Tradesperson's guide to Drill Bits

In this guide, we’ll break down the different parts of a drill bit in more detail, run through the key categories available, and explain which type of materials they’re suitable for.

What is a drill bit?

A drill bit is the small, detachable tool which can be fitted to the end of a drill, usually used for making cylindrical holes in a selection of materials. Drill bits are available in a wide range of shapes and sizes, each suited to a different task. With the right drill bit, you can make a hole in wood, plastic, various kinds of metal, and even concrete.

Drill Bit Terminology

 Let’s take a closer look at the different parts of a drill bit, and how they’re widely referred to in the industry:

·         Shank: this is the smooth part of the drill bit which sits securely in the rotating spindle of the drill itself.

·         Flutes: also known as channels, flutes begin at the end of the shank, and spiral their way up to the cutting edge.

·         Point: this is the final section of the drill bit; the pointed end which rotates, comprised of the cutting lip and spur.

·         Cutting lip: this sharp edge is what actually carves a hole into the material, and can vary hugely between drill bits.

·         Spur: the very central tip of the point is called the spur. This helps to position and stabilise the drill bit.

Which drill bit do I need? 

When you’re choosing a drill bit, you’ll first need to think about the material you’re planning to drill into and how precise you need the hole to be. That’s because some drill bits make roughly cut holes, while others are capable of creating super crisp clean ones.

Multipurpose Drill Bits  

As you’d expect, multipurpose drill bits are a versatile choice, which can be used for a range of different jobs and materials. It’s never a bad idea to keep a handful of differently-sized, multipurpose bits in your toolbox for upcoming projects. 

Masonry Drill Bits  

If you’re struggling to work out which drill bit works for brick, concrete and other stonework, masonry drill bits are the key. These powerful bits are often made using a combination of tough metals – like steel and tungsten carbide – so they can cut through stone with ease and precision.  

HSS Drill Bits  

HSS (or high speed steel) drill bits are perfect for jobs which require working on metal or a hard wood, like walnut. Durable and heat-resistant, HSS drill bits can be used at higher speeds, so they’re perfect for powering through tough materials.

Self-feed Bits

Used most often by tradesmen like plumbers or electricians, self-feed bits can make big holes in wood, without the application of any pressure. This makes them especially suited to long, repetitive jobs where a lot of holes are required.

Auger Drill Bits

Designed specifically for drilling holes in wood, these often resemble multipurpose drill bits, except for the more pronounced, narrow spur at the tip. It’s this feature that makes auger drill bits capable of precision drilling neat, cleanly cut holes into wood.  

Spade Drill Bits

With their flat, broad shape and pointy tip, spade drill bits are ideal for making larger holes in wood. Thanks to their width, these holes are much bigger in diameter than the average drill hole, but it’s worth noting that they can be pretty rough around the edges.

Once you’ve worked out which drill bit you need, don’t forget you can find a broad range of drill and driver bits here at IronmongeryDirect. We offer bits in many different sizes and materials, from reputable brands like TIMco, so you’re sure to find the right part for your project.