Running out of trimmer line mid-job is one of the most frustrating things about yard work. You're halfway through edging the driveway, and suddenly the string disappears into the head. Learning how to restring a weed trimmer head saves you a trip to the hardware store and keeps your weekend project on schedule.
The good news? Restringing is simpler than most people think. Once you understand the winding direction and how your specific head type works, the whole process takes about five minutes.
Safety first: Always disconnect the power source before working on your trimmer head. Unplug electric models, remove the battery from cordless units, and shut off the engine on gas trimmers. Wait for all moving parts to completely stop before touching the head.
Whether you're a first-time homeowner or a seasoned landscaper, this guide walks you through every step. We'll cover single and dual string heads, bump feed mechanisms, troubleshooting, and brand-specific tips. If you're also shopping for a new trimmer this season, check out these string trimmer deals for current savings.
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Gather your supplies before opening the trimmer head. Having everything ready makes the job go much faster and prevents mid-project interruptions.
Replacement trimmer line (check your manual for the correct diameter, typically 0.065 to 0.095 inches)
Scissors or a sharp utility knife for cutting line
A clean rag to wipe out debris from the head
Safety glasses to protect your eyes
Work gloves for grip and hand protection
Trimmer line comes in several shapes: round, square, star, and twisted. Round line lasts longest for heavy weeds. Square and star shapes cut more cleanly for regular lawn grass. Twisted line reduces noise and vibration, making it a solid all-around choice.
Follow these six steps to get your trimmer back in action. The process works for most major brands including STIHL, Husqvarna, Echo, Ryobi, and Black+Decker.
This is the most important step for your safety. For electric and battery-powered trimmers, remove the battery or unplug the cord. For gas-powered models, turn the engine switch to the off position and pull the spark plug boot.
Wait at least 30 seconds after shutting down a gas trimmer to make sure all internal parts have stopped moving. Never skip this step, even if you're in a hurry.
Most modern trimmer heads use a bump feed design with two release tabs on the sides. Squeeze both tabs firmly and lift the cover straight off. Some models use a twist-off cap that unscrews counterclockwise.
If the cover feels stuck, tap it gently with the handle of your screwdriver. Years of grass buildup can create a tight seal. Clean out any debris inside the head with your rag while you have it open.
For STIHL AutoCut heads, press the tabs on the side of the mowing head and pull the spool out. For Husqvarna T35 heads, twist the cover counterclockwise to release it. Check your user manual if you're unsure about the release mechanism.
Lift out the empty spool and remove any remaining old string. Clean the spool and the inside of the head housing. Dirt and grass clippings can interfere with the line feeding properly.
Cut a length of new trimmer line based on your head type. For most standard bump feed heads, 10 to 15 feet of line works well. Dual string heads need two separate lengths of 6 to 8 feet each.
Check your user manual for the exact length recommendation. Using too much line causes the spool to jam, while too little means you'll be restringing again soon.
This is where many people get confused. The method differs between single-string and dual-string heads.
For single-string heads: Find the small hole in the center of the spool. Insert one end of the line about an inch into this hole. Some spools have a notch or groove instead of a hole. Bend the line and hook it into the notch.
For dual-string heads with two holes: Look for two small anchor holes on the spool. Insert one end of your first line length into one hole, and one end of the second length into the other hole. Many dual-string heads also allow you to fold one long piece of line in half and feed both ends through the two holes simultaneously.
For dual-string heads with one hole: Fold your line in half with one side slightly longer than the other. Insert the folded loop into the center hole. This offset technique, shared by experienced users on lawn care forums, helps the two strings feed evenly instead of tangling.
This step causes more confusion than any other part of the process. Wind the string the wrong way and your trimmer will not feed line properly.
Look at your spool carefully. You should see arrow indicators molded into the plastic. These arrows show the correct winding direction. On most trimmer models, the string winds following the arrow, which typically points counterclockwise.
Wind the line snugly around the spool, following the arrow direction. Keep firm tension on the line as you wind to prevent loose coils that can tangle inside the head. Overlap each layer neatly beside the previous one rather than stacking on top.
Leave about 4 to 6 inches of line unwound at the end. You'll need this excess to feed through the exit holes in the head housing. Secure the loose ends in the small notch or "U" indent slots on the spool rim. These notches hold the string in place while you reassemble the head.
With the string secured in the notches, place the spool back into the head housing. Feed the loose ends of the line through the exit holes in the housing sides.
Release the string from the notch slots once the ends are threaded through the exit holes. Pull gently on both ends to make sure the line moves freely through the holes.
Snap the cover back onto the head or twist it clockwise to lock it in place. Give the spool a gentle tug to confirm everything is seated correctly. The head should rotate freely without catching.
Reconnect your power source and test the trimmer at low speed. Tap the bump head on grass (never on concrete) to verify the line feeds properly.
The winding direction is critical because your trimmer head feeds line through centrifugal force and the bump mechanism. When wound correctly, the pulling action during operation tightens the coil. When wound backward, the pulling action loosens the coil and the line can slip out entirely.
Here's a simple way to check: after winding, pull on the loose end of the string. If the coil tightens, you wound in the correct direction. If the coil loosens, unwind and start over in the opposite direction.
Most STIHL and Husqvarna heads wind following the arrow marked on the spool, which usually means counterclockwise. Echo and Ryobi models sometimes differ, so always check the arrow indicator on your specific spool. If no arrow is visible, look for directional text stamped into the spool rim.
One forum user shared a helpful tip: "Line up the arrows, feed the line through, rotate the head until it's all wound up and you're good to go. It takes about 30 seconds once you know the direction."
Understanding your head type makes restringing much easier. Here's how to tell them apart.
Single-string heads use one line and are common on lighter-duty and budget trimmers. They're simpler to restring since you only work with one line. The cutting width is narrower, making them best for light trimming around flower beds and walkways.
Dual-string heads use two lines that exit on opposite sides of the head. They cut a wider path and handle heavier weeds more effectively. Most professional and mid-range trimmers use dual string. The restringing process involves either two separate line pieces or one folded piece threaded through two anchor points.
Check your head housing: if you see two exit holes directly across from each other, you likely have a dual-string head. If there's only one exit hole, you have a single-string model.
Bump feed trimmers have a spring-loaded button on the bottom of the head. Tapping this button on the ground while the trimmer is running releases fresh line from the spool. This is the most common head type on consumer and prosumer trimmers.
Fixed head trimmers use pre-cut lengths of line that snap into individual holders. There's no spool to wind. You simply insert a pre-cut piece of line into each holder, and it stays in place by friction. Fixed heads work well for heavy-duty commercial use where durability matters more than convenience.
Automatic line advance heads detect when the line gets short and feed more without any bumping. These are convenient but can be more complex to restring. Some STIHL and Echo models use this system.
Even with careful restringing, problems can occur. Here are the most common issues and how to fix them.
If your string slides out of the head when you start trimming, the line isn't anchored properly. Make sure you've inserted enough line into the anchor hole or bent it securely into the notch. A common mistake is inserting only a tiny amount of line that slips free under tension.
Also check that you wound in the correct direction. Backward winding causes the centrifugal force to push the line out instead of keeping it coiled.
Frequent string breakage usually comes down to three causes. First, you may be using line that's too thin for your trimming conditions. Heavier weeds require thicker line (0.080 to 0.095 inch). Second, you might be trimming too close to hard surfaces like fences, rocks, or sidewalks that wear down the line. Third, old or brittle line snaps easily, so replace line that has been stored for over a year.
When the bump feed stops working, the spool is likely jammed. Disassemble the head, remove the spool, and clean out all grass and dirt. Rewind the line with proper tension and reassemble. If the spring inside the head has lost tension, you may need a replacement head.
Also check for welded line. When trimmer line gets hot from friction, adjacent layers can fuse together inside the spool. Unwind past the fused section and rewind with consistent tension.
If the cover won't snap back on, the line inside is probably too thick or overfilled. Open the head, remove some line from the spool, and try again. The spool should spin freely inside the housing with no resistance from excess line.
Keep a pre-wound replacement spool on hand. When your trimmer runs out of line mid-job, you can swap spools in under a minute and keep working. Rewind the empty spool later when you have time. This approach is popular among professional landscapers who can't afford downtime.
Soaking trimmer line in water is a widely repeated myth. Some claim it makes the line more flexible and less prone to breaking. In reality, modern nylon trimmer line performs identically whether soaked or dry. Save yourself the extra step.
Match your line diameter to your trimmer's power. Using line that's too thick on an underpowered trimmer bogs down the motor and causes poor cutting. Too-thin line on a powerful trimmer breaks constantly. Your user manual lists the recommended diameter range.
Store spare line in a cool, dry place away from direct sunlight. UV exposure degrades nylon over time, making it brittle. A sealed container in your garage or shed works well.
STIHL: AutoCut heads use a tap-and-go bump feed system. The spool has clear directional arrows and a winding channel that guides the line automatically. STIHL's EasySpool system on some models simplifies winding by reducing it to a matter of rotating the head.
Husqvarna: The T35 and T45 heads feature a simple tab release. Husqvarna heads typically use two separate line pieces for dual-string models. The winding direction is marked with raised arrows on the spool surface.
Echo: Echo Speed-Feed heads are designed for fast reloading. You can restring a Speed-Feed head in under a minute without disassembling the entire unit. Thread the line through the head, align the arrows, and rotate the bump knob to wind.
Ryobi and Black+Decker: These consumer-focused brands often use simpler single-string heads. The restringing process is straightforward, with clear anchor points and minimal disassembly required.
Most trimmer heads require you to wind the line following the arrow indicator molded into the spool, which typically points counterclockwise. If no arrow is visible, pull on the wound line after wrapping. If the coil tightens, you wound correctly. If it loosens, unwind and reverse the direction.
Remove the head cover, take out the empty spool, and clean out debris. Cut 10 to 15 feet of new line and insert one end into the anchor hole on the spool. Wind the line following the arrow direction with firm tension, leaving 4 to 6 inches unwound. Secure the ends in the notch slots, place the spool back in the housing, feed the line through the exit holes, and replace the cover.
To rethread a weed trimmer, first disconnect the power source. Open the head cover and remove the spool. Thread new line through the anchor hole or notch on the spool, wind it in the direction of the arrow indicator, and secure the loose end in a notch slot. Place the spool back in the housing, thread the line ends through the exit holes, and snap the cover closed.
No, restringing a weed eater is not difficult once you understand the winding direction for your specific head type. The entire process takes about five minutes. The most common mistake is winding the string in the wrong direction, so always check the arrow indicator on the spool before you start.
Weed eater string breaks quickly for three main reasons: the line diameter is too thin for the material you are cutting, you are trimming too close to hard surfaces like rocks and fences that wear down the line, or the line is old and brittle from extended storage. Use the correct line diameter for your trimmer, keep a safe distance from hard surfaces, and replace line older than one year.
Knowing how to restring a weed trimmer head is a skill every homeowner should master. The process comes down to six simple steps: disconnect power, remove the cover, prepare the line, insert it into the spool, wind in the correct direction, and reassemble.
The winding direction is the most common stumbling block. Always check the arrow indicator on your spool and test by pulling the line before closing the head. With a little practice, you'll have your trimmer back in action in under five minutes.
Restringing your own trimmer head saves money on replacement spools and professional service. Keep spare line on hand, store it properly, and your yard maintenance will never be interrupted by an empty spool again.