Twist drill grinding defect indicator - displays tip angle and tip deviation from drill centre using test head and setting wheel

摘要

The device checks and demonstrates grinding defects in twist drill cutting. A drill is laid with its cutting edge vertical in grooves (16, 17) and positioned by lifting mechanisms (21, 22) with the cutting edge middle at the level of the measuring rulers. The setting wheel (18) moves the test head (6) across the drill until the tip lies in the centre of the measuring rulers. The deviation is indicated on the scale (7). The measuring rulers are swung by setting wheels (11, 12) to lie against the drill tip sides and the tip angle is read.