How do you drill a drill?
6, after grinding, the drill rotation, simulation, drilling, cutting the status of inspection, to see if there is no wrong place, if there is further grinding;7, grinding the cross edge, that is, symmetrical sharpening drill bit after the blade;The 8 big bits can be sharpened by grinding on the side of the grinding wheel;9, steel bad twist drill, the vertex angle can be properly worn. .
2, drill clockwise in the same direction, drilling tail down about 10 degrees angle, sharpening;3, drill once rotated 30 degrees angle or slightly larger, pay attention not to sharpen all other cutting edge, grinding two or three times;The 4 supporting point does not change, and the drill rotates 180 degrees, with the same method sharpening all other cutting edges;5, after grinding, the drill will be vertical (to make it natural droop), and hold it in hand, check whether the grinding bit is symmetrical with its center line;In case of asymmetric grinding, the angle between the cross blade and the cutting edge should be 50 degrees --55 degrees;
1 used to hand as a fulcrum, hold the drill, the other hand holding drill tail;2 bit cutting edge level against the wheel at the level of the outer edge of the cutting edge and the edge of the wheel angle is about 60 degrees or smaller (standard 58-59 degrees);
