New drills usually need sharpening before they can be used. Why?
Grinding the drill bit again, grinding the back angle of the arc transition and the proper vertex angle so that the drill can bore smoothly. No sanding is available, but there is no radian in the rear corner, which can cause vibration instability.
We monitor only a bit grinding blade; another edge to teach short, and a big pot. The hole is 60 millimeters deep; this is called a folk prescription, and the drill hole is asymmetric. The hole will appear in the big hole. If there is any deviation between the two sides of the deep hole, the drill will be drilled
What you say does not exist, the new drill is not heavy grinding can be used; cutting edge is yes, the front angle is the drill bit of the spiral groove angle, it is impossible without the front angle, and the back angle is not 0 degrees, the peak angle is not big. It's only in the drilling that produces what I said before, so it's time to rub it again and use it again.
The back angle of the new drill is grinded by the drill mill, which is made of special grinding bit equipment, and the angle is very straight. There is no circular arc R transition. If directly used to drill, drill will produce vibration and beating, the hole will be multi prismatic. Therefore, the new drill is usually used to drill the drill bit again according to the drilling condition, to grind out the back angle of the arc transition and the proper vertex angle, so that the drill bit can be drilled steadily.
The main purpose is to grind the corresponding radian according to the requirements of the workpiece. The back angle of the new drill is grinded by the drill mill, which is made of special grinding bit equipment, and the angle is very straight. There is no circular arc R transition.
