What's the angle of a standard twist drill?
It is divided into 135 degrees and 118 degrees135 degrees vertex angle is mainly used for more hard workpiece, this design is to improve the positioning of the drill bit accurate (because 135 degrees need to open the back angle), broken cutting fastThe drill with a top angle of 118 degrees is mainly used for soft materials. The purpose is to drill holes and feed quickly. That is to say, drilling speed is very fast
If the front angle is too small, the bit strength decreases, the deformation increases, the torque increases, and the drill bit breaks easily. Therefore, a reasonable front angle should be sharpened according to the strength and hardness of the workpiece material. The front angle of the standard twist drill is 2 and phi is 118 degrees
The front angle is 2, and the front angle is the projection angle of the two main cutting edges on the plane parallel to them. The small front angle is easy to cut into the workpiece, the axial resistance is smaller, and the working length of the cutting edge is increased, and the nominal thickness of the cutting layer is reduced, which is beneficial to heat dissipation and to improve the durability of the cutting tool;
How much is the standard twist drill angle - 118 degrees, drawing (the threaded hole is a blind hole at 120 degrees) according to the draw.
