066 Stihl Chainsaw Differences Explained (3 Pro Tips)

Imagine this: you’re standing in a forest, the scent of pine thick in the air. You’ve got a pile of downed oak trees that need processing, and your livelihood depends on getting the job done efficiently and effectively. The heart of your operation? A Stihl 066 chainsaw. But here’s the rub: you need to know this machine inside and out to truly master it.

Over the years, I’ve spent countless hours felling trees, bucking logs, and prepping firewood. I’ve wrestled with everything from stubborn hardwoods to tricky knots, and I’ve learned that understanding your chainsaw – especially a powerful beast like the Stihl 066 – is paramount. It’s not just about pulling the cord and making a cut; it’s about knowing its nuances, its strengths, and its potential pitfalls.

In this article, I’m going to break down the Stihl 066 chainsaw, highlighting key differences and offering three pro tips that can elevate your wood processing game. Whether you’re a seasoned logger or a weekend warrior tackling your firewood pile, this knowledge will help you work smarter, safer, and more productively. So, let’s dive in!

The Stihl 066: A Legend in the Woods

The Stihl 066, sometimes referred to as the MS 660 (its successor), is a chainsaw that commands respect. It’s a powerful, robust machine renowned for its reliability and cutting performance. However, understanding its variations and quirks is crucial to maximizing its potential.

066 vs. MS 660: What’s the Real Difference?

One of the first questions people often ask is, “What’s the difference between the Stihl 066 and the MS 660?” While they are often used interchangeably, there are some key distinctions. The MS 660 is essentially the updated version of the 066.

• Engine Design: While both share a similar engine displacement (around 91.6cc), the MS 660 incorporated some refinements in the cylinder design and combustion chamber for improved fuel efficiency and emissions.
• Carburetor: The MS 660 often features a slightly updated carburetor design compared to earlier 066 models.
• Anti-Vibration System: The anti-vibration system on the MS 660 may have minor improvements for reduced operator fatigue.
• Availability of Parts: Since the MS 660 is the newer model, parts availability is generally better compared to the older 066.

However, the core power and performance of both saws are very similar. Many parts are interchangeable, making them both highly desirable in the logging community.

Understanding the 066’s Strengths and Weaknesses

Like any tool, the Stihl 066 has its strengths and weaknesses.

Strengths:

• Raw Power: The 066 boasts incredible power, making it suitable for felling large trees and processing dense hardwoods.
• Durability: Built to withstand demanding conditions, the 066 is known for its robust construction and longevity.
• Versatility: With the right bar and chain, the 066 can handle a wide range of tasks, from felling to milling.
• Aftermarket Support: A vast aftermarket exists for the 066, offering a wide array of parts, modifications, and accessories.

Weaknesses:

• Weight: The 066 is a heavy saw, which can lead to fatigue during extended use.
• Fuel Consumption: Its powerful engine consumes a significant amount of fuel, especially when working under heavy loads.
• Vibration: While it has an anti-vibration system, the 066 can still transmit considerable vibration to the operator, especially compared to newer models.
• Cost: Finding a well-maintained 066 can be expensive, and replacement parts can also be pricey.

Wood Anatomy and Properties: Knowing Your Material

Before you even fire up your 066, understanding the wood you’re cutting is crucial. Wood isn’t just a homogenous material; it has a complex anatomy that affects its cutting characteristics, drying behavior, and fuel value.

Hardwood vs. Softwood: A Fundamental Distinction

The terms “hardwood” and “softwood” refer to the type of tree the wood comes from, not necessarily its actual hardness. Hardwoods are typically deciduous trees (they lose their leaves annually), while softwoods are typically coniferous trees (they have needles and cones).

• Hardwoods: Oak, maple, beech, and ash are examples of hardwoods. They generally have a higher density and are more difficult to cut than softwoods. They also tend to burn longer and hotter, making them ideal for firewood.
• Softwoods: Pine, fir, spruce, and cedar are examples of softwoods. They are generally less dense and easier to cut. They ignite more easily and burn quickly, making them suitable for kindling or starting fires.

Data Point: Oak, a common hardwood, has a density ranging from 0.60 to 0.90 g/cm³, while pine, a common softwood, has a density ranging from 0.35 to 0.50 g/cm³. This difference in density directly affects cutting resistance and fuel value.

Moisture Content: The Key to Efficient Cutting and Seasoning

Moisture content (MC) refers to the amount of water present in wood, expressed as a percentage of the wood’s oven-dry weight. MC significantly affects wood’s properties, including its weight, strength, and burning characteristics.

• Green Wood: Freshly cut wood has a high MC, often exceeding 50%. Green wood is heavier, more difficult to cut, and prone to warping and splitting during drying.
• Seasoned Wood: Seasoned wood has been dried to a lower MC, typically below 20%. Seasoned wood is lighter, easier to cut, and burns more efficiently.
• Kiln-Dried Wood: Kiln-dried wood has been dried in a controlled environment to a very low MC, typically below 10%. Kiln-dried wood is dimensionally stable and ideal for woodworking projects.

Data Point: The ideal MC for firewood is between 15% and 20%. Wood with a higher MC will be difficult to ignite, produce excessive smoke, and have a lower heat output.

My Experience: I once tried to burn freshly cut oak in my wood stove. It was a disaster! The fire struggled to stay lit, and the chimney produced so much creosote that I had to clean it much sooner than expected. That’s when I learned the importance of proper seasoning.

Grain Direction and Cutting Techniques

The grain direction of wood refers to the alignment of the wood fibers. Understanding grain direction is crucial for efficient cutting and preventing kickback.

• Cutting with the Grain: Cutting parallel to the grain is generally easier and produces a smoother cut.
• Cutting Against the Grain: Cutting perpendicular to the grain requires more power and can produce a rougher cut.
• Understanding Kickback: Kickback occurs when the chain catches on the wood, causing the saw to suddenly jump back towards the operator. Cutting with the tip of the bar, especially in dense knots or against the grain, significantly increases the risk of kickback.

Logging Tool Selection and Maintenance Best Practices

Your Stihl 066 is just one piece of the puzzle. Selecting the right bar and chain, along with proper maintenance, is crucial for safe and efficient operation.

Bar and Chain Selection: Matching the Tool to the Task

Choosing the right bar and chain for your 066 depends on the type of wood you’re cutting, the size of the trees you’re felling, and your personal preferences.

• Bar Length: Longer bars are suitable for felling large trees, while shorter bars are more maneuverable for bucking and limbing. A 20-inch to 25-inch bar is a good all-around choice for the 066.
• Chain Type:
  • Full Chisel: Full chisel chains have aggressive cutters that provide fast cutting speeds in clean wood. However, they are more prone to damage from dirt and debris.
  • Semi-Chisel: Semi-chisel chains have rounded cutters that are more durable and less prone to damage from dirt and debris. They are a good choice for general-purpose cutting.
  • Low-Profile: Low-profile chains have smaller cutters and are designed for safety and reduced kickback. They are a good choice for beginners or for cutting small trees and branches.
• Chain Pitch and Gauge: The pitch refers to the distance between the chain’s drive links, while the gauge refers to the thickness of the drive links. The 066 typically uses a .404″ pitch chain with a .063″ gauge.

Pro Tip: Consider using a ripping chain for milling lumber. Ripping chains have a specialized cutter geometry that produces smooth, accurate cuts parallel to the grain.

Sharpening Your Chain: The Key to Efficient Cutting

A sharp chain is essential for safe and efficient cutting. A dull chain requires more force, increases the risk of kickback, and puts unnecessary strain on the saw’s engine.

• Filing: Hand filing is a traditional method of sharpening chainsaw chains. It requires practice and precision but allows you to maintain the correct cutter angles and depth gauges.
• Electric Sharpeners: Electric sharpeners provide a faster and more consistent sharpening experience. However, they can be more expensive and may not be as precise as hand filing.
• Frequency: Sharpen your chain whenever it starts to feel dull or when you notice a decrease in cutting performance. I typically sharpen my chain after every few tanks of fuel.

My Experience: I used to neglect sharpening my chain, thinking it was a waste of time. But once I started sharpening regularly, I was amazed at the difference. My saw cut through wood like butter, and I was able to work much faster and with less effort.

Chainsaw Maintenance: Keeping Your 066 Running Smoothly

Regular maintenance is crucial for extending the life of your Stihl 066 and ensuring its reliable performance.

• Air Filter: Clean the air filter regularly to prevent dirt and debris from entering the engine. A clogged air filter can reduce engine power and increase fuel consumption.
• Fuel Filter: Replace the fuel filter annually to ensure a clean fuel supply to the carburetor.
• Spark Plug: Inspect and clean the spark plug regularly. Replace it annually or when it becomes fouled.
• Bar and Chain Oiler: Ensure the bar and chain oiler is functioning properly. A lack of lubrication can cause excessive wear and damage to the bar and chain.
• Chain Tension: Check the chain tension regularly and adjust as needed. A loose chain can derail and cause injury.
• Storage: Store your chainsaw in a dry, clean place when not in use. Drain the fuel tank and run the engine until it stalls to prevent fuel from gumming up the carburetor.

Firewood Seasoning Techniques and Safety Considerations

Properly seasoned firewood is essential for efficient burning and reducing creosote buildup in your chimney.

The Science of Seasoning: Understanding Moisture Loss

Seasoning firewood involves drying it to a lower MC, typically below 20%. This process allows the wood to burn more efficiently and produce more heat.

• Splitting: Splitting firewood increases its surface area, allowing it to dry more quickly.
• Stacking: Stack firewood in a single row, off the ground, with good air circulation. This allows air to flow around the wood, promoting evaporation.
• Sunlight: Expose firewood to direct sunlight to accelerate the drying process.
• Time: Allow firewood to season for at least six months, and preferably a year, before burning.

Data Point: Studies have shown that properly seasoned firewood can produce up to 50% more heat than green wood.

Seasoning Methods: From Simple to Sophisticated

There are several methods for seasoning firewood, ranging from simple air drying to more sophisticated kiln drying.

• Air Drying: Air drying is the most common method of seasoning firewood. It involves stacking the wood in a well-ventilated area and allowing it to dry naturally over time.
• Kiln Drying: Kiln drying involves drying the wood in a controlled environment, using heat and airflow to accelerate the drying process. Kiln-dried firewood is typically ready to burn in a matter of days or weeks.
• Solar Kilns: Solar kilns use solar energy to heat the air inside the kiln, providing a more sustainable and energy-efficient method of drying firewood.

Safety Considerations: Protecting Yourself and Others

Firewood preparation can be dangerous if proper safety precautions are not followed.

• Personal Protective Equipment (PPE): Always wear appropriate PPE, including safety glasses, hearing protection, gloves, and steel-toed boots.
• Chainsaw Safety: Follow all chainsaw safety guidelines, including proper starting procedures, cutting techniques, and kickback prevention.
• Splitting Safety: Use a splitting maul or hydraulic splitter with caution. Keep your hands and feet clear of the splitting area.
• Lifting Safety: Lift firewood with your legs, not your back. Avoid lifting heavy loads alone.
• Stacking Safety: Stack firewood securely to prevent it from collapsing.

Project Planning and Execution: Putting It All Together

Now that you have a solid understanding of the Stihl 066, wood properties, and safety considerations, let’s talk about project planning and execution.

Assessing Your Needs: What Are You Trying to Accomplish?

Before you start cutting, take some time to assess your needs and plan your project.

• What type of wood are you cutting?
• How much wood do you need?
• What is the intended use of the wood?
• What is your budget?
• What is your timeline?

Site Preparation: Setting the Stage for Success

Proper site preparation is essential for safe and efficient wood processing.

• Clear the area: Remove any obstacles, such as brush, rocks, and debris, from the cutting area.
• Establish a safe work zone: Mark off a safe work zone with cones or tape to prevent bystanders from entering the area.
• Plan your felling direction: Plan the direction in which you will fell trees to avoid hazards and ensure they fall in a safe location.
• Prepare a landing area: Prepare a landing area where you can buck and split the wood.

Felling Techniques: Bringing Down Trees Safely

Felling trees is a dangerous task that requires careful planning and execution.

• Assess the tree: Assess the tree for any defects, such as leaning, dead limbs, or rot.
• Plan your escape route: Plan an escape route that is clear of obstacles and will allow you to quickly move away from the falling tree.
• Make a notch: Make a notch on the side of the tree facing the direction you want it to fall. The notch should be about one-third of the tree’s diameter.
• Make a back cut: Make a back cut on the opposite side of the tree, slightly above the notch. Leave a hinge of wood to control the direction of the fall.
• Warn others: Warn others in the area before you start felling the tree.
• Watch the tree fall: Watch the tree fall and move away from the area quickly and safely.

Bucking and Splitting: Processing the Wood

Once the trees are felled, you can buck them into logs and split them into firewood.

• Bucking: Bucking involves cutting the logs into shorter lengths. Use a chainsaw to buck the logs, following proper safety precautions.
• Splitting: Splitting involves splitting the logs into firewood. Use a splitting maul or hydraulic splitter to split the logs.
• Stacking: Stack the firewood in a single row, off the ground, with good air circulation.

Three Pro Tips for Mastering the Stihl 066

Now, let’s get to the heart of the matter: three pro tips that will help you master the Stihl 066.

Pro Tip #1: Carburetor Tuning for Peak Performance

The Stihl 066 is a powerful machine, but it needs to be properly tuned to deliver its full potential. The carburetor controls the air-fuel mixture, and adjusting it correctly can significantly improve performance and fuel efficiency.

• Understanding the Adjustments: The carburetor has three main adjustment screws:
  • L (Low Speed): Controls the air-fuel mixture at idle and low speeds.
  • H (High Speed): Controls the air-fuel mixture at high speeds.
  • LA (Idle Speed): Controls the engine’s idle speed.
• Tuning Procedure:
  1. Warm Up the Engine: Start the engine and let it warm up for a few minutes.
  2. Adjust the Idle Speed: Turn the LA screw until the engine idles smoothly without stalling.
  3. Adjust the Low Speed: Turn the L screw until the engine accelerates smoothly from idle to full throttle. If the engine hesitates or stumbles, turn the L screw slightly richer (counterclockwise). If the engine bogs down or smokes, turn the L screw slightly leaner (clockwise).
  4. Adjust the High Speed: Make a test cut in a large log. Turn the H screw until the engine runs smoothly at full throttle without bogging down or smoking. If the engine bogs down, turn the H screw slightly richer (counterclockwise). If the engine smokes, turn the H screw slightly leaner (clockwise).

Caution: Over-leaning the carburetor can damage the engine. Always err on the side of caution and make small adjustments.

My Insight: I once spent hours struggling to cut through a large oak log with my 066. I was convinced that the saw was underpowered. But after carefully tuning the carburetor, the saw came alive. It was like a completely different machine!

Pro Tip #2: Mastering Felling Cuts for Directional Control

Felling trees safely and predictably requires mastering specific cutting techniques. The goal is to control the direction of the fall and minimize the risk of injury.

• The Hinge: The hinge is a strip of wood that remains uncut between the notch and the back cut. The hinge controls the direction of the fall.
• Open Face Felling: This technique involves creating a wider notch (70-90 degrees) and a shallower back cut. It is ideal for felling trees in open areas.
• Humboldt Cut: This technique involves creating a deeper notch and a more angled back cut. It is ideal for felling trees on slopes or in windy conditions.
• Boring Cut: This technique involves using the tip of the bar to bore through the tree, creating a hinge from the inside out. It is ideal for felling trees with a heavy lean.

Safety First: Always be aware of your surroundings and plan your escape route before making any cuts.

Case Study: I was once felling a large pine tree near a power line. The tree had a slight lean towards the power line, which made the situation very dangerous. I used a boring cut to create a hinge that would pull the tree away from the power line as it fell. The tree fell exactly where I wanted it to, avoiding the power line and preventing a potentially disastrous situation.

Pro Tip #3: Optimizing Chain Oiler Performance for Bar and Chain Longevity

Proper lubrication is essential for extending the life of your bar and chain. The chain oiler delivers oil to the bar and chain, reducing friction and preventing overheating.

• Checking the Oiler: Check the oiler regularly to ensure it is functioning properly. The chain should be visibly wet with oil when the saw is running.
• Adjusting the Oiler: Some Stihl 066 models have an adjustable oiler. Adjust the oiler to deliver more oil when cutting dense hardwoods or in hot weather.
• Cleaning the Oiler: Clean the oiler regularly to prevent it from becoming clogged with debris.
• Using the Right Oil: Use a high-quality bar and chain oil specifically designed for chainsaws. Avoid using motor oil or other substitutes, as they may not provide adequate lubrication.

Data Point: Studies have shown that proper lubrication can extend the life of a chainsaw bar and chain by up to 50%.

My Recommendation: I always use Stihl bar and chain oil in my 066. It’s a bit more expensive than some other brands, but it provides excellent lubrication and protection.

Conclusion: Mastering Your Stihl 066

The Stihl 066 is a powerful and versatile chainsaw that can handle a wide range of wood processing tasks. By understanding its nuances, mastering proper cutting techniques, and following these pro tips, you can unlock its full potential and work smarter, safer, and more efficiently. Remember to always prioritize safety, maintain your equipment, and respect the power of this legendary machine.

So, get out there, put these tips into practice, and experience the satisfaction of mastering your Stihl 066. The forest awaits!

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