Tried searching the posts but can't find tips on using a walk-behind gas edger (Troy Bilt). My husband doesn't think we need to edge our lawn, but I do, so I spent like $300 on this thing and am having a hard time managing it. I think the wheels are self-propelled so it goes ahead too fast and I can't keep it straight. Sometimes the blade is grinding into the concrete and sounds horrible (don't even want to think about what I'm doing to the blade). Do any of you pros have some tips for me? The edging looks like a complete amateur did it (which of course I am). How do I keep it straight, know where the sidewalk ends and not run into the concrete? Thanks a bunch!