How to sharpen a chainsaw the right way

Even the best saw chains become blunt over time. Once this happens, work becomes more strenuous and the chainsaw is exposed to increased wear. In addition, it puts more physical strain on you, and the cutting result becomes less and less satisfactory. 

If you notice the following signs when working with your saw, you need to sharpen your saw chain or maybe even replace it.

1. The saw chain does not pull itself into the wood. It needs to be forced to cut by applying pressure on the powerhead.
2. The saw chain produces fine sawdust instead of coarse chips when cutting or cutting to length, i.e. when cutting vertically through the wood.
3. Smoke is produced in the cut despite chain lubrication and correct chain tensioning.
4. The chainsaw pulls in one direction and the cut becomes crooked. This is particularly indicative of blunt or  unevenly long teeth on one side.
5. The chainsaw chatters and bounces when sawing. Precise positioning is difficult.

The depth gauge setting is the distance between the leading edge of the top of the saw tooth and the top edge of the depth gauge. The greater this distance is, the more wood is planed per tooth.

The depth gauge setting decreases when the saw teeth are sharpened. This is because the saw tooth becomes shorter and also flatter due to its shape (thinner and flatter towards the rear) during sharpening.

In order to achieve a good cutting result, the depth gauge setting must therefore be checked and adjusted if necessary every time you sharpen your chainsaw.

Correctly maintaining all angles and dimensions “freehand” is very difficult and requires a lot of practice. STIHL therefore recommends that you use filing aids.

You can sharpen the cutting teeth of your chipper tooth saw chain yourself using a round file. However, the tool you use has to match the saw chain.If you use the wrong file you can actually reduce the cutting performance of the chain. 

The right round saw chain file to choose depends on the chain pitch of your saw chain. Each chain pitch is assigned a specific round file diameter.

Choosing the right round file for sharpening your chainsaw

The chain pitch assigns a chain to certain chainsaw performance classes. You can easily find out the chain pitch for all STIHL saw chains by checking the identification number on the depth gauge. You can then simply check the required file diameter in the STIHL conversion table.

If the number on the depth gauge is no longer legible, the chain pitch can be determined by means of a chain reference guide. Alternatively, you can calculate the chain pitch. For example, you would measure the distance from the centre of one riveted bolt to the centre of the next one using a calliper, and divide the result by two to obtain the chain pitch in millimetres. However, since the chain pitch is always in inches, you will still need to convert the result accordingly: one millimetre equals 0.039 inches, which means that you must multiply the measurement in millimetres by 0.039 to obtain the corresponding value in inches. Once you have calculated the value, simply search for the corresponding saw chain file diameter in the STIHL conversion table:

Worth noting:  Please note that saw chain files have a different file cut – in other words a different surface structure – from workshop files, for example. The latter are therefore generally unsuitable for sharpening saw chains.

The depth gauge is part of the blade tooth of the saw chain. It determines how deep the incisor penetrates into the wood when sawing with your chainsaw and how much wood it planes off in the process. For optimum cutting performance, the depth gauge setting must therefore be correct for the type of wood you are working with. We will explain what you should look out for.

The depth gauge and wood type should be coordinated

Each type of wood behaves differently during sawing. With the right depth gauge setting, you can make the work easier for yourself and your saw. We recommend that you consider the type of wood you usually saw when purchasing the chain. 

Hard woods are more resistant to sawing than soft woods. Therefore, the depth gauge setting should not be too high when sawing hard wood. When cutting softwood outside the frost season, the setting can be up to 0.2 mm larger. The filing gauge of the next larger chain pitch can be used to do this. STIHL also offers a special filing gauge 

that can be used to directly determine the optimum depth gauge distance for hard and soft wood.

The chain pitch provides orientation when selecting the depth gauge distance. The table above shows how large the depth gauge setting should be for hard wood.

» VIDEO GUIDE: SHARPENING THE SAW CHAIN AND DEPTH GUAGE WITH THE STIHL 2-IN-1 FILE HOLDER 

Our video guide will show you how to sharpen the saw chain and depth gauge of your STIHL chainsaw in a single operation using the 2-in-1 file holder. 

• Start by marking a blade tooth with a felt tip pen. The marking will help you check that the material is being removed evenly. After two to three filing strokes, check how much material has been removed. If the material has been removed evenly, you’re filing correctly. If the felt tip marking has only been removed in some places, check that you are using the correct file and make sure that you are not holding the file too high or too low.
• Do not keep working with your saw chain until it is completely blunt –  it just takes a few strokes of a file to keep your saw chain sharp.
• Count the file strokes and apply the same number to each blade tooth; this process will wear all the teeth to an equal length.
• If you find that the blade teeth in one row are shorter than those in other rows, you have applied greater filing pressure to one side. Even out the length of the teeth by performing one to two additional file strokes on the longer teeth.
• Product tip: you can use the STIHL 2-in-1 file holder to sharpen the teeth of your saw chain and reset the depth gauge to the correct height at the same time.