![]() They offer much greater diameters than twist or stepped drills, but depth of cut is restricted. Hole saws: Hole saws are most often used for wood or masonry, but tungsten- and titanium-tipped models are available for cutting metal.It’s important to check the depth of each step, as this defines the maximum thickness of the sheet it is capable of drilling. Each drill bit can contain between 6 and 12 different cutting diameters, in ever-increasing steps. Stepped drills: These offer versatility when drilling thin sheet material.Bits for drilling ferrous metals may have a 135° or 140° angle. A 118° angle is probably the most common, and it is considered optimum for non-ferrous metals. Twist-drill bits: Most metalworking drill bits follow a fairly standard twist-drill pattern with two flutes running down the sides to help clear waste.Professional woodworkers will probably want to make that investment, but do-it-yourself users will often find one of the other options perfectly adequate. The latter is harder but is also more brittle, so M35 is more common.Ĭobalt undoubtedly produces the best metalworking drill bits, capable of drilling both non-ferrous and ferrous metals. There are two types of cobalt drill bit: M35, which contains 5% cobalt, and M42, which contains 8% cobalt. As a result, cobalt creates the most durable metalworking drill bits, capable of being resharpened over and over again. So cobalt is added to HSS during production. Often, these drills are considered disposable.Ĭobalt: These drill bits are not coated, but are formed as an alloy. Resharpening is possible, though the coating will eventually wear through, leaving only the HSS core. Buy from recognized brands to avoid disappointment.Ĭoncerns with coatings: The main drawback with tungsten carbide, black oxide, and titanium is that each is a coating. However, cheap sets sold as metalworking drill bits might have gold plating but don’t actually contain any titanium nitride. ![]() Titanium drill bits can drill both non-ferrous and ferrous metals (steel and cast iron).Ī note of caution: Titanium drill bits are often gold in color. Titanium also reduces friction between the drill bit and the material being drilled, so it offers good heat dissipation - and, since overheating is a major cause of wear, greater durability. Like carbide and black oxide, it increases the drill bit’s hardness. It is technically a ceramic, rather than a metal. Titanium (or TiN, titanium nitride): This is another form of coating applied to a HSS drill bit. Black oxide drills are a good general-purpose choice, capable of efficient drilling of a wide variety of materials, including non-ferrous metals. The resulting drill bit can be 50% harder than HSS. Carbide drill bits can produce acceptable performance in non-ferrous metals, but while popular for masonry drills, the material is not often used for metalworking drill bits.īlack oxide: This coating is created by a chemical reaction between high-speed steel and sodium at high temperatures. Tungsten carbide (often just called carbide): This is a tungsten-and-carbon composite fused to a HSS core to increase drill bit hardness. However, HSS is softer than other drill bits for metal and wears quickly. HSS is great for drilling wood and plastic, and it can also drill through non-ferrous metals (those that don’t contain iron) such as aluminum and brass. Several of the other types of metalworking drill bits also have HSS at their core. ![]() As a result, it is used for all kinds of cutting tools. High-speed steel (HSS): The most common drill bit material, it is relatively hard, affordable, and easy to manufacture in different forms. ![]() Key metalworking drill bit set features Metalworking drill bit materials and coatings Allow time for the drill bit to cool before trying to change it. Drilling metal creates a great deal of heat.
0 Comments
Leave a Reply. |
Details
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |