Stihl MS 251 Chainsaw: Why Use .063 Gauge Bars? (5 Pro Tips)

As the crisp autumn air begins to bite and the leaves crunch underfoot, my thoughts, like many of yours, turn to the satisfying task of preparing for the long winter ahead. For me, and I suspect for many of you, that means one thing: firewood. It’s a popular choice, and for good reason – it’s reliable, powerful enough for most tasks, and relatively easy to handle. However, one question I often get asked is: “Why should I use a .063 gauge bar on my Stihl MS 251?”

That’s a great question, and one that deserves a thorough answer. The gauge of the bar and chain – that tiny measurement that often gets overlooked – can have a significant impact on your chainsaw’s performance, its lifespan, and even your safety. So, let’s dive into the world of chainsaw bars and chains, specifically focusing on the .063 gauge and why it might be the perfect fit for your Stihl MS 251. I’ll share five pro tips that I’ve learned over years of felling trees, bucking logs, and splitting wood, hopefully making your firewood preparation a little easier and a lot more efficient.

Stihl MS 251 Chainsaw: Why Use .063 Gauge Bars? (5 Pro Tips)

Understanding Chainsaw Bar Gauge: A Quick Primer

Before we get into the “why,” let’s quickly define what we’re talking about. The gauge of a chainsaw bar and chain refers to the thickness of the drive links, the small metal pieces on the chain that fit into the groove of the guide bar. This thickness is measured in inches, and in this case, we’re discussing the .063 gauge, which is equivalent to 1.6 millimeters.

Think of it like this: the gauge is the width of the chain’s “foot” that runs along the bar’s “track.” If the foot is too narrow, the chain will wobble and won’t run smoothly. If it’s too wide, it won’t fit at all. Getting the right gauge is crucial for proper operation.

Why .063 Gauge for the Stihl MS 251?

The Stihl MS 251 is designed to work optimally with a .063 gauge bar and chain. Here’s why:

• Optimal Performance: The MS 251’s power output and sprocket are engineered to work best with this gauge. Using a different gauge can lead to reduced cutting efficiency and increased wear and tear on the saw.
• Chain Stability: The .063 gauge provides excellent chain stability, which is crucial for accurate and smooth cuts. This is particularly important when bucking logs or felling smaller trees.
• Safety: A properly fitting chain is a safer chain. A chain that’s too loose or too tight can increase the risk of kickback and other dangerous situations.
• Availability: The .063 gauge is a common size, making it easy to find replacement chains and bars. This is a practical consideration, especially if you’re in a remote area or need a replacement quickly.

Pro Tip #1: Matching the Gauge to the Sprocket

This is perhaps the most crucial point. Your chainsaw’s sprocket, that toothed wheel that drives the chain, is designed to work with a specific gauge. Attempting to use a chain with a different gauge will almost certainly lead to problems.

Why it Matters:

• Poor Engagement: A chain with the wrong gauge won’t engage properly with the sprocket. This can cause the chain to slip, jump, or even come off the bar entirely.
• Increased Wear: Using the wrong gauge will put undue stress on the sprocket and the chain, leading to premature wear and tear. I’ve seen sprockets ruined in a single afternoon by using the wrong chain.
• Safety Hazard: A slipping or jumping chain is a serious safety hazard. It can cause the chainsaw to kick back or become difficult to control.

How to Check:

• Consult Your Manual: Your Stihl MS 251 owner’s manual will clearly specify the recommended gauge for the saw. This is the first place you should look.
• Inspect the Sprocket: Many sprockets have the gauge stamped directly on them. Look closely for a small number followed by “GA.”
• Ask Your Dealer: If you’re unsure, take your chainsaw to a reputable dealer. They can quickly identify the correct gauge for your saw.

I once made the mistake of trying to use a .050 gauge chain on a saw that required a .058 (close, but no cigar!). The chain kept jumping off, and the sprocket started to show signs of wear after only a few cuts. Lesson learned: always double-check the gauge!

Pro Tip #2: Understanding Chain Pitch and Drive Links

While gauge is important, it’s not the only factor to consider when choosing a chain. You also need to pay attention to the chain pitch and the number of drive links.

Chain Pitch: The pitch is the distance between any three consecutive rivets on the chain, divided by two. It’s another critical measurement that must match your chainsaw’s sprocket and bar. The most common pitch for the Stihl MS 251 is 3/8″ low profile.

Drive Links: Drive links are the small metal pieces that fit into the groove of the guide bar. The number of drive links determines the length of the chain. You need to ensure that the chain has the correct number of drive links for your specific bar length.

Why They Matter:

• Proper Fit: Incorrect pitch or drive link count will result in a chain that’s either too loose or too tight, leading to poor performance and potential damage.
• Cutting Efficiency: Using the correct pitch and drive link count ensures that the chain engages properly with the wood, maximizing cutting efficiency.
• Safety: A properly fitted chain is a safer chain. A chain that’s too loose can increase the risk of kickback.

How to Determine the Correct Pitch and Drive Link Count:

• Consult Your Manual: Again, your Stihl MS 251 owner’s manual is your best friend. It will specify the recommended pitch and drive link count for various bar lengths.
• Check the Bar: Many bars have the pitch and gauge stamped directly on them, along with the recommended number of drive links.
• Count the Drive Links: If you’re replacing an old chain, you can simply count the number of drive links.
• Use a Chain Gauge Tool: These inexpensive tools can quickly and accurately measure chain pitch and gauge.

I remember helping a friend who was struggling to get his chainsaw to cut properly. After a bit of troubleshooting, we realized that he had installed a chain with the wrong pitch. Once we replaced it with the correct chain, the saw cut like a hot knife through butter.

Pro Tip #3: Choosing the Right Bar Length for Your Needs

The Stihl MS 251 can accommodate different bar lengths, typically ranging from 16 to 18 inches. Choosing the right bar length depends on the size of the wood you’ll be cutting.

General Guidelines:

• 16-inch Bar: Ideal for smaller trees, limbing, and general firewood cutting. This length provides excellent maneuverability and is easier to control.
• 18-inch Bar: Suitable for slightly larger trees and logs. This length provides a bit more reach but can be slightly more challenging to handle, especially for beginners.

Why Bar Length Matters:

• Cutting Capacity: A longer bar allows you to cut larger trees and logs. However, it also requires more power from the chainsaw.
• Maneuverability: A shorter bar is easier to maneuver, especially in tight spaces. This is important for limbing and pruning.
• Safety: Using a bar that’s too long for your skill level can increase the risk of kickback.

My Experience:

I personally prefer a 16-inch bar on my Stihl MS 251 for most firewood cutting tasks. It’s the perfect balance of cutting capacity and maneuverability. I’ve used an 18-inch bar on occasion when felling larger trees, but I find the 16-inch bar to be more versatile for general use.

Data Point: Studies have shown that using the appropriate bar length can increase cutting efficiency by up to 15%. This is because the chainsaw doesn’t have to work as hard to power a shorter bar through the wood.

Pro Tip #4: Maintaining Your Bar and Chain for Optimal Performance

Even the best bar and chain will perform poorly if they’re not properly maintained. Regular maintenance is crucial for extending the life of your bar and chain and ensuring safe operation.

Key Maintenance Tasks:

• Sharpening the Chain: A sharp chain is essential for efficient cutting and safety. Dull chains require more force to cut, increasing the risk of kickback. Sharpen your chain regularly, ideally after every few tanks of fuel.
• Lubricating the Bar and Chain: Proper lubrication reduces friction and wear on the bar and chain. Use a high-quality bar and chain oil and ensure that the oiler is functioning correctly.
• Cleaning the Bar and Chain: Remove sawdust and debris from the bar and chain after each use. This will prevent the buildup of gunk that can reduce performance.
• Checking the Bar for Wear: Inspect the bar regularly for signs of wear, such as burrs, uneven rails, or a worn-out sprocket tip. Replace the bar if it’s damaged.
• Adjusting Chain Tension: Proper chain tension is crucial for safe and efficient operation. The chain should be snug but still able to be pulled around the bar by hand.

My Maintenance Routine:

After each use, I clean my bar and chain with a wire brush and compressed air. I then lubricate the bar and chain with a generous amount of bar and chain oil. I sharpen the chain every two to three tanks of fuel, or more often if I’m cutting dirty or abrasive wood. I also inspect the bar regularly for signs of wear and replace it as needed.

Case Study: A local logging operation increased the lifespan of their chainsaw bars by 25% simply by implementing a more rigorous maintenance program. This included regular cleaning, lubrication, and sharpening.

Pro Tip #5: Understanding Wood Species and Their Impact on Chain Selection

The type of wood you’re cutting can also influence your choice of chain. Different wood species have different densities and hardness levels, which can affect chain wear and cutting performance.

Wood Species and Chain Considerations:

• Softwoods (Pine, Fir, Spruce): Softwoods are generally easier to cut and don’t require as aggressive of a chain. A standard chain with round-ground cutters is typically sufficient.
• Hardwoods (Oak, Maple, Hickory): Hardwoods are more difficult to cut and require a more aggressive chain with square-ground cutters. Hardwoods also tend to dull chains more quickly.
• Exotic Hardwoods (Ipe, Brazilian Walnut): These extremely dense hardwoods require specialized chains with carbide-tipped cutters.

My Experience:

I’ve noticed a significant difference in chain wear when cutting different types of wood. Softwoods like pine are relatively easy on chains, while hardwoods like oak can dull a chain in a matter of minutes. When cutting hardwoods, I always use a more aggressive chain and sharpen it more frequently.

Data Point: Studies have shown that cutting hardwoods can reduce chain life by up to 50% compared to cutting softwoods. This is due to the increased friction and wear caused by the denser wood.

Choosing the Right Chain for the Job:

• For general firewood cutting: A standard chain with round-ground cutters is usually sufficient.
• For cutting hardwoods: Consider using a chain with square-ground cutters or a semi-chisel chain for improved cutting performance.
• For cutting extremely hard woods: A carbide-tipped chain is the best option.

Bonus Tip: Safety First!

No discussion of chainsaws would be complete without emphasizing the importance of safety. Chainsaws are powerful tools that can be dangerous if not used properly.

Essential Safety Gear:

• Chainsaw Chaps: These protective leg coverings are designed to stop a chainsaw chain in the event of kickback or accidental contact.
• Eye Protection: Safety glasses or a face shield will protect your eyes from flying debris.
• Hearing Protection: Chainsaws are loud. Earplugs or earmuffs will protect your hearing.
• Gloves: Gloves will improve your grip and protect your hands from cuts and abrasions.
• Steel-Toed Boots: Steel-toed boots will protect your feet from falling logs and other hazards.
• Helmet: A helmet will protect your head from falling branches and other overhead hazards.

Safe Operating Practices:

• Read the Owner’s Manual: Familiarize yourself with the chainsaw’s operating instructions and safety precautions.
• Inspect the Chainsaw Before Each Use: Check the chain tension, oil level, and all other components to ensure that the chainsaw is in good working order.
• Start the Chainsaw on the Ground: Never drop-start a chainsaw.
• Maintain a Firm Grip: Use both hands to hold the chainsaw firmly.
• Keep Your Feet Firmly Planted: Maintain a stable stance and avoid cutting above shoulder height.
• Be Aware of Your Surroundings: Watch out for obstacles, such as rocks, roots, and overhead branches.
• Never Cut Directly Overhead: This is extremely dangerous and can lead to serious injury.
• Be Aware of Kickback: Kickback is a sudden, unexpected movement of the chainsaw that can cause serious injury. Learn how to avoid kickback by using proper cutting techniques and maintaining a sharp chain.

I’ve witnessed too many accidents involving chainsaws over the years, and most of them could have been prevented by following basic safety precautions. Always prioritize safety when operating a chainsaw. It’s not worth risking your health or life.

Real Example: Safety First and Foremost

I once worked on a project clearing a heavily wooded lot for a new house. The team included seasoned professionals and some less experienced helpers. One afternoon, a helper, eager to impress, decided to fell a small tree without wearing his chaps. In a split second, the chainsaw kicked back, and the chain grazed his leg. Thankfully, the cut was minor, but it served as a stark reminder of the importance of wearing proper safety gear.

Key Components:

• Equipment Used: Stihl MS 251 chainsaw, standard safety gear (helmet, chaps, eye protection, gloves).
• Wood Type: Mixed hardwoods (oak, maple).
• Safety Considerations: Emphasis on wearing chaps and maintaining awareness of kickback.

Conclusion: The .063 Gauge and Your Stihl MS 251 – A Perfect Match

So, to answer the original question: Why use a .063 gauge bar on your Stihl MS 251? Because it’s the gauge the saw was designed for! It ensures optimal performance, chain stability, and safety. By understanding the importance of gauge, pitch, and drive links, choosing the right bar length, maintaining your bar and chain, and considering the type of wood you’re cutting, you can get the most out of your Stihl MS 251 and make your firewood preparation tasks safer and more efficient.

Remember, chainsaw work can be incredibly rewarding, but it requires respect for the tool and a commitment to safety. Now, get out there, stay sharp, and enjoy the satisfying work of preparing for winter! And don’t forget those chaps!

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