Miter-Saw Kickback Injury Story
Miter-saw one, woodworker zero. Pain. Injury. January 19, 2011
This is what happens when a miter saw kicks back, upward, and catches your hand on the way up. Ouch! And yes, that is my blood all over the floor while I was calling 911 yesterday.
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(Business and Management Forum)
From contributor G:
Best wishes for a speedy recovery. It's easy to underestimate a chop saw. Everyone seems to think it won't happen to them. I had a coworker with 20+ years as an excellent installer who cut off his hand at the wrist while mitering some large crown moulding onsite. Luckily they reattached it. It took years before he could finally pull the clutch on his motorcycle.
From contributor M:
Thanks for posting. Tell us exactly what you were doing that caused the saw to kick back and up. Hopefully from your accident we can all learn. Wish you a speedy recovery.
From contributor S:
Were you holding the trigger with your right hand? If so, shouldn't you hold tighter? If you were cutting with your left hand on the trigger, why was your right hand so close to the blade? Are all the guards in place?
It truly is unfortunate about your hand, but most mishaps aren't accidents. When I see employees being unsafe, things stop immediately, lectures follow, and if more unsafe things happen, employees get unpaid time off. 100% safety at all times is my shop policy.
From contributor F:
Miter saws are very dangerous - never underestimate how much energy they can generate when things go wrong. I have taken to using a push stick to hold down the work - I don't even want a close call. Hope you heal, and thanks for posting your experience - I hope we all learn from it.
From contributor C:
Thanks for the post - it reminds me to practice safety. I ran my thumb through a back cutter once. Luckily it was saved and I was back to work quick.
From contributor I:
I am sorry about your injury. I hope your business is not too much affected. I know that accidents can happen to even the most safety conscious carpenters. Can you tell us in detail how it happened? Was the force of the kickback enough to kick the handle out of your hand, and then the blade cut you on the way up? Was the guard slow to retract for some reason? I seem to remember that my Dewalt 12" used to do that. What could have prevented it?
From contributor H:
I would also like to wish you a speedy recovery! I was injured on the job once (whilst working as a chef). The ladder (that was supposed to be attached to the wall!) fell out from under me. I fell about ten feet and hit my head! I got a bad concussion and a couple weeks off from work, then I had to run around to catch the bean counters and straighten the whole mess out with insurance emergency bills and whatnots. It's better to stay healthy!
When I started working in the trade, I made my share of mistakes too. Hereís my classic! Yes, the perils of a pneumatic stapler without a safety... Ouch. Thanks for the reminder of the perils of the shop!
From the original questioner:
I am trying to get back to work today. This is a Dewalt 708 sliding compound saw, and I was cutting some 4x4 cedar posts to 3 feet long that we had lying around as a favor... Love it!
It is unclear exactly what happened because it was incredibly fast and violent, but this is how it went. I was trimming these 4x4s with a nice sharp blade with no problems. I have been in the cabinet industry for 28 years and am well seasoned and know my way around things.
The Dewalt 708 has a horizontal handle and a belt drive. Apparently while cutting a 4x4, the saw bound and the belt tensioned inside the belt cover and shot the saw upwards at the speed of light, breaking my thumb and pointer finger on the way up. Then the blade cut the palm of my hand wide open like a taco. The cut was held back because my bone stopped it. It's about 4 inches long and took out some nerves, which were reattached. The guard is in place but didn't close fast enough to protect my hand.
If you look at the blade, it appears it was going backwards as it cut into me, which is weird. I guess the belt tension was extreme to do this. If you turn the blade on the saw, the belt feels strange and I haven't looked behind the cover yet because I am still trying to recover physiologically from the sheer brutality of the incident, and support would be great. Thanks everyone.
From contributor U:
I had the exact same issue years ago using a Makita sliding miter saw. Because the grip/handle is different, it caught me in the back of the thumb as the head came flying up out of the cut. In my case, there was either a lot of tension in the 6" wide part that I was cutting, or there was a slight crown facing forward that let the front of the cut close up and pinch the blade. I got lucky and didn't cut anything but skin, but the depth was about 1/4" running sideways so that there was just a flap of skin with 1/8 kerf missing underneath.
Lesson? Crown towards the fence, and learn to recognize boards that are likely holding tension (fuzzy grain on ripped edge, extreme crown, etc.).
From contributor A:
Thanks for sharing so we can all learn something from this. I am just sorry it had to be at your expense. Our shop wishes you a speedy and full recovery!
From the original questioner:
Thanks for the concern. It's not so much the injury that's bothering me but the cause of the injury, and what to do in the future to prevent something like this. I don't know what I could do differently. The whole ordeal was so violent and unclear I can't get a handle on it. It's something I will have to try to understand and overcome every time I walk up to a miter saw in the future.
From contributor Y:
I have run my compound miter saw for years and have found that taking too deep a cut all at once causes trouble. I watched my personal friend Tommy Silva on TOH and he eases into cross cuts when using a CMS. Take multiple passes, making sure both ends of the stock are supported while cutting. Even with all that, I think it is important to think about hand positioning in case something goes wrong. The original poster is correct - they kick back much faster than a human can react.
Hope you heal up, and that includes the PTSD. Speaking of which, a very heavy piece of white oak fell off my band saw the other day and hit me in the leg. I went into shock, but as soon as I could, I went back out and finished cutting that block. Getting back on the horse can be good therapy.
From Gary Katz, Architectural Woodworking Forum technical advisor:
My sympathy and understanding! There are so many things that can go wrong at power tools, especially miters saws, table saws, and circular saws. And many of those things are incredibly difficult to protect against, if at all.
It sounds to me like the blade bound in the wood, the wood slammed into the motor, and kicked the handle right out of your hand. There are so many things that can cause the blade to bind in the wood - a warp/twist/cup, or even a small chip of wood against the fence.
Were you using a continuous fence to support the 4x4 material? Or were you having to hold the material down with one hand?
Either way, I'm relieved that you didn't lose fingers or your hand. I'm sure the healing process will take a lot of time (emotional healing, too!). Be patient! Remember how long it took to learn many of the techniques you probably take for granted today. It takes a long time to learn healing, too.
From contributor E:
I almost never try to cut thick wood in one pass on a mitresaw, because it tends to bind up when the pressure is relieved. When cutting 4x4s, I cut part way through the material, and then rotate it to cut through. Leave a little bit of length to clean up the end, and the saw cannot bind if the blade is not buried in the material. Even wide boards will sometimes bind when roughing out stock - I sometimes cut halfway through and flip the board just to relieve the pressure. These precautions will not prevent binding in all cases, but there will not be as much kickback pressure from the saw.
Sometimes it looks like you are taking twice as much time to cut boards by flipping and double cutting them, but if you figure the lost time due to injuries, you are saving time. If someone criticizes you for doing this, they are demonstrating their ignorance of basic safety practices - don't ever let anyone talk you into doing something dangerous in order to save time.
I have found that the highest incidences of kickback are found when rough-cutting stock that doesn't have a straight edge; any way you place it against the fence allows it to shift when the saw cuts through it, but the crown against the fence is safer. The 4x4s that you were cutting probably had a little crown to them, and that may have contributed to your accident.
Almost everyone who works with their hands has had an injury of some kind in their career, and it can make you a better and safer craftsman in the future. I wish you a speedy recovery.
From contributor I:
I think we always consider the miter saw a safe tool, but a 12" blade has a lot of inertia. I noticed on my Dewalt after I finish cut that if I just let go of the handle and allow the head to rise on its own, the guard is slow to retract. The electric brake would actually slow the spring's ability to raise the head, so it would come back up nice and slow. I noticed the delayed guard retracting, and I guess in the back of my mind I knew there was a danger there, but I would never have thought what you described could happen. Now hearing that another injury was caused in the same way on a different brand saw makes me think we should contact Dewalt/ Makita. They might not know this can happen.
I do not have a miter saw in the shop now. We use a jump saw and the slider for everything. I think these are safer because the guards are more... complete, I guess. But I miss my Dewalt. They are just too expensive here. For the price of a 12" slider, I can buy an industrial jump saw or RAS.
From the original questioner:
It appears the saw may have locked up for a split second and the momentum stretched the drive belt and rocketed the blade backwards, which kicked the saw upwards and broke a finger and badly bruised all 5 fingers. Then when the saw reached its travel upwards, the momentum rotated the guard 180 degrees, exposing the blade, which caught the palm of my hand, severing the carpal tunnel and the median nerve. The cut was to the bone and required 30+ stitches. I lost a section of the median nerve (2") which was replaced by a bio-tube. I will have to wait several months for the nerves to grow together to regain feeling in my hand.
The saw kicked after I was through the cut, so I cannot tell you what happened, as this appears to have been a mechanical flaw, not operator error. Thanks for the concern, and anyone owning a dw708 may want to reconsider using it.
The comments below were added after this Forum discussion was archived as a Knowledge Base article (add your comment).
Comment from contributor A:
Sorry to hear about your accident. I too had the same thing happen and the damage was severe. As the saw kicked up and my hand went up with it I somehow also hit the blade guard as it was covering the saw and it shattered into bits as my hand now touched the blade, partial amputation to the ring finger and middle finger and across the palm. I too have the full hand bandage as they stitched everything back together and itís only been two weeks.
I have emotional scars. When this happened it was so violent I did not think I would have time to wait on an ambulance. I grabbed a shirt, covered the spewing blood, and drove myself to the hospital driving a stick shift. After all said and done I have a problem looking at the saw. Blood still stains the floor and I am in the first stages of recovery. Some things are still foggy about that night but it scares me to see that the blade guard that was supposed to protect me in some way just shattered into bits as the accident occurred. Hope a speedy recovery to you as well, and I do understand your after affect and horror.