Watch: Farmer know-how - sharpening the chainsaw

There is a range of tools available for sharpening the chain of a chainsaw. There are flat file guides, which allow for the control of the angle and the depth the file is sharpened at and they can be adjusted to suit different chain sizes, while others are designed only to suit a certain chain size. Having a simple spanner is handy for measuring the length of each cutter to ensure that they are the same size. An Oregon depth gauge tool helps when filing the rakers. Files also come in different sizes and, again, the size used depends on the size of the chain. A vice is essential for holding the chainsaw steady when sharpening the chain to do the job evenly and safely. If you do not have a vice, a simple stump vice is handy and it can be driven into the stump of a tree or the table.

The chainsaw is tightly placed in the vice. You should wear thick chainsaw-suitable gloves to protect your hands from the chain. Establish if the chain needs sharpening. Put the file guide that matches the chain size on the chain. One way to choose the correct file size is by sitting a file on the cutter. It should sit comfortably with 20% of the diameter of the file above the cutter. When the correct file is selected, it should be parallel with the witness mark at the back of the cutter. From there, take smooth strokes against the cutter. You will see that some iron filings will start to build up and they can be tapped off. The important thing is to make sure that the cutter is sharp, has a good working corner and that the gullet is clean.

Watch a detailed tutorial with Kevin in our video below:

Once all the cutters are sharpened, you can move on to the depth gauge (raker at the front of the cutting length). The idea is to lower the depth gauge as the cutter gets shorter. To regulate the height of the depth gauge, a file guide is used to improve the accuracy and avoid excessive sharpening back. “If you don’t get it right sometimes, the saw will not cut properly. You won’t get the efficiency and if you go too deep, then we risk the saw kicking back, which can cause bad injuries,” explained Kevin. To sharpen the depth gauge, place the file guide on top of the chain.

It is important to wear protective equipment for chainsaw use. Some protective clothing will tell you the chain speed at which it will protect you. A pair of technical extreme chainsaw trousers have clogging material designed to prevent serious leg injuries. “Some people complain about the cost of safety equipment but it is inexpensive compared with the cost of an accident,” explained Kevin. A chainsaw helmet is essential with certified earmuffs and certified visor to protect your hearing and face. A health and safety kit is essential, especially for wounds that need dressing. A mobile phone should be carried in case of an emergency.

When using a chainsaw you should try to keep out of line with the bar of the chain. Crosscutting can be done either right foot forward or left foot forward, but we tend to do right foot forward these days as the bar and chain are always out of line with the body. The problem with a normal stance is as you get lower, you start to expose parts of your body, especially the neck to kick back. If you want to lead with the left foot, you should always keep your head away from the chain in an effort to avoid kick back.

Does it need sharpening?

The golden rule to working a chainsaw is if you find yourself leaning on it to make it cut, you need to sharpen it. Visual inspection will tell you a lot about the condition of the chain.

First of all, check the point on the cutter, as it needs to be sharp. If not, it will get dusty. Next, look at the edge along the top plate.

There should be a fine edge of chrome on top of all the cutters. If there is any staining or blackening, it could mean that the chrome is damaged and you need to sharpen past that. If there are variations in cutter length, it will lead to a lot of vibrations and irregular cutting.

If all the cutters are shorter on one side, you tend to get a pull on the chain in one direction; therefore, you have to try and keep them even. Once you have decided what needs to be done, you should look for the shortest cutter. When it is found, it is marked. You should start on the most damaged one first because it is usually down the most. Using a spanner, you can measure the width of each cutter to ensure they are all the same size.

Keep the manuals

Copies of all the instructions and manuals for both the chainsaw, the chain and files should be kept. The instructions have information on filing angles, depth gauge settings, how to position the file on the chainsaw guide and hardwood and softwood gauge settings.

The box that your chain comes in is really useful. It gives information specific to the chain that you bought, the file size you should use and the angle they should be sharpened at.

Mark which product it is when you buy the chain, so you will always have that information.

Personal protective equipment

When operating a chainsaw, you need to gear up before picking up the saw. It is your first line of defence. The most important safety gear to wear are: