Introduction
Learning how to wrap Stihl weed eater string is a fundamental skill for anyone who relies on a Stihl trimmer for lawn care, landscaping, or property maintenance. Properly wound line ensures clean cuts, reduces engine strain, and extends the life of both the cutting head and the trimmer itself. This guide covers the two most common Stihl cutting heads—FixCut and AutoCut—and provides detailed, step‑by‑step instructions for each. Whether you are a seasoned professional or a first‑time owner, the information below will help you reload line quickly, safely, and correctly.
- Understanding Stihl Trimmer Heads
- Tools and Materials Needed
- Preparing the Trimmer
- How to Wrap String on a FixCut Head
- How to Wrap String on an AutoCut Head
- Comparison Table: FixCut vs AutoCut
- Tips for Optimal String Performance
- Common Mistakes and How to Avoid Them
- Maintenance and Storage Advice
- Frequently Asked Questions
- Conclusion
Understanding Stihl Trimmer Heads
Stihl offers several cutting head designs, but the FixCut and AutoCut models dominate the residential and light‑commercial markets. Both heads use a replaceable nylon line, yet they differ in how the line is fed, tensioned, and replaced. Knowing which head you have is the first step in mastering how to wrap Stihl weed eater string for your specific machine.
FixCut vs AutoCut
The FixCut head is a fixed‑spool design. The line is wound onto a spool that sits inside a housing; the spool does not rotate during operation. When the line wears down, you must remove the spool, unwind the old line, and manually wind new line onto the spool before reinstalling it. The AutoCut head, by contrast, features a semi‑automatic feed system. A spring‑loaded bump knob advances line when you tap the head on the ground. The spool in an AutoCut head can be removed for reloading, but the winding process is slightly different because the line must be threaded through the feed eyelets before winding.
When to Replace String
Replace the line when it becomes shorter than about 2 inches, when it frays excessively, or when cutting performance noticeably declines. Running a trimmer with too‑short line forces the motor to work harder, increasing fuel consumption and wear. Regular inspection—ideally before each use—keeps the trimmer running efficiently and prevents unexpected line breakage during a job.
Tools and Materials Needed
Before you begin, gather the following items. Having everything at hand reduces downtime and ensures a smooth reload process.
- Replacement trimmer line (correct diameter for your model—typically .080 in., .095 in., or .105 in.)
- Protective gloves to protect hands from sharp line ends
- Safety glasses or goggles
- Clean rag or shop towel
- Small flat‑head screwdriver (only needed for some older FixCut models with a retaining screw)
- Owner’s manual for reference to model‑specific line length and winding direction
Preparing the Trimmer
Safety first. Turn off the engine and disconnect the spark plug wire (or remove the battery on cordless models) to prevent accidental starts. Allow the cutting head to cool if the trimmer has been running. Place the trimmer on a stable workbench or the ground with the cutting head facing upward. Clean any grass clippings, dirt, or debris from the head housing; a clean workspace prevents contaminants from entering the spool mechanism.
How to Wrap String on a FixCut Head
The FixCut head requires manual winding of the line onto a stationary spool. Follow these steps carefully to avoid uneven winding, which can cause line feed problems later.
Removing the FixCut Spool
- Locate the retaining knob or screw on the side of the FixCut housing. Turn it counter‑clockwise to release the spool.
- Pull the spool straight out of the housing. Note the orientation of the spool’s arrows—most spools have an arrow indicating the correct winding direction.
- Remove any remaining old line from the spool. Discard the old line responsibly.
Winding the FixCut Line
- Cut a length of new line according to the manual—typically 10–12 feet for a standard residential spool.
- Insert one end of the line into the anchor hole on the spool. Pull it through until about 2 inches remain protruding.
- Wind the line neatly and tightly in the direction indicated by the arrow (usually clockwise when viewing the spool from the top). Keep each turn snug against the previous one; overlapping or loose turns cause feeding issues.
- Leave approximately 6 inches of line free at the end. This tail will be threaded through the eyelet on the housing during reassembly.
- If your spool has two separate winding chambers (dual‑line models), repeat the process for the second chamber, ensuring both lines are wound in the same direction.
Reassembling the FixCut Head
- Thread the free line ends through the corresponding eyelets on the housing. Pull each line until the spool seats fully.
- Replace the spool into the housing, aligning any notches or tabs.
- Secure the retaining knob or screw by turning it clockwise until snug. Do not overtighten; the spool should rotate freely when the trimmer runs.
- Reconnect the spark plug wire or battery, start the engine, and tap the head lightly on grass to verify proper line feed.
How to Wrap String on an AutoCut Head
The AutoCut head’s bump‑feed mechanism requires the line to be threaded through feed eyelets before winding. The steps below walk you through the process.
Removing the AutoCut Spool
- Press the release tabs on the sides of the AutoCut housing (or turn the retaining collar counter‑clockwise, depending on model) to free the spool.
- Lift the spool out, taking note of the line guide channels molded into the spool body.
- Discard any worn line and clean the spool channels with a rag.
Winding the AutoCut Line
- Cut the new line to the length specified in the manual—usually 12–15 feet for a single‑line AutoCut, or two equal lengths for dual‑line versions.
- Insert one end of the line into the anchor hole on the spool. Pull through until a short tail (about 2 inches) remains.
- Wind the line in the direction shown by the arrow on the spool (typically clockwise). Keep the winding tight and even; avoid crossing the line over itself.
- When you reach the end of the line, leave a 6‑inch tail. This tail will be fed through the external eyelet on the housing.
- For dual‑line models, repeat the winding on the second chamber, ensuring both lines are wound in the same direction.
Reassembling the AutoCut Head
- Thread each line tail through the corresponding feed eyelet on the housing. Pull the lines until the spool clicks into place.
- Snap the retaining collar or press the release tabs back into the locked position.
- Reconnect the spark plug wire or battery, start the trimmer, and bump the head on the ground a few times. The bump‑feed should advance line smoothly.
Comparison Table: FixCut vs AutoCut
| Feature | FixCut | AutoCut |
|---|---|---|
| Line Feed Method | Manual – spool does not rotate | Semi‑automatic bump feed |
| Reloading Complexity | Simple manual winding | Requires threading through eyelets before winding |
| Typical Line Diameter | .080 in. – .105 in. | .080 in. – .105 in. |
| Best For | Light residential use, infrequent line changes | Frequent use, faster line advancement |
| Maintenance | Occasional spool cleaning | Periodic bump‑knob lubrication |
| Cost of Replacement Parts | Generally lower | Slightly higher due to feed mechanism |
Tips for Optimal String Performance
- Always use Stihl‑approved line or a high‑quality equivalent that matches the recommended diameter. Cheap line can melt, fray, or break prematurely.
- Store replacement line in a cool, dry place away from direct sunlight. UV exposure degrades nylon over time.
- When winding, keep the line under slight tension. A loose wind creates gaps that cause the line to snag during feed.
- Trim the line ends at a 45° angle after reloading. Sharp, angled ends feed more smoothly through the eyelets.
- If you notice excessive vibration after reloading, double‑check that the spool is seated evenly and that the retaining knob is not overtightened.
- For heavy brush, consider a thicker gauge line (e.g., .105 in.) even if your head accepts thinner line; the added mass improves cutting power.
Common Mistakes and How to Avoid Them
- Winding in the wrong direction. Most spools have an arrow; winding opposite to that arrow causes the line to unwind during operation. Always verify the arrow before you start.
- Overfilling the spool. Packing too much line prevents the spool from rotating freely (FixCut) or jams the bump‑feed mechanism (AutoCut). Leave the recommended free tail length.
- Using mismatched line diameters. A line that is too thick will not fit through the eyelets; a line that is too thin may break under load. Consult the manual for the exact specification.
- Neglecting to clean the housing. Grass buildup can interfere with line feed and cause premature wear. Wipe the housing each time you reload.
- Forgetting to disconnect the spark plug. Accidental starts while your hands are near the cutting head can cause serious injury. Always disable the ignition source first.
Maintenance and Storage Advice
Regular maintenance extends the life of both the cutting head and the trimmer. After each use, remove the spool and blow out any debris with compressed air or a soft brush. Inspect the spool for cracks or warping; replace it if damaged. Lubricate the bump‑knob threads on AutoCut heads with a light machine oil once per season to keep the feed action smooth. When storing the trimmer for an extended period, remove the line entirely to prevent the nylon from developing a permanent set. Store the trimmer in a dry, temperature‑controlled environment, and keep the spark plug wire disconnected.
Frequently Asked Questions
What gauge string should I use for my Stihl trimmer?
Check the owner’s manual for the exact gauge. Most residential Stihl trimmers accept .080 in., .095 in., or .105 in. line. Using the manufacturer‑specified gauge ensures proper feed and cutting performance.
How often should I replace the trimmer line?
Replace the line whenever it wears down to less than 2 inches, shows significant fraying, or when cutting efficiency drops. For heavy daily use, this may be every few hours; for occasional home use, it could be once per season.
Can I use non‑Stihl brand line in my FixCut or AutoCut head?
Yes, provided the line matches the required diameter and is a high‑quality nylon trimmer line. Low‑quality line may melt or break, causing feed problems and potential damage to the head.
Why does my line keep breaking shortly after reloading?
Common causes include winding the line too loosely, using the wrong diameter, hitting hard objects (rocks, metal edging), or a damaged eyelet that cuts the line. Inspect the spool and housing for rough edges and ensure proper winding tension.
How do I adjust the line length on an AutoCut head?
The AutoCut head automatically feeds line when you bump the head on the ground. If the line is too long, let the trimmer run at low speed and gently tap the head until the desired length is achieved. If it is too short, bump the head a few more times to advance additional line.
Conclusion
Mastering how to wrap Stihl weed eater string for both FixCut and AutoCut heads empowers you to keep your trimmer running at peak performance with minimal downtime. By understanding the differences between the two head types, gathering the right tools, and following the detailed winding procedures outlined above, you can reload line quickly and avoid the common pitfalls that lead to poor feed or premature line breakage. Regular inspection, proper storage, and adherence to the manufacturer’s line specifications will further extend the life of your equipment. With these practices in place, your Stihl trimmer will deliver clean, efficient cuts season after season.