STEP 6

For grinding the center of drill and the web of drill, put the chuck set into web thinning. Put the drill gently into shelf grinding until reach the grinding slip. Grind the drill by moving left and right until the noise stops. And then turn to the other side. Grind the drill with the same way.

*If the diameter of drill is over 6mm, please put 2 or 3 stainless sheets on web thinning.