This is the area machined by the radius edge of the grinding wheel where the journal ends and the web starts. This machined fillet area is very important in preventing cracks and broken shafts. When grinding cranks it is extremely important to maintain the recommended manafacturers profile of this fillet radii. When straightening a shaft using punches in this area it is important to restore this radii position and remove any dints or scratches. This area is often rolled or shot penned to stress relieve the shaft.