How To Replace a Strimmer Line Strimmers (or grass trimmers) are garden-essential tools. They make light work of overgrown grass patches, and give a tidy edge to lawn areas that are hard to reach with a mower. Like all tools with moving parts, they sometimes need a little maintenance. One such task that any gardener should know how to do is how to replace a strimmer line. In this article we’ll tell you how, step by step. Whether your strimmer line has broken, or it’s just naturally worn down to nothing after a lot of use, we’re here to tell you everything you need to know about how to replace a strimmer line, simply, safely, and as quickly as possible. Why Do Strimmer Lines Need Replacing? Strimmer lines will naturally wear down over time with normal use. Each time the nylon string whips around and makes contact with grass, weeds, or harder surfaces like fencing, walls, or paving slabs, it will slowly erode. After enough uses, the line will become too short or completely break, rendering it unable to cut effectively. When this happens, you’ll need to either feed more line from the spool, or if it’s empty, attach a new one. Let’s have a look at how to do this. Step-by-Step: How to Replace a Strimmer Line Step 1: Check the Type of Strimmer Head You Have The two main types of strimmer heads are: Single line: Only one cutting line feeds from the spool. Dual line: Two lines are extended from the head at once, offering more powerful cutting. Replacement is similar in both cases, but the first step is to confirm which you have. Tip: Refer to your user manual, or look closely at the head of the strimmer itself. Most will have a diagram stamped into the plastic showing the direction of the line feed, and whether single or dual line. Step 2: Prepare Tools and Safety Gear Gather the following in preparation for the task: Correct replacement strimmer line (check diameter in user manual, typically 1.3mm to 2.4mm). Scissors or garden shears. Protective gloves Safety goggles (optional if working with dusty or overgrown equipment). Disconnect the power source: For corded strimmers: unplug from the mains. Battery operated models: remove the battery. Petrol models: turn off, and wait for engine to cool. Step 3: Remove the Spool Cover Turn the strimmer upside down, and locate the spool cover on the cutting head. It may: Click off with light pressure. Unscrew Remove the spool cover carefully and note how it’s fitted. It will need to be reattached in the same way. Step 4: Remove the Spool and Any Existing Line Extract the spool (the circular part inside the head) from the housing. If there’s any line left, remove this. Check the spool and housing for any built-up dirt or grass. Clean this out with a dry cloth or brush if necessary. Step 5: Cut and Wind the Replacement Line The next step is the most important part of the process, winding the replacement line. Cut the line: Measure and cut approximately 3–5 metres of replacement line (see your model’s specifications). For dual line heads, cut two equal lengths. Locate the starter holes: On the spool, you’ll notice one (or two, for dual-line heads) small holes. Insert about 0.5 cm of line into each hole to anchor it in place. Wind the line: Wrap the line around the spool in the direction indicated. (Typically this will be marked with an arrow.) Keep it tight and even to prevent tangles. Leave around 15 cm of line free at the end. Secure the ends: Some spools have notches that can hold the line in place temporarily. Use these to keep things tidy while you reassemble. Step 6: Replace the Spool and Cover Feed the ends of the line through the eyelets in the strimmer head. Insert the spool back into the housing. Gently pull on the line ends to ensure they’re moving freely. Replace the spool cover, either by snapping it back in place or twisting it on. When everything is back in place and secure, you’re almost ready to start again. Step 7: Give It a Test Plug your strimmer’s power source back in. (Or replace the battery.) Hold it away from any surfaces and switch it on for a second. The lines should extend a little and spin freely. If your strimmer is bump feed type, tapping the base of the strimmer head on the ground will feed more line out automatically as it wears down. For manual feed models, you may need to open the head and release more line manually. Common Mistakes to Avoid Using the wrong line thickness: Too thin and it will wear very fast, too thick and it may jam the spool or feeder mechanism. Winding the line the wrong way: Line must be wound in the indicated direction. If not, it will jam the head or snap frequently. Overfilling the spool: It will either jam the head or stop the line from feeding smoothly. Neglecting to clean the spool housing: Grass and dirt can build up and create friction or affect performance. When to Replace the Entire Strimmer Head In some cases, especially for budget or older strimmers, it can be easier to simply replace the entire strimmer head. This may be the case where the spool tends to jam frequently, or where the spring mechanism is worn. There are several universal strimmer head replacements on the market that will last a long time. Remember to double check you’re buying the right type of replacement (single or dual line). Final Thoughts Replacing a strimmer line can seem daunting the first time you do it. But it’s a quick and simple job once you’ve got the hang of it. Regular maintenance will not only prolong the life of your tool, but also give you a professional looking finish to your garden edges and borders. Now that you know how to replace a strimmer line correctly, it’s easy to see why it’s worth doing yourself. Happy trimming! Need advice on the right replacement line, or strimmer parts? Mowshop stocks strimmer accessories and replacement parts for all the major brands — with fast delivery and expert advice, available just a click away.
