⚠️Chainsaw Kickback: Understanding and Preventing a Deadly Reaction
A chainsaw kickback is one of the most dangerous events that can occur while operating a saw. At best, it will give you a good scare. At worst, you could end up with a life-altering injury.
If you don't believe us, a quick Google search for "kickback injuries to the face" will show you exactly what's at stake.
This is why any person with an iota of sense about personal safety will use proper safety gear like gloves, chaps, and, at a bare minimum, a pair of safety glasses.
Personally, we would never use a chainsaw that didn't have a working chain brake, which is designed to stop the chain instantly during a kickback. In many places, like New Zealand, it's actually against the law to sell a chainsaw that doesn't feature a chain brake.
Let's dive into the science of what causes kickback and how you can prevent it.
The Science of Kickback: A Violent Transfer of Energy
A chainsaw's engine produces immense rotational energy, which is transferred to the chain. When you are cutting properly with the bottom of the bar, this force pulls the saw away from you and into the wood. However, if the upper quadrant of the guide bar's nose, known as the "kickback zone," makes contact with a solid object, the chain can suddenly stop or get pinched.
The rotational energy has nowhere to go, so it is transferred back into the body of the saw. This causes the guide bar to pivot violently upwards and back towards the operator, often with the throttle still engaged.
There are two primary types of kickback:
- Rotational Kickback: This is the most common and dangerous type. It occurs when the moving chain in the kickback zone at the tip of the bar strikes an object.
- Pinch Kickback: This happens when the wood closes in and pinches the saw chain in the cut. The chain is stopped suddenly, and the saw is pushed straight back towards the operator.
✅How to Avoid Kickback: Technique and Maintenance
Preventing kickback is a combination of proper technique, situational awareness, and rigorous saw maintenance. The experts at Oregon have identified several key causes that can lead to kickback, either alone or in combination.
Causes of Chainsaw Kickback vs. Prevention Strategies
| Cause of Kickback | Prevention Strategy |
|---|---|
| Contact with the tip (Kickback Zone) | Proper Handling: Always hold the chainsaw firmly with both hands and maintain constant awareness and control over the bar tip. |
| Pinching the saw chain | Correct Cutting Technique: Ensure cuts are stable and controlled. Avoid cutting with the tip unless you are trained and prepared for the risk. |
| Improper chain tension | Regular Maintenance: Check and adjust the chain tension before every use as per the manufacturer’s guidelines. |
| Dull or improperly sharpened chain | Routine Sharpening: Sharpen the chain regularly to ensure it cuts smoothly and efficiently, which reduces the need to force the saw. |
| Incorrect depth gauge settings | Proper Maintenance: Ensure depth gauges are set correctly using a depth gauge tool. Too low, and the chain bites too aggressively. |
A Step-by-Step Guide to Preventing Kickback
Using proper operating techniques is the number one way to reduce the likelihood of kickback. Here's what to do:
- Hold the chainsaw firmly with both hands. Wrap your left thumb firmly under the front handle.
- Be aware of the location of the guide bar nose at all times. Do not let it come into contact with any object unintentionally.
- Be especially careful when cutting small limbs or light material that may catch in the chain.
- Do not over-reach or cut above shoulder height.
- Use extreme caution when re-entering a previous cut.
- Ensure all safety devices, especially the chain brake, are working correctly.
This excellent video tutorial provides some great tips on avoiding kickback. It starts with a hokey demonstration, but the advice given by the presenter is top-quality stuff:
By following good chainsawing practices and being constantly aware of where you place the tip of your chainsaw, you can dramatically reduce the chance of a kickback occurring.
The other half of the equation is ensuring you always wear adequate safety gear to protect yourself from serious injury when the unexpected happens.