"He who marches out of step hears another drum." ~ Ken Kesey
I use a piece of 1 x 1 wood and rub alone the edges if there's not deep nicks, keeps them nice and smooth without grinding away to much metal or a slip up with the grinder...I also do this to my scoop coaters edges.
Or use double sided tape and tape some fine grit sandpaper to a very flat surface and lap the floodbar back and forth on it. For a 16" floodbar you'll want about a 24" wide strip of sandpaper taped down. and be carefull not to rock the floodbar as you hone it, or your finished product wont be straight. then use a sanding sponge to round the edge.