Types of Drill Bits (2023)

FAQs

Types of Drill Bits? ›

Drill bits are generally classified as Twist Drill, Counterbore, Countersink, Flat Bottom Boring, and Specialty.

Drill bits are generally classified as Twist Drill, Counterbore, Countersink, Flat Bottom Boring, and Specialty.

Carbide: The hardest and most brittle of the drill bit materials, it's used mostly for production drilling where a high-quality tool holder and equipment is used. It should not be used in hand drills or even drill presses. These bits are designed to drill into the hardest materials.

A unibit (often called a step drill bit) is a roughly conical bit with a stairstep profile. Due to its design, a single bit can be used for drilling a wide range of hole sizes. Some bits come to a point and are thus self-starting. The larger-size bits have blunt tips and are used for hole enlarging.

How many types of drilling bits ? Currently in the drilling industry, there are two main categories of drilling bits: rolling cutter bits and fixed cutter bits. Plus, bit sizes vary from 3-7/8 inch to 36 inches.

You can find high-speed steel drill bits for wood, fiberglass, PVC, and soft metals, or you can opt for carbide tipped bits for working with tile and masonry. There are also cobalt drill bits to bore through metal, or more general-use products, like black oxide-coated bits or titanium-coated bits.

A twist bit is the most common type of drill bit for home use. It works for general-purpose drilling in wood, plastic and light metal.

Titanium (Coating)

This type of drill bit lasts longer than black oxide. Titanium drill bits tend to drill faster than black oxide and chips move through the flutes better.

Titanium drill bits are high-speed steel drill bits (HSS) that have a titanium oxide coating. They are very hard, and corrosion-resistant. They last much longer than regular HSS drill bits, and they are good for cutting through any metal, including metal sheeting.

Carbide is the strongest drill bit for metal and is typically reserved for professional-grade tools. Black Oxide is a coating added to HSS drill bits that helps reduce friction and speed up drilling through hard metals.

How do I choose a drill bit? ›

“You want a drill bit that's big enough to drill a hole in the wall, and easy to push the anchor in with your thumb,” Donahue explains. “You don't want to have to force it in there. The drill bit should be the same size as the body of the anchor you're using.”

If you know that you'll be drilling through rock like shale, hard limestone, or granite for a serious distance, a tri-cone bit (also called a roller-cone bit) should be your go-to. A PDC bit would also work as long as the rock doesn't get too hard — in that case, it's best to stick with a tri-cone bit.

Go to a hardware or home improvement store for a cobalt bit that is designed specifically for drilling through steel. You want a cobalt bit, as it's a type of high-speed steel (HSS) that has more cobalt in it and is strong enough to cut through hardened steel.

There are three commonly used angles in consumer drill bits: 90-degrees, 118-degrees, and 135-degrees. 90-degree bits are only used for soft materials such as plastic and aluminum, they get dull very fast.

Twist drill bit: this is the most common type of drill bit, it is used to make holes in wood, metal, plastic and many other materials. Most are made of high speed steel (HSS). However, they are not suitable for masonry.

The part that differs between drill bit types is usually the cutting lip. Their different designs make some more suited to cutting through certain materials than others. There are also different designs depending on the power drill they need to fit, and the type of hole being drilled.

Universal drill bits (aka: all-purpose drill bits) are a new trend where ALL drilling tasks are united in a single drill bit, especially for smaller diameters. So rather than separate drill bits for wood, metal and masonry, this is a bit for ALL materials.

Metal drill bits with a partially ground tip are suitable for non-ferrous metals. These include aluminum, copper, brass, zinc, iron and non-alloy steel. Drills made of cobalt-alloy High Speed Steel (HSS-E) or even drill bits with a titanium coating are needed for stainless steel.

Polished steel, black oxide, or titanium nitride (or cheap imitation gold-colored stuff pretending to be TiN) However, by inspection (looking at the business ends of the bits) I can see that the "silver" ones are wood and/or plastic bits, the "black" are masonry bits, and the "gold" are metal/general purpose bits.

Number drill bit gauge sizes range from size 80 (the smallest) to size 1 (the largest) followed by letter gauge size A (the smallest) to size Z (the largest). Although the ASME B94. 11M twist drill standard, for example, lists sizes as small as size 97, sizes smaller than 80 are rarely encountered in practice.

What is the big drill bit called? ›

Augur Bit – Explained

Auger bits are capable of drilling large holes into thick timber with ease. The screw thread at the tip draws the bit into the material while the single spur scribes the circumference of the hole into the timber before the flute gets there to actually make the cut.

The diameter of the hole you drill should be slightly smaller than the diameter of the screw. So, for example, if you're using a 3.5 mm screw, use a drill bit with a diameter of 3 mm. If you're using wall anchors as well as screws, the drill bit and anchors should have the same diameter.

Cobalt bits are more durable than black oxide and titanium nitride bits. Cobalt drill bits are best for drilling metal. DIYers looking for general-purpose drill bits prefer cobalt drill bits over black oxide and titanium nitride bits for improved durability.

The first drill bit was invented long before the first drill. Experts have dated drill bits back to prehistoric times and believe that homo sapiens were using these tools as early as 35,000 BC. These tools were used to bore into multiple types of materials.

Made of Tungsten Carbide this 8.0 mm, special multi-layered coated, 3-fluted drill bit is the only bit that is tough enough to drill through and survive Ultra High Strength Steel, aka Boron Steel. The three cutting edges help spread cutting forces over a greater area, thus helping prevent premature breakage.

Drilling holes in plastic is best done with spur-point drill bits. Also known as dowel bits, they have a center point and two elevated spurs that help keep the bit straight. The point and angle in front of these bits guarantee smooth cutting and reduce the stress in front.

Not only does carbide provide cutting speeds at least four to eight times that of cobalt, but far higher feedrates as well. And because carbide drills also support a feature unavailable with their cobalt cousins—coolant through-the-tool—there's no need to peck.

Pro Tip: Drilling into metal materials can add extra wear and tear on bits, even those designed for metal. Adding a lubricant such as WD-40_® Multi-Use Product can reduce friction and allow for easier drilling and cutting into metallic parts.

Drill at a Slow Speed

In general, it's a good idea to drill through metal using as slow a speed as possible using a drill bit for metal. Hard metals like steel and larger drill bits require even slower speeds. With a small twist bit (1/16 in. to 3/16 in.), you can drill through most metals at 3,000 rpm.

Standard metal drill bits are fine for drilling in soft metals like copper and aluminium. But for hard metals such as stainless steel, it's best to use drill bits made of chrome vanadium, cobalt or titanium carbide. The HSS label indicates that the drill bit is made of a harder grade of metal.

Do you drill stone fast or slow? ›

Keep a slow and steady pace when drilling. High speed generates friction, friction causes heat, and heat damages both your drill bit and the material you're working on. A heat-damaged drill bit will exhibit color changes at the tip.

The best drill for concrete is a masonry bit drill due to its shape and design. The strongest drills for concrete are those with carbide tips. When drilling through concrete, the sharper the drill, the better the performance. Masonry bits drill holes through concrete in two stages.

Drill bits made to drill through concrete are called masonry bits. These are typically thicker and sturdier than carpentry bits in order to bore through thick concrete, brick or stone without warping and snapping.

Cobalt drill bits are incredibly strong. They can be operated at much higher speeds than a standard HSS drill bit. The ability to withstand heat means that cobalt bits perform for long periods without cooling or the need for cutting fluid. They are most often used to cut through hardened and abrasive materials.

Cobalt Drill Bits Pros. As we have seen, both drill bits are made from high-grade materials and perform well. But in terms of strength, solid carbide drill bits are superior, with a hardness of 75 HRC and cobalt's hardness of 65 HRC on a Rockwell scale.

Drill bits make holes in a variety of different common materials. These include different types of wood, metal, plastic, ceramic tile, porcelain and concrete. Different types of drill bits made for steel, aluminum, copper, cast iron, sheet metal, fiberglass, brick, vinyl flooring and more are also available.

Carbide bits are the strongest drill bits material and can cut through hardened steel. But if they are not available, titanium and cobalt drill bits can also be used. However, drilling with either of these bits will take longer than drilling with a carbide drill bit.

High-Speed Steel (HSS) or Titanium-Coated Drill Bits are suitable for most metals. Cobalt Drill Bits are preferable for harder metals like stainless steel or cast iron. Carbide Drill Bits are for tough metals but can be brittle. Always match drilling speed and coolant use to the material to prevent premature wear.

Auger Bits are the most common drill bits to drill wood holes. Auger bits consist of a sharp point on their tip, which assists in drilling efficiency. This tip easily pulls the bit through the wood. An auger bit is a spiral-shaped drill bit intended to drill deep wood holes.

What is a number 3 drill bit? ›

black oxide. Both cobalt and titanium drill bits are used to make holes in hard, tough materials like metal. Cobalt drill bits are the toughest you can get, and have no coating, unlike titanium drill bits. Titanium bits are coated with titanium nitride or carbonitride to reduce the effects of heat.

If you are using a standard drill, bits will fit, whether they are specialised or multi-material bits. If you are using an SDS drill, on the other hand, you will need SDS bit sets.

Ti-N impact driver bits have two main advantages over regular driver bits – a greater torsional strength and a larger breaking angle which gives them greater flexibility and cushioning under impact, increasing their average service life.