How To Change String on Brush Cutter

Maintaining your brush cutter's efficiency often involves replacing the cutting string or line. Over time, the string wears out from cutting through thick vegetation, requiring periodic replacement to keep your tool functioning optimally. This article provides a comprehensive guide on how to change the string on a brush cutter, covering the necessary tools, steps, and safety precautions to make the process easy and safe.

So, how do you change the string on a brush cutter? 

The process involves preparing the string, removing the trimmer head, winding the new string, and reassembling the trimmer head. Below, we’ll go into detail on each of these steps to ensure you change your brush cutter string efficiently and effectively.

Preparing the New String

Before starting the replacement process, gather the necessary materials and prepare the new string.

1. Choosing the Right String: Select the appropriate diameter and type of string recommended by your brush cutter’s manufacturer. The size typically varies between 0.065 inches (1.65 mm) and 0.095 inches (2.41 mm). Thicker strings are more durable for tough vegetation but ensure compatibility with your model.

2. Cutting the String: Measure and cut the required length of new string. Most brush cutter heads require between 10 to 25 feet of string, but refer to the user manual for the exact length. Cut two equal pieces if your trimmer head uses a dual-line mechanism.

3. Cleaning the String and Head: Ensure that the new string is clean and free from dirt or debris. Wipe down the trimmer head to remove any grass clippings or dirt buildup that might interfere with the installation.

Removing the Trimmer Head

To replace the string, you first need to access the spool inside the trimmer head.

1. Turn Off and Disconnect: Ensure the brush cutter is completely turned off. For gas-powered models, disconnect the spark plug to prevent accidental starts. For electric models, unplug the power cord or disconnect the battery.

2. Positioning the Brush Cutter: Lay the brush cutter on a flat surface with the head facing up. Stabilize the tool to prevent it from moving while you work on it.

3. Opening the Trimmer Head: Locate the trimmer head, which houses the spool. The method to open it may vary depending on the model. Common methods include:

• Depressing Tabs: On some models, there are tabs on either side of the head that need to be depressed simultaneously to release the housing.

• Screws: Other models may have screws that need to be removed with a screwdriver.

• Twist-off Cap: Some trimmer heads have a cap that twists off counterclockwise.

4. Remove the Spool: Once the trimmer head is open, carefully remove the spool from the housing. Pay attention to how the existing string is wound to help guide the placement of the new string.

Winding the New String

Properly winding the new string ensures optimal performance and minimizes issues during operation.

1. Locating Wind Direction: Most spools have arrows indicating the direction to wind the string. Follow the arrows to ensure correct winding.

2. Inserting the String: Insert one end of the string into the hole or notch on the spool. Pull it through until you have about six inches of string protruding from the notch.

3. Winding the String: Wind the string around the spool in the indicated direction, keeping the tension even. Avoid overlapping the string as it can cause jams. For dual-line heads, wind each string on its respective side of the spool, ensuring they are kept separate.

4. Securing the Ends: Once the string is fully wound, secure the ends in the notches or slots on the spool to keep them from unwinding.

Reassembling the Trimmer Head

After winding the new string, reassemble the trimmer head and prepare for use.

1. Replacing the Spool: Place the wound spool back into the trimmer head housing. Ensure it sits securely and that the string ends extend through the eyelets or holes in the housing.

2. Aligning and Securing: Align the housing cover with the base and secure it by either pressing the tabs back into place, tightening the screws, or twisting the cap clockwise until it’s firmly attached.

3. Adjusting the String Length: Pull the string ends to ensure they are of equal length. If necessary, use a pair of scissors to trim the ends to the manufacturer’s recommended length.

4. Testing: Before starting the brush cutter, manually pull the string to ensure it moves freely through the eyelets without resistance or tangling.

Performing a Safety Check

Before using your brush cutter with the new string, conduct a safety check to ensure everything is properly installed and functioning.

1. Reconnect Power: Reconnect the spark plug for gas models or plug in the power cord/battery for electric models.

2. Initial Run: Turn on the brush cutter and run it at low speed initially to check for any unusual noises or vibrations. Observe how the string operates to ensure it feeds correctly.

3. Cutting Test: Test the brush cutter on a small patch of vegetation to confirm the string is cutting efficiently and there are no operational issues.