Abstract: Edge tool sharpening apparatus for the sharpening of an edge tool having a shank (e.g. a wood drill bit), the apparatus including an axially rotatable abrasive element having a peripheral abrasive surface; and a support device having support surfaces to support the shank of the tool such that its face to be sharpened engages the abrasive surface with the shank axis at an acute angle to the diametral plane of the rotatable abrasive element through the engagement location, the support device providing for automatic compensation for different shank diameters of different drill bits, when supported by the support surfaces, by automatically effecting an increase in the inclination of the diametral plane with increase in the diameter of the shank and such that the acute angle is substantially constant for a range of drill bit shank sizes.