Chainsaw Care: How to sharpen a saw chain

All cutting attachments need regular maintenance to perform at their best. Learn how to sharpen your STIHL chainsaw so you get the best possible cutting performance.

STIHL MS 261 C-M petrol chainsaw with Light 04 guide bar next to STIHL MotoMix fuel mixture before sharpening
STIHL saw chain files and chainsaw chain on a workbench in a workshop

TIME TO SHARPEN THE SAW CHAIN: HOW CAN I TELL IF MY CHAINSAW CHAIN IS BLUNT?

Even the best saw chains become blunt over time, and when they do your chainsaw becomes less effective and suffers increasing wear. If you notice any of the following while working with your chainsaw, you should sharpen or possibly even replace your saw chain.

Five signs that it’s time to sharpen your saw chain

1.  When you use your chainsaw the cutting attachment doesn’t pull itself into the wood; instead you have to force it to cut by pushing down on the handles.

2. When cross cutting, the saw chain produces fine sawdust rather than coarse chips.

3. When you make a cut it produces smoke, even when the chain is lubricated correctly and chain tension is correct.

4. The chainsaw does not cut straight and the cut pulls over to one side. This can indicate that you need to sharpen your the blade teeth on one side, or that the length is uneven.

5. The chainsaw chatters and bounces when sawing making it difficult to use with precision.

A man wearing STIHL gloves filing the chain of a STIHL 261 C-M petrol chainsaw with a round saw chain file

Video guide: Sharpening the saw chain and depth gauge with the STIHL 2-in-1 EasyFile

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

What is the depth gauge setting?

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.

The 2-in-1 EasyFile maintains the depth gauge automatically by filing both the tooth and depth gauge at the same time! 

A person with STIHL file holder guide on a STIHL Light 04 guide bar

Filing TOOLS for sharpening a chainsaw

Getting all the angles and dimensions right while working freehand requires patience, experience and practice. STIHL recommends you use filing aids when you sharpen your saw chain to make the process simpler. 

A person with STIHL file holder guide on a STIHL Light 04 guide bar

Sharpen your chain with a round saw chain file

You can sharpen the cutting teeth of your chipper tooth saw chain yourself using a round file. However, the tool you use must match the saw chain. If you use the wrong file you can actually reduce the cutting performance of the chain. We will explain how to select the right round file.

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.

Digit indicating the chain pitch on the depth gauge of a chain

If the number on the depth gauge is no longer legible, the chain pitch can be determined by means of a chain reference gauge.  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:

Marking on the depth gaugeAlternative marking on the depth gaugeChain pitchRound file diameter
11/41/4"4.0 millimetres
2325.325"4.8 millimetres
33/83/8"5.2 millimetres
4404.404"5.5 millimetres
6P, PM3/8” Picco4.0 millimetres
7 1/4” Picco3.2 millimetres

Good to know

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.

How to sharpen a chainsaw with a file kit

Product tip: you can use the the 2-in-1 EasyFile to sharpen the teeth of your saw chain and reset the depth gauge to the correct height at the same time.

Sharpening the chainsaw STIHL HEXA

Sharpening a chainsaw has never been so easy: The innovative STIHL 3/8" Rapid Hexa saw chain can be sharpened using the specially developed hexagonal Hexa saw chain file – without any additional sharpening aids. The new hexagonal file is perfectly adapted to the innovative shape of the Hexa blade tooth, and allows for fast and virtually perfect sharpening of the saw chain at the ideal sharpening angle. Watch our video to see exactly how it works. Thanks to its innovative tooth shape, the Rapid Hexa saw chain is also highly durable and offers a 10 percent improvement in cutting performance compared to the 36 RS.

Video: The 3/8" Rapid HEXA saw chain from STIHL

A man sharpens the STIHL Rapid HEXA chainsaw using a hexagonal file

To sharpen your chainsaw Rapid Hexa, position the hexagonal file at a 90-degree angle to the guide bar. The bead should point upwards and run parallel to the markings on the tooth, automatically producing the ideal sharpening angle of 25 degrees. 

Hold the handle with one hand and guide the file along the tooth with the other, using forward strokes only. Lift the file up from the tooth on the backstroke to ensure that you file on the forward stroke only. Then adjust the depth gauge – See step 3 above for detailed instructions.

Softwood or hardwood? Adjusting the depth gauge optimally

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. 

A filing gauge is used to adjust the depth gauge on a STIHL saw 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.

How to sharpen a chainsaw with a file: more tips and tricks to sharpen a saw chain successfully

  • 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 2-in-1 Easyfile to sharpen the teeth of your saw chain and reset the depth gauge to the correct height at the same time.

Operating instructions for STIHL chainsaws

You can easily download the operating instructions for your STIHL chainsaw here.

Summary: How to sharpen a chainsaw

  • A blunt chainsaw makes your work harder and is less safe

  • Sharpening your chainsaw requires minimal preparation and is easy with the right tools

  • Use a suitable round saw chain file for sharpening the teeth of your chainsaw
  • You should also read the operating instructions for your chainsaw when carrying out maintenance work such as sharpening