Types of Drill Bits
Types of Drill Bit
There are many different types of drill bits available which we’ll look at in this section. In the drill bit guide below, we’ve split them into three categories: type of drilling application or material being drilled, the best types of drill bits, and then shank types.
Drill bit material guide: Drilling applications
The most important factor to consider when buying a drill bit is the type of material you’re drilling into. This will determine the type of metal and coating the drill bit is made from and the shape of the cutting lip.
Here’s a list of the best types of drill bit to use for the most popular drilling applications or material types:
What drill bit for masonry?
A specialist masonry drill bit is the best type of drill bit to use if you’re drilling into brick, block, concrete, natural or artificial stone. They prevent the likelihood of chips and cracking and can help to reduce noise levels. They’re typically made from high-speed steel with a tungsten carbide cutting lip. They can have two, three or four cutting lips – the more cutting lips there are, the harder the material it will cut into. Most masonry drill bits can be used with a hammer action drill, but check before buying.
What drill bits for metal?
Specialist metal drill bits are the best drill bits for metal. However, not all metals are the same as some are harder or denser than others. So, it's important to consider what type of metal you are drilling as the drill bit must be harder than the metal it's drilling. For example, drill bits made from high-speed steel (HSS) are fine for soft metals, while cobalt is the best drill bit for stainless steel. But solid carbide or tungsten carbide drill bits are needed to cut through hard, dense metals. Also, check the drill bit's coating. A TiN coating will slow down wear and tear and increase resistance to abrasion and heat, and SG is best for penetrating dense metals.
What multi-material drill bit?
If you want a drill bit that can tackle a range of materials, then a multi-material drill bit or a metal drill bit is ideal. Multi-purpose drill bits are usually made from high-speed steel (HSS) or cobalt and have a tungsten carbide tip.
What drill bit for tiles?
To drill ceramic tiles, use a specialist tile drill bit designed to cut through class 4 tiles (tiles used in high traffic areas). These drill bits have a diamond-shaped point made from tungsten carbide that's designed to cut through the ceramic without causing the tile to chip or crack. They also have a centring tip that stops the drill bit from slipping or wandering. A masonry drill bit can also be used on tiles if used at a slow speed and without the hammer action.
What drill bit for tile and glass?
To drill tiles and glass with a class 3 rating (used in light to moderate traffic areas), use a specialist tile and glass drill bit. These drill bits have a tungsten carbide tipped diamond-shaped point. They can withstand the high temperatures created when drilling into tile and glass.
What wood drill bit types?
Most drill bits will drill through wood, but the best drill bits for wood are specialist wood drill bits. Most are made of steel, and different types of wood drill bits are available to drill different size holes. A twist bit is used to drill holes up to around 17-20mm and is better for drilling thick wood, while a flat drill bit can drill large holes from 13mm upwards in shallow wood. Some wood drills are three-point bits used in carpentry to drill small holes.
Drill bit types explained
Drill bits can also be categorised by the type of hole they cut or their usage. Each one is usually suitable for drilling into specific types of materials too. Here are the most common types:
Auger drill bits explained
Auger drill bits are designed for deep, clean drilling into thick, dry wood. They have a more pronounced central point or spur than standard wood drill bits, making it easy to locate the point that's being drilled and keep the hole on course. This type of wood drill bit is ideal for precision drilling and creating neat holes. So, this is the best wood drill bit to use if appearance is important.
Brad point drill bits explained
Brad point drill bits are another type of wood drill bit that offers precision drilling. They have a pronounced point at the end to ensure the bit stays in the right place and extra-wide flutes that help remove the waste material quickly. They also come with rubber stoppers which allow you to set how deep you want to drill into the wood.
Combination drill bits explained
Combination drill bits is the term used for drill bit sets containing multiple drill bit types suitable for various materials and uses. These sets are ideal for tradespeople or DIYers who need drill bits for a range of jobs rather than someone specialising in working with specific material types.
Cone drill bits explained
Cone drill bits are specialist drill bits used for drilling holes in plastic pipes and sheet metal up to 2mm thick. They are made from high-speed steel (HSS) and have a TiN coating to reduce friction. They have a cone-shaped point, making it easy to drill holes of different diameters without changing the drill bit size.
Countersink drill bits explained
Countersink drill bits are used to drill conical holes that enable flat-headed screws to sit flush against the material being worked on. Most countersink drill bits are designed to drill into wood, but some can drill into metal and minimise sharp edges. Also available are combined countersink with clearance drill bits, which allow you to drill the pilot hole and countersink in one operation.
Diamond tile drill bits explained
Diamond tile drill bits are ideal for cutting through tiles and other brittle materials. They have a cylindrical shaped point made of carbide that helps to reduce the risk of the tile chipping or cracking while reducing the amount of dust produced. There are different tile drill bits designed for different types of tiles, so always check to ensure you are buying the right one for the tiles you are drilling.
Flat drill bits explained
Flat drill bits are designed for drilling holes of 13mm or larger into shallow wood. They are also referred to as spade drill bits. They have a pronounced centre point that makes it easy to locate and drill through the centre of the hole, and the hole they produce has a flat bottom. They’re ideal for drilling large holes where the head of a screw or bolt needs to be sunk into the wood. This drill bit should always be used before drilling the pilot hole.
Forstner drill bits explained
Forstner drill bits are specialist drill bits used in woodworking and cabinet making. They create large, flat-bottomed holes which are required for tasks such as fitting hinges. They drill clean and smooth holes into the wood. Some have a pronounced central point for precision drilling, while others don’t.
Hinge drill bits explained
Hinge drill bits are similar to forstner drill bits as they are used to drill the holes needed to fit hinges. With these drill bits, you use the hinge as a template. The head of the drill bit sits in the space for the hole to enable you to cut the hole in the exact location.
HSS drill bits explained
HSS drill bits are an acronym for high-speed steel, which these drill bits are made of. HSS drill bits are used for drilling into wood and plastic materials but are particularly good for soft metals as they are resistant to the heat generated from the fast speed operation.
Mortice drill bits explained
Mortice drill bits are specialist drill bits used in woodworking and cabinet making. They are used to cut square holes, corners or slots into wood to create mortise and tenon joints. They are used in mortising machines or drill presses rather than power drills.
Plug cutter drill bits explained
Plug cutter drill bits are used in professional carpentry work to cut plugs or holes into wood to hide recessed fasteners. They're often used alongside countersink drill bits. They allow the screw head to be inserted below the material's surface rather than flush with it.
Step drill bits explained
Step drill bits have a cone-shaped point with a series of pyramid-shaped steps. They're designed to drill into sheet material and enable you to drill holes of different diameters without changing the drill bit size. In addition, some step drill bits have spiral flutes, which help remove the waste material.
Shank type explained
The shank is the part of the drill bit that’s held in the chuck of a drill. There are several types available, and you should choose the one that matches the chuck of the drill you intend to use:
You can purchase drill bits with these shank types in singles or packs, but drill bit sets with mixed shank types are also available.
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