Grass trimmers are used for precision cutting of grass that has been missed by mowers.
Instead of steel blades, nylon string is used to cut the grass.
Accidental damage to objects at the edges of the lawn (fences,trees) is also minimized.
Popular brands include Ryobi, Echo, Homelite and Stihl.
Fixed cut-length trimmers are the simplest and most reliable.
A short length of pre-cut string (typically 7 to 17 inches) is fixed to the cutting head.
The ends of the string are gradually worn down cutting grass.
When it is too short to cut effectively, the string is manually replaced.
Advantages
Disadvantages
Bump feed spool systems are more convenient but less reliable.
Many yards of string are wound on to a spool, like on a fishing rod.
Lightly tapping the cutting head on to the ground causes the spool to feed a few inches of line.
On some models, turning the power off and on will feed more string.
Automatic feed spool systems are available on newer models.
Advantages and disadvantages are similar to bump feed systems.
Gas trimmers are the most powerful, available in up to 17 inch wide cutting paths.
Less powerful trimmers are safer, throwing stones and excess cut string with less energy.
Reliability problems continue to plague spool feed mechanisms.
An Internet search should be made for user reviews of specific models.
