If you have ever experienced a power tool or the piece you are cutting get completely out of your control than you likely will never forget. While power tools are huge timesavers and make the job quicker and easier, they don’t come without risks. Kick back is a phenomenon of power tools with rotating blades, including the chop saw or miter saw. So why do chop saws, in particular, kick back?
Blade kick back occurs when a larger material is cut but pinches the blade, causing the spinning blade to be violently kicked back towards the saw operator. Material kick back occurs if a small cut piece slips into the base plate groove, jams against the blade, and gets launched as a projectile.
Depending on the size of miter saw you have it may rotate at speeds under 3,000rpm(for the larger blades) up to 7,000rpm(for the smaller ones). Kick back on a chop saw is significantly different from that of a table saw and can lead to severe injuries. But why does this kickback happen, and is there anything you can do to avoid it or stay safe if it does occur?
What Is Chop Saw Kick Back?
There are two types of kick back that can occur with a chop saw or a miter saw, and both events can not only be startling but also extremely dangerous.
Material Kick Back
The first type of chop saw kick back occurs when the blade catches a loose piece of material and hurls it at lightning speed backward. While this is not towards the user of the saw, it can ricochet off of the back of the fence, a wall or at someone if they are standing in a place other than behind you when they are cutting.
This can happen if you do not wait for the saw to stop rotating before lifting it up, away from the material being cut. In this instance, the errant cut-off piece can be sent in the direction of the saw operator.
Another instance where material can be thrown back at the saw operator is when a small piece is being cut off the material, and the cut-off piece slips into the slot in the base plate of the miter saw. This can pinch the blade and cause the errant piece to be ejected at speed, or kickback the blade of the saw, which is the next type of kickback that we will explain.
When dealing with lighter or smaller material like when your cutting PVC pipe with your miter saw this can happen more often if you are not careful.
Blade Kick Back
The second type of chop saw kick back is much more dangerous since it involves the blade being kicked back towards the saw operator. This is a particular problem on chop saws that have a sliding arm where you pull the saw towards you and then down into the cut and push the saw towards the back fence.
With this type of blade kick back, there are varying degrees of severity. If the blade gets slightly pinched by the workpiece, you will feel a bit of a jerk in the saw, and the blade will move back slightly towards you.
This more gentle type of kick back is disconcerting, but it is generally controllable and should not give you any cause of concern other than to be a little more careful with how your position and secure the piece of material being cut.
The other type of blade kick back is much more violent and happens very fast. This is where the spinning blade gets severely pinched and locks up, flinging the motor and the blade back towards the operator and also in an upward motion.
The speed and violence of this event does not give the saw operator to react and pull away from the danger zone. The speed at which this happens also does not give the blade guard time to swing down to cover the spinning blade.
Does Kick Back Cause Injuries?
Kick back can certainly cause some serious injuries to the chop saw operator. Material that is thrown out by the spinning blade can cause a penetrating wound that can be deep. This type of injury could be devastating if the impact is to the eyes, which s one reason why eye protection should always be worn in the workshop and especially when working with power tools.
The material being kicked back by a miter saw, or a chop saw is the least likely of the two kickback types to cause major injury.
The saw blade kick back has resulted in a number of serious injuries to chop saw operators, including slicing hands and fingers open deeply enough to cause tissue and nerve damage, which can result in a permanent disability.
With a serious kick back incident on a sliding miter saw, the blade kicks back along the slide towards the operator and then also swings upward in an arcing motion.
This places not only hands and arms at risk of serious injury but also any body part such as your torso, neck, and face that may be in the way of the arcing blade.
There may be any number of reasons to be using your miter saw, but a common household project is building a fence. Be careful to use proper safety during every project, and if you need a couple hints for fencing your corner lot or why to choose screws over nails for your fence than check these articles out.
How To Prevent Chop Saw Kick Back
Chop saw kick back is caused by material binding on the saw blade or small off-cuts that are launched by the spinning blade.
Here are some helpful methods and tips that you can apply when using your chop saw to prevent kick back from occurring and thereby avoiding any associated injuries that could result.
Tips To Prevent Material Kick Back
When it comes to material kick back, there are a number of things you can do to help lessen the potential occurrence of this type of chop saw event, as well as safety measures to ensure you are not in the firing line should it occur despite your preventative measures.
- Make a zero-gap clearance plate. The miter saw comes with a base plate that has a gap that is wider than the saw blade. This is to enable the blade to cut at angles. This wide gap allows small off-cuts of material to slip in and potentially bind on the blade and get launched by the blade as a projectile. Create a new base plate for your chop saw that only has a slot that is the width of the saw blade. This will prevent small off-cuts from slipping into the gap. The base plate can easily be made for a piece of plywood.
- Stand to one side. Stand to one side when making the cut. This would usually be to the left of the blade, as you operate the saw with your right hand. Should any off-cuts kick back, you will not be in the direct line of fire for the piece of wood.
- Always wear personal protection equipment. Eye protection is crucial to preventing this type of event from damaging your eyesight.
Tips To Prevent Blade Kick Back
The blade will kick back when the piece of wood being cut off moves and comes into contact with the blade, and thus binding on the blade. Often once the cut, this will occur as the blade completes the cut and the loose piece of wood moves and binds on the blade.
Taking some precautions with the workpiece and paying some attention to the shape of the piece being cut can go a long way towards preventing blade kick back.
- The workpiece must contact the base plate. If the workpiece or piece of wood that you need to cut is bowed, you should place it on the base plate so that there is no gap between the base plate and the wood. This may mean turning the wood over so the ends of the bowed wood point up. This will make sure that the crown of the bowed piece contacts the surface of the base plate. This will stop the cut-off piece from dropping down after the cut and binding of the blade.
- The workpiece must contact the back fence. There must be no gap between the workpiece and the back fence since the pressure of the cut is forcing the wood towards the back fence. If there is a gap, the cut-off piece can angle forward after the cut and bind on the blade.
- Make sure there are no staples, screws or nails in the wood. Nails in the wood can not only blunt your blade but could also bind the blade and result in severe blade kick back.
Conclusion
Power tools are without a doubt a time saver in the workshop, but familiarity with these machines can sometimes lead to a blasé, cavalier attitude when using them.
Always treat these powerful machines with respect and never take shortcuts or make any cuts on them without the correct protective gear or taking the precautionary measures to work safely with these tools. The risks are simply not worth it.