking projects. As a result, knowing how to use a table saw correctly is a very important part of woodworking. There are so many table saw techniques available to you. A table saw is capable of much more than simple cross cutting and ripping. Be sure to check out the comprehensive collection of videos and articles that WoodWorkers Guild of America offers on table saws.
This is a very important aspect to using the table saw that I really want to make sure that you understand. Here's the deal. You've a a piece with these kind of proportions, maybe a shelf for a cabinet, and what you know is you need to make a bunch of them or your thinking is, I want to take advantage of the fence on the table saw to cut a bunch of these to identical size. So, you position the fence, and get ready to make this cut. Don't do it.
Here's the problem. I'm going to give you the formula here. The distance from the blade to the fence can't exceed the dimension that's against the fence. Here's what that means, you've got a rectangle going here. This side of the rectangle is way bigger than this side of the rectangle.
What's the problem? The problem is that if we start to make this cut the table saw blade has so much forward torque, so much leverage over here compared to the small of wood that's against the fence, it's very easy for this to start to turn. Let's throw the guard up and see why that's a bad thing, If this board starts to spin, the saw's unplugged, it climbs up on to the back of the blade. Now we're not cutting in this direction anymore, now we're lifting the material off the table. And in the blink of an eye what happens is that the board climbs up, the blade grabs it, the board continues to spin, and you get kickback.
Kind of the least bad thing is a kickback, the more bad thing is that the board comes around, if your trying to hold on to it, it can pull your fingers across the top of the saw blade. There are a lot of ways to get this board cut to the right length and do it repeatedly. This is not one of them. So again what you want do is make sure that the dimension between the blade and the fence does not exceed the dimension that is against the fence. So let's slide the fence over.
This cut we could safely do. Because this is less than this. Make sure you keep that concept in your head. It's going to help make you a safer user of the table saw.
Thank you George, great advice! I have "yet" to have kickback, but never heard of this tip. Is this when you use the miter instead?
I’ve been sucker punched twice by kick- back. I don’t want it again. Thanks for this and any other advice.
<strong> Ticket 17972 Thank you George - an easy formula to remember. In advertainly I have experienced some movement away from the fence as you have described and my uneducated approach has been to support the material with another piece behind the piece that needed to be cut. Is this method still dangerous ?
Hi George, I'm new to operating a table saw, so here's the question what if you are trying to cut a long pice of wood like a 2X4 that's 8' long, to a measurement of for example 12". With the 2" width being against the fence the 12" cross cut exceeds the amount against the fence. This is where we would use a miter gauge instead of the fence to make this cut safely correct? Thanks Alec.
Makes sense, Thanks George.
So, does that mean cutting a square is safe, or is it too close to being wrong?
Great tip George. You made it very easy to understand.
Never thought of it in that perspective, but makes much more sense to think of it that way. Thanks for the advice here.
I have been using the same table for thirty-five years without a problem. About three months I was cutting a piece of 3/4 plywood almost the exact size as what was used in this demonstration when I experienced my first kickback. Fortunately I was standing to the right of the blade pushing with both hands. The cut off piece of plywood about one square foot kicked back and hit my left arm above my wrist. I thought my arm was broken and went to the emergency room at the near by hospital. Turned out my arm was not broken, however I had a cut about two inches long. Within two days my left arm was black and blue from my wrist to above my elbow.
You forgot to mention that you need to stay away from the wood while cutting. Stay off to the side while cutting. This way, if it happens, you won't get hit by the wood.