This post contains affiliate links.
Keeping a chainsaw chain sharp is an important aspect of chainsaw safety and efficiency. Sharpening a chainsaw is a skill that every chainsaw owner should have. A time may come when you need to sharpen your chainsaw in the field. Then you will need to know what degrees you should use to sharpen your chainsaw!
The sharpening angle for a chainsaw is at 30°. This provides the most versatile sharpening angle for a wide range of cutting tasks. An angle of 35° can be used to cut softwood, but the teeth will dull faster. A sharpening angle of 25° is used for cutting hardwood to keep the teeth sharp for longer.
Sharpening a chainsaw requires some knowledge regarding the subject, specifically, the tools to use and the methods to sharpen the chainsaw teeth. This includes the best angles to use when sharpening the chainsaw to ensure the efficiency of the cut. The sharpening angle for the chain can vary depending on the application the chainsaw is being used for.
What Sharpening Angle Should You Use For A Chainsaw?
Sharpening a chainsaw is important to maintain the chain’s cutting efficiency, reducing potential binding during the cut, limiting kickback, and reducing the wear and tear on the chainsaw motor and gears.
Sharpening a chainsaw chain is not difficult, but it does require some basic skills to perform the task correctly.
When sharpening the teeth on the chain, several angle choices have advantages and disadvantages when used in certain cutting applications.
Consequently, choosing the best sharpening angle requires knowledge about what wood you will be cutting.
When you hear people talking about chainsaw sharpening, most of the angles discussed will be the top plate angle. However, the other angles on the facets of the cutting tooth have a bearing on the chain’s overall performance.
If you are interested in using your chainsaw to mill boards check out my article, Is a Chainsaw mill worth it? Cost, Quality, and Time.
Best Chainsaw Top Plate Sharpening Angle
Chainsaw chains are manufactured for different cutting applications. This means that selecting the best sharpening angle for your chainsaw chain requires that you should follow the chain manufacturer’s recommendation for the best angle.
While you can adjust the cutting edge angle on the teeth, you may reduce the chain’s lifespan if this angle is outside the recommended angle.
The most common angles for the top plate are between 25° and 35°. While you can change the filing angel on some chains, it is best to stay within the recommended sharpening angles for the chain.
The most common general-purpose sharpening angle for the top plate is 30°. This angle will give you a long-lasting edge and one that is suitable for cutting a wider range of wood types.
Typically, an edge sharpened to 35° is suitable for cutting softwoods faster, more efficiently, and cleanly, but the edge will dull faster.
An edge sharpened to an angle of 25° will be slower in the cut, but the edge will stay sharp for longer. This makes this angle the more appropriate choice for cutting hardwoods.
Consequently, the 30° angle offers a middle-of-the-road average that will give a longer-lasting edge and a medium-cut speed. The 30° angle is the best angle to choose if you cut a variety of wood types than a single wood species.
Best Tools To Sharpen The Chainsaw Top Plate Or Tooth
The top plate is generally sharpened using a round chainsaw file. These files are different from other standard round files and come in different sizes.
Standard woodworking round files usually taper towards the tip of the file. This makes them unsuitable to be used to sharpen a chainsaw. The taper on this type of file will not allow you to maintain the correct sharpening angle for the chainsaw teeth.
A chainsaw file does not have this taper but is a constant diameter through the entire file length. This will cut consistently at the same angle as the chainsaw teeth are sharpened.
- A heavy-duty, compact, and compartmentalized case which keeps everything in place and...
- Round files, flat file, file guide, depth gauge tool and file handles help you maintain...
- Chainsaw wrench and mini screwdriver help you access all parts of your saw for...
Chainsaw files come in a range of diameters used to maintain the correct angle and depth when sharpening. The chainsaw itself will often have a number stamped into the tooth of the chainsaw, detailing which diameter file should be used to sharpen the saw.
The number is usually a single digit, called the depth gauge marking, such as the number 3. A depth gauge marking of 3 would indicate that a chainsaw file with a diameter of 5.2mm or 0.2-inches is the right file to use on the chain for sharpening.
Below I have tabulated some common depth gauge markings and the corresponding chainsaw file diameters.
Depth Guage Number | File Diameter In mm | File Diameter In Inches |
1 | 4.0mm | 0.157 inches |
2 | 4.8mm | 0.188 inches |
3 | 5.2mm | 0.2 inches |
4 | 5.5mm | 0.216 inches |
6 | 4.0mm | 0.157 inches |
7 | 3.2mm | 0.125 inches |
Vertical Angle For Sharpening the Top Plate Or Tooth
The vertical angle sharpening on the chainsaw cutting tooth is the angle the file is held in the vertical plane rather than the horizontal plane.
This file angle is achieved simultaneously as you create the 30° angle (or other relevant angles) in the horizontal plane. Thus, you are still using the round file for this process.
This will be the vertical tilt of the file while sharpening the cutting tooth. This vertical angle varies between chain manufacturers.
For example, most Husqvarna chainsaw chains require a vertical angle of 90°, while some Stihl chainsaw chains require a vertical angle of 85°.
Sharpening The Rakers Or Depth Gauges
The depth gauges or rakers are the metal hooks in front of each cutting tooth on the chainsaw. These rakers determine the depth at which the cutting tooth will cut.
If the raker is too high, the cutting teeth will not be able to bit deep enough into the wood, and cutting will be slow. The cutting teeth will bite too deeply into the wood if the raker is too low. This can cause kickback and cause the motor to work too hard, reducing the life of the chainsaw.
Consequently, the raker must be filed to the correct height for the cutting teeth. The best way to establish the correct height for the depth gauge or rakers is to use a file depth guide.
This guide is placed over the top of the chain to measure the height of the raker. If there is any portion of the raker sticking above the file guide, the raker should be filed until it is level with the top surface of the file guide.
There is no particular angle that the raker must be filed to, as it is rather a height adjustment rather than a sharpening. The raker can simply be filed until it is flush with the guide.
Once the raker is filed flat, there may be a sharp corner on the leading edge of the raker. This corner can be rounded off by using the flat file.
How To Maintain The Correct Filing Angles
One of the main challenges facing people new to chainsaw sharpening is maintaining correct angles during the process.
There are many methods to sharpen a chainsaw, but one of the simplest is by hand using a combination of a flat file and a round chainsaw file.
Can You Maintain Chainsaw Sharpening Angles By Eye?
It is certainly possible to maintain the correct filing angles while sharpening the chainsaw freehand. However, this requires some practice to get right, and you may mess up a few chains while getting the required experience.
One way of assistance to maintaining the correct angle is to follow some guidelines. Many chainsaw manufacturers put a guideline on the top surface of the cutting tooth to indicate the correct horizontal sharpening angle.
The line is easy to follow if you position yourself directly above the tooth being sharpened. From this vantage point above the chain, you will be able to keep the file parallel to the guideline mart on the top of the tooth and maintain the correct horizontal angle.
The vertical angle is relatively easy to maintain by feel. It is usually 90°, in which case the file must be flat, or it must be 85°, which is a slight angle off the 90°.
If the chain does not have guide marks on the tooth’s top surface, you can draw some guidelines on your vice to give you the common 25°, 30°, and 35° angles. As you work above the chain, you can look down on these guide marks and ensure you are keeping the file at the correct angle.
Once you become more familiar with these angles after several sharpening sessions, you will build muscle memory and be able to sharpen your chain without the use of the guidelines. However, it is best to use these guides to get the optimal cut, even if you have experience.
Use A Chainsaw Sharpening Kit To Maintain Angles
Most chainsaw and chain manufacturers realize that many chainsaw owners prefer to do their own sharpening. These manufacturers have produced chain sharpening kits that take all the guesswork out of the sharpening process and allow consistent results time after time.
These kits, such as the Husqvarna Chain Saw Sharpener File Kit, come with 2 round chainsaw files, 1 flat file, a roller file guide, and a depth gauge file guide.
The file guides allow you to select the required angle, position the guide on the chainsaw, and then use the file over the guide.
The roller guide is usually for use with the round file. It will be fixed in the correct position to provide the optimal sharpening angle in the horizontal and vertical planes. This makes it very easy to maintain the right sharpening angles without guessing or worrying about maintaining the angle during the file stroke.
The depth gauge file guide will be used with the flat file to establish the correct height for the depth gauge or rakers in front of each cutting tooth.
These sharpening kits are cost-effective, usually under $20, and compact enough to take out in the field with you so you can easily sharpen a chainsaw while you are out on the job.
It is important that the chainsaw is firm and does not move around during the sharpening process. This is easy enough to achieve if you have a vice at home, but it can be a bit more challenging out in the field. A stump vice is a handy tool used to secure the chainsaw bar firmly for sharpening. It has tines that can be driven into a tree stump to provide a secure base and a clamp to hold the chainsaw bar in place.
- Includes everything you need to file your chain
- Chain file kit for models 36, 41, 136, 137, 141 and 142
- Includes file handle, combination filing gauge, 2 round files, and 1 flat file for depth...
Use A Professional Chainsaw Sharpening Service
Some chainsaw owners prefer sending their chainsaw chains to a professional sharpening service for sharpening.
These chainsaw owners would generally have multiple chains and will swap a dull chain out for a sharp chain while they send the dull chain to a professional for sharpening.
While this can be a suitable strategy for a large commercial concern, it is often a logistical problem rather than of a financial problem to make use of such a service.
Professional chainsaw sharpening services usually use power tools specifically made for sharpening the chains and can be set to all the correct angles for the specific chain.
The average price for a professional chainsaw sharpening usually averages around $15 per chain. Buying your own sharpening kit will cost you about the same price, and you will be able to sharpen many chains with the kit.
How Often Can A Chain Saw Be Sharpened?
Sharpening a chainsaw chain removes metal from the teeth every time sharpening is performed. As a result, a chainsaw chain can only be sharpened a limited number of times before requiring replacement.
The most common frequency is between 3 to 5 sharpenings before replacing the chain. However, doing small touchups here and there to maintain a sharp edge will keep the cutting teeth in good shape. This will reduce the requirement for frequent aggressive sharpening that will limit the life of the chain.
Chainsaw Sharpening Tips
You can follow a few basic tips and tricks that will help you sharpen your chainsaw more effectively and keep your chainsaw files in good shape.
- Always clean the chain before sharpening. Use a brush to remove dirt and wood chips before sharpening the teeth. The dirt will clog the file and make it less effective.
- A chainsaw file only cuts in one direction. A chainsaw file cuts on the push stroke, not the pull stroke. The push stroke should have pressure, but pressure must be lifted when the file is returned to the starting position. Trying to cut with the pull stroke will dull the file.
- Sharpen all the chain’s teeth at the same time. This will promote even wear across the teeth on the chain and put less strain on the motor.
Final Thoughts
The most common angle for sharpening a chain saw is at a 30° angle. For frequent softwood cutting, an angle of 35° can be used. For frequent hardwood cutting with a chainsaw, an angle of 25° can be used to sharpen the chain.
Most people use the 30° average since this provides the most versatile sharpening angle for a wider range of cutting tasks.