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.

A STIHL MS 261 C-M petrol chainsaw with Light 04 guide bar clamped to a workbench, and bottle of STIHL MotoMix behind it
Close-up of STIHL chainsaw files and chain on a workbench with other tools visible in the background

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 chainsaw 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 the blade teeth on one side, or that they are not of an even length.

5.

The chainsaw chatters and bounces when sawing, which makes it difficult to use with precision.

A STIHL 261 C-M petrol chainsaw clamped to a workbench as a man wearing gloves uses a round file to sharpen the chain

Video instructions: how to file your chainsaw chain using the STIHL 2-in-1 EasyFile

Our video instructions show you how to sharpen the saw chain and adjust the depth gauge on your STIHL chainsaw at the same time, using the 2-in-1 EasyFile.

What is the depth gauge setting?

The depth gauge setting is the distance between the leading edge of the tooth top plate and the upper edge of the depth gauge. The larger the distance, the more wood is planed away by each tooth. This setting is reduced when you sharpen the chainsaw teeth, as you make the whole tooth shorter and change its shape.

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

Close-up of chainsaw cutting attachment and chain on a workbench Image source: SK-OILOMATIC_KETTE-IM-001

Filing aids for sharpening a chainsaw chain

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 chainsaw to make the process simpler. 

FF 1 File holder guide

View details about FF 1 File holder guide.Cutting Attachment Maintenance
Exclusive file holder guide for precise and easy file handling
AvailabilityThis item is only available at STIHL Approved Dealers.
£13.80

Filing vice S 260

View details about Filing vice S 260.Cutting Attachment Maintenance
Practical holster for carrying the file bracket
AvailabilityThis item is only available at STIHL Approved Dealers.
£20.70

FG 2 filing tool

View details about FG 2 filing tool.Cutting Attachment Maintenance
2 screw clamps required for attaching to the bench
AvailabilityThis item is only available at STIHL Approved Dealers.
£180.30

FG 3 filing tool

View details about FG 3 filing tool.Cutting Attachment Maintenance
Precision hand-filing tool for mounting onto a guide bar
AvailabilityThis item is only available at STIHL Approved Dealers.
£140.20

Guide bar leveller

View details about Guide bar leveller.Cutting Attachment Maintenance
Compact tool for removing burrs from the guide bar
AvailabilityThis item is only available at STIHL Approved Dealers.
£35.30
Close-up of a STIHL file holder guide being positioned on a STIHL Light 04 guide bar in a clamp

Sharpening with a saw chain file

The tool you need to sharpen the  teeth on a saw chain is a round file – you must make sure you use the right type and size of file for your chain, otherwise you may impair the cutting performance of your chainsaw.

The diameter of round file needed depends on the chain pitch of the saw chain you need to sharpen.

How to sharpen your chainsaw: choosing the right round file

Chains are assigned to specific chainsaw performance classes based on the chain pitch. On STIHL saw chains this is easily identifiable by means of a code on the depth gauge of each cutting tooth, which you can cross-refer with the STIHL saw chain file size chart provided below.

Close-up of saw chain links showing code identifying the chain pitch

If the number displayed on the tooth is no longer legible you may need to measure it using a chain control gauge. Alternatively, you could calculate it yourself: use a calliper to measure the distance from the middle of a rivet to the middle of the next rivet but one. Halve the result to determine the distance in millimetres. Chain pitch is always listed in inches, therefore you will need to convert the measurement - one millimetre equals 0.039 inches, meaning you need to multiply the measurement in millimetres by 0.039 to get the equivalent in inches. Then use the STIHL saw chain file size chart to look up the file diameter that fits the measurement (in inches). Your nearest STIHL dealer will also be happy to assist with this.

Code digit on the depth gauge Chain pitch Round file diameter
1 1/4" 4.0 mm
2 .325" 4.8 mm
3 3/8" 5.2 mm
4 .404" 5.5 mm
6 3/8" Picco 4.0 mm
7 1/4" Picco 3.2 mm

Close-up of calliper being used to measure chain pitch

Good to know

Saw chain files are different from workshop files and other files. They have a special surface structure, known as a file stroke, that makes them suitable for sharpening saw chains. You should never use other file types to sharpen your chainsaw.

How to sharpen a saw chain using a filing kit

How to sharpen a chainsaw: tips and tricks

  • Start by colouring in the tooth face of one tooth with a felt-tip pen. This helps you remove material evenly as you sharpen. After two to three file strokes, check the face: if the coloured pen has been uniformly removed, you’re filing correctly. If colour remains in places, check that you are using the correct saw chain file and that you are not moving the file too high or too low.
  • Do not keep working with a saw chain until it is completely blunt. Instead, sharpen lightly but regularly to keep your chainsaw functioning well.
  • Count the number of strokes you take with your file and apply the same number to each tooth. This way all the teeth end up the same length.
  • If you find that the teeth are shorter in one row, you have applied greater filing pressure to one side. Even out the length by applying one or two file strokes on the longer teeth.
  • Product tip: The 2-in-1 Easyfile enables you to sharpen your chainsaw teeth and restore the depth gauge to the correct height at the same time.

Operating instructions for STIHL chainsaws

You can download the instruction manual for your STIHL chainsaw here at your convenience.

Summary: how to sharpen your chainsaw

  • A blunt chainsaw is not only more difficult to use, but also less safe

  • Do a little preparation and ensure you have the right tools to sharpen your chainsaw

  • Use a suitable round saw chain file to sharpen the teeth on your chainsaw
  • We recommend reading the operating instructions for your chainsaw before you perform maintenance work on it or sharpen it