Why does my strimmer line keep breaking, and how do I reload it?
Why line snaps at the eyelet, choosing the right diameter and shape, and the winding method that stops it welding together in the spool.
- Difficulty
- beginner
- Time
- 30 min
- Read
- 5 min
- Safety
- warning
Short answer
Line breaks because it is too thin for the job, has gone brittle from being stored dry, or is being run into hard objects at the wrong angle. Soak old line in water for a day to soften it, use the diameter the machine specifies, and wind it neatly under tension in the direction of the arrows on the spool.
Nylon line is a consumable and it is meant to wear. What is not normal is line that snaps off at the eyelet within seconds every time, and that has a small number of causes — the wrong line, brittle line, a damaged eyelet, or a technique problem.
Safety
What you'll need
- Replacement line of the correct diameter
- A bowl of water (optional)
- Scissors (optional)
Step by step
- Check the line diameter against the machine.It is printed on the head or in the handbook, typically 1.6mm to 2.4mm for a domestic machine. Too thin and it snaps constantly; too thick and it will not feed, overloads the motor and can jam the head.
- Check whether the line has gone brittle.Nylon absorbs and loses moisture. Line that has sat in a dry shed for a year snaps like dry spaghetti. Soak a new spool in water for 24 hours before winding it and store it in a sealed bag with a damp cloth — this single habit fixes most breakage complaints.
- Look at the eyelet where the line exits.The line runs through a small guide in the head. Once that guide is worn into a notch it acts like a blade and cuts the line every time. Many heads have replaceable eyelets; a badly worn head needs replacing.
- Look at what you are cutting.Line cuts grass and soft weeds. Fed into a wall, a fence post, a wire fence, gravel or a kerb it will break every pass. Approach hard edges with the tip of the line only, and take a little at a time.
- Use the tip, not the middle.The tip is moving fastest and cuts best. Burying half the line length in thick growth loads the motor, overheats the head and breaks line. Work in shallow passes from the top down.
- Consider a different line shape for tougher work.Round line is the standard and lasts longest. Square, twisted and star-shaped lines cut more aggressively through thicker material and wear faster. Match it to what you actually cut.
- Open the head correctly to reload.Usually two tabs squeezed on the cap, or a threaded knob. Note how the spool sits before lifting it out and take a photo — the spring underneath is easy to lose and the assembly only goes back one way.
- Cut the right length and follow the arrows.The head or the spool is marked with the maximum length and the winding direction. Winding against the arrow means the line will not feed. Too much line jams the head.
- Wind it tightly and neatly, keeping tension.Loose, crossed line binds inside the spool and will not feed — and at working temperature it can weld to itself. For a twin-line head, keep the two lines in their own channels and do not let them cross.
- Park the ends in the retaining notches.Most spools have small slots to hold the ends while you refit the cap. Feed each end out through its eyelet, then release from the notches once the cap is on.
- Test the feed before starting work.Bump the head on the ground with the machine running to check it advances. If it does not, the spool is wound too tightly, crossed, or has been fitted the wrong way up.
Tips
- Buy line by the reel rather than in pre-loaded spools. It is far cheaper and you can choose the diameter.
- Keep the spare reel in a sealed bag with a damp sponge. Line stored damp lasts far longer.
- A pre-wound spool that you swap in takes seconds. Keeping a loaded spare is the easiest upgrade to a strimming session.
Common mistakes
- Winding the line loosely or letting it cross — Loose coils bind inside the spool, so the automatic feed cannot pull line out. Under working heat, crossed line can also fuse together, which means dismantling the head to free it.
- Using the whole length of line against hard edges — The middle of the line is slower, does less cutting and takes more load. Driving it into a wall or a post breaks line and overloads the motor; use the last few centimetres of the tip.
If it doesn't work
Line snaps within seconds of starting
Cause: Brittle line, or a worn eyelet cutting it — Fix: Soak or replace the line and inspect the exit eyelet for a groove; replace the eyelet or the head.
Line will not feed when bumped
Cause: Wound too tight, crossed, or against the arrow — Fix: Rewind neatly in the marked direction with even tension.
Both lines come out together in a tangle
Cause: Twin lines crossed between channels — Fix: Rewind keeping each line strictly in its own channel.
Machine bogs down in long grass
Cause: Too much line out, or cutting too deep — Fix: Work top-down in shallow passes with the tip of the line.
Line welded solid inside the spool
Cause: Overheating from binding — Fix: Dismantle, discard that line, and rewind more loosely spaced but under even tension.
Questions people ask
Does soaking the line really help?
Yes, and it is well established. Nylon becomes brittle as it dries out, and dry line shatters rather than wearing. Twenty-four hours in water restores much of its flexibility, and storing it sealed with some moisture keeps it that way.
Can I use a metal blade instead?
Only if the machine is specifically designed and guarded for one, and even then it is a much more dangerous tool that can kick back hard. Do not fit a blade or any home-made cutting head to a machine sold for line.