It took me a long time on the coarse stone w kme roller sharpener to get a batch of grizzlies sharp. Staying with the coarse stone until you get a burr along the entire edge is absolute key! The other thing I found helped was to work the non beveled side along the side of the stone prior to going to work on the beveled side. Once they've sharpened on this you'll find touching them up very easy. 95 percent of your effort will be getting that burr. Ron at kme stayed on the phone w me until I had hair flying off my arm. Remember not to put much pressure and let the stone do the work.