Stihl Chainsaw File Sizes Guide (3 Pro Tips for Sharper Cuts)

Stihl Chainsaw File Sizes Guide (3 Pro Tips for Sharper Cuts)

As someone who’s spent countless hours in the woods, from felling towering pines to bucking logs for winter warmth, I can tell you firsthand: a sharp chainsaw is not just about speed; it’s about safety, efficiency, and the sheer satisfaction of a clean cut. Trying to force a dull chain through wood is a recipe for kickback, strain, and frustration.

Finding the right file size for your Stihl chainsaw can be a bit daunting. There are a lot of numbers and technical jargon, but don’t worry, I’m here to simplify it all.

Understanding the Importance of File Size

The file size you choose directly impacts the cutting angle and depth of your saw chain’s teeth. Using the wrong size can lead to:

• Dull Cuts: An incorrect file size won’t properly sharpen the cutting edge, resulting in slow and inefficient cutting.
• Chain Damage: Using too large a file can damage the teeth, weakening the chain and reducing its lifespan.
• Kickback: An improperly sharpened chain is more prone to kickback, a dangerous situation where the saw jumps back towards the operator.
• Uneven Sharpening: This leads to vibrations, poor cutting performance, and premature wear.

Identifying Your Stihl Chain Type and Pitch

Before you even think about grabbing a file, you need to know your chain’s specifications. The two key pieces of information are the chain type and pitch. This information is usually stamped on the drive link of your chain or is listed in your chainsaw’s manual.

• Chain Type: Stihl offers various chain types, each designed for specific cutting applications. Examples include Rapid Micro (RM), Rapid Super (RS), and Picco Micro (PM).
• Pitch: The pitch is the distance between any three consecutive rivets on the chain, divided by two. Common pitches are .325″, 3/8″, and .404″.

Why is this important? Because the chain type and pitch dictate the size of the file you need.

Stihl Chainsaw File Size Chart

Here’s a handy chart to get you started. Remember, this is a general guide, and it’s always best to consult your chainsaw’s manual for the most accurate information:

Important Note: This chart assumes you’re using round files for sharpening the cutting teeth and a flat file for adjusting the depth gauges (rakers).

Pro Tip #1: The “Feel” Test

While the chart provides a good starting point, I’ve found that sometimes the best way to determine the correct file size is by “feel.”

Hold the file against the cutting tooth. The file should sit comfortably within the tooth’s gullet (the curved area in front of the cutter). It shouldn’t be too small, leaving a gap, nor should it be too large, protruding beyond the tooth’s edge. The goal is to have the file make full contact with the cutting edge without altering the shape of the tooth.

I once worked on a logging project in the Pacific Northwest, felling massive Douglas firs. The conditions were tough – dense wood, frequent rain, and demanding deadlines. We were sharpening our chains multiple times a day. One of the older loggers, a grizzled veteran named Earl, taught me this “feel” test. He said, “Son, the steel will tell you what it needs.” He was right. Over time, you develop a sense for the right fit.

Choosing the Right File Type and Handle

Beyond the size, the type of file matters. For sharpening the cutting teeth, you’ll primarily use a round file. These files are specifically designed to fit the curved shape of the tooth. For adjusting the depth gauges (rakers), you’ll need a flat file.

• File Quality: Invest in high-quality files. Cheap files dull quickly and can damage your chain. Stihl files are generally a good choice, but other reputable brands like Pferd and Vallorbe are also excellent.
• File Handle: A comfortable and secure file handle is crucial for control and safety. Choose a handle that fits your hand well and provides a good grip. I prefer wooden handles, but plastic handles are also available.

The Sharpening Process: Step-by-Step

Now that you have the right file, let’s get to the sharpening process.

1. Secure the Chainsaw: Properly secure your chainsaw. I prefer using a vise specifically designed for chainsaw sharpening. This keeps the saw stable and allows you to focus on sharpening.
2. Identify the Shortest Cutter: Examine your chain and identify the shortest cutter. This will be your guide for sharpening all the other cutters to the same length.
3. Position the File: Hold the file at the correct angle. Most Stihl chains have markings on the cutters to indicate the correct filing angle. A file guide can be helpful for maintaining a consistent angle.
4. Sharpen Each Cutter: Using smooth, even strokes, file each cutter from the inside out. Maintain consistent pressure and angle. Count the number of strokes you use on the shortest cutter and use the same number on all the other cutters.
5. Check for Burrs: After sharpening, check for burrs (small, sharp edges) on the cutters. Use a fine-grit stone to remove any burrs.
6. Adjust Depth Gauges (Rakers): After several sharpenings, the depth gauges (rakers) may need to be lowered. Use a flat file and a depth gauge tool to adjust the rakers to the correct height. The correct height is usually stamped on the chain.

Pro Tip #2: Depth Gauge (Raker) Adjustment is Key

Many people focus solely on sharpening the cutting teeth, but the depth gauges (rakers) are just as important. The depth gauges control how much wood the cutters can bite into. If the depth gauges are too high, the chain will cut slowly, even if the cutters are sharp. If they’re too low, the chain will grab and kickback.

I learned this the hard way during a firewood cutting project in the Adirondacks. I had meticulously sharpened my chain, but it still wouldn’t cut properly. I was frustrated and ready to give up. Then, an old-timer stopped by and pointed out that my depth gauges were too high. He showed me how to adjust them with a flat file and a depth gauge tool. The difference was night and day! Suddenly, the chain was cutting like butter.

Here’s a simple way to remember it: Think of the cutting teeth as the “teeth” and the depth gauges as the “lips.” The “lips” need to be at the right height to allow the “teeth” to do their job effectively.

Maintaining Your Files

Just like your chainsaw, your files need to be properly maintained.

• Clean Your Files: Use a file card (a special brush for cleaning files) to remove metal filings from the file’s teeth. This will keep the file sharp and prevent it from clogging.
• Store Your Files Properly: Store your files in a dry place to prevent rust. Avoid banging them against hard surfaces, as this can damage the teeth.
• Replace Dull Files: Files don’t last forever. Once a file becomes dull, it’s time to replace it. Using a dull file is a waste of time and can damage your chain.

Pro Tip #3: Sharpening Frequency and Wood Type

The frequency with which you need to sharpen your chain depends on several factors, including the type of wood you’re cutting, the condition of the wood (e.g., dirty, sandy), and your cutting technique.

• Softwoods: Softwoods like pine and fir are generally easier on chains and require less frequent sharpening.
• Hardwoods: Hardwoods like oak and maple are tougher on chains and require more frequent sharpening.
• Dirty Wood: Cutting dirty or sandy wood will dull your chain much faster.

As a general rule, I sharpen my chain every time I refuel my chainsaw. This ensures that the chain is always sharp and ready to go. However, if I’m cutting dirty wood or hardwoods, I may sharpen it more frequently.

I remember a project where I was clearing some land that had been used as a dumping ground. The wood was full of dirt, rocks, and even pieces of metal. I was sharpening my chain every few minutes! It was a frustrating experience, but it taught me the importance of sharpening frequency.

Safety First!

Sharpening a chainsaw can be dangerous if you’re not careful. Always wear gloves and eye protection. Keep your hands away from the chain. And never sharpen a chain while the chainsaw is running.

Troubleshooting Common Sharpening Problems

• Chain Cuts to One Side: This usually indicates that the cutters on one side of the chain are duller than the cutters on the other side. Sharpen the duller cutters until they’re the same length as the sharper cutters.
• Chain Cuts Slowly: This could be due to dull cutters, high depth gauges, or a worn-out chain.
• Chain Kicks Back: This is a dangerous situation that can be caused by improperly sharpened cutters, low depth gauges, or cutting with the tip of the bar.

Beyond the Basics: Advanced Sharpening Techniques

Once you’ve mastered the basic sharpening techniques, you can explore more advanced methods, such as using a chainsaw sharpener. These tools can help you sharpen your chain more quickly and accurately. However, they can also be expensive, so it’s important to weigh the pros and cons before investing in one.

Another advanced technique is to use different file angles for different types of wood. For example, you might use a steeper file angle for hardwoods to create a more aggressive cutting edge.

The Satisfaction of a Sharp Chain

There’s nothing quite like the feeling of a perfectly sharpened chainsaw slicing through wood effortlessly. It’s a testament to your skill and attention to detail. And it makes the job of cutting wood safer, easier, and more enjoyable.

Conclusion

Sharpening your Stihl chainsaw is an essential skill for anyone who works with wood. By understanding the importance of file size, mastering the sharpening process, and following these pro tips, you can keep your chain cutting like new and enjoy the satisfaction of a job well done. Remember, a sharp chain is a safe chain, and a safe chain makes for a happy woodworker. So, grab your files, get to work, and experience the difference a sharp chain can make!

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