When choosing a drill bit, it is important to ensure that the drill bit that is selected is the right one for the material that is being cut. Drill bits is made from a variety of different materials, and the material from which a drill bit is made impacts the ability of the drill bit to handle heat and to maintain it’s sharpness. Many individuals are unaware of importance of the drill bit material, but it is the most important factor in the functioning of the drill bit.
High speed steel is one of the most common materials from which people make drill bits. High speed steel is used to drill into wood, plastic, and soft metal. High speed steel, however, loses it’s hardness when drill bits becomes hot from the cutting process.
How to Choose the Right Drill Bit
Cobalt drill bits contain five to eight percent cobalt, which allows those drill bits to better withstand high temperature. Cobalt drill bits are, therefore, an better choice for drilling into stainless steel and hardened steel materials. Drill bits can also be coated with various material to improve their performance.
For instance, titanium nitride can coat drill bits, which decreases the friction between the drill bit and the drilled material, increasing the lifespan of the drill bit when drilling into steel or cast iron. Another alternative is to use drill bits that is coated with titanium aluminum nitride, which can stand higher temperatures then other coatings. These additional coatings can act as a buffer between the cutting drill bit and the heat created by friction.
Another category of drill bits includes solid carbide drill bits. Solid carbide is a material that is significantly harder then steel. People use solid carbide drill bits in situations in which an abrasive composite material is being drilled into or in high-production environments.
The downside to solid carbide is that it is also brittle. Due to this brittleness, sideways loads or impacts can easily break solid carbide drill bits if they are placed upon the drill bit. Thus, solid carbide bits are used in drill presses or CNC machine.
Drill bits that contain diamond powder are used for drilling into materials like glass, tile, and stone. Diamond bits are necessary because glass, tile, and stone is harder than other materials for drill bits. The speed at which a drill bit is used and the feed rate at which the drill bit is run are two other factors in the selection of the proper drill bit for a specific task.
If a drill bit is run too fast, the drill bit will overheat and the cutting coatings will be destroyed. If drill bits are run too slowly, the material that is being drilled into has the potential to work-harden. Work-hardened materials is more difficult to cut.
For instance, when drilling into stainless steel, a material that tends to work harden, the speed of the drill bit must be maintained at the proper rate. Additionally, the larger the drill bit, the more slower the rate of the drill bit should be set. Harder materials will require more downward pressure on the drill bit than drill bits that drill into softer materials.
The cost of drill bits relates to the performance of the drill bit. Budget drill bits can be purchased for situations in which you only use drill bits occasionally. However, if an individual is drilling into stainless steel or performing high-production tasks, cobalt or coated drill bits are a better purchase.
Although drill bits that cost more money up front may have a higher initial cost, they will be cheaper in the long run due to the fact that they will drill more finished hole for the same amount of money spent. Finally, drill bits must always be matched to the material that is to be drilled and the volume of work that is to be perform with that drill bit. The match between drill bit and material will ensure that the drill bit remains functional and that the drilling process does not damage the workpiece.
