How to Measure Chainsaw Bar Length: A Comprehensive Guide
Choosing the right chainsaw bar length is crucial for efficient and safe operation. A bar that’s too long can be unwieldy and potentially dangerous, while one that’s too short might limit your cutting capacity. This comprehensive guide will walk you through the process of accurately measuring your chainsaw bar length, ensuring you select the appropriate size for your needs. We’ll cover everything from understanding bar length terminology to providing step-by-step instructions and answering frequently asked questions.
Why is Chainsaw Bar Length Important?
The chainsaw bar length, also known as the guide bar length, is the length of the cutting portion of the bar, not the entire bar length. It directly impacts several aspects of your chainsaw’s performance and your safety:
* **Cutting Capacity:** A longer bar allows you to cut larger diameter logs and trees. However, it also requires more power from the chainsaw engine. Overburdening the engine with a bar that’s too long can lead to overheating and premature wear.
* **Maneuverability:** Shorter bars are generally easier to maneuver, especially in tight spaces or when felling smaller trees and pruning. Longer bars can be more cumbersome, requiring greater physical strength and control.
* **Safety:** An improperly sized bar can increase the risk of kickback, a dangerous phenomenon where the chainsaw suddenly thrusts backward. A bar that’s too long for the engine can also lead to instability and loss of control.
* **Chain Speed & Performance:** A bar that’s too long can reduce the chain speed, reducing the chainsaw’s cutting performance. An adequately sized bar will allow for optimal cutting speed and efficiency.
Understanding Chainsaw Bar Terminology
Before we dive into the measurement process, let’s define some key terms:
* **Bar Length (Guide Bar Length):** As mentioned earlier, this refers to the usable cutting length of the bar. It’s the distance from the tip of the bar to where it enters the chainsaw housing.
* **Overall Bar Length:** This is the total length of the bar, including the portion that fits inside the chainsaw housing. This measurement is generally not used for matching bar sizes.
* **Gauge:** The gauge refers to the thickness of the drive links on the chainsaw chain, which must match the width of the groove in the guide bar. Mismatched gauges can cause the chain to bind or come off the bar.
* **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 the bar and sprocket.
* **Drive Links:** These are the small metal pieces on the chain that fit into the groove of the guide bar and are propelled by the chainsaw’s sprocket.
Where to Find the Existing Bar Length Information
Your chainsaw’s current bar length is usually found in one of several places. Locating it here, if possible, can be an easy way to reference the existing bar length rather than manually measuring.
* **Sticker on the Bar:** Many chainsaw bars have a sticker or printed label indicating the bar length, gauge, and pitch. This is usually the easiest place to find the information.
* **Operator’s Manual:** The chainsaw’s operator’s manual will specify the recommended bar length range for that particular model. Consult your manual before making any changes.
* **Stamped on the Bar:** Some bars have the bar length stamped directly onto the metal. Look closely near the base of the bar where it connects to the chainsaw body.
Tools You’ll Need to Measure Chainsaw Bar Length
To accurately measure your chainsaw bar length, you’ll need the following tools:
* **Measuring Tape or Ruler:** A standard measuring tape or ruler with clear markings.
* **Gloves:** To protect your hands from sharp edges and debris.
* **Pencil and Paper (Optional):** To record the measurement for future reference.
Step-by-Step Instructions for Measuring Chainsaw Bar Length
Follow these steps to measure your chainsaw bar length accurately:
**Step 1: Safety First**
Before you begin, ensure the chainsaw is turned off and the chain brake is engaged. If you’re removing the bar, disconnect the spark plug wire to prevent accidental starting. Wear gloves to protect your hands.
**Step 2: Locate the Measuring Point**
The starting point for measuring the bar length is where the bar exits the chainsaw housing. This is the point where the cutting portion of the bar begins. It is *not* the very back end of the bar, but where the bar extends from the saw body.
**Step 3: Extend the Measuring Tape**
Extend the measuring tape from the measuring point (where the bar exits the chainsaw housing) to the tip of the bar. Make sure the tape measure follows the straight line of the bar. Don’t measure along the curve of the bar.
**Step 4: Read the Measurement**
Carefully read the measurement on the measuring tape. The measurement should be in inches or centimeters. This is the effective cutting length of your chainsaw bar.
**Step 5: Record the Measurement (Optional)**
Write down the measurement on a piece of paper or in your phone for future reference. This will be helpful when purchasing a replacement bar or chain.
**Step 6: Verify the Measurement (Important!)**
To ensure accuracy, repeat the measurement a second time. If the two measurements are the same, you can be confident in your result. If they differ slightly, take a third measurement and use the average of the three.
**Example:** Let’s say you measure from where the bar leaves the chainsaw body to the tip of the bar, and it reads 18 inches. This means you have an 18-inch chainsaw bar.
Measuring a Chainsaw Bar That Has Been Removed
If you have removed the chainsaw bar, the process is slightly different but just as straightforward.
**Step 1: Lay the Bar Flat**
Place the chainsaw bar on a flat surface, such as a workbench or table.
**Step 2: Locate the Measuring Point**
The measuring point is still the point where the bar emerges from the chainsaw body when installed. You can usually identify this point by looking for the mounting holes or the area where the bar widens to fit inside the chainsaw.
**Step 3: Extend the Measuring Tape**
Extend the measuring tape from the measuring point to the tip of the bar, ensuring it follows a straight line.
**Step 4: Read and Record the Measurement**
Read the measurement on the measuring tape and record it for future use.
**Step 5: Verify the Measurement**
As before, repeat the measurement to ensure accuracy.
What if My Measurement Falls Between Standard Sizes?
Chainsaw bars come in standard sizes, typically increasing in increments of 2 inches (e.g., 16 inches, 18 inches, 20 inches). If your measurement falls between two standard sizes, it’s generally best to round *down* to the smaller size. For instance, if you measure 17 inches, you’d likely choose a 16-inch bar. This is because using a bar that’s too long for your chainsaw’s engine can negatively affect performance and safety.
Matching the Chain to the Bar
Once you know the bar length, you’ll need to ensure you purchase the correct chainsaw chain. The chain length is determined by the bar length, gauge, and pitch. The easiest way to ensure a proper match is to refer to your chainsaw’s operator’s manual or the existing chain’s specifications. You can also consult with a knowledgeable salesperson at a chainsaw supply store. When purchasing a chain, you’ll need to know:
* **Bar Length:** The length you just measured.
* **Gauge:** The thickness of the drive links (usually expressed in thousandths of an inch, e.g., .050″, .058″, .063″).
* **Pitch:** The distance between the chain’s rivets (usually expressed in inches, e.g., 3/8″, .325″, .404″).
* **Drive Link Count:** The number of drive links on the chain. This is crucial for ensuring the chain fits properly on the bar.
Common Mistakes to Avoid When Measuring Chainsaw Bar Length
* **Measuring the Entire Bar Length:** Remember to measure only the cutting length, from where the bar exits the chainsaw housing to the tip.
* **Measuring Along the Curve:** Ensure the measuring tape follows a straight line along the bar.
* **Ignoring the Gauge and Pitch:** Bar length is only one part of the equation. You must also match the gauge and pitch of the chain to the bar.
* **Choosing a Bar That’s Too Long:** It’s generally better to err on the side of a shorter bar than one that’s too long.
* **Assuming All Chainsaws Use the Same Bar:** Each chainsaw model has specific bar length recommendations. Always consult your operator’s manual.
Tips for Choosing the Right Chainsaw Bar Length
* **Consider the Type of Work:** For felling large trees, a longer bar is generally preferred. For pruning and limbing, a shorter bar is more maneuverable.
* **Match the Bar to the Engine Power:** A more powerful chainsaw can handle a longer bar. Consult your operator’s manual for recommended bar lengths.
* **Think About Your Experience Level:** Beginners may find it easier to control a chainsaw with a shorter bar.
* **Consult with Experts:** If you’re unsure, seek advice from experienced chainsaw users or professionals at a chainsaw supply store.
* **Check Your Chainsaw’s Manual:** This is the most reliable source for information on recommended bar lengths for your specific chainsaw model.
Maintaining Your Chainsaw Bar
Proper maintenance can extend the life of your chainsaw bar and ensure optimal performance. Here are some tips:
* **Regularly Clean the Bar:** Remove sawdust and debris from the bar groove using a bar groove cleaner or a flat screwdriver.
* **Lubricate the Bar:** Use chainsaw bar and chain oil to keep the bar and chain properly lubricated. Insufficient lubrication can lead to overheating and premature wear.
* **Check for Wear and Damage:** Inspect the bar for signs of wear, such as burrs, cracks, or uneven rails. If you find any damage, replace the bar immediately.
* **File the Bar Rails:** Use a bar rail dresser to keep the bar rails square and even. This will help ensure smooth and accurate cuts.
* **Rotate the Bar:** Periodically rotate the bar to distribute wear evenly.
* **Store the Chainsaw Properly:** Store the chainsaw in a dry place, away from direct sunlight and extreme temperatures.
Conclusion
Measuring your chainsaw bar length accurately is a simple but essential task for maintaining your chainsaw and ensuring safe and efficient operation. By following the steps outlined in this guide, you can confidently determine the correct bar length for your needs and select the appropriate chain. Remember to prioritize safety, consult your operator’s manual, and seek expert advice when needed. Proper bar and chain selection will improve your chainsaw’s performance, extend its lifespan, and make your cutting tasks easier and more enjoyable.
Frequently Asked Questions (FAQs)
**Q: What happens if I use a bar that’s too long for my chainsaw?**
A: Using a bar that’s too long can strain the chainsaw’s engine, reduce chain speed, increase the risk of kickback, and make the chainsaw more difficult to control. It can also lead to premature wear and damage to the engine and bar.
**Q: Can I use a shorter bar than what’s recommended in my chainsaw’s manual?**
A: Yes, in most cases, you can use a shorter bar than the maximum recommended length. A shorter bar will make the chainsaw more maneuverable and easier to control, especially for smaller tasks like pruning.
**Q: How often should I replace my chainsaw bar?**
A: The lifespan of a chainsaw bar depends on several factors, including the frequency of use, the type of wood being cut, and the quality of maintenance. Inspect the bar regularly for signs of wear and damage, and replace it when necessary.
**Q: Can I sharpen my chainsaw chain myself?**
A: Yes, you can sharpen your chainsaw chain yourself using a file and a chain sharpening guide. However, it’s important to learn the proper technique to avoid damaging the chain. Alternatively, you can have your chain sharpened professionally.
**Q: Where can I buy chainsaw bars and chains?**
A: You can purchase chainsaw bars and chains at chainsaw supply stores, hardware stores, and online retailers. Be sure to choose a reputable supplier that offers high-quality products.
By understanding these aspects of chainsaw bar measurement and maintenance, you’ll be well-equipped to handle your chainsaw safely and effectively for years to come.