The exceptional durability of CBN (cubic boron nitride) grinding wheels is one of the key reasons woodturners have been fast to adopt them; you can quickly restore a keen edge or adjust tip geometry without ever having to spend time truing a wheel or adjusting a sharpening jig to compensate for wear. Nearly as hard as diamond, CBN can grind even hard steels quickly and lasts a remarkably long time. Over the long term, it provides more sharpening per dollar than any other abrasive we know of.