The best string trimmer for home use is the EGO Power+ ST1521S. This cordless model offers a combination of power, convenience, and efficiency, making it ideal for residential use. It features a 56-volt lithium-ion battery, providing ample power and a long runtime, which is essential for tackling various yard sizes without the hassle of cords or gas. The EGO Power+ ST1521S is equipped with a 15-inch cutting swath, allowing for efficient trimming of large areas. Its dual-feed spiral twist line ensures a clean and precise cut, reducing the time spent on yard work. The trimmer also includes a variable speed control, giving users the flexibility to adjust the power based on the task at hand, whether it's light trimming or tackling thicker weeds. One of the standout features of this model is its Powerload technology, which automatically winds the trimmer line, simplifying the often frustrating task of line replacement. Additionally, the trimmer's carbon fiber shaft is both lightweight and durable, reducing user fatigue and ensuring longevity. The EGO Power+ ST1521S is also praised for its quiet operation compared to gas-powered models, making it more suitable for residential areas where noise might be a concern. Its weather-resistant construction adds to its durability, allowing it to withstand various outdoor conditions. Overall, the EGO Power+ ST1521S offers a balance of power, ease of use, and innovative features, making it the best choice for homeowners seeking a reliable and efficient string trimmer for maintaining their lawns and gardens.

1. **Turn Off and Unplug**: Ensure the trimmer is turned off and unplugged or remove the battery for safety. 2. **Access the Spool**: Locate the trimmer head. Depending on the model, you may need to press tabs or unscrew a cap to access the spool. 3. **Remove the Spool**: Take out the spool from the trimmer head. Note the direction of the arrows indicating the winding direction. 4. **Prepare the New Line**: Cut a length of trimmer line, typically 10-25 feet, depending on the model. Check the manual for the correct diameter. 5. **Wind the Line**: Insert one end of the line into the anchor hole or slot on the spool. Wind the line tightly in the direction indicated by the arrows, ensuring the coils are neat and do not overlap. 6. **Secure the Line**: Once wound, secure the line by inserting the end into a notch on the spool to prevent unraveling. 7. **Replace the Spool**: Place the spool back into the trimmer head. Thread the line through the eyelets on the trimmer head. 8. **Reassemble the Trimmer Head**: Snap or screw the cap back onto the trimmer head, ensuring it is secure. 9. **Adjust Line Length**: Pull the line ends to ensure they are even and extend to the appropriate length. Trim any excess if necessary. 10. **Test the Trimmer**: Reconnect the power source and test the trimmer to ensure the line feeds correctly. Always refer to the specific model’s manual for detailed instructions and safety precautions.

A curved shaft string trimmer features a shaft that is bent, typically near the cutting head, which makes it shorter and more maneuverable. This design is generally lighter and easier to handle, making it ideal for trimming around small gardens, flower beds, and tight spaces. The curved shaft allows for a more ergonomic grip, reducing strain on the user's back and arms during operation. However, the shorter reach can be a limitation when trimming under bushes or in hard-to-reach areas. In contrast, a straight shaft string trimmer has a long, straight shaft that provides extended reach, making it suitable for larger areas and professional use. This design is better for trimming under obstacles like decks, shrubs, and fences. The straight shaft is typically more durable and can accommodate heavier-duty cutting heads, making it more versatile for different types of vegetation. However, it is usually heavier and may require more strength and effort to operate, which can lead to fatigue over extended periods. Overall, the choice between a curved and straight shaft string trimmer depends on the user's specific needs, the size of the area to be trimmed, and personal comfort preferences.

1. **Safety First**: Ensure the trimmer is turned off and unplugged or the battery is removed before maintenance. 2. **Cleaning the Trimmer Head**: Remove debris and grass clippings from the trimmer head using a brush or cloth. Check for any tangled grass or string and remove it. 3. **Inspect and Replace the Trimmer Line**: Check the trimmer line for wear and replace it if necessary. Follow the manufacturer's instructions for winding new line onto the spool. 4. **Check the Air Filter**: For gas trimmers, inspect the air filter. Clean it with soapy water if it's dirty, or replace it if it's damaged. 5. **Spark Plug Maintenance**: For gas models, inspect the spark plug. Clean it with a wire brush or replace it if it's worn out. 6. **Fuel System Care**: Use fresh fuel and add a fuel stabilizer if the trimmer will be stored for an extended period. Drain the fuel tank if storing for more than a month. 7. **Lubricate Moving Parts**: Apply lubricant to the trimmer's moving parts, such as the shaft and cutting head, to ensure smooth operation. 8. **Check the Guard and Handle**: Ensure the guard and handle are securely attached and free from damage. Tighten any loose screws or bolts. 9. **Battery Maintenance**: For battery-powered trimmers, keep the battery charged and store it in a cool, dry place. Avoid overcharging. 10. **Storage**: Store the trimmer in a dry, sheltered area. Hang it up if possible to prevent damage to the shaft. 11. **Regular Inspection**: Regularly inspect the trimmer for any signs of wear or damage and address issues promptly to prevent further problems.

The type of trimmer line you should use for your string trimmer depends on several factors, including the type of vegetation you are cutting, the power of your trimmer, and the specific model of your trimmer. Here are some guidelines: 1. **Material**: Most trimmer lines are made from nylon, but there are variations like reinforced nylon or copolymer blends for added durability. For heavy-duty tasks, consider lines with added materials like aluminum or other metals. 2. **Shape**: - **Round**: Best for general use and light trimming. It is durable and less likely to break. - **Square/Star**: Provides more cutting power and is suitable for thicker grass and weeds. - **Twisted**: Reduces noise and vibration, offering a cleaner cut. Ideal for professional use. - **Serrated**: Designed for heavy-duty tasks, such as thick weeds and brush. 3. **Diameter**: - **Light-duty (0.065" - 0.080")**: Suitable for small, residential lawns with light grass and weeds. - **Medium-duty (0.085" - 0.105")**: Good for thicker grass and moderate weeds. - **Heavy-duty (0.110" and above)**: Best for dense weeds, brush, and commercial use. 4. **Trimmer Compatibility**: Always check your trimmer’s manual for the recommended line size and type. Using the wrong line can damage the trimmer or reduce its efficiency. 5. **Environment**: Consider the noise level and environmental impact. Twisted lines are quieter, and some lines are biodegradable. Choose a trimmer line that matches your specific needs and the capabilities of your trimmer for optimal performance and longevity.

1. **Engine Won't Start**: - Check fuel: Ensure the tank has fresh, correct fuel mix. - Spark plug: Inspect for damage or fouling; clean or replace if necessary. - Air filter: Clean or replace if clogged. - Carburetor: Adjust or clean if fuel isn't reaching the engine. 2. **String Won't Feed**: - Spool: Ensure it's wound correctly and not tangled. - Bump head: Check for wear or damage; replace if necessary. - Line: Use the correct diameter and type for your model. 3. **Engine Runs Poorly**: - Fuel: Ensure it's fresh and mixed correctly. - Air filter: Clean or replace if dirty. - Spark arrestor: Clean if clogged. - Carburetor: Adjust settings or clean. 4. **Trimmer Line Breaks Easily**: - Line quality: Use high-quality, appropriate line. - Cutting technique: Avoid hitting hard surfaces. - Line size: Ensure correct diameter for your trimmer. 5. **Excessive Vibration**: - Loose parts: Tighten any loose screws or bolts. - Bent shaft: Inspect and replace if necessary. - Damaged head: Check for damage and replace if needed. 6. **Overheating**: - Air vents: Ensure they are clean and unobstructed. - Fuel mixture: Use the correct ratio to prevent engine strain. 7. **Smoke from Engine**: - Fuel mixture: Ensure correct oil-to-gas ratio. - Exhaust: Check for blockages. 8. **String Trimmer Head Won't Spin**: - Drive shaft: Inspect for damage. - Clutch: Check for wear or damage. 9. **Uneven Cutting**: - Line length: Ensure both sides are equal. - Cutting head: Inspect for damage or wear.

Gas and electric string trimmers each have their advantages and disadvantages, making them suitable for different needs and preferences. Gas string trimmers are typically more powerful, making them ideal for large yards or heavy-duty tasks like cutting through thick weeds and overgrown grass. They offer greater mobility since they are not tethered to a power source, allowing users to cover large areas without restriction. However, they are generally heavier, noisier, and require more maintenance, including fuel mixing and engine upkeep. They also emit fumes, which can be a concern for environmentally conscious users. Electric string trimmers come in two types: corded and cordless (battery-powered). Corded electric trimmers are lightweight, quieter, and require less maintenance than gas models. They are ideal for small to medium-sized yards with easy access to power outlets. However, their range is limited by the length of the extension cord, which can be cumbersome to manage. Cordless electric trimmers offer more mobility than corded models and are quieter and more environmentally friendly than gas trimmers. They are suitable for small to medium-sized yards but may not provide the same power and runtime as gas trimmers, depending on the battery capacity. Battery life and recharge time can be limiting factors, and replacement batteries can be costly. In summary, gas trimmers are better for large areas and tough jobs, while electric trimmers are more suitable for smaller yards and those prioritizing ease of use, low maintenance, and environmental concerns. The choice depends on the specific needs and preferences of the user.