In order to sharpen the drill bit well, it is very important to lay a solid foundation for the next “grinding” only by placing the edge well before grinding. Herewith four formulas to guide the cutting edge grinding process, the effect is better.
1. “the edge flatters the wheel face.”
This is the first step of the relative position of the drill bit and the grinding wheel. Some students often lean on the grinding wheel and start grinding before they have even put the cutting edge on it. It must not wear well. The “cutting edge” here is the main cutting edge, and the “leveling” refers to the horizontal position of the main cutting edge of the part being sharpened.”Wheel face” means the surface of the grinding wheel.”Lean” means to draw close slowly. At this point, the drill should not touch the grinding wheel.
2.”drill shaft Angle release front Angle.”
This refers to the positional relationship between the drill shaft and the surface of the grinding wheel. The “rake angle” is half of 118°±2O, which is about 60°, which is very important. It directly affects the angle of the top of the drill bit, the shape of the main cutting edge, and the level of the transverse edge. Students should be reminded to remember the commonly used angles of 60° in the 30°, 60°, and 90° triangles, which is easy for students to master. Formulas 1 and 2 are the relative positions of the drill bit before grinding. The two should be regarded as a whole. Do not ignore the bevel angle for the balance of the blade, or ignore the blade for the balance of the tilt axis. These errors are common in practice. Now, in the correct position, the drill bit is ready to touch the grinding wheel.
3.”From the blade to the back of grinding back.”
This refers to the slow grinding from the edge of the drill bit along the whole back face. This facilitates heat dissipation and blade grinding. On the basis of the stabilization and consolidation formula one and two, the drill bit can gently touch the grinding wheel for a small amount of cutting edge grinding. The uniformity of the spark should be observed during the cutting edge grinding, the pressure should be adjusted timely, and the cooling of the drill bit should be noted. When the blade starts grinding again after cooling, it is necessary to continue to set the position of the formula one and two, which is often not easy to grasp at the beginning of learning and will often involuntarily change the correctness of their positions.
4.” up and downswing tail don’t become warped.”
This action is also very important in the process of the bit cutting edge grinding. Students often turn the “up and downswing” into “up and down rotation” during the cutting edge grinding, so that the other main blade of the drill bit is destroyed. At the same time, the tail of the drill bit should not be tilted high above the horizontal centerline of the grinding wheel, otherwise, it will blunt the edge and make cutting impossible.