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How to Change the String on a Lawn Trimmer

How to Change the String on a Lawn Trimmer. If you happen to be meticulous when it comes to taking care of your lawn, chances are you do more than simply cut the grass. You likely trim the edges with a lawn trimmer. A lawn trimmer uses a cutting string to cut grass and weeds that grow along the edges of sidewalks or driveways. Often, you'll need to change the string on your lawn trimmer.

Clean off any debris from the underside of the lawn trimmer head. Remove the retaining cap (on some models, this cap pulls off and on others it has to be unscrewed) and the spool from the trimmer head.

Cut a new piece of string approximately six feet long. Slip one end through the starter hole on the spool. Wind around the spool in a counterclockwise direction. There are usually arrows on the spool that indicate in which direction to wind the string.

Leave about six inches of string when finished winding string around the spool. Hook this end onto one of the slots on the spool to hold it in place. Push spool back onto trimmer head.

Feed the loose end of the string through the hole on the trimmer head. Pull firmly to release the string from the slot on the spool. Reattach the retaining cap.


Some lawn trimmers are a dual-feed rather than a single-feed. You will find two holes situated directly opposite each other on the trimmer head. Wind the string around the lower part of the spool as well as the upper part and feed two ends through each hole in the trimmer head. For lawn trimmers with screw-on caps, you usually have to turn the cap in a clockwise direction rather than a counter-clockwise direction to remove it.


Do not replace the cutting string on an electric lawn trimmer without first unplugging the trimmer. Check that both the spool and retaining cap are properly secured onto the lawn trimmer head before using the trimmer. If not properly reattached, the cap or spool could fly off the trimmer when in use and cause injury.

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