Scileanna meilt agus próiseas druileanna próiseála poll domhain

①Basic points:

(1) Ba chóir go rothlú an roth meilt go réidh

(2) Ba chóir go mbeadh an imlíne cothrom

(3) Ní mór méid mór runout a bhearradh

②Specific method: When the outer edge of the drill bit is worn out, the edge that has become dull should be worn away, otherwise the sticking and noise will occur. The pressure during sharpening should not be too high, and often dipped in water to cool it to prevent overheating annealing and reducing the hardness. After sharpening, the test can be tested with a sample, but the method of visual inspection is often used. Erect the cutting part of the drill bit upright and look at it with both eyes. Since the two main cutting edges are one behind the other, there will be parallax. It is often felt that the two cutting edges are one high and one low. Rotate 180 degrees and look at it several times. The result is the same. The same is true for the rear angle, just look at the same angle of inclination.