i saw a pretty good diy trimmer using a one of those dremils and some weed wacker line. it was pretty neat and the guy said it cost him 20 bucks at harboe freight. i am sure you could use your cordless drill. then you can adjust speeds as you pull the trigger. so take anything that fits in the chuck of you drill and drill and hole in it the size of weddwacker string and you have your own trimmer. sorr i thought it said timer earlier. but very simple diy and you can save the money for the electric bill. or more nutes