How to save lawn edger string?

Question:When i edge my lawn, i used up the string so fast, sometimes it take two roll to finish up. it cost about $7 per roll, am i doing something wrong, or the angle is not right, please advise

Answers:
A heavier guage string might help but you also might check how often you tap the bottom to release more string. Also if you are trimming hear concrete or cement or other rough surface you will use up string fast as those surfaces "wear" string pretty badly. Even tree trunks or rough wood is hard on string, especially small diameter string.