To change strimmer line, first identify your trimmer head type: bump-feed spool, fixed-line, or easy-load. For bump-feed spools, remove the spool, cut away old line, thread new line through the eyelet, and wind it in the specified direction. For fixed-line heads, cut new line to the required length and insert it into the designated slots. Always use the manufacturer-recommended line diameter and material for your specific model.
Replacing your trimmer line is a fundamental maintenance task for any gardener. Whether you are dealing with a worn-down bump-feed spool or a snapped piece of fixed line, knowing the correct procedure prevents damage to the trimmer head and ensures your equipment operates efficiently. Because different brands and models utilize vastly different mechanisms, a “one size fits all” approach can lead to jammed heads or broken components. This guide breaks down the process by head type to ensure a successful restringing every time.
Understanding Your Trimmer Head Type
Before you reach for your replacement line, you must determine how your string trimmer delivers line to the ground. Attempting to use a bump-feed method on a fixed-line head will result in frustration and potential damage to the device.
Common Types of Strimmer Heads
- Bump-Feed Spool: This is the most common mechanism. The user taps the head on the ground while the motor is running, which releases a small amount of line from an internal spool.
- Fixed-Line Head: These heads do not have a rotating spool. Instead, individual pieces of line are inserted directly into holes or slots in the head and secured manually.
- Easy-Load (or Automatic) Heads: These are designed for convenience, often allowing you to feed line through the head without fully disassembling the spool, sometimes using a specialized loading tool.
How to Identify Your Mechanism
Look at the bottom of the trimmer head. If you see a spring-loaded button or a cap that can be pressed down, it is likely a bump-feed system. If the head appears solid with small holes on the perimeter, it is likely a fixed-line system. If the head has a prominent eyelet or a specialized loading port, it may be an easy-load model.
Safety Note: Always consult your manufacturer’s instruction manual. If the head mechanism appears complex or if you are unsure of how to disassemble it, contact a qualified professional or the manufacturer to avoid damaging the internal spring or gear assembly.
How to Restring a Bump-Feed Spool Trimmer
The bump-feed system is popular because it allows for continuous use without stopping to manually adjust the line. However, it requires careful winding to function correctly.
Safely Removing the Old Spool and Line
- Power Down: Ensure the engine is off or the battery is removed. Never attempt to service a trimmer while it is powered.
- Access the Spool: Depending on your model, you may need to unscrew a central cap or press a release tab. Some heads require a small screwdriver or a coin to loosen the locking mechanism.
- Clear the Old Line: Once the spool is accessible, remove any remaining tangled or broken line. If the line is stuck, you may need to carefully cut it away with side cutters.
Threading and Winding New Line
Once the spool is clear, you are ready to reload. Accuracy during this stage is vital for the line to feed properly during use.
- Check the Winding Direction: Look for an arrow embossed on the spool or the trimmer head. This indicates the direction in which the line must be wound. Winding in the wrong direction will cause the line to unravel during operation.
- Thread the Eyelet: Locate the small hole (the eyelet) through which the line exits the head. Feed one end of your new trimmer line through this hole.
- Wind the Spool: Begin winding the line around the spool. It is essential to wind the line tightly and evenly. Gaps or overlapping loops can cause the line to jam or snap prematurely.
- Secure the Line: Once the spool is full, ensure the end of the line is tucked or secured according to the manufacturer’s design to prevent it from unspooling prematurely.
Reassembling the Trimmer Head
Place the spool back into the head assembly. Ensure it sits flush and that the spring mechanism (if present) is correctly positioned. Screw the cap back on firmly, but avoid over-tightening, which can crack plastic components. Test the bump mechanism by tapping the head lightly while the machine is off to ensure the cap moves freely.
How to Replace Line on a Fixed-Line or Easy-Load Trimmer Head
Fixed-line and easy-load systems are often found on smaller, lightweight trimmers or specialized professional models. They prioritize simplicity over the continuous feed of a bump-feed system.
Removing Old Line from a Fixed-Line Head
In a fixed-line system, the line is usually cut to a specific length and inserted into slots. To remove it, simply pull the old pieces out of the eyelets or slots. If the line has become embedded in the plastic, you may need to use pliers to extract the remnants.
Inserting New Line
- Measure the Length: Refer to your manual for the recommended line length. Using line that is too long can cause the motor to strain, while line that is too short will not reach the ground effectively.
- Insert into Slots: Push the ends of the line into the designated slots or eyelets. Some models require you to bend the line slightly to fit it through the aperture.
- Secure the Line: Some fixed-line heads use a locking mechanism or a small screw to hold the line in place. Ensure the line is firmly seated so it does not fly out during high-speed rotation.
Using Easy-Load Systems
Easy-load heads are designed to minimize disassembly. These often feature a large eyelet where you can feed the line through the head and then use a specialized tool or a specific twisting motion to wind the line onto the internal spool without removing the cap. Always follow the specific sequence provided by your manufacturer for these models, as the internal geometry is unique to each brand.
Key Factors for Selecting Replacement Trimmer Line
Not all trimmer lines are created equal. Selecting the wrong type can lead to frequent snapping, poor cutting performance, or even damage to your trimmer motor.
Line Diameter and Shape
The line diameter is one of the most critical specifications. Using a line that is too thick can jam the head, while a line that is too thin may snap instantly upon contact with grass. Common diameters vary by machine size, so always check your manual.
The shape of the line also affects performance:
- Round Line: The most common and versatile. It is durable and works well for general grass trimming.
- Square/Quadrilateral Line: These have sharper edges which can provide a cleaner cut in thicker vegetation.
- Star/Splitted Line: Designed to reduce air resistance and increase cutting efficiency by slicing through grass more easily.
Material Composition
Most trimmer lines are made from nylon, but different formulations offer different benefits:
- Standard Nylon: Flexible and cost-effective for light garden maintenance.
- Reinforced Nylon: Contains additives to increase stiffness and heat resistance, making it better for heavy-duty or professional use.
- Braided Line: Offers high durability and is less likely to snap when hitting hard surfaces, though it may require more torque from the motor.
Why Specifications Matter
Using the manufacturer-recommended line ensures that the centrifugal force generated by the spinning head is balanced. Using incorrect specifications can lead to uneven wear on the trimmer head, increased vibration, and potential safety hazards if the line breaks unexpectedly during high-speed operation.
