I use the cardboard wheels daily. They take the wire edge off very clean and razer sharp. I bought mine at Koval. All the knife catalogs sell them in a 2 wheel set. They come complete with 2 wheels, extra grit to redress the grinding wheel and grease for each wheel. They fit any standard bench grinder and come in 6" and 8" diameter, only cost about $19.95 or so. Bruce