MS 391 Stihl Chainsaw Tips (5 Pro Woodcutting Secrets)

Let’s face it, spending time outdoors, engaging in physical activity, and connecting with nature is not just a hobby; it’s an investment in your well-being. The scent of freshly cut wood, the satisfying thunk of a log splitting, and the warmth of a crackling fire – these are experiences that soothe the soul and invigorate the body. And while wielding a chainsaw might seem daunting at first, with the right knowledge and techniques, it can become a rewarding and even therapeutic activity.

I’ve spent years immersed in the world of wood processing, from felling trees in the dense forests of the Pacific Northwest to meticulously preparing firewood for the long winters of New England. Along the way, I’ve learned some invaluable lessons – lessons that have saved me time, energy, and even a few trips to the emergency room. Today, I’m eager to share five pro woodcutting secrets, specifically tailored for users of the MS 391 Stihl chainsaw, that will elevate your wood processing game and keep you safe while you’re at it.

1. Mastering Chainsaw Calibration: The Key to Peak Performance

A well-calibrated chainsaw isn’t just about efficiency; it’s about safety. A chainsaw that’s running too lean or too rich can overheat, damage the engine, and even cause a dangerous kickback. This is where understanding the nuances of carburetor adjustment becomes crucial.

My Story: I remember one particularly frustrating autumn when I was preparing firewood for the winter. My old chainsaw, a different model than the MS 391, was constantly bogging down, spewing black smoke, and generally making my life miserable. I spent days tinkering with it, replacing parts, and consulting online forums, but nothing seemed to work. Finally, a seasoned logger friend came over and, within minutes, diagnosed the problem: a poorly adjusted carburetor. He showed me the proper way to fine-tune the high and low-speed jets, and suddenly, the chainsaw roared back to life. It was a game-changer, and I vowed to never underestimate the importance of proper calibration again.

Technical Details:

The MS 391 Stihl chainsaw features a carburetor with three adjustment screws:

L (Low-Speed Jet): Controls the fuel mixture at idle and low speeds.
H (High-Speed Jet): Controls the fuel mixture at high speeds.
LA (Idle Speed Screw): Controls the engine’s idle speed.

Calibration Procedure:

Warm-up: Start the chainsaw and let it idle for a few minutes to warm up the engine.
Idle Speed Adjustment: Turn the LA screw clockwise to increase the idle speed or counter-clockwise to decrease it. The ideal idle speed is around 2,800 RPM. You should be able to hear the chain not moving on the bar.
Low-Speed Adjustment: With the engine idling, slowly turn the L screw clockwise until the engine starts to bog down. Then, slowly turn the L screw counter-clockwise until the engine runs smoothly. The ideal setting is usually between 1 and 1.5 turns out from fully closed.
High-Speed Adjustment: This is the trickiest part. You’ll need to make a test cut in a piece of wood and listen to the engine. If the engine is running too lean (screaming sound), turn the H screw counter-clockwise to richen the mixture. If the engine is running too rich (bogging down), turn the H screw clockwise to lean the mixture. The ideal setting is usually between 1 and 1.5 turns out from fully closed.

Important Considerations:

Altitude: Carburetor adjustments may need to be tweaked based on altitude. Higher altitudes require a leaner fuel mixture.
Fuel Type: Always use the recommended fuel-to-oil ratio specified by Stihl (typically 50:1).
Safety: Wear appropriate safety gear, including eye protection and hearing protection, when calibrating your chainsaw.
Manufacturer Specifications: Always consult the MS 391 Stihl chainsaw owner’s manual for specific calibration instructions and safety guidelines.

Data Point:

A study by the USDA Forest Service found that properly calibrated chainsaws consume up to 15% less fuel than poorly calibrated chainsaws. This translates to significant cost savings and reduced emissions over the lifespan of the tool.

Practical Tip:

Invest in a tachometer to accurately measure the engine’s RPM during calibration. This will help you fine-tune the adjustments and ensure optimal performance.

2. The Art of Wood Selection: Knowing Your Hardwoods from Your Softwoods

Not all wood is created equal. Understanding the properties of different wood species is crucial for efficient woodcutting and firewood preparation. This knowledge will not only make your job easier but also ensure that you’re using the right wood for the right purpose.

My Story: I once made the mistake of trying to heat my home with a load of freshly cut poplar. The poplar burned quickly, produced very little heat, and left behind a mountain of ash. It was a complete waste of time and energy. That experience taught me a valuable lesson: knowing your hardwoods from your softwoods is essential for efficient firewood preparation.

Technical Details:

Wood species are generally classified as either hardwoods or softwoods. These classifications are based on the tree’s botanical structure, not necessarily the wood’s actual hardness.

Hardwoods: Typically deciduous trees with broad leaves that shed annually. Hardwoods are generally denser and burn longer than softwoods. Examples include oak, maple, ash, birch, and cherry.
Softwoods: Typically coniferous trees with needles that remain green year-round. Softwoods are generally less dense and burn faster than hardwoods. Examples include pine, fir, spruce, and cedar.

Wood Selection Criteria:

Heat Value: Hardwoods generally have a higher heat value than softwoods. This means they produce more heat per unit volume.
Burning Time: Hardwoods burn longer than softwoods, requiring less frequent reloading of the fire.
Smoke Production: Some wood species produce more smoke than others. Drier wood produces less smoke.
Seasoning Time: Hardwoods typically take longer to season (dry) than softwoods.
Splitting Difficulty: Some wood species are easier to split than others. Straight-grained wood is generally easier to split than knotty wood.

Data Points:

Oak has a heat value of approximately 28 million BTU per cord, while pine has a heat value of approximately 20 million BTU per cord.
Hardwoods typically require 12-24 months to season properly, while softwoods may only require 6-12 months.
The ideal moisture content for firewood is between 15% and 20%.

Practical Tips:

Use a wood moisture meter to accurately measure the moisture content of your firewood.
Stack your firewood in a well-ventilated area to promote faster drying.
Avoid burning green wood, as it produces excessive smoke and creosote buildup in your chimney.

Case Study:

In a study conducted by the University of Maine, researchers compared the burning performance of different wood species. They found that oak produced the most heat and burned the longest, while poplar produced the least heat and burned the fastest. The study also found that properly seasoned wood produced significantly less smoke and creosote than green wood.

3. Precision Felling Techniques: Mastering the Hinge

Felling a tree is a complex and potentially dangerous task. It requires careful planning, precise execution, and a thorough understanding of tree behavior. Mastering the hinge is crucial for controlling the direction of the fall and ensuring a safe and predictable outcome.

My Story: I once witnessed a near-disaster when a novice logger attempted to fell a large oak tree without properly understanding the hinge. He made a deep back cut, leaving a thin and uneven hinge. As the tree began to fall, the hinge snapped prematurely, causing the tree to twist and fall in an unexpected direction. Luckily, no one was injured, but it was a stark reminder of the importance of precision felling techniques.

Technical Details:

The hinge is the strip of wood left uncut between the felling cut and the back cut. It acts as a rudder, guiding the tree’s fall in the desired direction.

Felling Procedure:

Assess the Tree: Evaluate the tree’s lean, wind direction, and any potential hazards in the surrounding area.
Plan the Fall: Determine the desired direction of fall and clear any obstacles in the path.
Make the Notch: Cut a notch on the side of the tree facing the desired direction of fall. The notch should be approximately one-fifth of the tree’s diameter.
Make the Felling Cut: Cut horizontally into the tree on the same side as the notch, stopping just before the notch.
Make the Back Cut: Cut horizontally into the tree from the opposite side of the notch, leaving a hinge of approximately one-tenth of the tree’s diameter.
Insert Wedges: Insert felling wedges into the back cut to help push the tree over.
Monitor the Fall: As the tree begins to fall, move to a safe location and monitor its descent.

Hinge Specifications:

Thickness: The hinge should be approximately one-tenth of the tree’s diameter.
Width: The hinge should be at least 80% of the tree’s diameter.
Uniformity: The hinge should be uniform in thickness and width to ensure a controlled fall.

Safety Considerations:

Always wear appropriate safety gear, including a hard hat, eye protection, hearing protection, and steel-toed boots.
Never fell a tree alone. Always have a spotter present to monitor the fall and warn of any potential hazards.
Be aware of your surroundings and avoid felling trees in windy conditions or near power lines.

Data Point:

A study by the Occupational Safety and Health Administration (OSHA) found that improper felling techniques are a leading cause of logging accidents.

Practical Tip:

Practice your felling techniques on smaller trees before attempting to fell larger trees.
Use a felling lever or a pulling rope to help guide the tree’s fall in the desired direction.

4. Chain Sharpening Secrets: Maintaining a Razor-Sharp Edge

A dull chainsaw is not only inefficient but also dangerous. It requires more force to cut through wood, increasing the risk of kickback and operator fatigue. Maintaining a razor-sharp chain is essential for safe and efficient woodcutting.

My Story: I used to dread sharpening my chainsaw chain. I thought it was a tedious and time-consuming task, and I often put it off until the chain was so dull that it was practically useless. Then, I discovered the secret to efficient chain sharpening: using the right tools and techniques. Now, I actually enjoy sharpening my chain, and I can keep it razor-sharp with minimal effort.

Technical Details:

A chainsaw chain consists of numerous cutting teeth, each with a specific angle and depth. Maintaining these angles and depths is crucial for optimal cutting performance.

Sharpening Procedure:

Secure the Chainsaw: Secure the chainsaw in a vise or on a stump to prevent it from moving during sharpening.
Identify the Correct File Size: Use a chainsaw file that is the correct size for your chain. The file size is typically stamped on the chain or in the owner’s manual.
Maintain the Correct Angle: Hold the file at the correct angle relative to the cutting tooth. This angle is typically marked on the file guide.
File Each Tooth Evenly: File each tooth evenly, using smooth and consistent strokes.
Check the Depth Gauges: Use a depth gauge tool to check the height of the depth gauges. File the depth gauges down if they are too high.
Deburr the Chain: Use a flat file to remove any burrs from the cutting teeth.

Chain Sharpening Tools:

Chainsaw File: A round file used to sharpen the cutting teeth.
File Guide: A tool that helps maintain the correct angle during sharpening.
Depth Gauge Tool: A tool used to check the height of the depth gauges.
Flat File: A file used to remove burrs from the cutting teeth.
Vise: A tool used to secure the chainsaw during sharpening.

Data Points:

A sharp chainsaw chain can cut through wood up to 50% faster than a dull chainsaw chain.
A sharp chainsaw chain reduces the risk of kickback and operator fatigue.

Practical Tips:

Sharpen your chainsaw chain after every few hours of use.
Use a chainsaw sharpener to make the sharpening process easier and more accurate.
Always wear gloves and eye protection when sharpening your chainsaw chain.

Case Study:

In a study conducted by Stihl, researchers compared the cutting performance of sharp and dull chainsaw chains. They found that sharp chains required significantly less force to cut through wood, resulting in reduced operator fatigue and increased productivity. The study also found that sharp chains were less likely to kick back, reducing the risk of accidents.

5. Firewood Preparation: Splitting and Stacking for Optimal Drying

Preparing firewood is more than just chopping wood; it’s a science. Proper splitting and stacking techniques are essential for ensuring that your firewood dries quickly and efficiently, maximizing its heat value and minimizing smoke production.

My Story: I used to haphazardly split and stack my firewood, resulting in slow drying times and a lot of wasted effort. The wood would often rot before it had a chance to dry properly, and I would end up burning damp, smoky logs. Then, I learned the importance of proper splitting and stacking techniques. Now, I can prepare a winter’s worth of firewood in a fraction of the time, and I can be confident that it will be dry and ready to burn when I need it.

Technical Details:

The goal of firewood preparation is to maximize the surface area of the wood exposed to air, allowing moisture to evaporate quickly.

Splitting Techniques:

Use the Right Tool: Use a splitting axe or a hydraulic log splitter to split the wood.
Split Along the Grain: Split the wood along the grain to make the process easier.
Split into Manageable Sizes: Split the wood into pieces that are easy to handle and stack.
Avoid Splitting Green Wood: Green wood is more difficult to split than seasoned wood.

Stacking Techniques:

Choose a Sunny and Well-Ventilated Location: Stack the firewood in a location that receives plenty of sunlight and has good air circulation.
Elevate the Wood: Elevate the wood off the ground to prevent moisture from wicking up from the soil.
Stack the Wood Loosely: Stack the wood loosely to allow air to circulate freely.
Cover the Top of the Stack: Cover the top of the stack with a tarp to protect the wood from rain and snow.

Cord Volume Calculations:

A standard cord of firewood measures 4 feet high, 4 feet wide, and 8 feet long, for a total volume of 128 cubic feet.
A face cord (also known as a rick or a stove cord) is typically 4 feet high and 8 feet long, but the depth can vary. The volume of a face cord depends on the depth of the stack.

Data Points:

Properly seasoned firewood can have up to 50% more heat value than green firewood.
Firewood that is stacked in a sunny and well-ventilated location can dry in as little as 6 months.

Practical Tips:

Use a wood moisture meter to check the moisture content of your firewood before burning it.
Rotate your firewood stack regularly to ensure even drying.
Consider using a firewood processor to automate the splitting and stacking process.

Conclusion

Mastering these five pro woodcutting secrets will transform your experience with the MS 391 Stihl chainsaw, enhancing both your efficiency and safety. Remember, wood processing is a blend of skill, knowledge, and respect for the tools and materials involved. By understanding the nuances of chainsaw calibration, wood selection, felling techniques, chain sharpening, and firewood preparation, you’ll not only become a more proficient woodcutter but also deepen your connection with the natural world. Now, get out there, stay safe, and enjoy the satisfying rhythm of turning trees into warmth and comfort!

MS 391 Stihl Chainsaw Tips (5 Pro Woodcutting Secrets)