Installing the correct size of guide bar and chain on your chainsaw is crucial for optimal performance. Incorrect sizes can lead to damage, not only to the chainsaw itself but also to the user. Therefore, when replacing either a chainsaw bar or chain, accurate measurement is key. This guide provides a detailed overview of how to measure a chainsaw guide bar, ensuring safety and efficiency in your chainsaw operations.
Understanding Chainsaw Bar Measurements
When you buy a chainsaw, the product description typically lists the chainsaw bar length, such as 16″, 18″, or 25″. If this information is readily available, simply purchasing a replacement bar of the same length should suffice. The chainsaw’s manual will also specify suitable bar lengths for your model. For popular models like Husqvarna or STIHL, you can usually find this information online if needed. However, if direct measurement is necessary, there are two primary measurements to consider: the cutting length and the true length.
Measuring the Cutting Length of a Chainsaw Bar
The cutting length refers to the distance from the tip of the bar to where it meets the chainsaw body. This measurement is straightforward and can be done using a tape measure without disassembling the chainsaw.
Since chainsaw bars are sold in standard sizes, always round up your measurement to the nearest available size to ensure a proper fit. This method is ideal for a quick estimate without requiring any tools beyond a tape measure.
Determining the True Length of a Chainsaw Guide Bar
For a more precise measurement, you’ll need to determine the true bar length. This involves removing the chainsaw bar from the chainsaw body. The method for doing so may vary depending on your chainsaw model.
- Loosen the Bolts: First, loosen the bolts that secure the chainsaw bar to the body. Refer to your owner’s manual for the exact location and procedure.
- Remove the Bar: Carefully remove the chainsaw bar from the chainsaw.
- Measure: Once removed, lay the chainsaw bar on a flat surface. Use a tape measure to measure the bar from end to end. This will provide the true length of your chainsaw bar.
This method offers the most accurate measurement, ensuring you select the correct replacement chainsaw guide bar.
Choosing the Right Replacement Chainsaw Bar
Besides size, consider the type of chainsaw bar you need:
- Solid Chainsaw Bars: Constructed from a single piece of steel, these bars are robust but less flexible.
- Laminated Chainsaw Bars: Lighter and more flexible due to their layered construction. However, they are not as strong as solid bars.
- Solid Replaceable Sprocket Nose Bars: These bars have a riveted tip with a sprocket for the chain. The nose can be replaced if damaged, extending the bar’s lifespan.
Measuring a Chainsaw Chain
Chainsaw chains are defined by three main measurements: pitch, gauge, and the number of drive links.
- Pitch: The distance between three rivets on the chain, divided by two.
- Gauge: The width of the drive links, which connect the chain to the bar.
- Drive Links: The number of these links determines the chain’s overall length and compatibility with your chainsaw.
Ideally, check the side of your chainsaw bar for a stamp indicating the chain size needed. This stamp typically includes the pitch (in inches, e.g., 1/4″), the number of drive links (followed by “DL” or a drive link symbol), and the bar gauge (in inches and mm, sometimes with a bar groove symbol).
If the stamp is unreadable, measure the chain yourself after removing it. To do this, first remove the bar and then use a screwdriver to release the chain tension.
Measuring Chainsaw Chain Pitch
Measure the distance between three rivets on the chain laid flat. Divide that measurement by two to obtain the pitch.
Measuring Chainsaw Chain Gauge
Using a tape measure for this can be inaccurate. Instead, use a dial caliper to precisely measure the thickness of a drive link. This will provide the accurate bar gauge measurement.
Counting Chainsaw Chain Drive Links
Wear safety gloves. Count the drive links on the chain. Marking the first link with tape or a marker can help you keep track and ensure an accurate count.
Conclusion
Accurately measuring your chainsaw guide bar and chain is essential for ensuring safety, performance, and longevity. Whether you’re determining the cutting length, true length, pitch, gauge, or drive link count, using the right methods and tools is key. By following this comprehensive guide, you can confidently select the correct replacement parts for your chainsaw.
