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How to Load a Lawn String Trimmer

By Frank Whittemore ; Updated September 21, 2017

String trimmers make keeping your lawn manicured quick and easy. That string won't last forever, though, and will eventually need to be replaced. As the trimmer cuts, the string wears out and breaks off. The plastic string is wound on a spool in the cutting head of the trimmer that feeds new string into the cutting area when you tap the head on the ground. Eventually, all the string on the spool will be used. It is a relatively easy procedure to reload a lawn string trimmer.

Removing the Spool and Preparing the String

Turn off or unplug the string trimmer.

Remove the retainer that holds the spool in place on the underside of the cutting head and set it aside.

Remove the spool from the cutting head. You may notice a spring on the spool. Keep the spring in place. Remove any old string from the spool.

Cut a length of new trimmer string 9 feet long. If the trimmer requires two strings, cut another of equal length.

Loading the Spool

Hold the spool with the spring facing up and insert the end of a string into the little anchor hole in the side of the spool. If the trimmer uses two strings, install the string in the upper area first.

Check the spool for an arrow that indicates the direction to wind the string. Wind the string around the spool until approximately 6 inches remain.

Press the string into one of the string retention slots in the upper spool flange.

If the trimmer takes two strings, Insert the second string into the anchor hole in the lower area of the spool.

Wind this string around the lower area of the spool until approximately 6 inches remain and press the string into the other string retention slot in the upper spool flange.

Replacing the Spool

Insert the end of each string through a guide hole in the cutting head and pull through to around 5 inches.

Position the spring over the string head shaft and press the spool down onto the shaft.

When the spool is properly positioned, pull the strings sharply to release them from the retention slots.

Rotate the spool until it no longer turns.

Replace the spool retainer, turning accordingly to tighten it to the shaft.

Pull the strings once more to align the spool into cutting position.


Things You Will Need

  • Trimmer string
  • Scissors


  • Check your trimmer's manual before purchasing replacement string. It comes in a variety of diameters, sized to fit through the hole in each particular trimmer's cutting head.

About the Author


In Jacksonville, Fla., Frank Whittemore is a content strategist with over a decade of experience as a hospital corpsman in the U.S. Navy and a licensed paramedic. He has over 15 years experience writing for several Fortune 500 companies. Whittemore writes on topics in medicine, nature, science, technology, the arts, cuisine, travel and sports.