I use a simple el cheapo "Canadian tire special" angle grinder with a 120 grit sanding disc on it (get a 50 grit to take out dents)...



I balance the blade by hanging it to a piece of string thru the hole...

Thats how they do it at the parcs and recreations dept at work.... if it's good enough for people who do this all day long, it's good enough for me

Red