April 9, 2021 in Travels
The drill bit should be a very common tool, among which the drill bit we have heard the most is the wood auger drill bit . However, it is easy to buy a drill bit, and subsequent maintenance and maintenance are not easy. Among them, grinding the drill bit is also a technical task.
The sharpening quality of the drill bit affects the drilling accuracy and the working ability of the drill bit. If the symmetrical configuration of the drill bit edge (or guide center) relative to its axis slightly deviates, it will cause the deflection of the drill bit during the working process. Decrease drilling accuracy. The sharp angle of the cutting edge of the drill depends on the quality of sharpening, material properties, and the geometry of the cutting part of the drill.
The two cutting edges should have the same length; the inclination angles of the two cutting edges relative to the axis of rotation of the drill bit should be the same; the chisel edge of the drill bit should be in a straight line after sharpening, and its center should be consistent with the axis of rotation of the drill bit. The transverse drill bit needs to sharpen the guide center, sinker knife, and cutting edge separately. The main blade is sharpened from the back, the sinking knife is sharpened from the inside (round and toothed sinking knives can be sharpened by hand with a smooth file or a hand file, and then polished with oilstone), and the guide center is to sharpen the tapered surface, The correctly ground guide center should have a symmetrical configuration surface, and the cone center of the cone should be consistent with the drill bit axis.
In addition to the wood auger drill bit, the HSS cobalt drill bit , which is known for its hardness, is also a very popular product.
April 2, 2021 in Travels
Diamond grinding wheels are one of the hardest materials known, and there are two types: natural and man-made. The Diamond cup grinding wheel is made of the diamond as raw material.
Diamond is a mineral composed of pure carbon dioxide. Diamond is the hardest substance in nature. The use of diamonds is very wide, such as handicrafts, a cutting tool in the industry. Carbon can form diamonds at high temperatures and high pressure.
Diamond cup grinding wheel is one of the diamond tools. It is mainly suitable for the surface grinding of various refractory materials. The product adopts a specially designed tapered mounting hole structure, which is easy to install and unload, and has good processing flatness and grinding. The advantages of high cutting efficiency and long life can be applied to all domestic and imported grinding equipment.
When in the form of a single carbon compound, the hardness of tungsten carbide can compete with diamond, and it is the hardest material known. Because tungsten carbide has very good characteristics, it can be widely used. Tungsten carbide hole saws are one of the applications.
March 26, 2021 in Travels
A drill bit is a tool that rotates and has the cutting ability at the tip, so you will see one or two at home, especially wood auger drill bit . Many novices who are grinding drills for the first time, always feel that their drills are not standardized. So today we will talk about the correct posture for grinding the drill.
The cutting edge of the drill must swing up and down, and the tail of the drill must not be warped. This is a standard drill grinding action. The main cutting edge must swing up and down on the grinding wheel, that is, the hand holding the front of the drill must evenly swing the drill up and down on the grinding wheel. However, the hand holding the handle cannot swing, and the rear handle must not be tilted upwards, that is, the tail of the drill bit cannot be tilted higher than the horizontal centerline of the grinding wheel, otherwise the cutting edge will be blunt and unable to cut. This is the most critical step. The quality of the drill bit has a lot to do with it. When the sharpening is almost done, start from the edge of the blade and rub it lightly towards the back corner to make the back of the blade a bit smoother.
Regardless of whether it is an HSS cobalt drill bit or a wood auger drill bit, the posture during grinding is still very important. The quality of the drill bit is determined by this to a large extent, so it is still necessary to learn.
March 19, 2021 in Travels
As a common cutting tool, drill bits must be made of steel to achieve the required hardness. But unlike the stainless steel knives of general kitchen knives, common drill materials are nothing more than HSS cobalt drill bit , tungsten steel drill bits, etc., and there are often so-called “cobalt drill bits” on the market. What does this mean?
Cobalt-containing drill bits are made of cobalt-containing high-speed steel. Cobalt-containing high-speed steel belongs to the “high-hard or super-hard high-speed steel category”. The addition of “cobalt” to ordinary high-speed steel materials can increase the hardness of the tool to HRc 66 degrees, and increase the red hardness (hot hardness) of the tool, thereby increasing the cutting speed and service life of the tool.
Commonly used drills for processing stainless steel are high-cobalt drills (m35 drills, m42 drills), among which m42 drills are the most cost-effective. Cemented carbide drill bits can also be used, but the price is higher.
The above is some understanding of cobalt drill bits, like wood auger drill bit , most of them have high hardness.
March 12, 2021 in Travels
Tungsten carbide hole saws can cut very hard materials, including hardened steel, cast iron, bricks, etc. The shaft made of carbon steel is matched with a centering drill.
The theoretical carbon content of tungsten carbide is 6.128% (atomic 50%). When the carbon content of tungsten carbide is greater than the theoretical carbon content, free carbon (WC+C) appears in the tungsten carbide. The presence of free carbon will carbonize the surrounding area during sintering. The growth of tungsten grains results in uneven grains of cemented carbide; tungsten carbide generally requires high combined carbon (≥6.07%) free carbon (≤0.05%), and total carbon is determined by the production process and scope of use of cemented carbide.
The WC total carbon used in alloys with different application ranges, different cobalt contents, and different grain sizes can be adjusted slightly. Low-cobalt alloys can choose tungsten carbide with higher total carbon, and high-cobalt alloys can choose tungsten carbide with lower total carbon. In short, the specific requirements of cemented carbide have different requirements for the particle size of tungsten carbide.
Cemented carbide materials like tungsten carbide and diamond are usually made into cutting tools, Tungsten carbide hole saws, Diamond cup grinding wheel , etc.
March 5, 2021 in Travels
HSS cobalt drill bit is probably not too unfamiliar to everyone, for some people, it may still be very familiar. Since ancient times, there have been people who have survived by engaging in this industry.
High-speed steel, also known as wind steel or front steel, means that it can be hardened even if it is cooled in the air during quenching, and it is very sharp. It is complex alloy steel, containing carbide-forming elements such as tungsten, molybdenum, chromium, vanadium, and cobalt. The total amount of alloying elements is about 10-25%. It can maintain high hardness even when high heat is generated by high-speed cutting (about 500℃), and the HRC can be above 60. This is the most important characteristic of high-speed steel-red hardness.
After quenching and low-temperature tempering, carbon tool steel has high hardness at room temperature, but when the temperature is higher than 200℃, the hardness drops sharply, and the hardness at 500℃ has dropped to a similar degree to the annealed state. , Completely lost the ability to cut metal, which limits the use of carbon tool steel to make cutting tools. High-speed steel, because of its good red hardness, makes up for the fatal shortcomings of carbon tool steel and can be used to make cutting tools.
Therefore, the hardness of the HSS cobalt drill bit is slightly higher than that of the wood auger drill bit , and the places used are also different.
February 26, 2021 in Travels
For us, the wood auger drill bit is a tool that is too simple to be simpler, but when we observe its shape, we will find that there are complex layers and details under the simple appearance, so we are also polishing the stone. Need to pay attention to the issue of angle.
The correct drill sharpening should accurately maintain the angle values of the cutting elements and their mutual configuration. After sharpening, the end face of the cutting edge swings <0.08mm, and the allowable angle parameter deviation is ±2°. Burns, peeling, etc. are not allowed on the sharpened surface. The sharpening of the drill can be done with a grinding wheel or a hand file. When sharpening the drill bit on the grinder, choose a hard or medium-soft ordinary grinding wheel with a grain size of 46~60 and a grinding wheel speed of 25m/s. When sharpening, the drill bit can be placed in the special guide groove, the entire special fixture can be turned to a certain angle around the axis (rotate in two directions), and the flank surface can be sharpened according to the formed cone.
HSS cobalt drill bit also needs attention when polishing.
February 5, 2021 in Travels
For drill bits, especially those frequently used drill bits, such as wood auger drill bit , the later polishing and maintenance are very important.
The sharpening quality of the drill bit affects the drilling accuracy and the working ability of the drill bit. If the symmetrical configuration of the drill bit edge (or guide center) relative to its axis slightly deviates, it will cause the deflection of the drill bit during the working process. Decrease drilling accuracy. The sharp angle of the cutting edge of a drill depends on the quality of sharpening, material properties, and the geometry of the cutting part of the drill.
The correct drill sharpening should accurately maintain the angle value of the cutting elements and their mutual configuration. After sharpening, the end face of the cutting edge swings <0.08mm, and the allowable angle parameter deviation is ±2°. Burns, peeling, etc. are not allowed on the sharpened surface. The sharpening of the drill can be done with a grinding wheel or a hand file.
For the HSS cobalt drill bit , be more careful when grinding, because HSS has higher requirements for the drill bit.
January 29, 2021 in Travels
Knives or other tools are rusted or shielded, so we need to grind them. But grinding also requires equipment or tools, and the Diamond cup grinding wheel is a piece of good equipment.
Diamond cup grinding wheel has the advantages of good processing flatness, high grinding efficiency, and long life. Also, the Diamond cup grinding wheel is mainly suitable for the surface grinding of various refractory materials. The product adopts a specially designed tapered mounting hole structure, which is easy to install and unload.
Tungsten carbide hole saws are made by welding or cold pressing diamond tips on a metal substrate; diamond tips are made by artificial industrial diamond and other metal powders, cold pressing and hot pressing sintering, and then welded in a bowl On the metal substrate.
Like the Diamond cup grinding wheel, Tungsten carbide hole saws are also a very good tool. Although it is not used for grinding, it is also very good in other aspects.
January 22, 2021 in Travels
Everyone knows that hole saws are very hard materials and can cut a lot of metals, so do you know Tungsten carbide hole saws ? Do you know the composition of tungsten carbide?
Tungsten carbide hole saws can cut wood, plastic, aluminum, steel, chemical fiberglass, drywall, fiberboard, plaster, ceramic tiles, and work surfaces without nails.
Tungsten carbide uses metallic tungsten and carbon as raw materials. Tungsten powder with an average particle size of 3 to 5 μm and carbon black of the same amount are dry mixed with a ball mill. After fully mixing, it is pressed and molded into a graphite plate. Heat to 1400～1700℃ in resistance furnace or induction furnace, preferably 1550～1650℃. In the hydrogen stream, W2C is initially produced and continues to react at high temperatures to produce WC. Or firstly, tungsten hexacarbonyl is thermally decomposed at 650～1000℃ in CO atmosphere to prepare tungsten powder, and then reacted with carbon monoxide at 1150℃ to obtain WC. Temperatures higher than this temperature can generate W2C.
In fact, the raw material diamond of the Diamond cup grinding wheel is also a mineral composed of carbon elements.