An annular grinding stone is provided which includes a cutting edge with a plurality of V-shaped slits defined in an outer circumferential portion thereof is provided. Each of the V-shaped slits is defined by a first surface and a second surface of the annular cutting edge. The first surface is positioned rearwardly of the second surface with respect to a direction along which the annular grinding stone rotates, and the second surface is positioned forwardly of the first surface with respect to the direction along which the annular grinding stone rotates. The first surface lies perpendicularly to the direction along which the annular grinding stone rotates at a radially outer end thereof and parallel to thicknesswise directions of the annular cutting edge. The second surface is inclined with respect to the first surface at an angle ranging from 30 to 60.

A hubbed blade to be mounted on a spindle includes a circular hub and a circular blade fixed on a side of a first side of the hub. The blade has an opening formed through its center. The hub includes a protrusion portion protruding from the first side and having an outer peripheral edge of a shape corresponding to a shape of the opening. The hub and the blade are connected together via an adhesive with the hub and the blade being aligned each other with the protrusion portion inserted in the opening.

A hubbed blade to be mounted on a spindle includes a circular hub and a circular blade fixed on a side of a first side of the hub. The blade has an opening formed through its center. The hub includes a protrusion portion protruding from the first side and having an outer peripheral edge of a shape corresponding to a shape of the opening. The hub and the blade are connected together via an adhesive with the hub and the blade being aligned each other with the protrusion portion inserted in the opening.

A hubbed blade to be mounted on a spindle includes a circular hub having an opening formed through a center thereof, and a circular blade fixed on a side of a first side of the hub. The hub has a first raised portion and a second raised portion. The first raised portion is circular, is disposed along an outer peripheral edge of the hub, and protrudes from the first side of the hub. The second raised portion is disposed so as to surround the opening on an inner side than the first raised portion in a radial direction of the hub, and protrudes from the first side of the hub. The hub and the blade are connected together via an adhesive applied to a plurality of regions on an end face of the second raised portion.

A hubbed blade to be mounted on a spindle includes a circular hub having an opening formed through a center thereof, and a circular blade fixed on a side of a first side of the hub. The hub has a first raised portion and a second raised portion. The first raised portion is circular, is disposed along an outer peripheral edge of the hub, and protrudes from the first side of the hub. The second raised portion is disposed so as to surround the opening on an inner side than the first raised portion in a radial direction of the hub, and protrudes from the first side of the hub. The hub and the blade are connected together via an adhesive applied to a plurality of regions on an end face of the second raised portion.

A processing apparatus includes a cutting blade mounted on a spindle, the cutting blade having a cutting edge for cutting a workpiece held on a holding table, a measuring portion for measuring an edge projection amount of the cutting edge at a predetermined frequency, and a data processing portion. The data processing portion includes a lower limit recording portion for recording a lower limit of the edge projection amount of the cutting edge as an allowable limit for use of the cutting blade, a storing portion for storing blade information including the edge projection amount measured by the measuring portion and a cutting distance traveled by the cutting blade at the time of measurement of the edge projection amount.

A bonded abrasive article comprises a bonded abrasive matrix. The bonded abrasive matrix comprises, based on the total weight of the bonded abrasive matrix: 10 to 30 weight percent of phenolic binder; abrasive particles retained in the phenolic binder; and from 0.001 to 9 weight percent of ethyl maltol. Methods of making and using are also disclosed.

A bonded abrasive article comprises a bonded abrasive matrix. The bonded abrasive matrix comprises, based on the total weight of the bonded abrasive matrix: 10 to 30 weight percent of phenolic binder; abrasive particles retained in the phenolic binder; and from 0.001 to 9 weight percent of ethyl maltol. Methods of making and using are also disclosed.

A cutting or grinding tool includes a blade. The blade includes a disc-shaped base metal, cutting or grinding tips (edges) provided on a peak (outer circumferential edge) of the base metal, and a protruding coating on a side face of the base metal along the entire outer circumference of the base metal.

A cutting or grinding tool includes a blade. The blade includes a disc-shaped base metal, cutting or grinding tips (edges) provided on a peak (outer circumferential edge) of the base metal, and a protruding coating on a side face of the base metal along the entire outer circumference of the base metal.