Lawn trimmers are popular pieces of landscaping equipment in use by many amateur and professional operators. Most trimmers are designed for easy replacement and refill of the line. Refills take approximately ten minutes on average and are easy for one person to complete. Replacement line is available from any hardware or home improvement store, and comes in various materials and sizes depending on the manufacturer of the trimmer. New line is affordable and even color-coded based on line size.
Remove the spool by turning it to the left and pulling on it slightly. It should come out easily but some require just a bit of force to fully remove.
Clean any debris from the spool ring, the spool housing and any other areas that should be cleaned at this time. For caked on matter use a putty knife to scrape it free. For loose material or dirt, use a damp sponge to clean the spool and make sure the system works well.
Unroll a sufficient amount of replacement line and cut it with clippers or a utility knife. Feed one end of the new line through the retaining hole in the spool ring and crimp the line with pliers at a 1/2-inch length. These holes are usually marked clearly.
Wrap the line around the spool in the direction indicated on the spool itself. This is usually shown by an arrow or other marking. Try to wrap the line smoothly so that it doesn't bind between the wrapped rows. Insert the end of the line through the feed hole in the side of the spool ring.
Run the leading line into the spool housing and out the hole cut into the housing. Press the spool into the spool housing and twist it slightly to the right until it locks into place. Pull gently on the end of the line to get it taught.