Popularized by Stuart Batty, the 40/40 grind is widely used across the globe. Ron introduces a set up block for use with the OneWay Wolverine VariGrind 1 for achieving this very popular bowl gouge Popularized by Stuart Batty, the 40/40 grind is widely used across the globe. Ron introduces a set up block for use with the OneWay Wolverine VariGrind 1 for achieving this very popular bowl gouge grind.