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1 October 2020

Chainsaw jargon buster

From air filters to top handles, our jargon buster explains all the terms you're likely to come across when buying a chainsaw.
Chainsaw in front of cut logs in firewood stack
Adele Dyer

Chainsaws have a range of handy features to help you manage the garden, but before you shop for a chainsaw, make sure you're familiar with the key terms.

Our chainsaw jargon buster guide runs through the must-have chainsaw features that will help you pick the perfect model for you.

Just want to see which chainsaws we recommend? Catch our expert verdicts with our full range of chainsaw reviews.

Air filter

Air filters are part of a petrol chainsaw's engine. Due to the high levels of dust involved in sawing through wood, you should check the air filter each time you use the machine, and clean and replace it as necessary. It's important to be able to access the air filter easily.

Anti-vibration system

Most chainsaws have a system of dampers and springs between the body of the chainsaw and the handles to reduce vibration. This helps to prevent vibration-related problems in your hands and arms, such as 'white finger'.

Automatic chain oiling

Chainsaws need chain and bar oil to keep them running smoothing and to stop the chain from overheating. Oil stops these metal parts from rusting and protects the chain teeth. Most chainsaws have a small pump that pushes oil onto the chain and bar through a small hole in the bar itself. It's essential to keep the oil lines and lubrication holes clear of sawdust. 

Automatic choke

If you find starting a petrol chainsaw tricky or have a tendency to flood the engine, then look for model with an automatic choke. 

Boring cut 

This is a cut using the tip of the chainsaw to bore a hole through the wood. It's an essential cut if you're felling trees, but should not be attempted without training. This cut is dangerous as it brings the tip of the chainsaw into contact with the wood and so it's more likely to kick back. Some chainsaws have tip-guards to prevent kickback but it also means you can't make a boring cut.

Bumper spikes 

Sometimes called 'dogs', bumper spikes are a set of vertical spikes at the base of the chain bar. They hold the saw steady against wood as you cut. Look for a machine with metal spikes rather than plastic ones, as metal grips better.


The chainsaw chain should match to the guide bar and saw. The chain is made up of a cutting link, with cutting edge and a depth gauge and bumper links, also called guard links; drive links that slot into the groove in the guide bar; and tie straps that tie the chain together. For safety, as well as effective cutting, the cutting links on the chain should be kept sharp. The depth gauge, which controls how deeply the chainsaw bites into the wood, should be filed to match the height of the cutters.

If you're unsure how to keep your chain sharp, you should have appropriate training or take your chainsaw to a dealership where it can be maintained correctly.

Chain brake

The chain brake acts as a hand-guard on the top of the chainsaw but, more importantly, if the tip of the chainsaw gets embedded in the wood as you cut, making the chainsaw 'kick back' or flip powerfully up towards your head and shoulders, the chain brake will engage and stop the chain almost instantly.

Chain catcher

The chain catcher is a little hook of metal that catches the chain if it breaks or comes off the bar. It should reduce the risk of the loose saw chain hitting you in the leg.

Chain tensioning

If your machine has a tool-free chain-tensioning device, it will have a wheel to move the guide bar to maintain proper tension on the saw chain. Otherwise, you will have to use a multi-tool to tension the chain using the bar nuts. It's essential to keep the chain at the correct tension when you're using a chainsaw. As the chainsaw heats up in use, the chain can become loose and there is an increased chance of it coming free from the guide bar. 

Chainsaw boots

These boots have steel toecaps and protective fabric designed to reduce damage from a running chainsaw chain. 

Chainsaw gloves

These protective gloves have extra padding on the left hand to protect this hand that operates the chain brake and so is closer to the moving chain.

Chainsaw trousers

Chainsaw trousers have special pads of material which will foul the chain if it comes in contact with them. The material stops the chain and reduces the risk of a life-threatening injury if the chainsaw comes in contact with your legs. You can get full trousers, or chaps that cover the front of the legs only.

Guide bar

This is the metal bar that the chain runs around. The longer the bar, the thicker the log you can cut through. 


Kickback happens when the tip of the chainsaw comes into contact with a relatively immovable object, such as a large log, or gets stuck in a cut as the wood moves. If the chain jams in the wood, the bar will hurtle upwards towards your face and shoulders, potentially causing fatal injuries. It is important to get trained in the safe use of chainsaws to prevent injury through kickback and handling errors.


Multi-tools are a screwdriver and socket tool that is designed to allow basic chainsaw maintenance to be carried out. If your chainsaw doesn't have tool-free tensioning, a multi-tool to tension the chain is essential. 


PPE stands for personal protective equipment. If you are using a chainsaw, you should wear safety clothing. This includes a helmet, eye protection, ear defenders, chainsaw gloves, chainsaw trousers and chainsaw boots. Any clothing that has chainsaw-protective fabric, such as boots, trousers and gloves, will have a chainsaw logo on it and give a rating to show the maximum chain speed that the protection is suitable for.


A plastic sheath that covers the blade of the chainsaw and protects it from dirt and damage when it's in storage or being transported. A chainsaw blade will be sharp enough to cause injury even when it's not being used, so the scabbard is essential protection when you're carrying it.

Tip guard

A tip guard is a section of metal that covers the end of the chainsaw blade. It reduces the risk of kickback for inexperienced users but prevents the chainsaw being used for technical cuts such as boring cuts. 

Top handle

Most chainsaws have a rear handle and are designed to be used two-handed. Top-handled chainsaws can be used single-handed, but have fewer safety features. They are best used by professionals who need to work at height.

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