Wood Auger Drill Bit is a commonly used drilling tool, which has a simple structure. Grinding the drill well is very important for workpiece processing, but it is not an easy task to really grind it well. The key lies in mastering the grinding methods and skills, and mastering the methods, coupled with many grinding experiences, can well grasp the grinding scale of the drill bit.
1. Before grinding the drill bit, place the main cutting edge of the drill bit on a horizontal plane with the grinding wheel surface, that is to say, when the cutting edge contacts the grinding wheel surface, the whole edge must be ground. This is the first step in the relative position between the drill bit and the grinding wheel, and then slowly lean toward the grinding wheel surface.
2. This angle is the front angle of the drill bit. If the angle is wrong at this time, it will directly affect the size of the top angle of the drill bit, the shape of the main cutting edge and the bevel angle of the transverse edge. Here refers to the positional relationship between the axis of the drill bit and the surface of the grinding wheel. Here, we should pay attention to the relative horizontal position and angular position of the drill bit before grinding, and give overall consideration to both, and don't neglect the setting angle for balancing the cutting edge, or neglect the balancing of the cutting edge for balancing the angle.
3. After the cutting edge contacts the grinding wheel, it should be grinded from the main cutting edge to the back, that is, the cutting edge of the drill bit first contacts the grinding wheel, and then slowly grinds down along the whole flank. When the drill bit cuts in, it can touch the grinding wheel gently. First, a small amount of grinding should be carried out, and the uniformity of sparks should be observed, the pressure on the hand should be adjusted in time, and the cooling of the drill bit should be paid attention to. It should not be over-ground, causing discoloration of the cutting edge and annealing of the cutting edge. When it is found that the cutting edge temperature is high, the drill bit should be cooled in time.
4. This is a standard drill grinding action. The main cutting edge should swing up and down on the grinding wheel, that is, the hand holding the front part of the drill should swing the drill up and down evenly on the grinding wheel surface. However, the hand holding the handle cannot swing, and the back handle should be prevented from tilting upwards. This is the most critical step, because the bit is worn well or badly, which has a great relationship with it. When the grinding is almost the same, start from the cutting edge and rub it gently at the back corner to make the back of the blade smoother.
5. After grinding one edge, grind the other edge. It must be ensured that the edge is in the middle of the bit axis, and the edges on both sides should be symmetrical.
6. After grinding the two edges, pay attention to grinding the tip of the bit with larger diameter.
After grinding the two edges of the drill bit, there will be a plane at the tip of the two edges, which will affect the center positioning of the drill bit. It is necessary to reverse the angle behind the edges to make the plane at the tip as small as possible. The method is to erect the drill bit, align it with the angle of the grinding wheel, and pour a small groove at the root behind the blade against the tip of the blade. This is also an important point for bit centering and light cutting. Pay attention to the fact that when grinding the chamfer of the tip, it must not be ground on the main cutting edge, which will make the rake angle of the main cutting edge too large and directly affect the drilling.
There is no certain formula for grinding the drill bit, so it is necessary to accumulate experience in practical operation, explore through comparison, observation and repeated experiments, and add certain human intuition to grind the drill bit better